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Sample records for shrews mammalia soricidae

  1. Functional skeletal morphology and its implications for locomotory behavior among three genera of myosoricine shrews (Mammalia: Eulipotyphla: Soricidae)

    USGS Publications Warehouse

    Woodman, Neal; Stabile, Frank A.

    2015-01-01

    Myosoricinae is a small clade of shrews (Mammalia, Eulipotyphla, Soricidae) that is currently restricted to the African continent. Individual species have limited distributions that are often associated with higher elevations. Although the majority of species in the subfamily are considered ambulatory in their locomotory behavior, species of the myosoricine genus Surdisorex are known to be semifossorial. To better characterize variation in locomotory behaviors among myosoricines, we calculated 32 morphological indices from skeletal measurements from nine species representing all three genera that comprise the subfamily (i.e., Congosorex, Myosorex, Surdisorex) and compared them to indices calculated for two species with well-documented locomotory behaviors: the ambulatory talpid Uropsilus soricipes and the semifossorial talpid Neurotrichus gibbsii. We summarized the 22 most complete morphological variables by 1) calculating a mean percentile rank for each species and 2) using the first principal component from principal component analysis of the indices. The two methods yielded similar results and indicate grades of adaptations reflecting a range of potential locomotory behaviors from ambulatory to semifossorial that exceeds the range represented by the two talpids. Morphological variation reflecting grades of increased semifossoriality among myosoricine shrews is similar in many respects to that seen for soricines, but some features are unique to the Myosoricinae.

  2. Functional skeletal morphology and its implications for locomotory behavior among three genera of myosoricine shrews (Mammalia: Eulipotyphla: Soricidae).

    PubMed

    Woodman, Neal; Stabile, Frank A

    2015-05-01

    Myosoricinae is a small clade of shrews (Mammalia, Eulipotyphla, Soricidae) that is currently restricted to the African continent. Individual species have limited distributions that are often associated with higher elevations. Although the majority of species in the subfamily are considered ambulatory in their locomotory behavior, species of the myosoricine genus Surdisorex are known to be semifossorial. To better characterize variation in locomotory behaviors among myosoricines, we calculated 32 morphological indices from skeletal measurements from nine species representing all three genera that comprise the subfamily (i.e., Congosorex, Myosorex, Surdisorex) and compared them to indices calculated for two species with well-documented locomotory behaviors: the ambulatory talpid Uropsilus soricipes and the semifossorial talpid Neurotrichus gibbsii. We summarized the 22 most complete morphological variables by 1) calculating a mean percentile rank for each species and 2) using the first principal component from principal component analysis of the indices. The two methods yielded similar results and indicate grades of adaptations reflecting a range of potential locomotory behaviors from ambulatory to semifossorial that exceeds the range represented by the two talpids. Morphological variation reflecting grades of increased semifossoriality among myosoricine shrews is similar in many respects to that seen for soricines, but some features are unique to the Myosoricinae. PMID:25678028

  3. Can they dig it? Functional morphology and semifossoriality among small-eared shrews, genus Cryptotis (Mammalia, Soricidae)

    USGS Publications Warehouse

    Woodman, Neal; Gaffney, Sarah A.

    2014-01-01

    Small-eared shrews (Mammalia: Soricidae: Cryptotis), exhibit modifications of the forelimb skeleton that have been interpreted as adaptations for semifossoriality. Most species inhabit remote regions, however, and their locomotory and foraging behaviors remain mostly speculative. To better understand the morphological modifications in the absence of direct observations, we quantified variation in these species by measuring 151 individuals representing 18 species and populations of Cryptotis and two species of moles (Talpidae) for comparison. From our measurements, we calculated 22 indices, most of which have been used previously to characterize substrate use among rodents and other taxa. We analyzed the indices using 1) average percentile ranks, 2) principal components analysis, and 3) cluster analysis. From these analyses, we determined that three basic modes of substrate adaptation are present within Cryptotis: 1) a primarily terrestrial mode, with species that are capable of burrowing, but lack adaptations to increase digging efficiency, 2) a semifossorial mode, with species whose forelimbs bones show strong muscle attachment areas and increased mechanical advantage, and 3) an intermediate mode. In addition to identifying new morphological characters and contributing to our understanding of the functional morphology of soricids, these analyses provide additional insight into the ecology of the species of interest.

  4. Skeletal morphology of the forefoot in shrews (Mammalia: Soricidae) of the genus Cryptotis, as revealed by digital x-rays

    USGS Publications Warehouse

    Woodman, N.; Morgan, J.J.P.

    2005-01-01

    Variation in the forefoot skeleton of small-eared shrews (family Soricidae, genus Cryptotis) has been previously documented, but the paucity of available skeletons for most taxa makes assessment of the degrees of intraspecific and interspecific variation difficult. We used a digital X-ray system to extract images of the forefoot skeleton from 101 dried skins of eight taxa (seven species, including two subspecies of one species) of these shrews. Lengths and widths of each of the four bones of digit III were measured directly from the digital images, and we used these data to quantify variation within and among taxa. Analysis of the images and measurements showed that interspecific variation exceeds intraspecific variation. In fact, most taxa could be distinguished in multivariate and some bivariate plots. Our quantitative data helped us define a number of specific forefoot characters that we subsequently used to hypothesize evolutionary relationships among the taxa using the exhaustive search option in PAUP, a computer program for phylogenetic analysis. The resulting trees generally concur with previously published evolutionary hypotheses for small-eared shrews. Cryptotis meridensis, a taxon not previously examined in recent phylogenies, is rooted at the base of the branch leading to the C. mexicana group of species. The position of this species suggests that the mostly South American C. thomasi group shares an early ancestor with the C. mexicana group.

  5. At the foot of the shrew: manus morphology distinguishes closely-related Cryptotis goodwini and Cryptotis griseoventris (Mammalia: Soricidae) in Central America

    USGS Publications Warehouse

    Woodman, Neal; Stephens, Ryan B.

    2010-01-01

    Small-eared shrews (Mammalia, Soricidae) of the New World genus Cryptotis are distributed from eastern North America to the northern Andes of South America. One well-defined clade in this genus is the Central American Cryptotis mexicana group, whose members are set off from other species in the genus by their variably broader fore feet and more elongate and broadened fore claws. Two species in the C. mexicana group, Cryptotis goodwini Jackson and Cryptotis griseoventris Jackson, inhabit highlands in Guatemala and southern Mexico and are presumed to be sister species whose primary distinguishing feature is the larger body size of C. goodwini. To better characterize these species and confirm the identification of recently-collected specimens, we obtained digital X-ray images of the manus from large series of dried skins of both species. Measurements of the metacarpals and phalanges successfully separated most specimens of C. goodwini and C. griseoventris. These measurements also show that the fore feet of C. griseoventris from Chiapas, Mexico, are morphologically distinct from those of members of the species inhabiting Guatemala. Univariate, bivariate, and multivariate analyses indicate that fore foot characters are more conservative within species of the C. mexicana group than are cranio-mandibular characters. Patterns of evolution of fore foot characters that superficially appear to be linear gradations are actually more complex, illustrating individual evolutionary trajectories.

  6. Patterns of morphological variation amongst semifossorial shrews in the highlands of Guatemala, with the description of a new species (Mammalia, Soricomorpha, Soricidae)

    USGS Publications Warehouse

    Woodman, Neal

    2011-01-01

    Members of the Cryptotis goldmani group of small-eared shrews (Mammalia, Soricomorpha, Soricidae) represent a clade within the genus that is characterized by modifications of the forelimb that include broadened forefeet, elongated and broadened foreclaws, and massive humeri with enlarged processes. These modifications are consistent with greater adaptation to their semifossorial habits than other members of the genus. The species in this group occur discontinuously in temperate highlands from southern Tamaulipas, Mexico, to Honduras. In Guatemala, there are three species: the relatively widespread Cryptotis goodwini and two species (Cryptotis lacertosus, Cryptotis mam) endemic to highland forests in the Sierra de los Cuchumatanes of western Guatemala. Ongoing studies focusing on the relationships of variation in cranial and postcranial skeletal morphology have revealed a fourth species from remnant cloud forest in the Sierra de Yalijux, central Guatemala. In this paper, I describe this new species and characterize its morphology relative to other species in the C. goldmani group and to other species of Cryptotis in Guatemala. In addition, I summarize available details of its habitat and ecology.

  7. A new species of small-eared shrew from Colombia and Venezuela (Mammalia: Soricomorpha: Soricidae: Genus Cryptotis)

    USGS Publications Warehouse

    Woodman, N.

    2002-01-01

    Populations of small-eared shrews inhabiting the northern Cordillera Oriental of Colombia and adjoining Venezuelan highlands in the vicinity of Paramo de Tama have been referred alternatively to Cryptotis thomssi or Cryptotis meridensis. Morphological and morphometrical study of this population indicates that it belongs to neither taxon, but represents a distinct, previously unrecognized species. I describe this new species as Cryptotis tamensis and redescribe C. meridensis. Recognition of the population at Paramo de Tama as a separate taxon calls into question the identities of populations of shrews currently represented only by single specimens from Cerro Pintado in the Sierra de Perija, Colombia, and near El Junquito in the coastal highlands of Venezuela.

  8. A new small-eared shrew of the Cryptotis nigrescens-group from Colombia (Mammalia: Soricomorpha: Soricidae)

    USGS Publications Warehouse

    Woodman, N.

    2003-01-01

    Cryptotis colombiana Woodman & Timm, 1993 previously was known from few specimens from two isolated regions in the Cordillera Central and Cordillera Oriental of Colombia. Recent collecting in the northern Cordillera Central and review of older collections from the central Cordillera Oriental in the vicinity of Bogota yielded additional specimens that permit reevaluation of the two geographic populations of these small-eared shrews. Morphological and morphometrical studies indicate that the population inhabiting the Cordillera Oriental represents a distinct, previously unrecognized species that I describe herein as Cryptotis brachyonyx. Study of 54 specimens of shrews from the Cordillera Oriental in systematic collections in North America, South America, and Europe yielded only four specimens of the new species, all collected before 1926. The paucity of modern specimens suggests that C. brachyonyx may be extremely restricted in distribution, or possibly extinct.

  9. Biogeographic origin and radiation of the Old World crocidurine shrews (Mammalia: Soricidae) inferred from mitochondrial and nuclear genes.

    PubMed

    Dubey, Sylvain; Salamin, Nicolas; Ruedi, Manuel; Barrire, Patrick; Colyn, Marc; Vogel, Peter

    2008-09-01

    The crocidurine shrews include the most speciose genus of mammals, Crocidura. The origin and evolution of their radiation is, however, poorly understood because of very scant fossil records and a rather conservative external morphology between species. Here, we use an alignment of 3560 base pairs of mitochondrial and nuclear DNA to generate a phylogenetic hypothesis for the evolution of Old World shrews of the subfamily Crocidurinae. These molecular data confirm the monophyly of the speciose African and Eurasian Crocidura, which also includes the fossorial, monotypic genus Diplomesodon. The phylogenetic reconstructions give further credit to a paraphyletic position of Suncus shrews, which are placed into at least two independent clades (one in Africa and sister to Sylvisorex and one in Eurasia), at the base of the Crocidura radiation. Therefore, we recommend restricting the genus Suncus to the Palaearctic and Oriental taxa, and to consider all the African Suncus as Sylvisorex. Using molecular dating and biogeographic reconstruction analyses, we suggest a Palaearctic-Oriental origin for Crocidura dating back to the Upper Miocene (6.8 million years ago) and several subsequent colonisations of the Afrotropical region by independent lineages of Crocidura. PMID:18657625

  10. Fossil shrews from Honduras and their significance for late glacial evolution in body size (Mammalia: Soricidae: Cryptotis)

    USGS Publications Warehouse

    Woodman, N.; Croft, D.A.

    2005-01-01

    Our study of mammalian remains excavated in the 1940s from McGrew Cave, north of Copan, Honduras, yielded an assemblage of 29 taxa that probably accumulated predominantly as the result of predation by owls. Among the taxa present are three species of small-eared shrews, genus Cryptotis. One species, Cryptotis merriami, is relatively rare among the fossil remains. The other two shrews, Cryptotis goodwini and Cryptotis orophila, are abundant and exhibit morpho metrical variation distinguishing them from modern populations. Fossils of C. goodwini are distinctly and consistently smaller than modern members of the species. To quantify the size differences, we derived common measures of body size for fossil C. goodwini using regression models based on modern samples of shrews in the Cryptotis mexicana-group. Estimated mean length of head and body for the fossil sample is 72-79 mm, and estimated mean mass is 7.6-9.6 g. These numbers indicate that the fossil sample averaged 6-14% smaller in head and body length and 39-52% less in mass than the modern sample and that increases of 6-17% in head and body length and 65-108% in mass occurred to achieve the mean body size of the modern sample. Conservative estimates of fresh (wet) food intake based on mass indicate that such a size increase would require a 37-58% increase in daily food consumption. In contrast to C. goodwini, fossil C. orophila from the cave is not different in mean body size from modern samples. The fossil sample does, however, show slightly greater variation in size than is currently present throughout the modern geographical distribution of the taxon. Moreover, variation in some other dental and mandibular characters is more constrained, exhibiting a more direct relationship to overall size. Our study of these species indicates that North American shrews have not all been static in size through time, as suggested by some previous work with fossil soricids. Lack of stratigraphic control within the site and our failure to obtain reliable radiometric dates on remains restrict our opportunities to place the site in a firm temporal context. However, the morphometrical differences we document for fossil C. orophila and C. goodwini show them to be distinct from modern populations of these shrews. Some other species of fossil mammals from McGrew Cave exhibit distinct size changes of the magnitudes experienced by many northern North American and some Mexican mammals during the transition from late glacial to Holocene environmental conditions, and it is likely that at least some of the remains from the cave are late Pleistocene in age. One curious factor is that, whereas most mainland mammals that exhibit large-scale size shifts during the late glacial/postglacial transition experienced dwarfing, C. goodwini increased in size. The lack of clinal variation in modern C. goodwini supports the hypothesis that size evolution can result from local selection rather than from cline translocation. Models of size change in mammals indicate that increased size, such as that observed for C. goodwini, are a likely consequence of increased availability of resources and, thereby, a relaxation of selection during critical times of the year.

  11. Distributional records of shrews (Mammalia, Soricomorpha, Soricidae) from Northern Central America with the first record of Sorex from Honduras

    USGS Publications Warehouse

    Woodman, Neal; Matson, John O.; McCarthy, Timothy J.; Eckerlin, Ralph P.; Bulmer, Walter; Ordonez-Garza, Nicte

    2012-01-01

    Short term surveys for small mammals in Guatemala and Honduras during 1992–2009 provided important new records for 12 taxa of shrews from 24 localities. These locality records expand the known geographic distributions for five species and for the genus Sorex Linnaeus, 1758: the geographic range of Cryptotis goodwini Jackson, 1933, now includes the Sierra de las Minas, Guatemala, and several isolated highlands in western Honduras; the known distribution of Cryptotis mayensis (Merriam, 1901) is increased with the first definite modern record for this shrew from Guatemala; Cryptotis merriami Choate, 1970, is now known to occur in the Sierra de las Minas and the Sierra del Merendon, Guatemala, as well as the isolated Sierra de Omoa and Montana de La Muralla in Honduras, and its documented elevational range (600–1720 m) is expanded; records of Sorex veraepacis Alston, 1877, expand the known distribution of this species to include the Sierra de Yalijux, Guatemala; and discovery of Sorex salvini Merriam, 1897, at Celaque, Honduras (1825–3110 m), represents a considerable extension of the geographic range of the species, and it is the first record of the genus Sorex from Honduras. In addition, the first record of potential syntopy among C. goodwini, C merriami, and Cryptotis orophilus (J.A. Allen, 1895), is reported at an elevation of 1430 m in the Sierra de Celaque, Honduras. Information associated with these records contributes substantially to knowledge of habitat use, elevational distributions, reproductive patterns, diet, and parasites of the species encountered. General patterns include the first evidence that Neotropical species of soricids have smaller litters than their temperate congeners.

  12. The complete mitogenome of Chinese Mole Shrew, Anourosorex squamipes (Soricidae).

    PubMed

    Li, Qun; Wang, Qiong; Chen, Guiying; Fu, Changkun; Chen, Shunde

    2016-01-01

    The Chinese Mole Shrew, Anourosorex squamipes belongs to the family Soricidae, and widely distributes in central and southern China, northern and south Burma, east India, northern Vietnam and Thailand. In this study, the complete mitochondrial genome sequence of Anourosorex squamipes was determined. The mitogenome is 17,121 base pairs in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and 1 control region, with base composition of 34.0% A, 31.3% T, 22.0% C, and 12.7% G. The genome organization, nucleotide composition and codon usage did not differ significantly from those of other shrews. The study contributes to illuminating taxonomic status of Chinese Mole Shrew Anourosorex squamipes. PMID:24708118

  13. The complete mitogenome of Asian House Shrews, Suncus murinus (Soricidae).

    PubMed

    Chen, Shunde; Wei, Haixue; Peng, Hongyuan; Yong, Bin

    2016-03-01

    The Asian House Shrew, Suncus murinus belongs to the family Soricidae, and widely distributes in East, Southeast and South Asia, Southwest Island in the Pacific Ocean and East Africa. In this study, the complete mitochondrial genome sequence of Suncus murinus was determined. The mitogenome is 17,240?bp in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and a control region, with a base composition of 33.0% A, 32.7% T, 21.2% C and 13.1% G. The present study contributes to illuminating taxonomic status of S. murinus, and may facilitate further investigation of the molecular evolution of Soricidae. PMID:24976048

  14. This shrew is a jumping mouse (Mammalia, Dipodidae): Sorex dichrurus Rafinesque 1833 is a synonym of Zapus hudsonius (Zimmermann 1780)

    USGS Publications Warehouse

    Woodman, Neal

    2012-01-01

    Constantine S. Rafinesque described Sorex dichrurus as a shrew in 1833, based on a specimen he found in a proprietary museum near Niagara Falls on the New York/Ontario border. The name subsequently has been ignored by the scientific community. By describing this specimen as a shrew and ascribing it to the genus Sorex, Rafinesque clearly indicated that his species should be considered a member of the taxonomic family now recognized as the Soricidae (Mammalia, Eulipotyphla). Yet, the description of the animal, and its comparison to ‘‘Gerbillus,’’ clearly identify it as a dipodid rodent, specifically Zapus hudsonius (Zimmermann, 1780); S. dichrurus should be treated as a junior subjective synonym of that taxon. Based on its type locality of Goat Island, New York, this name is also a junior synonym of the subspecies Z. hudsonius canadensis (Davies, 1798).

  15. A new species of Cryptotis (Mammalia, Eulipotyphla, Soricidae) from the Sierra de Perijá, Venezuelan-Colombian Andes

    USGS Publications Warehouse

    Quiroga-Carmona, Marcial; Woodman, Neal

    2015-01-01

    The Sierra de Perijá is the northern extension of the Cordillera Oriental of the Andes and includes part of the border between Colombia and Venezuela. The population of small-eared shrews (Mammalia, Eulipotyphla, Soricidae, Cryptotis) inhabiting the Sierra de Perijá previously was known from only a single skull from an individual collected in Colombia in 1989. This specimen had been referred to alternatively as C. thomasi and C. meridensis, but more precise definition of the known Colombian and Venezuelan species of Cryptotis has since excluded the Sierra de Perijá population from any named species. The recent collection of a specimen from the Venezuelan slope of Sierra de Perijá, prompted us to re-evaluate the taxonomic status of this population and determine its relationship with other Andean shrews. Our examination of the available specimens revealed that they possess a unique suite of morphological and morphometrical characters, and we describe the Sierra de Perijá population as a new species in the South American C. thomasi species group. Recognition of this new species adds to our knowledge of this genus in South America and to the biodiversity of the Sierra de Perijá.

  16. The complete mitogenome of Stripe-Backed Shrew, Sorex cylindricauda (Soricidae).

    PubMed

    Chen, Shunde; Tu, Feiyun; Zhang, Xiuyue; Li, Wei; Chen, Guiying; Zong, Hao; Wang, Qiong

    2015-06-01

    The Stripe-Backed Shrew, Sorex cylindricauda belongs to the family Soricidae, and distributes in northwestern Yunnan, central Sichuan, southern Gansu and Shaanxi. In this study, the complete mitochondrial genome sequence of S. cylindricauda was determined. The mitogenome is 17,191?bp in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 control region, with a base composition of 33.2% A, 30.2% T, 23.8% C and 12.8% G. The study contributes to illuminating taxonomic status of Stripe-Backed Shrew Sorex cylindricauda. PMID:24409903

  17. The Stephen H. Long Expedition (1819?1820), Titian R. Peale?s field illustrations, and the lost holotypes of the North American shrews Sorex brevicaudus Say and Sorex parvus Say (Mammalia: Soricidae) from the Philadelphia Museum

    USGS Publications Warehouse

    Woodman, N.

    2009-01-01

    While encamped for the winter of 1819?1820 at Engineer Cantonment along the Missouri River in present-day eastern Nebraska, members of Major Stephen Harriman Long?s Expedition to the Rocky Mountains collected a number of animals that were previously unknown. Among the mammals were two soricids that were subsequently described by Thomas Say as Sorex brevicaudus (Northern Short-tailed Shrew, Blarina brevicauda) and Sorex parvus (Least Shrew, Cryptotis parvus). The holotypes of these species were deposited and placed on public exhibit in the Philadelphia Museum, the predominant North American systematic collection of the early nineteenth century. Like most private museums of that era, the Philadelphia Museum eventually went out of business, and its collections were dispersed and, for the most part, lost. Fortunately, Titian R. Peale made a detailed field sketch of the two specimens soon after their capture and subsequently executed a watercolor based on that sketch. In addition, an engraving of the holotypes was published in the decade following the discovery of the two species. Illustrations of holotypes are taxonomically useful when they depict diagnostic characters of species. They take on added taxonomic significance in the absence of the holotypes. In the cases of Sorex brevicaudus and Sorex parvus, pictures provide strong confirmation of the taxonomic identities of these two species, as well as recording the early history of the specimens.

  18. Two new species of shrews (Soricidae) from the western highlands of Guatemala

    USGS Publications Warehouse

    Woodman, Neal

    2010-01-01

    The broad-clawed shrews (Soricomorpha: Soricidae: Cryptotis) encompass a clade of 5 speciesCryptotis alticolus (Merriam), C. goldmani (Merriam), C. goodwini Jackson, C. griseoventris Jackson, and C. peregrinus (Merriam)that is known collectively as the Cryptotis goldmani group and is characterized by broadened forefeet, elongated and broadened fore claws, and broadened humeri. These shrews are distributed in highland regions from central Mexico to Honduras. Two broad-clawed shrews, C. goodwini and C. griseoventris, occur in southern Mexico and Guatemala and are presumed sister species whose primary distinguishing feature is the larger size of C. goodwini. In an investigation of variation within and between these 2 species, I studied characteristics of the postcranial skeleton. Statistical analyses of a variety of character suites indicate that the forelimb morphology in this group exhibits less intraspecific variation and greater interspecific variation than cranio-mandibular morphology, although most skull characters support groupings based on forelimb characters. Together, these characters define 4 distinct groups among the specimens examined. C. griseoventris is restricted to the northern highlands of Chiapas, Mexico, and C. goodwini occurs in the southern highlands of Chiapas and Guatemala. Herein, I describe 2 new species of broad-clawed shrews from the Sierra de los Cuchumatanes, Guatemala.

  19. Unique regulation of thyroid hormone metabolism during fasting in the house musk shrew (Suncus murinus, Insectivora: Soricidae).

    PubMed

    Takeuchi, Yoko; Suzuki, Daisuke; Oda, Sen-Ichi; Refetoff, Samuel; Seki, Koji; Tsunekawa, Katsuhiko; Kasahara, Takayuki; Murakami, Masami; Murata, Yoshiharu

    2006-05-01

    The active hormone, 3,3',5-triiodothyronine (T3) is derived from thyroxine (T4) by the action of iodothyronine 5'-deiodinases (5'-D). By now two types of 5'-D have been identified; Type 1 (D1) and type 2 (D2). A relative contribution of these isotypes to the circulating T3 levels in the human remains to be determined whereas a number of reports indicate that, under physiological conditions, D1 plays a major role in maintaining circulating T3 levels in rodents. In both human and rodents, sickness and starvation reduce serum T3 concentration mainly through decrease in D1 activity. Recently, we found that the house musk shrew (Suncus murinus, Insectivora: Soricidae) has a different tissue distribution of D1 activity. Because compared to rodents D1 activity in the shrew was found only in liver at a much reduced level, D2 rather than D1 may play a role in the maintenance of serum T3. Therefore, we questioned how D1 and D2 activities change in fasted shrews and how these changes affect circulating thyroid hormone levels. We thus starved shrews for 24, 48 or 72 h and measured changes in serum concentration of T3, T4, and 3,3',5'-triiodothyronine (reverse T3, rT3) and D1 activities as well as its mRNA expression in liver. D2 activities were also measured in brown adipose tissue (BAT) and cerebral cortex of shrews. Unlike in human and rodents, T3 levels in shrews remained constant during fasting while T4 levels tended to decrease, resulting in an increase in its T3/T4 ratio. On the other hand, changes in rT3 levels were similar to those in human and rodents, being elevated with fasting. D1 mRNA and its activity were significantly reduced in the liver whereas D2 activities in BAT and cerebral cortex were increased by fasting. These results indicated that fasting in shrews also reduced hepatic D1 activity but it did not affect circulating T3 levels. The increased T3/T4 ratio together with increased D2 activity in BAT and cerebral cortex with fasting suggest that D2 rather than D1 is responsible for the maintenance of T3 levels in the house musk shrew. PMID:16426605

  20. Molecular Phylogeny Supports Repeated Adaptation to Burrowing within Small-Eared Shrews Genus of Cryptotis (Eulipotyphla, Soricidae)

    PubMed Central

    He, Kai; Woodman, Neal; Boaglio, Sean; Roberts, Mariel; Supekar, Sunjana; Maldonado, Jesús E.

    2015-01-01

    Small-eared shrews of the New World genus Cryptotis (Eulipotyphla, Soricidae) comprise at least 42 species that traditionally have been partitioned among four or more species groups based on morphological characters. The Cryptotis mexicana species group is of particular interest, because its member species inhibit a subtly graded series of forelimb adaptations that appear to correspond to locomotory behaviors that range from more ambulatory to more fossorial. Unfortunately, the evolutionary relationships both among species in the C. mexicana group and among the species groups remain unclear. To better understand the phylogeny of this group of shrews, we sequenced two mitochondrial and two nuclear genes. To help interpret the pattern and direction of morphological changes, we also generated a matrix of morphological characters focused on the evolutionarily plastic humerus. We found significant discordant between the resulting molecular and morphological trees, suggesting considerable convergence in the evolution of the humerus. Our results indicate that adaptations for increased burrowing ability evolved repeatedly within the genus Cryptotis. PMID:26489020

  1. The complete mitogenome of Asiatic Short-tailed Shrew Blarinella quadraticauda (Soricidae).

    PubMed

    Wang, Qiong; Fu, Changkun; Chen, Shunde; Yong, Bin; Chen, Guiying; Zong, Hao

    2016-01-01

    The Asiatic Short-tailed Shrew, Blarinella quadraticauda, is an endemic shrew to China, and is only distributed in Sichuan. In this study, the complete mitochondrial genome sequence of B. quadraticauda was determined. The mitogenome is 17,014 base pairs in length and contains 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 control region, with a base composition of 33.3 % A, 31.8% T, 22.3% C and 12.6% G. This study contributes to illuminating taxonomic status of the Asiatic Short-tailed Shrew, B. quadraticauda. PMID:24660918

  2. Persistence and diversification of the Holarctic shrew, Sorex tundrensis (Family Soricidae), in response to climate change.

    PubMed

    Hope, Andrew G; Waltari, Eric; Fedorov, Vadim B; Goropashnaya, Anna V; Talbot, Sandra L; Cook, Joseph A

    2011-10-01

    Environmental processes govern demography, species movements, community turnover and diversification and yet in many respects these dynamics are still poorly understood at high latitudes. We investigate the combined effects of climate change and geography through time for a widespread Holarctic shrew, Sorex tundrensis. We include a comprehensive suite of closely related outgroup taxa and three independent loci to explore phylogeographic structure and historical demography. We then explore the implications of these findings for other members of boreal communities. The tundra shrew and its sister species, the Tien Shan shrew (Sorex asper), exhibit strong geographic population structure across Siberia and into Beringia illustrating local centres of endemism that correspond to Late Pleistocene refugia. Ecological niche predictions for both current and historical distributions indicate a model of persistence through time despite dramatic climate change. Species tree estimation under a coalescent process suggests that isolation between populations has been maintained across timeframes deeper than the periodicity of Pleistocene glacial cycling. That some species such as the tundra shrew have a history of persistence largely independent of changing climate, whereas other boreal species shifted their ranges in response to climate change, highlights the dynamic processes of community assembly at high latitudes. PMID:21919986

  3. Persistence and diversification of the Holarctic shrew, Sorex tundrensis (Family Soricidae), in response to climate change

    USGS Publications Warehouse

    Hope, Andrew G.; Waltari, Eric; Fedorov, V.B.; Goropashnaya, A.V.; Talbot, Sandra; Cook, Joseph A.

    2014-01-01

    Environmental processes govern demography, species movements, community turnover and diversification and yet in many respects these dynamics are still poorly understood at high latitudes. We investigate the combined effects of climate change and geography through time for a widespread Holarctic shrew, Sorex tundrensis. We include a comprehensive suite of closely related outgroup taxa and three independent loci to explore phylogeographic structure and historical demography. We then explore the implications of these findings for other members of boreal communities. The tundra shrew and its sister species, the Tien Shan shrew (Sorex asper), exhibit strong geographic population structure across Siberia and into Beringia illustrating local centres of endemism that correspond to Late Pleistocene refugia. Ecological niche predictions for both current and historical distributions indicate a model of persistence through time despite dramatic climate change. Species tree estimation under a coalescent process suggests that isolation between populations has been maintained across timeframes deeper than the periodicity of Pleistocene glacial cycling. That some species such as the tundra shrew have a history of persistence largely independent of changing climate, whereas other boreal species shifted their ranges in response to climate change, highlights the dynamic processes of community assembly at high latitudes.

  4. Persistence and diversification of the Holarctic shrew, Sorex tundrensis (Family Soricidae), in response to climate change

    USGS Publications Warehouse

    Hope, A.G.; Waltari, Eric; Fedorov, V.B.; Goropashnaya, A.V.; Talbot, S.L.; Cook, J.A.

    2011-01-01

    Environmental processes govern demography, species movements, community turnover and diversification and yet in many respects these dynamics are still poorly understood at high latitudes. We investigate the combined effects of climate change and geography through time for a widespread Holarctic shrew, Sorex tundrensis. We include a comprehensive suite of closely related outgroup taxa and three independent loci to explore phylogeographic structure and historical demography. We then explore the implications of these findings for other members of boreal communities. The tundra shrew and its sister species, the Tien Shan shrew (Sorex asper), exhibit strong geographic population structure across Siberia and into Beringia illustrating local centres of endemism that correspond to Late Pleistocene refugia. Ecological niche predictions for both current and historical distributions indicate a model of persistence through time despite dramatic climate change. Species tree estimation under a coalescent process suggests that isolation between populations has been maintained across timeframes deeper than the periodicity of Pleistocene glacial cycling. That some species such as the tundra shrew have a history of persistence largely independent of changing climate, whereas other boreal species shifted their ranges in response to climate change, highlights the dynamic processes of community assembly at high latitudes. ?? 2011 Blackwell Publishing Ltd.

  5. [Description of Hymenolepis cerberensis n. sp. (Cestoda: Hymenolepididae) and first general considerations on the fauna of cestode parasites of the pygmy shrew Suncus etruscus (Savi, 1822) (Insectivora: Soricidae)].

    PubMed

    Mas-Coma, S; Fons, R; Galan-Puchades, M T; Valero, M A

    1986-01-01

    Description and differentiation of the adult stage of Hymenolepis cerberensis n. sp. (Cestoda: Hymenolepididae), an intestinal parasite of the Pygmy white-toothed shrew, Suncus etruscus (Savi, 1822) (Insectivora: Soricidae: Crocidurinae) in the region of Banyuls-sur-Mer and Cerbre (Oriental Pyrenees, France). The new species is characterized by the size of the gravid specimens and by the presence of 18-21 rostellar hooks of 18.5-20 micron and of filaments around the embryophore. The general composition of the fauna of Cyclophyllidea parasitizing S. etruscus is analysed. There are three less specialised Hymenolepis species with a scolex of the same type and one Pseudhymenolepis species, with the absence of unarmed species lacking a rostrum. The oioxenous character of the Cestodes parasitizing Suncus species sustains the validity of the genus Suncus. The resemblance of the Cestodefaunas suggests a narrow phyletic relationship between the genera Suncus and Crocidura. PMID:3813424

  6. A new species of small-eared shrew (Mammalia, Eulipotyphla, Cryptotis) from the Lacandona rain forest, Mexico

    USGS Publications Warehouse

    Guevara, Lázaro; Sánchez-Cordero, Víctor; León-Paniagua, Livia; Woodman, Neal

    2014-01-01

    The diversity and distribution of mammals in the American tropics remain incompletely known. We describe a new species of small-eared shrew (Soricidae, Cryptotis) from the Lacandona rain forest, Chiapas, southern Mexico. The new species is distinguished from other species of Cryptotis on the basis of a unique combination of pelage coloration, size, dental, cranial, postcranial, and external characters, and genetic distances. It appears most closely related to species in the Cryptotis nigrescens species group, which occurs from southern Mexico to montane regions of Colombia. This discovery is particularly remarkable because the new species is from a low-elevation habitat (approximately 90 m), whereas most shrews in the region are restricted to higher elevations, typically > 1,000 m. The only known locality for the new shrew is in one of the last areas in southern Mexico where relatively undisturbed tropical vegetation is still found. The type locality is protected by the Mexican government as part of the Yaxchilán Archaeological Site on the border between Mexico and Guatemala.

  7. Natural hybridization between extremely divergent chromosomal races of the common shrew (Sorex araneus, Soricidae, Soricomorpha): hybrid zone in European Russia.

    PubMed

    Bulatova, N; Jones, R M; White, T A; Shchipanov, N A; Pavlova, S V; Searle, J B

    2011-03-01

    The Moscow and Seliger chromosomal races of the common shrew differ by Robertsonian fusions and possibly whole-arm reciprocal translocations (WARTs) such that their F? hybrids produce a chain-of-eleven configuration at meiosis I and are expected to suffer substantial infertility. Of numerous hybrid zones that have been described in the common shrew, those between the Moscow and Seliger races involve the greatest chromosomal difference. We collected 211 individuals from this zone to generate a total dataset of 298 individuals from 187 unique global positioning system (GPS) locations within the vicinity of interracial contact. We used a geographic information system (GIS) to map the location of the hybrid zone, which follows a direct route between two lakes, as would be anticipated from tension zone theory. Even within the central area of the hybrid zone, there is a much higher frequency of pure race individuals than hybrid, making this a clear example of a bimodal zone in the sense of Jiggins & Mallet (2000). The zone runs through good habitat for common shrews, but nevertheless it is very narrow (standard cline widths: 3-4 km), as would be anticipated from low hybrid fitness. There is clear potential for an interruption to gene flow and build-up of reproductive isolation. As found in some other hybrid zones, there is a high frequency of novel genetic variants, in this case, new chromosomal rearrangements. Here, we report a de novo Robertsonian fission and a de novo reciprocal translocation, both for the first time in the common shrew. There is an extraordinarily high frequency of de novo mutations recorded in F? hybrids in the zone and we discuss how chromosomal instability may be associated with such hybrids. The occurrence of a de novo Robertsonian fission is of considerable significance because it provides missing evidence that fissions are the basis of the novel acrocentric forms found and apparently selected for in certain common shrew hybrid zones. PMID:21159004

  8. Eimeria cryptotis n. sp. (Apicomplexa: Eimeriidae) from the least shrew, Cryptotis parva (Insectivora: Soricidae), in north-central Texas.

    PubMed

    McAllister, C T; Upton, S J

    1989-04-01

    From March through November 1987, 14 least shrews, Cryptotis parva (Say), were collected in portions of north-central Texas and examined for coccidian parasites; only 1 (7.1%) was found to be passing oocysts. Eimeria cryptotis n. sp. is described herein as new and represents the only coccidian reported thus far from C. parva. Sporulated oocysts are subspherical, 16.4 x 15.3 (14-18 x 13-17) microns; shape index 1.1 (1.0-1.2) microns. A micropyle and oocyst residuum are absent, but a polar granule is present. The sporocysts are ovoid, 10.6 x 7.0 (9-11 x 6-8) microns; shape index 1.5 (1.4-1.8) microns. Stieda and substieda bodies and a sporocyst residuum are present. The sporozoites are elongate and only 2 could be observed well enough to measure (11.2 x 2.4 and 8.8 x 2.4 microns) because they are normally obscured by the sporocyst residuum. Sporozoites lack refractile bodies and contain a centrally located nucleus. The new species can be distinguished from the majority of insectivore coccidia on the basis of oocyst size. PMID:2926589

  9. The identity of the enigmatic "Black Shrew" (Sorex niger Ord, 1815)

    USGS Publications Warehouse

    Woodman, Neal

    2013-01-01

    The scientific name Sorex niger Ord, 1815 (Mammalia, Soricidae) was originally applied to a North American species that George Ord called the Black Shrew. The origin of the name Black Shrew, however, was obscure, and Samuel Rhoads subsequently wrote that the species represented by this name could not be determined. The names Sorex niger Ord and Black Shrew have since been mostly forgotten. Two of Ord's contemporaries, however, noted that Ord's use of these names probably alluded to Benjamin Smith Barton's Black Shrew, whose discovery near Philadelphia was announced by Barton in 1806. Examination of two unpublished illustrations of the Black Shrew made by Barton indicates that the animal depicted is Blarina brevicauda (Say, 1822). Had the connection between Ord's and Barton's names been made more clearly, one of the most common mammals in eastern North America would bear a different scientific name today. This connection also would have affected the validity of Sorex niger Horsfield, 1851. While Sorex niger Ord remains a nomen nudum, the animal it referenced can now be identified.

  10. First evidence of poisonous shrews with an envenomation apparatus

    NASA Astrophysics Data System (ADS)

    Cuenca-Bescs, Gloria; Rofes, Juan

    2007-02-01

    Herein, we report evidence of an envenomation apparatus (EA) in two different species of extinct giant shrews, Beremendia and an indeterminate soricine (Mammalia, Eulipotyphla, Soricidae), documented by very well preserved fossil specimens recovered from two Early Pleistocene cave deposits of the Sierra de Atapuerca in Burgos, Spain. The two soricine taxa from Atapuerca have evolved specialized teeth as EAs, which differ from those of recently reported mammals of the Paleocene age, being more similar to the ones described in the modern Solenodon. This discovery reveals the first instance of shrews possessing what appears to be an EA, an evolutionary adaptation that, in these species, was probably related to an increase in body mass and hunting of a larger-sized prey. The Atapuerca specimens would have a highly specialized EA, one of the very few reported for an extinct or living mammal of any time. In addition to the presence of a gutter-like groove along the medial side of the crown of the lower incisors, these two species also present stout jaws and a modified mandibular symphysis with a conspicuous cavity, which in life would likely contain large amounts of connective tissue. The strong mandible architecture of these large shrews would be, in this way, reinforced by a more immovable symphysis, increasing the bite force exerted over a potential prey. This adaptation, together with the grooved incisors, would ensure a rapid and efficient transmission of the poisonous saliva to paralyze relatively large-sized prey.

  11. White-toothed shrews (Mammalia, Soricomorpha, Crocidura) of coastal islands of Vietnam

    PubMed Central

    Abramov, Alexei V.; Bannikova, Anna A.; Rozhnov, Viatcheslav V.

    2012-01-01

    Abstract New findings of the white-toothed shrews (Crocidura spp.) from offshore islands of Vietnam are reported. The species identifications have been confirmed by the analysis of complete mitochondrial cytochrome b gene (1140 bp). Crocidura phuquocensis is the only species found in the Phu Quoc Island. Crocidura fuliginosa has been recorded from two islands of the Con Dao Archipelago (Con Son and Bai Canh). The occurrence of Crocidura fuliginosa in Vietnam has been genetically confirmed for the first time. Crocidura attenuata has been collected from the Cat Ba Island for the first time, and this finding corresponds well with the proposal that the species distribution is confined to the north and east of the Red River only. PMID:22855639

  12. [Respiratory function of blood and relative weight of certain organs in two species of shrew: Crocidura russula and Suncus etruscus (Soricidae mammals)].

    PubMed

    Bartels, H; Bartels, R; Baumann, R; Fons, R; Jrgens, K D; Wright, P

    1978-04-24

    A high oxygen capacity combined with a low oxygen affinity and a large Bohr effect achieve a high oxygen transport capacity in small shrews. The high metabolic rate (Suncus estruscus: 100 to 350 ml O2/kg. min) can be explained by the combination of the favorable blood parameters with a high relative heart weight (1,2% of body weight) and heart frequencies of 1,000 to 1,350 per minute. PMID:27314

  13. Contraction parameters, myosin composition and metabolic enzymes of the skeletal muscles of the etruscan shrew Suncus etruscus and of the common European white-toothed shrew Crocidura russula (Insectivora: soricidae).

    PubMed

    Peters, T; Kubis, H P; Wetzel, P; Sender, S; Asmussen, G; Fons, R; Jrgens, K D

    1999-09-01

    In the Etruscan shrew, the isometric twitch contraction times of extensor digitorum longus (EDL) and soleus muscles are shorter than in any other mammal, allowing these muscles to contract at outstandingly high contraction frequencies. This species has the highest mass-specific metabolic rate of all mammals and requires fast skeletal muscles not only for locomotion but also for effective heat production and for an extremely high ventilation rate. No differences could be detected in the fibre type pattern, the myosin heavy and light chain composition, or in the activity of the metabolic enzymes lactate dehydrogenase and citrate synthase of the two limb muscles, the EDL and the soleus, which in larger mammalian species exhibit distinct differences in contractile proteins and metabolic enzymes. All properties determined in EDL and soleus muscles of Suncus etruscus, as well as in the larger Crocidura russula, are typical for fast-oxidative fibres, and the same holds for several other skeletal muscles including the diaphragm muscle of S. etruscus. Nevertheless, the EDL and soleus muscles showed different mechanical properties in the two shrew species. Relaxation times and, in C. russula, time to peak force are shorter in the EDL than in the soleus muscle. This is in accordance with the time course of the Ca(2+) transients in these muscles. Such a result could be due to different parvalbumin concentrations, to a different volume fraction of the sarcoplasmic reticulum in the two muscles or to different Ca(2+)-ATPase activities. Alternatively, the lower content of cytosolic creatine kinase (CK) in the soleus compared with the EDL muscle could indicate that the observed difference in contraction times between these shrew muscles is due to the CK-controlled activity of their sarcoplasmic reticulum Ca(2+)-ATPase. PMID:10460733

  14. Hand development and sequence of ossification in the forelimb of the European shrew Crocidura russula (Soricidae) and comparisons across therian mammals

    PubMed Central

    Prochel, Jan; Vogel, Peter; Snchez-Villagra, Marcelo R

    2004-01-01

    Hand development in the European shrew Crocidura russula is described, based on the examination of a cleared and double-stained ontogenetic series and histological sections of a c. 20-day-old embryo and a neonate. In the embryo all carpal elements are still mesenchymal condensations, and there are three more elements than in the adult stage: the lunatum, which fuses with the scaphoid around birth; a centrale, which either fuses with another carpal element or just disappears later in ontogeny; and the anlage of an element that later fuses with the radius. Carpal arrangement in the neonate and the adult is the same. In order to compare the relative timing of the onset of ossification in forelimb bones in C. russula with that of other therians, we built up two matrices of events based on two sets of data and used the event-pair method. In the first analysis, ossification of forelimb elements in general was examined, including that of the humerus, radius, ulna, the first carpal and metacarpal to ossify, and the phalanges of the third digit. The second analysis included each carpal, humerus, radius, ulna, the first metacarpal and the first phalanx to ossify. Some characters (= eventpairs) provide synapomorphies for some clades examined. There have been some shifts in the timing of ossification apparently not caused by ecological and/or environmental influences. In two species (Oryctolagus and Myotis), there is a tendency to start the ossification of the carpals relatively earlier than in all other species examined, the sauropsid outgroups included. PMID:15291793

  15. [Genetic Structure of the Common Shrew Sorex araneus L. 1758 (Mammalia, Lipotyphla) in Continuous and Fragmented Areas].

    PubMed

    Grigoryeva, O O; Borisova, Yu M; Stakheev, V V; Balakirev, A E; Krivonogov, D M; Orlov, V N

    2015-06-01

    In this work the genetic variability of the common shrew populations Sorex araneus L. in Eastern Europe was studied via sequencing of the mitochondrial gene cyt b. A total of 82 sequences of the mitochondrial gene cyt b with a length of 953 basepairs were analyzed, including five chromosome races in a continuous area of the species in forest zone and two races in fragmented area in the steppe zone. Phylogeographic subdivision of the common shrew was not expressed, and there was no significant correlation between genetic and geographic distances in continuous areas. We did not acquire convincing evidence of the influence of narrow hybrid zones between chromosome races on the flow of neutral alleles. A significant p-distance (0.69 0.27%) of geographically close populations of the chromosome race Neroosa indicates the formation of the karyotype of this race in the Pliocene or Pleistocene. In our work, the phylogeographic structure was determined more by species area fragmentation than by its karyotypic features. PMID:26310034

  16. Phylogeny and Taxonomy of the Round-Eared Sengis or Elephant-Shrews, Genus Macroscelides (Mammalia, Afrotheria, Macroscelidea)

    PubMed Central

    Dumbacher, John P.; Rathbun, Galen B.; Smit, Hanneline A.; Eiseb, Seth J.

    2012-01-01

    The round-eared sengis or elephant-shrews (genus Macroscelides) exhibit striking pelage variation throughout their ranges. Over ten taxonomic names have been proposed to describe this variation, but currently only two taxa are recognized (M. proboscideus proboscideus and M. p. flavicaudatus). Here, we review the taxonomic history of Macroscelides, and we use data on the geographic distribution, morphology, and mitochondrial DNA sequence to evaluate the current taxonomy. Our data support only two taxa that correspond to the currently recognized subspecies M. p. proboscideus and M. p. flavicaudatus. Mitochondrial haplotypes of these two taxa are reciprocally monophyletic with over 13% uncorrected sequence divergence between them. PCA analysis of 14 morphological characters (mostly cranial) grouped the two taxa into non-overlapping clusters, and body mass alone is a relatively reliable distinguishing character throughout much of Macroscelides range. Although fieldworkers were unable to find sympatric populations, the two taxa were found within 50 km of each other, and genetic analysis showed no evidence of gene flow. Based upon corroborating genetic data, morphological data, near sympatry with no evidence of gene flow, and differences in habitat use, we elevate these two forms to full species. PMID:22479325

  17. Development and characterization of 21 polymorphic microsatellite markers for the barren-ground shrew, Sorex ugyunak (Mammalia: Sorcidae), through next-generation sequencing, and cross-species amplification in the masked shrew, S. cinereus

    USGS Publications Warehouse

    Sonsthagen, S.A.; Sage, G.K.; Fowler, M.; Hope, A.G.; Cook, J.A.; Talbot, S.L.

    2013-01-01

    We used next generation shotgun sequencing to develop 21 novel microsatellite markers for the barren-ground shrew (Sorex ugyunak), which were polymorphic among individuals from northern Alaska. The loci displayed moderate allelic diversity (averaging 6.81 alleles per locus) and heterozygosity (averaging 70 %). Two loci deviated from Hardy–Weinberg equilibrium (HWE) due to heterozygote deficiency. While the population did not deviate from HWE overall, it showed significant linkage disequilibrium suggesting this population is not in mutation-drift equilibrium. Nineteen of 21 loci were polymorphic in masked shrews (S. cinereus) from interior Alaska and exhibited linkage equilibrium and HWE overall. All loci yielded sufficient variability for use in population studies.

  18. Muscle Aging and Oxidative Stress in Wild-Caught Shrews

    PubMed Central

    Hindle, Allyson G.; Lawler, John M.; Campbell, Kevin L.; Horning, Markus

    2010-01-01

    Red-toothed shrews (Soricidae, subfamily Soricinae) are an intriguing model system to examine the free radical theory of aging in wild mammals, given their short (<18 month) lifespan and high mass-specific metabolic rates. As muscle performance underlies both foraging ability and predator avoidance, any age-related decline should be detrimental to fitness and survival. Muscle samples of water shrews (Sorex palustris) and sympatrically distributed short-tailed shrews (Blarina brevicauda) were therefore assessed for oxidative stress markers, protective antioxidant enzymes and apoptosis. Activity levels of catalase and glutathione peroxidase increased with age in both species. Similarly, Cu,Zn-superoxide dismutase isoform content was elevated significantly in older animals of both species (increases of 60% in the water shrew, 25% in the short-tailed shrew). Only one oxidative stress marker (lipid peroxidation) was age-elevated; the others were stable or declined (4-hydroxynonenal adducts and dihydroethidium oxidation). Glutathione peroxidase activity was significantly higher in the short-tailed shrew, while catalase activity was 2 higher in water shrews. Oxidative stress indicators were on average higher in short-tailed shrews. Apoptosis occurred in <1% of myocytes examined, and did not increase with age. Within the constraints of the sample size we found evidence of protection against elevated oxidative stress in wild-caught shrews. PMID:20109576

  19. Nomenclatural notes and identification of small-eared shrews (Mammalia: genus Cryptotis) from Cobn, Guatemala, in The Natural History Museum, London

    USGS Publications Warehouse

    Woodman, Neal

    2011-01-01

    A small series of shrews collected in Guatemala and registered in the British Museum between 1843 and 1907 includes parts of type series for three species: Corsira tropicalis Gray (1843), Sorex micrurus Tomes (1862), and Blarina tropicalis Merriam (1895). These three names are now considered equivalent, but my recent review of the specimens comprising the series indicates that they include three distinct species: Cryptotis merriami Choate (1970), Cryptotis oreoryctes Woodman (2011), and Cryptotis tropicalis (Merriam 1895). I review the taxonomic history of these specimens, provide current identifications tied directly to museum register numbers, describe how to distinguish the three species, and provide revised synonymies for these species.

  20. Distribution and coexistence of shrews in patchy landscapes: A field test of multiple hypotheses

    NASA Astrophysics Data System (ADS)

    Mortelliti, Alessio; Boitani, Luigi

    2009-11-01

    Despite the important role of shrews (Soricomorpha: Soricidae) in the functioning of ecosystems, as predators and prey, the effects of habitat loss and fragmentation on this guild of mammals are still unclear. We studied the distribution of 5 species (the greater white toothed shrew Crocidura leucodon; the lesser white toothed shrew Crocidura suaveolens; the pigmy shrew Sorex minutus; the Appennine shrew Sorex samniticus and the Etruscan shrew Suncus etruscus) in a fragmented landscape in central Italy. Shrews were trapped with pitfall traps made from plastic water bottles, the number of traps increased with patch size. A total of 170 individuals, of 5 species of shrews were captured. Shrews were widely distributed in our study area, however patch occupancy was determined mainly by vegetation and geometrical characteristics of the patches. Our data supports the hypotheses that patterns of habitat selection and the dynamics of seasonal abundance (habitat and temporal partitioning between similarly sized species) reduce competitive pressure, thus allowing coexistence of shrews in relatively species-rich assemblages, for such small amounts of habitat. The most important outcome of our results is the crucial role played by vegetation structure in determining distribution patterns. These results strongly suggest that measurements of the vegetation structure of habitat patches should always be included as explanatory variables when studying the distribution of shrews in fragmented landscapes.

  1. Life cycle of Renylaima capensis, a brachylaimid trematode of shrews and slugs in South Africa: two-host and three-host transmission modalities suggested by epizootiology and DNA sequencing

    PubMed Central

    2012-01-01

    Background The life cycle of the brachylaimid trematode species Renylaima capensis, infecting the urinary system of the shrew Myosorex varius (Mammalia: Soricidae: Crocidosoricinae) in the Hottentots Holland Nature Reserve, South Africa, has been elucidated by a study of its larval stages, epizootiological data in local snails and mammals during a 34-year period, and its verification with mtDNA sequencing. Methods Parasites obtained from dissected animals were mounted in microscope slides for the parasitological study and measured according to standardized methods. The mitochondrial DNA cox1 gene was sequenced by the dideoxy chain-termination method. Results The slugs Ariostralis nebulosa and Ariopelta capensis (Gastropoda: Arionidae) act as specific first and second intermediate hosts, respectively. Branched sporocysts massively develop in A. nebulosa. Intrasporocystic mature cercariae show differentiated gonads, male terminal duct, ventral genital pore, and usually no tail, opposite to Brachylaimidae in which mature cercariae show a germinal primordium and small tail. Unencysted metacercariae, usually brevicaudate, infect the kidney of A. capensis and differ from mature cercariae by only a slightly greater size. The final microhabitats are the kidneys and ureters of the shrews, kidney pelvis and calyces in light infections and also kidney medulla and cortex in heavy infections. Sporocysts, cercariae, metacercariae and adults proved to belong to R. capensis by analysis of a 437-bp-long cox1 fragment, which was identical except for three mutations in metacercariae, of which only one silent. Epizootiological studies showed usual sporocyst infection in A. nebulosa and very rare metacercarial infection in A. capensis, which does not agree with high prevalences and intensities in the shrews. Conclusions The presence of monotesticular adult forms and larval prevalences and intensities observed suggest that R. capensis may use two transmission strategies, a two-host life cycle by predation of A. nebulosa harbouring intrasporocystic cercariae may be the normal pattern, whereas a second mollusc host is just starting to be introduced. In shrews, a tissue-traversing, intraorganic migration followed by an interorganic migration to reach and penetrate the outer surface of either of both kidneys should occur. For first slug infection, the fluke takes advantage of the phenomenon that M. varius always urinate during defaecation. Consequently, in Brachylaimidae, the second intermediate mollusc host should evolutionarily be seen as a last addition to the cycle and their present adult stage microhabitat restricted to digestive tract and related organs as a loss of the tissue-traversing capacity of the metacercaria. PMID:22889081

  2. Variation in the myosoricine hand skeleton and its implications for locomotory behavior (Eulipotyphla: Soricidae)

    USGS Publications Warehouse

    Woodman, Neal; Stabile, Frank A.

    2015-01-01

    Substrate use and locomotory behavior of mammals are typically reflected in external characteristics of the forefeet, such as the relative proportions of the digits and claws. Although skeletal anatomy of the forefeet can be more informative than external characters, skeletons remain rare in systematic collections. This is particularly true for the Myosoricinae (Eulipotyphla: Soricidae), a small clade of African shrews that includes both ambulatory forest shrews (Myosorex) and semifossorial mole shrews (Surdisorex). Most species in this subfamily have restricted distributions, and their behavior and ecology are mostly unstudied. To better understand the potential range of locomotory behavior among myosoricines, we used digital x-rays to image and facilitate measuring the forefoot skeletons of 9 species. As a gauge of potential variation, we compared them with the ambulatory talpid Uropsilus (Talpidae) and the semifossorial talpid Neurotrichus. The hand morphologies of myosoricines show a graded range of potential substrate use between ambulatory and semifossorial. Some of these shrews exhibit adaptations for increased burrowing efficiency that are similar to those seen in talpids and other mammals, such as longer, broader distal phalanges and claws and shorter, wider metacarpals and proximal and middle phalanges. They also, however, have characteristics that are distinct from talpids, such as maintenance of forefoot asymmetry and an increased emphasis of ray III.

  3. Leptospira spp. in Rodents and Shrews in Germany

    PubMed Central

    Mayer-Scholl, Anne; Hammerl, Jens Andre; Schmidt, Sabrina; Ulrich, Rainer G.; Pfeffer, Martin; Woll, Dietlinde; Scholz, Holger C.; Thomas, Astrid; Nöckler, Karsten

    2014-01-01

    Leptospirosis is an acute, febrile disease occurring in humans and animals worldwide. Leptospira spp. are usually transmitted through direct or indirect contact with the urine of infected reservoir animals. Among wildlife species, rodents act as the most important reservoir for both human and animal infection. To gain a better understanding of the occurrence and distribution of pathogenic leptospires in rodent and shrew populations in Germany, kidney specimens of 2973 animals from 11 of the 16 federal states were examined by PCR. Rodent species captured included five murine species (family Muridae), six vole species (family Cricetidae) and six shrew species (family Soricidae). The most abundantly trapped animals were representatives of the rodent species Apodemus flavicollis, Clethrionomys glareolus and Microtus agrestis. Leptospiral DNA was amplified in 10% of all animals originating from eight of the 11 federal states. The highest carrier rate was found in Microtus spp. (13%), followed by Apodemus spp. (11%) and Clethrionomys spp. (6%). The most common Leptospira genomospecies determined by duplex PCR was L. kirschneri, followed by L. interrogans and L. borgpetersenii; all identified by single locus sequence typing (SLST). Representatives of the shrew species were also carriers of Leptospira spp. In 20% of Crocidura spp. and 6% of the Sorex spp. leptospiral DNA was detected. Here, only the pathogenic genomospecies L. kirschneri was identified. PMID:25062275

  4. Dietary heavy metal uptake by the least shrew, Cryptotis parva

    SciTech Connect

    Brueske, C.C.; Barrett, G.W. )

    1991-12-01

    Heavy metals from sewage sludge have been reported to concentrate in producers, in primary consumers, and in detritivores. Little research, however, has focused on the uptake of heavy metals from sewage sludge by secondary consumers. The Family Soricidae represents an ideal mammalian taxonomic group to investigate rates of heavy metal transfer between primary and secondary consumers. The least shrew (Cryptotis parva) was used to evaluate the accumulation of heavy metals while maintained on a diet of earthworms collected from long-term sludge-treated old-field communities. This secondary consumer is distributed widely through the eastern United States and its natural diet includes earthworms which makes it a potentially good indicator of heavy metal transfer in areas treated with municipal sludge.

  5. Characterization of Imjin Virus, a Newly Isolated Hantavirus from the Ussuri White-Toothed Shrew (Crocidura lasiura)?

    PubMed Central

    Song, Jin-Won; Kang, Hae Ji; Gu, Se Hun; Moon, Sung Sil; Bennett, Shannon N.; Song, Ki-Joon; Baek, Luck Ju; Kim, Heung-Chul; O'Guinn, Monica L.; Chong, Sung-Tae; Klein, Terry A.; Yanagihara, Richard

    2009-01-01

    Until recently, the single known exception to the rodent-hantavirus association was Thottapalayam virus (TPMV), a long-unclassified virus isolated from the Asian house shrew (Suncus murinus). Robust gene amplification techniques have now uncovered several genetically distinct hantaviruses from shrews in widely separated geographic regions. Here, we report the characterization of a newly identified hantavirus, designated Imjin virus (MJNV), isolated from the lung tissues of Ussuri white-toothed shrews of the species Crocidura lasiura (order Soricomorpha, family Soricidae, subfamily Crocidurinae) captured near the demilitarized zone in the Republic of Korea during 2004 and 2005. Seasonal trapping revealed the highest prevalence of MJNV infection during the autumn, with evidence of infected shrews' clustering in distinct foci. Also, marked male predominance among anti-MJNV immunoglobulin G antibody-positive Ussuri shrews was found, whereas the male-to-female ratio among seronegative Ussuri shrews was near 1. Plaque reduction neutralization tests showed no cross neutralization for MJNV and rodent-borne hantaviruses but one-way cross neutralization for MJNV and TPMV. The nucleotide and deduced amino acid sequences for the different MJNV genomic segments revealed nearly the same calculated distances from hantaviruses harbored by rodents in the subfamilies Murinae, Arvicolinae, Neotominae, and Sigmodontinae. Phylogenetic analyses of full-length S, M, and L segment sequences demonstrated that MJNV shared a common ancestry with TPMV and remained in a distinct out-group, suggesting early evolutionary divergence. Studies are in progress to determine if MJNV is pathogenic for humans. PMID:19357167

  6. Stammerinema hyalinum n. comb. for Filaria hyalina von Linstow, 1890 and its recognition as a senior synonym of Stammerinema rhopalocephalum (So?tys, 1952) (Spirurida: Acuariidae), a parasite of shrews.

    PubMed

    Mutafchiev, Yasen; Mariaux, Jean; Georgiev, Boyko B

    2015-01-01

    Based on a re-examination of type-specimens of Filaria hyalina von Linstow, 1890 from Sorex araneus L. (Mammalia: Soricidae) and morphological studies (light and scanning electron microscopy) of specimens collected from the same host species in Bulgaria and previously identified as Stammerinema rhopalocephalum (So?tys, 1952), both these forms are considered to be conspecific. Accordingly, F. hyalina is transferred to the genus Stammerinema Osche, 1955 as Stammerinema hyalinum n. comb. and the species originally described as Synhimantus rhopalocephalus So?tys, 1952 is considered its junior synonym. PMID:25557751

  7. Designation of the type species of Musaraneus Pomel, 1848 (Mammalia: Soricomorpha: Soricidae)

    USGS Publications Warehouse

    Woodman, N.

    2004-01-01

    The genus name Musaraneus often is attributed to Brisson (1762), however, most of Brisson's names are unavailable. Pomel (1848) subsequently made the name Musaraneus available, but did not designate a type species. The 18 species that Pomel listed under Musaraneus currently are distributed among five modern genera, two of which (Cryptotis Pomel, 1848 and Diplomesodon Brandt, 1852) are predated by Musaraneus. Because Cryptotis and Diplomesodon potentially could be considered junior synonyms of Musaraneus, I propose Sorex leucodon Hermann, 1780 (= Crocidura leucodon) as the type species for Musaraneus, thereby establishing Musaraneus as a junior synonym of Crocidura Wagler, 1832.

  8. A Mitochondrial Phylogeny and Biogeographical Scenario for Asiatic Water Shrews of the Genus Chimarrogale: Implications for Taxonomy and Low-Latitude Migration Routes

    PubMed Central

    Yuan, Shou-Li; Jiang, Xue-Long; Li, Zhen-Ji; He, Kai; Harada, Masashi; Oshida, Tatsuo; Lin, Liang-Kong

    2013-01-01

    The six species and three subspecies in the genus Chimarrogale (Soricomorpha: Soricidae) are commonly referred to as Asiatic water shrews. The Chimarrogale are the most widely distributed group of Nectogaline shrews, extending throughout the Oriental region and Japan. Because of the limited numbers of specimens available for study, the phylogenetic relationships and biogeographical history of this genus have not been comprehensively discussed. We used mitochondrial cytochrome b gene sequences to estimate phylogenetic relationships and divergence times among four Chimarrogale species, including all three subspecies of Chimarrogale himalayica. We also conducted a species delimitation analysis and tested two alternative migration scenarios in Asia through species distribution modeling and a reconstruction of the ancestral distribution. Here, we present the first proposed hypothesis regarding the Asiatic water shrew phylogeny and reveal ten putative species within the four recognized species. Distinct phylogenetic statuses of Chimarrogale phaeura, Chimarrogale platycephala, and Chimarrogale styani were confirmed. Chimarrogale himalayica was strongly supported as paraphyletic. We suggest that three subspecies of Chimarrogale himalayica should be reconsidered as distinct species. However, these suggestions must be considered with caution because only a single locus of a mtDNA gene was used. Four additional putative species, possibly distributed in central southwestern China and Taiwan, are currently undescribed; therefore, comprehensive morphological analyses are warranted to test their taxonomic statuses. The estimated molecular divergence times indicated that rapid speciation occurred during the early Pliocene, and current distribution patterns may have been affected by global cooling during the Pliocene/Pleistocene boundary. Reconstruction of the ancestral distribution and species distribution modeling for Asiatic water shrews revealed a low-latitude migration route over which ancestral Chimarrogale migrated from Europe via Central Asia to their current distribution. Our results demonstrated that Asiatic water shrews could have evolved throughout the low-latitude migration route from Europe to East and Southeast Asia. PMID:24124605

  9. Comparative Morphology of the Papillae Linguales and their Connective Tissue Cores in the Tongue of the Greater Japanese Shrew-mole, Urotrichus talpoides

    PubMed Central

    Yoshimura, K; Shindo, J; Kageyama, I

    2013-01-01

    The external morphology of the papillae linguales (papillae filiformes, papillae fungiformes and papillae vallatae) and their connective tissue cores (CTCs) of the greater Japanese shrew-mole (Urotrichus talpoides) were analysed by optical and scanning electron microscopy. Papillae filiformes were distributed over the dorsal surface of the apex linguae, and on the rostral and caudal regions of the corpus linguae but were less numerous in the mid-region. They were absent from the radix linguae. A pair of oval papillae vallatae was situated at the border between the corpus linguae and the radix linguae. Papillae foliatae were absent. The epithelial surface of each papilla filiformis consisted of a circular concavity, a ring-like wall and either a single thumb-like process or 23 slender pointed processes, depending on their location. The morphology of the CTCs of the papillae filiformes also varied regionally. The papillae linguales of the Japanese shrew-mole were morphologically similar to those of other Talpidae and Soricidae, including the common shrew, particularly with respect to the papillae filiformes in the mid- and caudal regions of the corpus linguae. PMID:22571539

  10. Genomic Characterization of Yogue, Kasokero, Issyk-Kul, Keterah, Gossas, and Thiafora Viruses: Nairoviruses Naturally Infecting Bats, Shrews, and Ticks.

    PubMed

    Walker, Peter J; Widen, Steven G; Firth, Cadhla; Blasdell, Kim R; Wood, Thomas G; Travassos da Rosa, Amelia P A; Guzman, Hilda; Tesh, Robert B; Vasilakis, Nikos

    2015-11-01

    The genus Nairovirus of arthropod-borne bunyaviruses includes the important emerging human pathogen, Crimean-Congo hemorrhagic fever virus (CCHFV), as well as Nairobi sheep disease virus and many other poorly described viruses isolated from mammals, birds, and ticks. Here, we report genome sequence analysis of six nairoviruses: Thiafora virus (TFAV) that was isolated from a shrew in Senegal; Yogue (YOGV), Kasokero (KKOV), and Gossas (GOSV) viruses isolated from bats in Senegal and Uganda; Issyk-Kul virus (IKV) isolated from bats in Kyrgyzstan; and Keterah virus (KTRV) isolated from ticks infesting a bat in Malaysia. The S, M, and L genome segments of each virus were found to encode proteins corresponding to the nucleoprotein, polyglycoprotein, and polymerase protein of CCHFV. However, as observed in Leopards Hill virus (LPHV) and Erve virus (ERVV), polyglycoproteins encoded in the M segment lack sequences encoding the double-membrane-spanning CCHFV NSm protein. Amino acid sequence identities, complement-fixation tests, and phylogenetic analysis indicated that these viruses cluster into three groups comprising KKOV, YOGV, and LPHV from bats of the suborder Yingochiroptera; KTRV, IKV, and GOSV from bats of the suborder Yangochiroptera; and TFAV and ERVV from shrews (Soricomorpha: Soricidae). This reflects clade-specific host and vector associations that extend across the genus. PMID:26324724

  11. The Taming of the Shrew

    NASA Astrophysics Data System (ADS)

    Gad-El-Hak, M.

    1996-11-01

    Considering the extreme complexity of the turbulence problem in general and the unattainability of first-principles analytical solutions in particular, it is not surprising that controlling a turbulent flow remains a challenging task, mired in empiricism and unfulfilled promises and aspirations. Brute force suppression, or taming, of turbulence via active control strategies is always possible, but the penalty for doing so often exceeds any potential savings. The artifice is to achieve a desired effect with minimum energy expenditure. Spurred by the recent developments in chaos control, microfabrication and neural networks, efficient reactive control of turbulent flows, where the control input is optimally adjusted based on feedforward or feedback measurements, is now in the realm of the possible for future practical devices. But regardless of how the problem is approached, combating turbulence is always as arduous as the taming of the shrew. The former task will be emphasized during the oral presentation, but for this abstract we reflect on a short verse from the latter. From William Shakespeare's The Taming of the Shrew. Curtis (Petruchio's servant, in charge of his country house): Is she so hot a shrew as she's reported? Grumio (Petruchio's personal lackey): She was, good Curtis, before this frost. But thou know'st winter tames man, woman, and beast; for it hath tamed my old master, and my new mistress, and myself, fellow Curtis.

  12. The neurobiology of Etruscan shrew active touch

    PubMed Central

    Brecht, Michael; Naumann, Robert; Anjum, Farzana; Wolfe, Jason; Munz, Martin; Mende, Carolin; Roth-Alpermann, Claudia

    2011-01-01

    The Etruscan shrew, Suncus etruscus, is not only the smallest terrestrial mammal, but also one of the fastest and most tactile hunters described to date. The shrew's skeletal muscle consists entirely of fast-twitch types and lacks slow fibres. Etruscan shrews detect, overwhelm, and kill insect prey in large numbers in darkness. The cricket prey is exquisitely mechanosensitive and fast-moving, and is as big as the shrew itself. Experiments with prey replica show that shape cues are both necessary and sufficient for evoking attacks. Shrew attacks are whisker guided by motion- and size-invariant Gestalt-like prey representations. Shrews often attack their prey prior to any signs of evasive manoeuvres. Shrews whisk at frequencies of approximately 14 Hz and can react with latencies as short as 2530 ms to prey movement. The speed of attacks suggests that shrews identify and classify prey with a single touch. Large parts of the shrew's brain respond to vibrissal touch, which is represented in at least four cortical areas comprising collectively about a third of the cortical volume. Etruscan shrews can enter a torpid state and reduce their body temperature; we observed that cortical response latencies become two to three times longer when body temperature drops from 36C to 24C, suggesting that endothermy contributes to the animal's high-speed sensorimotor performance. We argue that small size, high-speed behaviour and extreme dependence on touch are not coincidental, but reflect an evolutionary strategy, in which the metabolic costs of small body size are outweighed by the advantages of being a short-range high-speed touch and kill predator. PMID:21969684

  13. The neurobiology of Etruscan shrew active touch.

    PubMed

    Brecht, Michael; Naumann, Robert; Anjum, Farzana; Wolfe, Jason; Munz, Martin; Mende, Carolin; Roth-Alpermann, Claudia

    2011-11-12

    The Etruscan shrew, Suncus etruscus, is not only the smallest terrestrial mammal, but also one of the fastest and most tactile hunters described to date. The shrew's skeletal muscle consists entirely of fast-twitch types and lacks slow fibres. Etruscan shrews detect, overwhelm, and kill insect prey in large numbers in darkness. The cricket prey is exquisitely mechanosensitive and fast-moving, and is as big as the shrew itself. Experiments with prey replica show that shape cues are both necessary and sufficient for evoking attacks. Shrew attacks are whisker guided by motion- and size-invariant Gestalt-like prey representations. Shrews often attack their prey prior to any signs of evasive manoeuvres. Shrews whisk at frequencies of approximately 14 Hz and can react with latencies as short as 25-30 ms to prey movement. The speed of attacks suggests that shrews identify and classify prey with a single touch. Large parts of the shrew's brain respond to vibrissal touch, which is represented in at least four cortical areas comprising collectively about a third of the cortical volume. Etruscan shrews can enter a torpid state and reduce their body temperature; we observed that cortical response latencies become two to three times longer when body temperature drops from 36C to 24C, suggesting that endothermy contributes to the animal's high-speed sensorimotor performance. We argue that small size, high-speed behaviour and extreme dependence on touch are not coincidental, but reflect an evolutionary strategy, in which the metabolic costs of small body size are outweighed by the advantages of being a short-range high-speed touch and kill predator. PMID:21969684

  14. Phylogeography of the Northern short-tailed shrew, Blarina brevicauda (Insectivora: Soricidae): past fragmentation and postglacial recolonization.

    PubMed

    Brant, Sara V; Ort, Guillermo

    2003-06-01

    Blarina brevicauda is distributed across the northeastern region of North America, in areas previously covered by Pleistocene glaciers. Previous molecular systematic study of the species in the genus Blarina suggested the presence of two distinct eastern and western phylogroups within B. brevicauda, in agreement with traditionally recognized semi-species. To expand the previous work, a collection of 76 individuals from 14 localities collected throughout the range of B. brevicauda was used to assess the mitochondrial (mt) cytochrome b genealogy for this species. Minimum evolution, maximum parsimony, analysis of molecular variance and nested clade analysis each supported the same conclusions of two well-differentiated and monophyletic east-west groups, separated by the Mississippi River. Denser sampling in areas immediately East of the Mississippi basin revealed further subdivision within the eastern phylogroup into an East-Central and an Appalachian clade. The western phylogroup differed from the eastern phylogroup by 2.5% mean absolute DNA sequence difference. About 65% of the genetic variance among samples was explained by the east-west subdivision alone. High haplotype diversities, low nucleotide diversities and unimodal mismatch distributions within subclades suggest recent expansion or diversification within each group. No phylogeographic structure was found within the western phylogroup, but genetic structure because of restricted gene flow and isolation by distance was inferred for the eastern group. The present distribution of B. brevicauda is best explained by past fragmentation and range expansion events during and following the Pleistocene glacial cycles. PMID:12755873

  15. Active Touch During Shrew Prey Capture

    PubMed Central

    Munz, Martin; Brecht, Michael; Wolfe, Jason

    2010-01-01

    Although somatosensation in multiple whisker systems has been studied in considerable detail, relatively little information is available regarding whisker usage and movement patterns during natural behaviors. The Etruscan shrew, one of the smallest mammals, relies heavily on its whisker system to detect and kill its highly mobile insect prey. Here, we tracked whisker and body motion during prey capture. We found that shrews made periodic whisker movements (whisking) with frequencies ranging from 12 to 17?Hz. We compared shrew and rat whisking and found that shrew whisking was smaller amplitude and higher frequency than rat whisking, but that the shrew and rat whisking cycle were similar in that the velocity was higher during retraction than protraction. We were able to identify four phases during the shrew hunting behavior: (i) an immobile phase often preceding hunting, (ii) a search phase upon the initiation of hunting, (iii) a contact phase defined by whisker-to-cricket contact, and (iv) an attack phase, characterized by a rapid head movement directed toward the cricket. During the searching phase, whisking was generally rhythmic and whiskers were protracted forward. After prey contact, whisking amplitude decreased and became more variable. The final strike was associated with an abrupt head movement toward the prey with high head acceleration. Prey capture proceeded extremely fast and we obtained evidence that shrews can initiate corrective maneuvers with a minimal latency <30?ms. While the shrew's rostrum is straight and elongated during most behaviors, we show for the first time that shrews bend their rostrum during the final strike and grip their prey with a parrot beak shaped snout. PMID:21283557

  16. Cryptococcosis in tree shrews (Tupaia tana and Tupaia minor) and elephant shrews (Macroscelides proboscides).

    PubMed

    Tell, L A; Nichols, D K; Fleming, W P; Bush, M

    1997-06-01

    Fungal infections due to Cryptococcus neoformans occurred in seven short-eared elephant shrews (Macroscelides proboscides), six large tree shrews (Tupaia tana), and five lesser tree shrews (Tupaia minor) at the National Zoological Park during a 30-mo period in 1991-1993. Clinical signs were absent or included weight loss, shivering, dyspnea, and/or neurologic disease. Definitive antemortem diagnostic techniques included tracheal lavage and serum cryptococcal antigen latex agglutination titers. Thirteen cases were diagnosed solely by postmortem examination. The source of infection for these animals was uncertain, but C. neoformans is commonly found in soil and other organic material. Two lesser tree shrews and one large tree shrew received antifungal therapy and converted to a negative serum cryptococcal antigen titer. PMID:9279407

  17. Newfound Hantavirus in Chinese Mole Shrew, Vietnam

    PubMed Central

    Song, Jin-Won; Kang, Hae Ji; Song, Ki-Joon; Truong, Thang T.; Bennett, Shannon N.; Arai, Satoru; Truong, Ninh U.

    2007-01-01

    Sequence analysis of the full-length medium segment and the partial small and large segments of a hantavirus, detected by reverse transcriptionPCR in lung tissues of the Chinese mole shrew (Anourosorex squamipes) captured in Cao Bang Province, Vietnam, in December 2006, indicated that it is genetically distinct from rodentborne hantaviruses. PMID:18217572

  18. Recombinogenic telomeres in diploid Sorex granarius (Soricidae, Eulipotyphla) fibroblast cells.

    PubMed

    Zhdanova, N S; Draskovic, I; Minina, J M; Karamysheva, T V; Novo, C L; Liu, W-Y; Porreca, R M; Gibaud, A; Zvereva, M E; Skvortsov, D A; Rubtsov, N B; Londoo-Vallejo, A

    2014-08-01

    The telomere structure in the Iberian shrew Sorex granarius is characterized by unique, striking features, with short arms of acrocentric chromosomes carrying extremely long telomeres (up to 300 kb) with interspersed ribosomal DNA (rDNA) repeat blocks. In this work, we investigated the telomere physiology of S. granarius fibroblast cells and found that telomere repeats are transcribed on both strands and that there is no telomere-dependent senescence mechanism. Although telomerase activity is detectable throughout cell culture and appears to act on both short and long telomeres, we also discovered that signatures of a recombinogenic activity are omnipresent, including telomere-sister chromatid exchanges, formation of alternative lengthening of telomeres (ALT)-associated PML-like bodies, production of telomere circles, and a high frequency of telomeres carrying marks of a DNA damage response. Our results suggest that recombination participates in the maintenance of the very long telomeres in normal S. granarius fibroblasts. We discuss the possible interplay between the interspersed telomere and rDNA repeats in the stabilization of the very long telomeres in this organism. PMID:24842907

  19. Distinct Lineages of Bufavirus in Wild Shrews and Nonhuman Primates.

    PubMed

    Sasaki, Michihito; Orba, Yasuko; Anindita, Paulina D; Ishii, Akihiro; Ueno, Keisuke; Hang'ombe, Bernard M; Mweene, Aaron S; Ito, Kimihito; Sawa, Hirofumi

    2015-07-01

    Viral metagenomic analysis identified a new parvovirus genome in the intestinal contents of wild shrews in Zambia. Related viruses were detected in spleen tissues from wild shrews and nonhuman primates. Phylogenetic analyses showed that these viruses are related to human bufaviruses, highlighting the presence and genetic diversity of bufaviruses in wildlife. PMID:26079728

  20. Tactile experience shapes prey-capture behavior in Etruscan shrews

    PubMed Central

    Anjum, Farzana; Brecht, Michael

    2012-01-01

    A crucial role of tactile experience for the maturation of neural response properties in the somatosensory system is well established, but little is known about the role of tactile experience in the development of tactile behaviors. Here we study how tactile experience affects prey capture behavior in Etruscan shrews, Suncus etruscus. Prey capture in adult shrews is a high-speed behavior that relies on precise attacks guided by tactile Gestalt cues. We studied the role of tactile experience by three different approaches. First, we analyzed the hunting skills of young shrews' right after weaning. We found that prey capture in young animals in most, but not all, aspects is similar to that of adults. Second, we performed whisker trimming for 34 weeks after birth. Such deprivation resulted in a lasting disruption of prey capture even after whisker re-growth: attacks lacked precise targeting and had a lower success rate. Third, we presented adult shrews with an entirely novel prey species, the giant cockroach. The shape of this roach is very different from the shrew's normal (cricket) prey and the thoraxthe preferred point of attack in cricketsis protected by a heavy cuticle. Initially shrews attacked giant roaches the same way they attack crickets and targeted the thoracic region. With progressive experience, however, shrews adopted a new attack strategy targeting legs and underside of the roaches while avoiding other body parts. Speed and efficiency of attacks improved. These data suggest that tactile experience shapes prey capture behavior. PMID:22701408

  1. Tactile guidance of prey capture in Etruscan shrews.

    PubMed

    Anjum, Farzana; Turni, Hendrik; Mulder, Paul G H; van der Burg, Johannes; Brecht, Michael

    2006-10-31

    Whereas visuomotor behaviors and visual object recognition have been studied in detail, we know relatively little about tactile object representations. We investigate a new model system for the tactile guidance of behavior, namely prey (cricket) capture by one of the smallest mammals, the Etruscan shrew, Suncus etruscus. Because of their high metabolic rate and nocturnal lifestyle, Etruscan shrews are forced to detect, overwhelm, and kill prey in large numbers in darkness. Crickets are exquisitely mechanosensitive, fast-moving prey, almost as big as the shrew itself. Shrews succeed in hunting by lateralized, precise, and fast attacks. Removal experiments demonstrate that both macrovibrissae and microvibrissae are required for prey capture, with the macrovibrissae being involved in attack targeting. Experiments with artificial prey replica show that tactile shape cues are both necessary and sufficient for evoking attacks. Prey representations are motion- and size-invariant. Shrews distinguish and memorize prey features. Corrective maneuvers and cricket shape manipulation experiments indicate that shrew behavior is guided by Gestalt-like prey descriptions. Thus, tactile object recognition in Etruscan shrews shares characteristics of human visual object recognition, but it proceeds faster and occurs in a 20,000-times-smaller brain. PMID:17060642

  2. Tactile guidance of prey capture in Etruscan shrews

    PubMed Central

    Anjum, Farzana; Turni, Hendrik; Mulder, Paul G. H.; van der Burg, Johannes; Brecht, Michael

    2006-01-01

    Whereas visuomotor behaviors and visual object recognition have been studied in detail, we know relatively little about tactile object representations. We investigate a new model system for the tactile guidance of behavior, namely prey (cricket) capture by one of the smallest mammals, the Etruscan shrew, Suncus etruscus. Because of their high metabolic rate and nocturnal lifestyle, Etruscan shrews are forced to detect, overwhelm, and kill prey in large numbers in darkness. Crickets are exquisitely mechanosensitive, fast-moving prey, almost as big as the shrew itself. Shrews succeed in hunting by lateralized, precise, and fast attacks. Removal experiments demonstrate that both macrovibrissae and microvibrissae are required for prey capture, with the macrovibrissae being involved in attack targeting. Experiments with artificial prey replica show that tactile shape cues are both necessary and sufficient for evoking attacks. Prey representations are motion- and size-invariant. Shrews distinguish and memorize prey features. Corrective maneuvers and cricket shape manipulation experiments indicate that shrew behavior is guided by Gestalt-like prey descriptions. Thus, tactile object recognition in Etruscan shrews shares characteristics of human visual object recognition, but it proceeds faster and occurs in a 20,000-times-smaller brain. PMID:17060642

  3. Tactile experience shapes prey-capture behavior in Etruscan shrews.

    PubMed

    Anjum, Farzana; Brecht, Michael

    2012-01-01

    A crucial role of tactile experience for the maturation of neural response properties in the somatosensory system is well established, but little is known about the role of tactile experience in the development of tactile behaviors. Here we study how tactile experience affects prey capture behavior in Etruscan shrews, Suncus etruscus. Prey capture in adult shrews is a high-speed behavior that relies on precise attacks guided by tactile Gestalt cues. We studied the role of tactile experience by three different approaches. First, we analyzed the hunting skills of young shrews' right after weaning. We found that prey capture in young animals in most, but not all, aspects is similar to that of adults. Second, we performed whisker trimming for 3-4 weeks after birth. Such deprivation resulted in a lasting disruption of prey capture even after whisker re-growth: attacks lacked precise targeting and had a lower success rate. Third, we presented adult shrews with an entirely novel prey species, the giant cockroach. The shape of this roach is very different from the shrew's normal (cricket) prey and the thorax-the preferred point of attack in crickets-is protected by a heavy cuticle. Initially shrews attacked giant roaches the same way they attack crickets and targeted the thoracic region. With progressive experience, however, shrews adopted a new attack strategy targeting legs and underside of the roaches while avoiding other body parts. Speed and efficiency of attacks improved. These data suggest that tactile experience shapes prey capture behavior. PMID:22701408

  4. Barrelettes without Barrels in the American Water Shrew

    PubMed Central

    Catania, Kenneth C.; Catania, Elizabeth H.; Sawyer, Eva K.; Leitch, Duncan B.

    2013-01-01

    Water shrews (Sorex palustris) depend heavily on their elaborate whiskers to navigate their environment and locate prey. They have small eyes and ears with correspondingly small optic and auditory nerves. Previous investigations have shown that water shrew neocortex is dominated by large representations of the whiskers in primary and secondary somatosensory cortex (S1 and S2). Flattened sections of juvenile cortex processed for cytochrome oxidase revealed clear borders of the whisker pad representation in S1, but no cortical barrels. We were therefore surprised to discover prominent barrelettes in brainstem of juvenile water shrews in the present investigation. These distinctive modules were found in the principal trigeminal nucleus (PrV), and in two of the three spinal trigeminal subnuclei (interpolaris SpVi and caudalis SpVc). Analysis of the shrew's whisker pad revealed the likely relationship between whiskers and barrelettes. Barrelettes persisted in adult water shrew PrV, but barrels were also absent from adult cortex. Thus in contrast to mice and rats, which have obvious barrels in primary somatosensory cortex and less clear barrelettes in the principal nucleus, water shrews have clear barrelettes in the brainstem and no barrels in the neocortex. These results highlight the diverse ways that similar mechanoreceptors can be represented in the central nervous systems of different species. PMID:23755296

  5. Adoption of a nestling house mouse by a female short-tailed shrew

    USGS Publications Warehouse

    Blus, L.J.; Johnson, D.A.

    1969-01-01

    A nursing female short-tailed shrew adopted a nestling house mouse. The mouse was observed in the nest with the female and her litter of shrews three days after it was introduced into the aluminum box containing the shrews, but it was found dead in the nest four days later.

  6. Effects of late quaternary climate change on Palearctic shrews.

    PubMed

    Prost, Stefan; Klietmann, Johannes; van Kolfschoten, Thijs; Guralnick, Robert P; Waltari, Eric; Vrieling, Klaas; Stiller, Mathias; Nagel, Doris; Rabeder, Gernot; Hofreiter, Michael; Sommer, Robert S

    2013-06-01

    The Late Quaternary was a time of rapid climatic oscillations and drastic environmental changes. In general, species can respond to such changes by behavioral accommodation, distributional shifts, ecophenotypic modifications (nongenetic), evolution (genetic) or ultimately face local extinction. How those responses manifested in the past is essential for properly predicting future ones especially as the current warm phase is further intensified by rising levels of atmospheric carbon dioxide. Here, we use ancient DNA (aDNA) and morphological features in combination with ecological niche modeling (ENM) to investigate genetic and nongenetic responses of Central European Palearctic shrews to past climatic change. We show that a giant form of shrew, previously described as an extinct Pleistocene Sorex species, represents a large ecomorph of the common shrew (Sorex araneus), which was replaced by populations from a different gene-pool and with different morphology after the Pleistocene Holocene transition. We also report the presence of the cold-adapted tundra shrew (S.tundrensis) in Central Europe. This species is currently restricted to Siberia and was hitherto unknown as an element of the Pleistocene fauna of Europe. Finally, we show that there is no clear correlation between climatic oscillations within the last 50000years and body size in shrews and conclude that a special nonanalogous situation with regard to biodiversity and food supply in the Late Glacial may have caused the observed large body size. PMID:23505017

  7. The formation and extinction of fear memory in tree shrews

    PubMed Central

    Shang, Shujiang; Wang, Cong; Guo, Chengbing; Huang, Xu; Wang, Liecheng; Zhang, Chen

    2015-01-01

    Fear is an emotion that is well-studied due to its importance for animal survival. Experimental animals, such as rats and mice, have been widely used to model fear. However, higher animals such as nonhuman primates have rarely been used to study fear due to ethical issues and high costs. Tree shrews are small mammals that are closely related to primates; they have been used to model human-related psychosocial conditions such as stress and alcohol tolerance. Here, we describe an experimental paradigm to study the formation and extinction of fear memory in tree shrews. We designed an experimental apparatus of a light/dark box with a voltage foot shock. We found that tree shrews preferred staying in the dark box in the daytime without stimulation and showed avoidance to voltage shocks applied to the footplate in a voltage-dependent manner. Foot shocks applied to the dark box for 5 days (10 min per day) effectively reversed the light–dark preference of the tree shrews, and this memory lasted for more than 50 days without any sign of memory decay (extinction) in the absence of further stimulation. However, this fear memory was reversed with 4 days of reverse training by applying the same stimulus to the light box. When reducing the stimulus intensity during the training period, a memory extinction and subsequently reinstatement effects were observed. Thus, our results describe an efficient method of monitoring fear memory formation and extinction in tree shrews. PMID:26283941

  8. Cytoarchitecture, areas, and neuron numbers of the Etruscan shrew cortex.

    PubMed

    Naumann, R K; Anjum, F; Roth-Alpermann, C; Brecht, M

    2012-08-01

    The Etruscan shrew, Suncus etruscus, is one of the smallest mammals. Etruscan shrews can recognize prey shape with amazing speed and accuracy, based on whisker-mediated tactile cues. Because of its small size, quantitative analysis of the Etruscan shrew cortex is more tractable than in other animals. To quantitatively assess the anatomy of the Etruscan shrew's brain, we sectioned brains and applied Nissl staining and NeuN (neuronal nuclei) antibody staining. On the basis of these stains, we estimated the number of neurons of 10 cortical hemispheres by using Stereoinvestigator and Neurolucida (MBF Bioscience) software. On average, the neuron number per hemisphere was found to be ~1 million. We also measured cortical surface area and found an average of 11.1 mm (n = 7) and an average volume of 5.3 mm (n = 10) per hemisphere. We identified 13 cortical regions by cytoarchitectonic boundaries in coronal, sagittal, and tangential sections processed for Nissl substance, myelin, cytochrome oxidase, ionic zinc, neurofilaments, and vesicular glutamate transporter 2 (VGluT2). The Etruscan shrew is a highly tactile animal with a large somatosensory cortex, which contains a barrel field, but the barrels are much less clearly defined than in rodents. The anatomically derived cortical partitioning scheme roughly corresponds to physiologically derived maps of neocortical sensory areas. PMID:22252518

  9. Cortical organization in the Etruscan shrew (Suncus etruscus).

    PubMed

    Roth-Alpermann, Claudia; Anjum, Farzana; Naumann, Robert; Brecht, Michael

    2010-11-01

    Cortical organization in the Etruscan shrew is of comparative interest because of its small size and because the Etruscan shrew is an amazing tactile hunter. Here we investigated cortical organization in Etruscan shrews by electrophysiological mapping. We developed an anesthesia protocol for this very small mammal in which we combined massive application of local anesthesia, very slow induction of general anesthesia, and passive cooling. Under this anesthesia regime, we characterized auditory, visual, and somatosensory cortical responses. We found that large parts of shrew cortex respond to such stimuli. Of the responsive sites, a small fraction (?14%) responded to visual stimuli in a caudally located region. Another small fraction of sites (?11%) responded to auditory stimuli in a centrally located region. The majority of sites (?75%) responded to tactile stimuli. We identified two topographically organized somatosensory areas with small receptive fields referred to as putative primary somatosensory cortex and putative secondary somatosensory cortex. In a posterior-lateral region that partially overlaps with piriform cortex, we observed large somatosensory receptive fields and often polysensory responses. In an anterior-lateral region that partially overlaps with piriform cortex, we observed large unimodal somatosensory receptive fields. Our findings demonstrate a remarkable degree of tactile specialization in Etruscan shrew cortex. PMID:20668271

  10. Boginia virus, a newfound hantavirus harbored by the Eurasian water shrew (Neomys fodiens) in Poland

    PubMed Central

    2013-01-01

    Background Guided by decades-old reports of hantaviral antigens in the Eurasian common shrew (Sorex araneus) and the Eurasian water shrew (Neomys fodiens) in European Russia, we employed RT-PCR to analyze lung tissues of soricine shrews, captured in Boginia, Huta D?utowska and Kurowice in central Poland during September 2010, 2011 and 2012. Findings In addition to Seewis virus (SWSV), which had been previously found in Eurasian common shrews elsewhere in Europe, a genetically distinct hantavirus, designated Boginia virus (BOGV), was detected in Eurasian water shrews captured in each of the three villages. Phylogenetic analysis, using maximum likelihood and Bayesian methods, showed that BOGV formed a separate lineage distantly related to SWSV. Conclusions Although the pathogenic potential of BOGV and other recently identified shrew-borne hantaviruses is still unknown, clinicians should be vigilant for unusual febrile diseases and clinical syndromes occurring among individuals reporting exposures to shrews. PMID:23693084

  11. Bioenergetics and thermal physiology of American water shrews (Sorex palustris).

    PubMed

    Gusztak, R W; Macarthur, R A; Campbell, K L

    2005-02-01

    Rates of O(2) consumption and CO(2) production, telemetered body temperature (T(b)) and activity level were recorded from adult and subadult water shrews (Sorex palustris) over an air temperature (T(a)) range of 3-32 degrees C. Digesta passage rate trials were conducted before metabolic testing to estimate the minimum fasting time required for water shrews to achieve a postabsorptive state. Of the 228 metabolic trials conducted on 15 water shrews, 146 (64%) were discarded because the criteria for inactivity were not met. Abdominal T(b) of S. palustris was independent of T(a) and averaged 38.64 +/- 0.07 degrees C. The thermoneutral zone extended from 21.2 degrees C to at least 32 degrees C. Our estimate of the basal metabolic rate for resting, postabsorptive water shrews (96.88 +/- 2.93 J g(-1) h(-1) or 4.84 +/- 0.14 ml O(2) g(-1) h(-1)) was three times the mass-predicted value, while their minimum thermal conductance in air (0.282 +/- 0.013 ml O(2) g(-1) h(-1)) concurred with allometric predictions. The mean digesta throughput time of water shrews fed mealworms (Tenebrio molitor) or ground meat was 50-55 min. The digestibility coefficients for metabolizable energy (ME) of water shrews fed stickleback minnows (Culaea inconstans) and dragonfly nymphs (Anax spp. and Libellula spp.) were 85.4 +/- 1.3% and 82.8 +/- 1.1%, respectively. The average metabolic rate (AMR) calculated from the gas exchange of six water shrews at 19-22 degrees C (208.0 +/- 17.0 J g(-1) h(-1)) was nearly identical to the estimate of energy intake (202.9 +/- 12.9 J g(-1) h(-1)) measured for these same animals during digestibility trials (20 degrees C). Based on 24-h activity trials and our derived ME coefficients, the minimum daily energy requirement of an adult (14.4 g) water shrew at T(a) = 20 degrees C is 54.0 kJ, or the energetic equivalent of 14.7 stickleback minnows. PMID:15592850

  12. Microparasite assemblages of conspecific shrew populations in Southern California

    USGS Publications Warehouse

    Laakkonen, J.; Fisher, R.N.; Case, T.J.

    2003-01-01

    The microparasite component communities of 2 species of shrews, Notiosorex crawfordi and Sorex ornatus, were investigated for the first time in 2 isolated and 3 continuous landscapes in southern California. With microscopical examination, a total of 6 parasite species was found in N. crawfordi and 8 species in S. ornatus. The highest number (5) of parasite species was detected in the lungs. The corrected estimate of parasite species richness did not significantly correlate with the host abundance in either shrew species. Altitude, and also latitude in N. crawfordi, appeared to be significantly positively associated with the parasite species richness, but this could be due to a false association because of the rare occurrence of some of the parasites or the small altitude range (or both). No other landscape variable analyzed (location, size of the study site, disturbance) was significantly associated with the parasite species richness of the shrews. The parasite assemblages of the 2 shrew species were similar despite the fact that N. crawfordi has a lower metabolic rate than S. ornatus.

  13. Cortical organization in shrews: evidence from five species.

    PubMed

    Catania, K C; Lyon, D C; Mock, O B; Kaas, J H

    1999-07-19

    Cortical organization was examined in five shrew species. In three species, Blarina brevicauda, Cryptotis parva, and Sorex palustris, microelectrode recordings were made in cortex to determine the organization of sensory areas. Cortical recordings were then related to flattened sections of cortex processed for cytochrome oxidase or myelin to reveal architectural borders. An additional two species (Sorex cinereus and Sorex longirostris) with visible cortical subdivisions based on histology alone were analyzed without electrophysiological mapping. A single basic plan of cortical organization was found in shrews, consisting of a few clearly defined sensory areas located caudally in cortex. Two somatosensory areas contained complete representations of the contralateral body, corresponding to primary somatosensory cortex (S1) and secondary somatosensory cortex (S2). A small primary visual cortex (V1) was located closely adjacent to S1, whereas auditory cortex (A1) was located in extreme caudolateral cortex, partially encircled by S2. Areas did not overlap and had sharp, histochemically apparent and electrophysiologically defined borders. The adjacency of these areas suggests a complete absence of intervening higher level or association areas. Based on a previous study of corticospinal connections, a presumptive primary motor cortex (M1) was identified directly rostral to S1. Apparently, in shrews, the solution to having extremely little neocortex is to have only a few small cortical subdivisions. However, the small areas remain discrete, well organized, and functional. This cortical organization in shrews is likely a derived condition, because a wide range of extant mammals have a greater number of cortical subdivisions. PMID:10397395

  14. Short-tailed shrews as reservoirs of the agents of Lyme disease and human babesiosis.

    PubMed

    Telford, S R; Mather, T N; Adler, G H; Spielman, A

    1990-10-01

    To determine whether short-tailed shrews (Blarina brevicauda) serve as reservoir hosts for the Lyme disease spirochete (Borrelia burgdorferi) and the agent of human babesiosis (Babesia microti), we examined nymphal ticks that had fed as larvae on shrews collected from 3 enzootic sites in coastal Massachusetts for evidence of infection by either or both of these agents. Xenodiagnosis indicated that 11 of 14 shrews were infected by B. burgdorferi. One of 3 piroplasm-infected shrews also infected ticks with B. microti. In a site where the piroplasm is endemic, 11 of 17 shrews showed patent parasitemias by thin blood smears. Of these, 4 had parasitemias exceeding 40%. Few immature ticks infested shrews, however, suggesting that B. brevicauda, although abundant in some endemic sites and serving as a competent reservoir, would contribute minimally to the population of infected nymphs. PMID:2213411

  15. Short-tailed shrews: Toxicity and residue relationships of DDT, dieldrin, and endrin

    USGS Publications Warehouse

    Blus, L.J.

    1978-01-01

    Experiments involving dietary toxicity and residue relationships of DDT, dieldrin, and endrin were conducted with short-tailed shrews. Dietary concentrations of DDT dissolved in vegetable oils were usually more toxic than diets containing comparable amounts of powdered DDT. Younger shrews, particularly females, were more tolerant of powdered DDT than older animals; yet, there were no conspicuous age differences in toxicity of DDT dissolved in oils. In comparison to other mammals, short-tailed shrews are not unusually sensitive to DDT, dieldrin, or endrin on the basis of two-week feeding tests. The influence of age and sex on toxicity of DDT, endrin, and dieldrin was sometimes more important than body weight. Of those shrews of the same age and sex that were fed the same dietary dosage, heavier shrews were more tolerant than lighter individuals; and, heavier shrews tended to lose a greater percentage of body weight before death. There was a range of 15 to 105 DDT equivalents in brains of shrews dying on dietary dosages of DDT. Six shrews fed a high level of DDT seemed to have unusual metabolite capabilities and died with apparent lethal levels of DDD in their brains. Levels of dieldrin in brains of shrews that died on a dietary dosage of dieldrin ranged from 3.7 to 12.6 ppm. In the rates of gain and loss experiments where shrews were given diets containing 400 ppm DDT or 50 ppm dieldrin up to 17 days, high residues were noted in tissues of shrews after two weeks on a contaminated diet and a few died at that time. After shrews were placed on clean food, it was determined that >50% of the dieldrin residues in carcass and brain were lost in 50% of residues of DDT and metabolites in brains after 2 weeks on clean food; males lost nearly 50% of residues in carcasses after two weeks on clean food compared with a loss of only 11% in females.

  16. The occurrence of Centrorhynchus (Acanthocephala) in shrews (Sorex araneus and Sorex minutus) in the United Kingdom.

    PubMed

    Ewald, J A; Crompton, D W; Johnson, I; Stoddart, R C

    1991-06-01

    Encysted acanthocephalans belonging to the genus Centrorhynchus were found in the body cavities of Sorex araneus (common shrew) and Sorex minutus (pygmy shrew) from Boxworth, Cambridgeshire, U.K. Fifty percent of the male S. araneus and 67% of the male S. minutus examined were found to be infected, with the mean intensity (+/-SD) being 54.3 +/- 91.3 and 14.7 +/- 18.4, respectively. The species of Centrorhynchus in the shrews may be Centrorhynchus aluconis, which is distributed widely in tawny owls, Strix aluco, in the United Kingdom. Shrews appear to serve as paratenic hosts for C. aluconis. PMID:2040960

  17. Why do shrews twitter? Communication or simple echo-based orientation

    PubMed Central

    Siemers, Bjrn M.; Schauermann, Grit; Turni, Hendrik; von Merten, Sophie

    2009-01-01

    Shrews are very vocal animals. We tested behaviourally whether the high-pitched laryngeal twittering calls of as-yet unclear function serve for communication or echo-based orientation. We used a representative species from each of the two largest phylogenetic groups of shrews. In both species, experimental manipulation of substrate density, but not of the likelihood of conspecific presence, affected the shrews' call rate when exploring an unknown environment. This adaptation of call rate to the degree of habitat clutter parallels bat echolocation and suggests that shrews may use the echoes and reverberations of their calls for identifying routes through their habitat or for probing habitat type. To assess the acoustic feasibility of shrew echo orientation, we ensonified shrew habitats in the field with an artificial shrew (small speaker mounted close to a sensitive microphone). The data showed that shrew-like calls can indeed yield echo scenes useful for habitat assessment at close range, but beyond the range of the shrews' vibrissae. PMID:19535367

  18. The least shrew (Cryptotis parva) as a laboratory animal.

    PubMed

    Mock, O B

    1982-04-01

    Wild least shrews, Cryptotis parva, have been maintained in the laboratory for 15 years. Animals were confined in small, open terraria with loam soil covering the floor. The shrews were fed mealworms and a mixture of ground meat and mink diet twice daily. Heterosexual pairing was the mating system most commonly employed. The gestation period was 21 to 22 days, and the mean litter size was 4.3 with a range of 1-9 offspring. The young were weaned at 18-20 days of age and were sexually mature prior to the age of 40 days. Periodontal disease was the only disease which threatened the colony, and it was controlled by adding oxytetracycline hydrochloride to the water. Maximum laboratory survival time was 889 days. PMID:7078086

  19. The humerus of Cryptotis colombiana and its bearing on the species? phylogenetic relationships (Soricomorpha: Soricidae)

    USGS Publications Warehouse

    Woodman, N.; Cuartas-Calle, C.A.; Delgado-V., C.A.

    2003-01-01

    The Colombian small-eared shrew, Cryptotis colombiana Woodman and Timm, was described from the Colombian Andes in 1993. Its original allocation to the Cryptotis nigrescens-group recently was questioned based on several cranial characters the species appeared to share with some members of the Cryptotis thomasi-group. We review characteristics of the C. nigrescens- and C. thomasi-groups, and we describe the humerus of C. colombiana and the humerus and manus of Cryptotis medellinia. The morphology of the humerus joins the suite of characters that supports the hypotheses that C. colombiana is not a member of the C. thomasi-group and that all remaining South American species form a cohesive, definable set that is probably monophyletic.

  20. Neurochemical Characterization of the Tree Shrew Dorsal Striatum

    PubMed Central

    Rice, Matthew W.; Roberts, Rosalinda C.; Melendez-Ferro, Miguel; Perez-Costas, Emma

    2011-01-01

    The striatum is a major component of the basal ganglia and is associated with motor and cognitive functions. Striatal pathologies have been linked to several disorders, including Huntington’s, Tourette’s syndrome, obsessive–compulsive disorders, and schizophrenia. For the study of these striatal pathologies different animal models have been used, including rodents and non-human primates. Rodents lack on morphological complexity (for example, the lack of well defined caudate and putamen nuclei), which makes it difficult to translate data to the human paradigm. Primates, and especially higher primates, are the closest model to humans, but there are ever-increasing restrictions to the use of these animals for research. In our search for a non-primate animal model with a striatum that anatomically (and perhaps functionally) can resemble that of humans, we turned our attention to the tree shrew. Evolutionary genetic studies have provided strong data supporting that the tree shrews (Scadentia) are one of the closest groups to primates, although their brain anatomy has only been studied in detail for specific brain areas. Morphologically, the tree shrew striatum resembles the primate striatum with the presence of an internal capsule separating the caudate and putamen, but little is known about its neurochemical composition. Here we analyzed the expression of calcium-binding proteins, the presence and distribution of the striosome and matrix compartments (by the use of calbindin, tyrosine hydroxylase, and acetylcholinesterase immunohistochemistry), and the GABAergic system by immunohistochemistry against glutamic acid decarboxylase and Golgi impregnation. In summary, our results show that when compared to primates, the tree shrew dorsal striatum presents striking similarities in the distribution of most of the markers studied, while presenting some marked divergences when compared to the rodent striatum. PMID:21887131

  1. Social organization in Eulipotyphla: evidence for a social shrew.

    PubMed

    Valomy, M; Hayes, L D; Schradin, C

    2015-11-01

    Shrews and their close relatives (order Eulipotyphla) are typically considered to be solitary. This impacts our understanding of mammalian social evolution: (i) the ancestor of mammals is believed to have been shrew-like, and even though Eulipotyphla are not more basal than other mammalian orders, this might have been one reason why the first mammals have been assumed to be solitary-living; (ii) Eulipotyphla are the third largest mammalian order, with hundreds of species entering comparative analyses. We review primary field studies reporting the social organization of Eulipotyphla, doing a literature research on 445 species. Primary literature was only available for 16 of the 445 species. We found 56% of the studied species to be social (38% were living in pairs), which is in sharp contrast to the 0.5 and 8% reported in other databases. We conclude that the available information indicates that shrews are more sociable than generally believed. An interesting alternative hypothesis is that the mammalian ancestor might have been pair-living. To understand the social evolution of mammals, comparative studies must be based on reliable and specific information, and more species of all orders must be studied in the field. PMID:26559515

  2. Brain mass and cranial nerve size in shrews and moles.

    PubMed

    Leitch, Duncan B; Sarko, Diana K; Catania, Kenneth C

    2014-01-01

    We investigated the relationship between body size, brain size, and fibers in selected cranial nerves in shrews and moles. Species include tiny masked shrews (S. cinereus) weighing only a few grams and much larger mole species weighing up to 90 grams. It also includes closely related species with very different sensory specializations - such as the star-nosed mole and the common, eastern mole. We found that moles and shrews have tiny optic nerves with fiber counts not correlated with body or brain size. Auditory nerves were similarly small but increased in fiber number with increasing brain and body size. Trigeminal nerve number was by far the largest and also increased with increasing brain and body size. The star-nosed mole was an outlier, with more than twice the number of trigeminal nerve fibers than any other species. Despite this hypertrophied cranial nerve, star-nosed mole brains were not larger than predicted from body size, suggesting that magnification of their somatosensory systems does not result in greater overall CNS size. PMID:25174995

  3. The lung of shrews: morphometric estimation of diffusion capacity.

    PubMed

    Gehr, P; Sehovic, S; Burri, P H; Claassen, H; Weibel, E R

    1980-04-01

    The lungs of 16 shrews from 8 species (Sorex minutus, Neomys fodiens, Suncus etruscus, Crocidura russula, C. juvenetae, C. poensis, C. flavescens, C. giffardi) ranging in body weight from 2.2 to 100 g were studied by morphometry in order to compare the structural diffusion capacity for oxygen. DL02, with the oxygen consumption, VO2, measured on the same animals. VO2 was determined by short term measurements using a respirometer. DLO2 was estimated morphometrically. Both parameters demonstrated good coincidence in their allometric behaviour, establishing further progress in structure-function relationship in the respiratory apparatus. Whereas VO2 as well as DLO2 of shrews with a body weight W greater than 5 g follow the same allometric function established for mammals in general, the values for shrews with W less than 5 g exhibit significantly higher values. It appears that the pulmonary gas exchange parenchyma of these smallest mammals is well suited to supply the organism with the comparatively high levels of O2 required by the high metabolic rates, exhibiting a structural adaptation of the lung to higher VO2. PMID:7394364

  4. Brain Mass and Cranial Nerve Size in Shrews and Moles

    PubMed Central

    Leitch, Duncan B.; Sarko, Diana K.; Catania, Kenneth C.

    2014-01-01

    We investigated the relationship between body size, brain size, and fibers in selected cranial nerves in shrews and moles. Species include tiny masked shrews (S. cinereus) weighing only a few grams and much larger mole species weighing up to 90 grams. It also includes closely related species with very different sensory specializations – such as the star-nosed mole and the common, eastern mole. We found that moles and shrews have tiny optic nerves with fiber counts not correlated with body or brain size. Auditory nerves were similarly small but increased in fiber number with increasing brain and body size. Trigeminal nerve number was by far the largest and also increased with increasing brain and body size. The star-nosed mole was an outlier, with more than twice the number of trigeminal nerve fibers than any other species. Despite this hypertrophied cranial nerve, star-nosed mole brains were not larger than predicted from body size, suggesting that magnification of their somatosensory systems does not result in greater overall CNS size. PMID:25174995

  5. Novelties of conception in insectivorous mammals (Lipotyphla), particularly shrews.

    PubMed

    Bedford, J Michael; Mock, Orin B; Goodman, Steven M

    2004-11-01

    In the order Lipotyphla (Insectivora), certain reproductive features differ quite distinctly from the eutherian norms, and are of interest with regard to the evolution of mammalian gamete function and perhaps for questions of lipotyphlan phylogeny. As seen in one or more members of five lipotyphlan families (shrews, moles, hedgehogs, golden moles, tenrecs), these features can involve the configuration of the male tract including the penis, the morphology of the sperm head, the anatomy of the oviduct and the patterns of sperm transport within it, the character of the cumulus oophorus, and the way in which fertilising spermatozoa interact with the eggs. However, the picture is by no means uniform within the order. Reproductive idiosyncrasies occur variously in the different lipotyphlan families, and appear consistently and strikingly in shrews--the group studied most extensively. Compared to the patterns in most Eutheria, the most interesting anomalies in soricids include (a) the regulation of sperm transport to the site of fertilisation by oviduct crypts, whose arrangement can vary even according to species, (b) a circumscribed matrix-free cumulus oophorus that appears essential for fertilisation as the inducer of the acrosome reaction, (c) barbs on the acrosome-reacted sperm head by which it may attach to the zona pellucida. With regard to the bearing such reproductive traits might have on lipotyphlan systematics, the African mouse shrew (Myosorex varius) displays a mix of traits that characterize either crocidurine or soricine shrews, consistent with the proposal that it belongs in a more primitive tribe, Myosoricinae, or subfamily, the Crocidosoricinae, from which the crocidurine and soricine lines probably evolved. Moreover, although elephant shrews are assigned now to a separate order (Macroscelidea), they display several of the unusual reproductive features seen in lipotyphlans, particularly in chrysochlorids and tenrecs. On the other hand, if used as a phylogenetic yardstick, none of the reproductive features described serves to define the Lipotyphla as classically constituted within one order, nor necessarily all the relationships suggested by recent sequencing studies of nuclear and mitochondrial genes. PMID:15682875

  6. NEARCTIC SHREWS, SOREX SPP., AS PARATENIC HOSTS OF SOBOLIPHYME BATURINI (NEMATODA: SOBOLIPHYMIDAE).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    : Third-stage larvae of Soboliphyme baturini were discovered for the first time in shrews, Sorex cinereus, and S. tundrensis from Alaska and the Nearctic. Shrews were found to be infected with L3 at Suloia Lake, southeastern Alaska, Togiak National Wildlife Refuge, southwestern Alaska and from the Y...

  7. Identification of Glyceraldehyde 3-Phosphate Dehydrogenase Sequence and Expression Profiles in Tree Shrew (Tupaia belangeri)

    PubMed Central

    Zheng, Yu; Wang, Yingjun; Smith, Wanli W.; Leng, Jing

    2014-01-01

    The tree shrews (Tupaia belangeri) diverged from the primate order (Primates) and are classified as Scandentia, a separate taxonomic group of mammals. The tree shrew has been suggested to use an animal model to study human disease but the genomic sequences of tree shrew is largely unidentified. Here we identified the full-length cDNA sequence of a housekeeping gene, Glyceraldehyde 3-phosphate Dehydrogenase (GAPDH), in tree shrew. We further constructed a phylogenetic family tree base on GAPDH molecules of various organisms and compared GAPDH sequences with human and other small experimental animals. These study revealed that tree shrew was closer to human than mouse, rat, rabbit and guinea pig. The Quantitative Reverse Transcription PCR and western blot analysis further demonstrated that GAPDH expressed in various tissues in tree shrew as a general conservative housekeeping proteins as in human. Our findings provide the novel genetic knowledge of the tree shrew and strong evidences that tree shrew can be an experimental model system to study human disorders. PMID:24887411

  8. Targeting of Transmembrane Protein Shrew-1 to Adherens Junctions Is Controlled by Cytoplasmic Sorting Motifs

    PubMed Central

    Jakob, Viktor; Schreiner, Alexander; Tikkanen, Ritva

    2006-01-01

    We recently identified transmembrane protein shrew-1 and showed that it is able to target to adherens junctions in polarized epithelial cells. This suggested shrew-1 possesses specific basolateral sorting motifs, which we analyzed by mutational analysis. Systematic mutation of amino acids in putative sorting signals in the cytoplasmic domain of shrew-1 revealed three tyrosines and a dileucine motif necessary for basolateral sorting. Substitution of these amino acids leads to apical localization of shrew-1. By applying tannic acid to either the apical or basolateral part of polarized epithelial cells, thereby blocking vesicle fusion with the plasma membrane, we obtained evidence that the apically localized mutants were primarily targeted to the basolateral membrane and were then redistributed to the apical domain. Further support for a postendocytic sorting mechanism of shrew-1 was obtained by demonstrating that ?1B, a subunit of the epithelial cell-specific adaptor complex AP-1B, interacts with shrew-1. In conclusion, our data provide evidence for a scenario where shrew-1 is primarily delivered to the basolateral membrane by a so far unknown mechanism. Once there, adaptor protein complex AP-1B is involved in retaining shrew-1 at the basolateral membrane by postendocytic sorting mechanisms. PMID:16707570

  9. Prevalence of SFTSV among Asian house shrews and rodents, China, January-August 2013.

    PubMed

    Liu, Jian-Wei; Wen, Hong-Ling; Fang, Li-Zhu; Zhang, Zhen-Tang; He, Shu-Ting; Xue, Zai-Feng; Ma, Dong-Qiang; Zhang, Xiao-Shuang; Wang, Tao; Yu, Hao; Zhang, Yan; Zhao, Li; Yu, Xue-jie

    2014-12-01

    To evaluate the role of small mammals as hosts of severe fever with thrombocytopenia syndrome virus (SFTSV), we tested serum samples from rodents and shrews in China, collected in 2013. SFTSV antibodies and RNA were detected, suggesting that rodents and shrews might be hosts for SFTSV. PMID:25418111

  10. Human and Tree Shrew Alpha-synuclein: Comparative cDNA Sequence and Protein Structure Analysis.

    PubMed

    Wu, Zheng-Cun; Huang, Zhang-Qiong; Jiang, Qin-Fang; Dai, Jie-Jie; Zhang, Ying; Gao, Jia-Hong; Sun, Xiao-Mei; Chen, Nai-Hong; Yuan, Yu-He; Li, Cong; Han, Yuan-Yuan; Li, Yun; Ma, Kai-Li

    2015-10-01

    The synaptic protein alpha-synuclein (?-syn) is associated with a number of neurodegenerative diseases, and homology analyses among many species have been reported. Nevertheless, little is known about the cDNA sequence and protein structure of ?-syn in tree shrews, and this information might contribute to our understanding of its role in both health and disease. We designed primers to the human ?-syn cDNA sequence; then, tree shrew ?-syn cDNA was obtained by RT-PCR and sequenced. Based on the acquired tree shrew ?-syn cDNA sequence, both the amino acid sequence and the spatial structure of ?-syn were predicted and analyzed. The homology analysis results showed that the tree shrew cDNA sequence matches the human cDNA sequence exactly except at nucleotide positions 45, 60, 65, 69, 93, 114, 147, 150, 157, 204, 252, 270, 284, 298, 308, and 324. Further protein sequence analysis revealed that the tree shrew ?-syn protein sequence is 97.1 % identical to that of human ?-syn. The secondary protein structure of tree shrew ?-syn based on random coils and ?-helices is the same as that of the human structure. The phosphorylation sites are highly conserved, except the site at position 103 of tree shrew ?-syn. The predicted spatial structure of tree shrew ?-syn is identical to that of human ?-syn. Thus, ?-syn might have a similar function in tree shrew and in human, and tree shrew might be a potential animal model for studying the pathogenesis of ?-synucleinopathies. PMID:26265394

  11. Water shrews detect movement, shape, and smell to find prey underwater.

    PubMed

    Catania, Kenneth C; Hare, James F; Campbell, Kevin L

    2008-01-15

    American water shrews (Sorex palustris) are aggressive predators that feed on a variety of terrestrial and aquatic prey. They often forage at night, diving into streams and ponds in search of food. We investigated how shrews locate submerged prey using high-speed videography, infrared lighting, and stimuli designed to mimic prey. Shrews attacked brief water movements, indicating motion is an important cue used to detect active or escaping prey. They also bit, retrieved, and attempted to eat model fish made of silicone in preference to other silicone objects showing that tactile cues are important in the absence of movement. In addition, water shrews preferentially sniffed model prey fish and crickets underwater by exhaling and reinhaling air through the nostrils, suggesting olfaction plays an important role in aquatic foraging. The possibility of echolocation, sonar, or electroreception was investigated by testing for ultrasonic and audible calls above and below water and by presenting electric fields to foraging shrews. We found no evidence for these abilities. We conclude that water shrews detect motion, shape, and smell to find prey underwater. The short latency of attacks to water movements suggests shrews may use a flush-pursuit strategy to capture some prey. PMID:18184804

  12. Water shrews detect movement, shape, and smell to find prey underwater

    PubMed Central

    Catania, Kenneth C.; Hare, James F.; Campbell, Kevin L.

    2008-01-01

    American water shrews (Sorex palustris) are aggressive predators that feed on a variety of terrestrial and aquatic prey. They often forage at night, diving into streams and ponds in search of food. We investigated how shrews locate submerged prey using high-speed videography, infrared lighting, and stimuli designed to mimic prey. Shrews attacked brief water movements, indicating motion is an important cue used to detect active or escaping prey. They also bit, retrieved, and attempted to eat model fish made of silicone in preference to other silicone objects showing that tactile cues are important in the absence of movement. In addition, water shrews preferentially sniffed model prey fish and crickets underwater by exhaling and reinhaling air through the nostrils, suggesting olfaction plays an important role in aquatic foraging. The possibility of echolocation, sonar, or electroreception was investigated by testing for ultrasonic and audible calls above and below water and by presenting electric fields to foraging shrews. We found no evidence for these abilities. We conclude that water shrews detect motion, shape, and smell to find prey underwater. The short latency of attacks to water movements suggests shrews may use a flush-pursuit strategy to capture some prey. PMID:18184804

  13. An ultrastructural and lectin-histochemical study on the seminiferous epithelium of the common tree shrew (Tupaia glis).

    PubMed Central

    Kurohmaru, M; Maeda, S; Suda, A; Hondo, E; Ogawa, K; Endo, H; Kimura, J; Yamada, J; Rerkamnuaychoke, W; Chungsamarnyart, N; Hayashi, Y; Nishida, T

    1996-01-01

    The seminiferous epithelium of the common tree shrew (Tupaia glis) was investigated using transmission electron microscopy and lectin-histochemistry. It was compared with that of shrews examined in previous studies. Some peculiar structures were detected in the tree shrew spermatid at the electron microscopic level. The most characteristic feature was the disposition of mitochondria in early spermatids. In cap and early acrosome-phase spermatids, mitochondria accumulated in one area of the spermatid cytoplasm and then dispersed in the late acrosome phase. Subsequently they again clustered to form the middle piece of spermatozoa. While the lamellar structure was clearly seen in the caudal region of the spermatid nucleus, it gradually disappeared during the process of elongation. The dilated area in the postacrosomal space of early round spermatids was also characteristic. The dilation was not detected in elongated spermatids. These structures were not recognised in the seminiferous epithelium of shrews. With respect to lectin histochemistry, the binding patterns in the spermatid acrosome of the tree shrew were similar to those of the musk shrew. However, PNA and BPA, which reacted with the Sertoli cell cytoplasm of the musk shrew, showed no reaction in the tree shrew Sertoli cell. Thus, except for some lectin binding patterns in the spermatid acrosome, no close similarity was recognised in the morphology of the seminiferous epithelium between tree shrews and shrews. Images Fig. 1 Fig. 2 Fig. 4 Fig. 5 PMID:8771399

  14. Microchip-associated sarcoma in a shrew (Suncus murinus).

    PubMed

    Schutt, Leah K; Turner, Patricia V

    2010-09-01

    A 16-mo-old female house musk shrew (Suncus murinus) with a 1-wk history of a rapidly growing subcutaneous mass in the interscapsular region was euthanized and submitted for necropsy. Macroscopic examination identified an irregular, well-demarcated, solid, tan-white subcutaneous mass. A small cavity containing a microchip device was present at the center of the mass. In addition, massive splenomegaly was evident grossly. Histologically, the subcutaneous mass comprised spindle cells arranged in a storiform pattern of interweaving bundles, consistent with a high-grade soft tissue sarcoma with multifocal necrosis. Immunohistochemical investigation suggested that the neoplastic cells were positive for neuron-specific enolase and (rarely) ?-smooth muscle actin and negative for cytokeratin, desmin, S100, and vimentin. In light of the mesenchymal histopathologic phenotype and the lack of specific immunoreactivity pattern, the mass was considered to be most consistent with a poorly differentiated sarcoma. To our knowledge, this is the first report of a microchip-associated soft tissue sarcoma in a shrew. PMID:20858367

  15. Biodiversity and evolution of Imjin virus and Thottapalayam virus in Crocidurinae shrews in Zhejiang Province, China.

    PubMed

    Lin, Xian-Dan; Zhou, Run-Hong; Fan, Fei-Neng; Ying, Xu-Hua; Sun, Xiao-Yu; Wang, Wen; Holmes, Edward C; Zhang, Yong-Zhen

    2014-08-30

    The recent discovery of numerous hantaviruses in insectivores has provided a new view of hantavirus biodiversity and evolution. To determine the presence and genetic diversity of Imjin virus (MJNV) and Thottapalayam virus (TPMV) in insectivores in Zhejiang Province, China, we captured and performed virus screening of 32 Ussuri white-toothed shrews (Crocidura lasiura) and 105 Asian house shrews (Suncus murinus) in different coastal regions. Hantavirus genome (S, M, and L segments) sequences were successfully recovered from one Ussuri white-toothed shrew and seven Asian house shrews. Phylogenetic analysis revealed that the virus carried by the Ussuri white-toothed shrew was most closely related to MJNV, but with >15% nucleotide sequence difference, suggesting that it represents a new subtype. The hantaviruses carried by Asian house shrews were closely related to the TPMV variants found in the same geographic area, but more distantly related to those sampled in India and Nepal. Additionally, the TPMV sequences obtained in this study, as well as those found previously in this area, could be divided into three lineages reflecting their geographic origins, indicative of largely allopatric evolution. Overall, our data highlights the high genetic diversity of insectivore-borne hantaviruses in China, suggesting that more may be discovered in the future. PMID:24874196

  16. On the origin, homologies and evolution of primate facial muscles, with a particular focus on hominoids and a suggested unifying nomenclature for the facial muscles of the Mammalia

    PubMed Central

    Diogo, R; Wood, B A; Aziz, M A; Burrows, A

    2009-01-01

    The mammalian facial muscles are a subgroup of hyoid muscles (i.e. muscles innervated by cranial nerve VII). They are usually attached to freely movable skin and are responsible for facial expressions. In this study we provide an account of the origin, homologies and evolution of the primate facial muscles, based on dissections of various primate and non-primate taxa and a review of the literature. We provide data not previously reported, including photographs showing in detail the facial muscles of primates such as gibbons and orangutans. We show that the facial muscles usually present in strepsirhines are basically the same muscles that are present in non-primate mammals such as tree-shrews. The exceptions are that strepsirhines often have a muscle that is usually not differentiated in tree-shrews, the depressor supercilii, and lack two muscles that are usually differentiated in these mammals, the zygomatico-orbicularis and sphincter colli superficialis. Monkeys such as macaques usually lack two muscles that are often present in strepsirhines, the sphincter colli profundus and mandibulo-auricularis, but have some muscles that are usually absent as distinct structures in non-anthropoid primates, e.g. the levator labii superioris alaeque nasi, levator labii superioris, nasalis, depressor septi nasi, depressor anguli oris and depressor labii inferioris. In turn, macaques typically lack a risorius, auricularis anterior and temporoparietalis, which are found in hominoids such as humans, but have muscles that are usually not differentiated in members of some hominoid taxa, e.g. the platysma cervicale (usually not differentiated in orangutans, panins and humans) and auricularis posterior (usually not differentiated in orangutans). Based on our observations, comparisons and review of the literature, we propose a unifying, coherent nomenclature for the facial muscles of the Mammalia as a whole and provide a list of more than 300 synonyms that have been used in the literature to designate the facial muscles of primates and other mammals. A main advantage of this nomenclature is that it combines, and thus creates a bridge between, those names used by human anatomists and the names often employed in the literature dealing with non-human primates and non-primate mammals. PMID:19531159

  17. Thermoregulatory correlates of nausea in rats and musk shrews

    PubMed Central

    Ngampramuan, Sukonthar; Cerri, Matteo; Vecchio, Flavia Del; Corrigan, Joshua J.; Kamphee, Amornrat; Dragic, Alexander S.; Rudd, John A.; Romanovsky, Andrej A.; Nalivaiko, Eugene

    2014-01-01

    Nausea is a prominent symptom and major cause of complaint for patients receiving anticancer chemo- or radiation therapy. The arsenal of anti-nausea drugs is limited, and their efficacy is questionable. Currently, the development of new compounds with anti-nausea activity is hampered by the lack of physiological correlates of nausea. Physiological correlates are needed because common laboratory rodents lack the vomiting reflex. Furthermore, nausea does not always lead to vomiting. Here, we report the results of studies conducted in four research centers to investigate whether nausea is associated with any specific thermoregulatory symptoms. Two species were studied: the laboratory rat, which has no vomiting reflex, and the house musk shrew (Suncus murinus), which does have a vomiting reflex. In rats, motion sickness was induced by rotating them in their individual cages in the horizontal plane (0.75 Hz, 40 min) and confirmed by reduced food consumption at the onset of dark (active) phase. In 100% of rats tested at three centers, post-rotational sickness was associated with marked (~1.5C) hypothermia, which was associated with a short-lasting tail-skin vasodilation (skin temperature increased by ~4C). Pretreatment with ondansetron, a serotonin 5-HT3 receptor antagonist, which is used to treat nausea in patients in chemo- or radiation therapy, attenuated hypothermia by ~30%. In shrews, motion sickness was induced by a cyclical back-and-forth motion (4 cm, 1 Hz, 15 min) and confirmed by the presence of retching and vomiting. In this model, sickness was also accompanied by marked hypothermia (~2C). Like in rats, the hypothermic response was preceded by transient tail-skin vasodilation. In conclusion, motion sickness is accompanied by hypothermia that involves both autonomic and thermoeffector mechanisms: tail-skin vasodilation and possibly reduction of the interscapular brown adipose tissue activity. These thermoregulatory symptoms may serve as physiological correlates of nausea. PMID:24728971

  18. Identification and Characterization of Liver MicroRNAs of the Chinese Tree Shrew via Deep Sequencing

    PubMed Central

    Feng, Yue; Feng, Yue-Mei; Feng, Yang; Lu, Caixia; Liu, Li; Sun, Xiaomei; Dai, Jiejie; Xia, Xueshan

    2015-01-01

    Background: Chinese tree shrew (Tupaia belangeri chinensis) is a small animal that possess many features, which are valuable in biomedical research, as experimental models. Currently, there are numerous attempts to utilize tree shrews as models for hepatitis C virus (HCV) infection. Objectives: This study aimed to construct a liver microRNA (miRNA) data of the tree shrew. Materials and Methods: Three second filial generation tree shrews were used in this study. Total RNA was extracted from each liver of the tree shrew and equal quality mixed, then reverse-transcribed to complementary DNA (cDNA). The cDNAs were amplified by polymerase chain reaction and subjected to high-throughput sequencing. Results: A total of 2060 conserved miRNAs were identified through alignment with the mature miRNAs in miRBase 20.0 database. The gene ontology and Kyoto encyclopedia of genes and genomes analyses of the target genes of the miRNAs revealed several candidate miRNAs, genes and pathways that may involve in the process of HCV infection. The abundance of miR-122 and Let-7 families and their other characteristics provided us more evidences for the utilization of this animal, as a potential model for HCV infection and other related biomedical research. Moreover, 80 novel microRNAs were predicted using the software Mireap. The top 3 abundant miRNAs were validated in other tree samples, based on stem-loop quantitative reverse transcription-polymerase chain reaction. Conclusions: According to the liver microRNA data of Chinese tree shrew, characteristics of the miR-122 and Let-7 families further highlight the suitability of tree shrew as the animal model in HCV research. PMID:26587035

  19. Distribution of corticotropin-releasing factor in the tree shrew brain.

    PubMed

    Shu, Yu-Mian; Ni, Rong-Jun; Sun, Yun-Jun; Fang, Hui; Zhou, Jiang-Ning

    2015-08-27

    Corticotropin-releasing factor (CRF) in the brain plays an important role in regulations of physiological and behavioral processes, yet CRF distribution in tree shrew brain has not been thoroughly and systematically reported. Here we examined the distribution of CRF immunoreactivity in the brain of tree shrews (Tupaia belangeri chinensis) using immunohistochemical techniques. CRF-immunoreactive (-ir) cells and fibers were present in the rhinencephalon, telencephalon, diencephalon, mesencephalon, metencephalon and myelencephalon of saline- and colchicine-treated tree shrews. Laminar distribution of CRF-ir cells was found in the main olfactory bulb and neocortex. Compared with saline-treated tree shrews, a larger number of CRF-ir cells in colchicine-treated tree shrews were found in the bed nucleus of the stria terminalis, paraventricular hypothalamic nucleus, medial preoptic area, dorsomedial hypothalamic nucleus, reuniens thalamic nucleus, inferior colliculus, Edinger-Westphal nucleus, median raphe nucleus, locus coeruleus, parabrachial nucleus, dorsal tegmental nucleus, lateral reticular nucleus, and inferior olive. CRF-ir fibers from the hypothalamic paraventricular nucleus projected toward and through the internal zone of the median eminence. In addition, density of CRF immunoreactivity is significantly different in the bed nucleus of the stria terminalis, central amygdaloid nucleus, suprachiasmatic nucleus, median raphe nucleus, Edinger-Westphal nucleus, locus coeruleus and inferior olive between tree shrews and rats after saline or colchicine treatment. Our findings provide, for the first time, the comprehensive description of CRF immunoreactivity and whole brain mapping of CRF in tree shrews, which is an anatomical basis for the participation of CRF system in the regulation of numerous behaviors. PMID:26074350

  20. Physical and Cognitive Performance of the Least Shrew (Cryptotis parva) on a Calcium-Restricted Diet.

    PubMed

    Czajka, Jessica L; McCay, Timothy S; Garneau, Danielle E

    2012-09-01

    Geological substrates and air pollution affect the availability of calcium to mammals in many habitats, including the Adirondack Mountain Region (Adirondacks) of the United States. Mammalian insectivores, such as shrews, may be particularly restricted in environments with low calcium. We examined the consequences of calcium restriction on the least shrew (Cryptotis parva) in the laboratory. We maintained one group of shrews (5 F, 5 M) on a mealworm diet with a calcium concentration comparable to beetle larvae collected in the Adirondacks (1.1 0.3 mg/g) and another group (5 F, 3 M) on a mealworm diet with a calcium concentration almost 20 times higher (19.5 5.1 mg/g). Animals were given no access to mineral sources of calcium, such as snail shell or bone. We measured running speed and performance in a complex maze over 10 weeks. Shrews on the high-calcium diet made fewer errors in the maze than shrews on the low-calcium diet (F1,14 = 12.8, p < 0.01). Females made fewer errors than males (F1,14 = 10.6, p < 0.01). Running speeds did not markedly vary between diet groups or sexes, though there was a trend toward faster running by shrews on the high calcium diet (p = 0.087). Shrews in calcium-poor habitats with low availability of mineral sources of calcium may have greater difficulty with cognitive tasks such as navigation and recovery of food hoards. PMID:25379219

  1. Physical and Cognitive Performance of the Least Shrew (Cryptotis parva) on a Calcium-Restricted Diet

    PubMed Central

    Czajka, Jessica L.; McCay, Timothy S.; Garneau, Danielle E.

    2012-01-01

    Geological substrates and air pollution affect the availability of calcium to mammals in many habitats, including the Adirondack Mountain Region (Adirondacks) of the United States. Mammalian insectivores, such as shrews, may be particularly restricted in environments with low calcium. We examined the consequences of calcium restriction on the least shrew (Cryptotis parva) in the laboratory. We maintained one group of shrews (5 F, 5 M) on a mealworm diet with a calcium concentration comparable to beetle larvae collected in the Adirondacks (1.1 0.3 mg/g) and another group (5 F, 3 M) on a mealworm diet with a calcium concentration almost 20 times higher (19.5 5.1 mg/g). Animals were given no access to mineral sources of calcium, such as snail shell or bone. We measured running speed and performance in a complex maze over 10 weeks. Shrews on the high-calcium diet made fewer errors in the maze than shrews on the low-calcium diet (F1,14 = 12.8, p < 0.01). Females made fewer errors than males (F1,14 = 10.6, p < 0.01). Running speeds did not markedly vary between diet groups or sexes, though there was a trend toward faster running by shrews on the high calcium diet (p = 0.087). Shrews in calcium-poor habitats with low availability of mineral sources of calcium may have greater difficulty with cognitive tasks such as navigation and recovery of food hoards. PMID:25379219

  2. Neuropeptide Y influences acute food intake and energy status affects NPY immunoreactivity in the female musk shrew (Suncus murinus) 1

    PubMed Central

    Bojkowska, Karolina; Hamczyk, Magdalena M.; Tsai, Houng-Wei; Riggan, Anna; Rissman, Emilie F.

    2008-01-01

    Neuropeptide Y (NPY) stimulates feeding, depresses sexual behavior, and its expression in the brain is modulated by energetic status. We examined the role of NPY in female musk shrews, a species with high energetic and reproductive demands; they store little fat, and small changes in energy can rapidly diminish or enhance sexual receptivity. Intracerebroventricular infusion of NPY enhanced acute food intake in shrews, however, NPY had little affect on sexual receptivity. The distribution of NPY immunoreactivity in the female musk shrew brain was unremarkable, but energy status differentially affected NPY immunoreactivity in several regions. Similar to what has been noted in other species, NPY immunoreactivity was less dense in brains of ad libitum shrews and greater in shrews subjected to food restriction. In two midbrain regions, both of which contain high levels of gonadotropin releasing hormone II (GnRH II) which has anorexigenic actions in shrews, NPY immunoreactivity was more sensitive to changes in food intake. In these regions, acute refeeding (90180 minutes) after food restriction reduced NPY immunoreactivity to levels noted in ad libitum shrews. We hypothesize that interactions between NPY and GnRH II maintain energy homeostasis and reproduction in the musk shrew. PMID:18191134

  3. Body temperature patterns in two syntopic elephant shrew species during winter.

    PubMed

    Boyles, Justin G; Smit, Ben; Sole, Catherine L; McKechnie, Andrew E

    2012-01-01

    We measured body temperature (T(b)) in free-ranging individuals of two species of elephant shrews, namely western rock elephant shrews (Elephantulus rupestris) and Cape rock elephant shrews (E. edwardii), during winter in a winter-rainfall region of western South Africa. These syntopic species have similar ecologies and morphologies and thus potential for large overlaps in diet and habitat use. Unexpectedly, they displayed different T(b) patterns. Western rock elephant shrews were heterothermic, with all individuals decreasing T(b) below 30C on at least 34% of nights. The level of heterothermy expressed was similar to other species traditionally defined as daily heterotherms and was inversely related to T(a), as is commonly seen in small heterothermic endotherms. In contrast, Cape rock elephant shrews rarely allowed their T(b) to decrease below 30C. The level of heterothermy was similar to species traditionally defined as homeotherms and there was no relationship between the level of heterothermy expressed and T(a). In both species, the minimum daily T(b) was recorded almost exclusively at night, often shortly before sunrise, although in some individuals minimum T(b) occasionally occurred during the day. The interspecific variation in T(b) patterns among Elephantulus species recorded to date reiterates the importance of ecological determinants of heterothermy that interact with factors such as body mass and phylogeny. PMID:21964153

  4. Factors influencing the variation in capture rates of shrews in southern California, USA

    USGS Publications Warehouse

    Laakkonen, J.; Fisher, R.N.; Case, T.J.

    2003-01-01

    We examined the temporal variation in capture rates of shrews Notiosorex crawfordi (Coues, 1877) and Sorex ornatus (Merriam, 1895) in 20 sites representing fragmented and continuous habitats in southern California, USA. In N. crawfordi, the temporal variation was significantly correlated with the mean capture rates. Of the 6 landscape variables analyzed (size of the landscape, size of the sample area, altitude, edge, longitude and latitude), sample area was positively correlated with variation in capture rates of N. crawfordi. In S. ornatus, longitude was negatively correlated with variation in capture rates. Analysis of the effect of precipitation on the short- and long-term capture rates at 2 of the sites showed no correlation between rainfall and capture rates of shrews even though peak number of shrews at both sites were reached during the year of highest amount of rainfall. A key problem confounding capture rates of shrews in southern California is the low overall abundance of both shrew species in all habitats and seasons.

  5. Shedding of Infectious Borna Disease Virus-1 in Living Bicolored White-Toothed Shrews

    PubMed Central

    Nobach, Daniel; Bourg, Manon; Herzog, Sibylle; Lange-Herbst, Hildburg; Encarnação, Jorge A.; Eickmann, Markus; Herden, Christiane

    2015-01-01

    Background Many RNA viruses arise from animal reservoirs, namely bats, rodents and insectivores but mechanisms of virus maintenance and transmission still need to be addressed. The bicolored white-toothed shrew (Crocidura leucodon) has recently been identified as reservoir of the neurotropic Borna disease virus 1 (BoDV-1). Principal Findings Six out of eleven wild living bicoloured white-toothed shrews were trapped and revealed to be naturally infected with BoDV-1. All shrews were monitored in captivity in a long-term study over a time period up to 600 days that differed between the individual shrews. Interestingly, all six animals showed an asymptomatic course of infection despite virus shedding via various routes indicating a highly adapted host-pathogen interaction. Infectious virus and viral RNA were demonstrated in saliva, urine, skin swabs, lacrimal fluid and faeces, both during the first 8 weeks of the investigation period and for long time shedding after more than 250 days in captivity. Conclusions The various ways of shedding ensure successful virus maintenance in the reservoir population but also transmission to accidental hosts such as horses and sheep. Naturally BoDV-1-infected living shrews serve as excellent tool to unravel host and pathogen factors responsible for persistent viral co-existence in reservoir species while maintaining their physiological integrity despite high viral load in many organ systems. PMID:26313904

  6. [Cloning of full-length coding sequence of tree shrew CD3E and prediction of its molecular characteristics].

    PubMed

    Li, Yi-Jiang; Gao, Yue-Dong; Guo, Yan; Lu, Cai-Xia; Huang, Jing-Fei; Xia, Xue-Shan; Dai, Jie-Jie; Fan, Quan-Shui; Li, Zuo-Sheng; Zhang, Hua-Tang

    2010-10-01

    The use of tree shrews (Tupaia belangeri) in human disease studies demands essential research tools, in particular cellular markers and their monoclonal antibodies for immunological studies. Here we cloned the full-length cDNAs encoding CD3E from total RNA of the spleen, liver and peripheral blood of tree shrews and analyzed their structural characteristics in comparison with other mammals by Discovery Studio software. The results showed that the open reading frame sequence of tree shrew CD3E was 582 bp, encoding 194 amino acids. The overall structure of tree shrew CD3E protein was similar to its counterparts of other mammals, intracellular and transmembrane domain highly conserved. However, detailed analysis revealed two potential glycosylation sites and different surface charges in the extracellular domain. Availability of the entire open-reading-frame and related sequence information would therefore facilitate the preparation of monoclonal antibodies against tree shrew CD3 and further studies for its function. PMID:20979250

  7. Tuning of color contrast signals to visual sensitivity maxima of tree shrews by three Bornean highland Nepenthes species.

    PubMed

    Moran, Jonathan A; Clarke, Charles; Greenwood, Melinda; Chin, Lijin

    2012-10-01

    Three species of Nepenthes pitcher plants (Nepenthes rajah, Nepenthes lowii and Nepenthes macrophylla) specialize in harvesting nutrients from tree shrew excreta in their pitchers. In all three species, nectaries on the underside of the pitcher lid are the focus of the tree shrews' attention. Tree shrews are dichromats, with visual sensitivity in the blue and green wavebands. All three Nepenthes species were shown to produce visual signals, in which the underside of the pitcher lid (the area of highest nectar production) stood out in high contrast to the adjacent area on the pitcher (i.e., was brighter), in the blue and green wavebands visible to the tree shrews. N. rajah showed the tightest degree of "tuning," notably in the green waveband. Conversely, pitchers of Nepenthes burbidgeae, a typical insectivorous species sympatric with N. rajah, did not produce a color pattern tuned to tree shrew sensitivity maxima. PMID:22902686

  8. High shrew diversity on Alaska's Seward Peninsula: Community assembly and environmental change

    USGS Publications Warehouse

    Hope, Andrew G.

    2012-01-01

    In September 2010, 6 species of shrews (genus: Sorex) were collected at a single locality on the Seward Peninsula of Alaska. Such high sympatric diversity within a single mammalian genus is seldom realized. This phenomenon at high latitudes highlights complex Arctic community dynamics that reflect significant turnover through time as a consequence of environmental change. Each of these shrew species occupies a broad geographic distribution collectively spanning the entire Holarctic, although the study site lies within Eastern Beringia, near the periphery of all individual ranges. A review of published genetic evidence reflects a depauperate shrew community within ice-free Beringia through the last glaciation, and recent assembly of current diversity during the Holocene.

  9. Isolation and characterization of a novel arenavirus harbored by Rodents and Shrews in Zhejiang province, China.

    PubMed

    Li, Kun; Lin, Xian-Dan; Wang, Wen; Shi, Mang; Guo, Wen-Ping; Zhang, Xiao-He; Xing, Jian-Guang; He, Jin-Rong; Wang, Ke; Li, Ming-Hui; Cao, Jian-Hai; Jiang, Mu-Liu; Holmes, Edward C; Zhang, Yong-Zhen

    2015-02-01

    To determine the biodiversity of arenaviruses in China, we captured and screened rodents and shrews in Wenzhou city, Zhejiang province, a locality where hemorrhagic fever diseases are endemic in humans. Accordingly, arenaviruses were detected in 42 of 351 rodents from eight species, and in 12 of 272 Asian house shrews (Suncus murinus), by RT-PCR targeting the L segment. From these, a single arenavirus was successfully isolated in cell culture. The virion particles exhibited a typical arenavirus morphology under transmission electron microscopy. Comparison of the S and L segment sequences revealed high levels of nucleotide (>32.2% and >39.6%) and amino acid (>28.8% and >43.8%) sequence differences from known arenaviruses, suggesting that it represents a novel arenavirus, which we designated Wenzhou virus (WENV). Phylogenetic analysis revealed that all WENV strains harbored by both rodents and Asian house shrews formed a distinct lineage most closely related to Old World arenaviruses. PMID:25506671

  10. Etruscan shrew muscle: the consequences of being small.

    PubMed

    Jrgens, Klaus D

    2002-08-01

    The skeletal muscles of the smallest mammal, the Etruscan shrew Suncus etruscus, are functionally and structurally adapted to the requirements of an enormously high energy turnover. Isometric twitch contractions of the extensor digitorum longus (EDL) and soleus muscles are shorter than in any other mammal, allowing these muscles to contract at outstandingly high frequencies. The skeletal muscles of S. etruscus contract at up to 900 min(-1) for respiration, up to 780 min(-1) for running and up to 3500 min(-1) for shivering. All skeletal muscles investigated lack slow-twitch type I fibres and consist only of fast-twitch type IID fibres. These fibres are optimally equipped with properties enabling a high rate of almost purely oxidative metabolism: they have a small diameter, their citrate synthase activity is higher and their lactate dehydrogenase activity is lower than in the muscles of any other mammal and they have a rapid shortening velocity. Differences in isometric twitch contraction times between different muscles are, at least in part, probably due to differences in cytosolic creatine kinase activities. PMID:12110649

  11. Muscle Senescence in Short-Lived Wild Mammals, the Soricine Shrews Blarina brevicauda and Sorex palustris

    PubMed Central

    HINDLE, ALLYSON G.; LAWLER, JOHN M.; CAMPBELL, KEVIN L.; HORNING, MARKUS

    2015-01-01

    Red-toothed (soricine) shrews are consummate predators exhibiting the highest energy turnovers and shortest life spans (ca. 18 months) of any mammal, yet virtually nothing is known regarding their physiological aging. We assessed the emerging pattern of skeletal muscle senescence (contractile/connective tissue components) in sympatric species, the semi-aquatic water shrew (WS), Sorex palustris, and the terrestrial short-tailed shrew (STS), Blarina brevicauda, to determine if muscle aging occurs in wild, short-lived mammals (H0: shrews do not survive to an age where senescence occurs), and if so, whether these alterations are species-specific. Gracilis muscles were collected from first-year (n = 17) and second-year (n = 17) field-caught shrews. Consistent with typical mammalian aging, collagen content (% area) increased with age in both species (S. palustris: ~50%; B. brevicauda: ~60%). Muscle was dominated by stiffer Type I collagen, and the ratio of collagen Type I:Type III more than doubled with age. The area ratio of muscle:collagen decreased with age in both species, but was considerably lower in adult STS, suggesting species-specificity of senescence. Extracellular space was age-elevated in B. brevicauda, but was preserved in S. palustris (~50 vs. 10% elevation). Though juvenile interspecific comparisons revealed no significance, adult WS myocytes had 68% larger cross-sectional area and occurred at 28% lower fibers/area than those of adult STS. We demonstrate that age-related muscle senescence does occur in wild-caught, short-lived mammals, and we therefore reject this classic aging theory tenet. Our findings moreover illustrate that differential age adjustments in contractile/connective tissue components of muscle occur in the two species of wild-caught shrews. PMID:19296507

  12. New records of Merriams Shrew (Sorex merriami) from western North Dakota

    USGS Publications Warehouse

    M. J.Shaughnessy Jr.; Woodman, Neal

    2015-01-01

    Despite having a broad geographic distribution, Merriam's Shrew (Sorex merriami Dobson 1890) is known from a relatively few, widely-scattered localities. In North Dakota, the species was known from only a single poorly-preserved specimen collected in 1913 near Medora. We recently collected two new specimens of Merriam's Shrew from Billings and McKenzie counties in the western quarter of the state. These specimens confirm the presence of S. merriami in North Dakota and better define the northeastern edge of the species' distribution.

  13. Molecular evolution of Azagny virus, a newfound hantavirus harbored by the West African pygmy shrew (Crocidura obscurior) in Cte d'Ivoire

    PubMed Central

    2011-01-01

    Background Tanganya virus (TGNV), the only shrew-associated hantavirus reported to date from sub-Saharan Africa, is harbored by the Therese's shrew (Crocidura theresae), and is phylogenetically distinct from Thottapalayam virus (TPMV) in the Asian house shrew (Suncus murinus) and Imjin virus (MJNV) in the Ussuri white-toothed shrew (Crocidura lasiura). The existence of myriad soricid-borne hantaviruses in Eurasia and North America would predict the presence of additional hantaviruses in sub-Saharan Africa, where multiple shrew lineages have evolved and diversified. Methods Lung tissues, collected in RNAlater, from 39 Buettikofer's shrews (Crocidura buettikoferi), 5 Jouvenet's shrews (Crocidura jouvenetae), 9 West African pygmy shrews (Crocidura obscurior) and 21 African giant shrews (Crocidura olivieri) captured in Cte d'Ivoire during 2009, were systematically examined for hantavirus RNA by RT-PCR. Results A genetically distinct hantavirus, designated Azagny virus (AZGV), was detected in the West African pygmy shrew. Phylogenetic analysis of the S, M and L segments, using maximum-likelihood and Bayesian methods, under the GTR+I+? model of evolution, showed that AZGV shared a common ancestry with TGNV and was more closely related to hantaviruses harbored by soricine shrews than to TPMV and MJNV. That is, AZGV in the West African pygmy shrew, like TGNV in the Therese's shrew, did not form a monophyletic group with TPMV and MJNV, which were deeply divergent and basal to other rodent- and soricomorph-borne hantaviruses. Ancestral distributions of each hantavirus lineage, reconstructed using Mesquite 2.74, suggested that the common ancestor of all hantaviruses was most likely of Eurasian, not African, origin. Conclusions Genome-wide analysis of many more hantaviruses from sub-Saharan Africa are required to better understand how the biogeographic origin and radiation of African shrews might have contributed to, or have resulted from, the evolution of hantaviruses. PMID:21798050

  14. Evaluating the phylogenetic position of Chinese tree shrew (Tupaia belangeri chinensis) based on complete mitochondrial genome: implication for using tree shrew as an alternative experimental animal to primates in biomedical research.

    PubMed

    Xu, Ling; Chen, Shi-Yi; Nie, Wen-Hui; Jiang, Xue-Long; Yao, Yong-Gang

    2012-03-20

    Tree shrew (Tupaia belangeri) is currently placed in Order Scandentia and has a wide distribution in Southeast Asia and Southwest China. Due to its unique characteristics, such as small body size, high brain-to-body mass ratio, short reproductive cycle and life span, and low-cost of maintenance, tree shrew has been proposed to be an alternative experimental animal to primates in biomedical research. However, there are some debates regarding the exact phylogenetic affinity of tree shrew to primates. In this study, we determined the mtDNA entire genomes of three Chinese tree shrews (T. belangeri chinensis) and one Malayan flying lemur (Galeopterus variegatus). Combined with the published data for species in Euarchonta, we intended to discern the phylogenetic relationship among representative species of Dermoptera, Scandentia and Primates. The mtDNA genomes of Chinese tree shrews and Malayan flying lemur shared similar gene organization and structure with those of other mammals. Phylogenetic analysis based on 12 concatenated mitochondrial protein-encoding genes revealed a closer relationship between species of Scandentia and Glires, whereas species of Dermoptera were clustered with Primates. This pattern was consistent with previously reported phylogeny based on mtDNA data, but differed from the one reconstructed on the basis of nuclear genes. Our result suggested that the matrilineal affinity of tree shrew to primates may not be as close as we had thought. The ongoing project for sequencing the entire genome of Chinese tree shrew will provide more information to clarify this important issue. PMID:22464472

  15. Serum concentrations of thyroid hormones and activity of iodothyronine deiodinase in peripheral tissues of the house musk shrew, Suncus murinus.

    PubMed

    Tsukahara, F; Muraki, T; Nomoto, T

    1990-04-01

    Serum concentrations of thyroid hormones and the properties of iodothyronine deiodinase in tissues of the house musk shrew, Suncus murinus, were examined and compared with those of the rat. Serum concentrations of thyroxine (T4) and 3,3',5'-tri-iodothyronine (rT3) were higher, while the serum concentration of 3,5,3'-tri-iodothyronine (T3) was lower in the shrew than in the rat. Among liver, kidney, skeletal muscle, heart, brown adipose tissue (BAT), spleen, lung, testes and thymus homogenates of the shrew, T(4)5'-deiodinase (5'D) activity was highest in BAT, and rT3 5'D activity was highest in both the liver and BAT. Intermediate or low T3 5-deiodinase activity was noted in all tissues examined. Activity of 5'D for T4 and rT3 in liver and kidney was much lower, while that of BAT was much higher in the shrew than in the rat. Liver and kidney 5'D may be type-I and that of BAT may be type-II in the shrew, judging from its response to 6-n-propyl-2-thiouracil and iopanoic acid and substrate preference. Thus 5'D of the shrew was similar to that of the rat in type, but was different with respect to its activity in some peripheral tissues. This difference may have relevance to the low T3 state of the shrew. PMID:2338528

  16. The Bicolored White-Toothed Shrew Crocidura leucodon (HERMANN 1780) Is an Indigenous Host of Mammalian Borna Disease Virus

    PubMed Central

    Drrwald, Ralf; Kolodziejek, Jolanta; Weissenbck, Herbert; Nowotny, Norbert

    2014-01-01

    Borna disease (BD) is a sporadic neurologic disease of horses and sheep caused by mammalian Borna disease virus (BDV). Its unique epidemiological features include: limited occurrence in certain endemic regions of central Europe, yearly varying disease peaks, and a seasonal pattern with higher disease frequencies in spring and a disease nadir in autumn. It is most probably not directly transmitted between horses and sheep. All these features led to the assumption that an indigenous virus reservoir of BDV other than horses and sheep may exist. The search for such a reservoir had been unsuccessful until a few years ago five BDV-infected shrews were found in a BD-endemic area in Switzerland. So far, these data lacked further confirmation. We therefore initiated a study in shrews in endemic areas of Germany. Within five years 107 shrews of five different species were collected. BDV infections were identified in 14 individuals of the species bicolored white-toothed shrew (Crocidura leucodon, HERMANN 1780), all originating from BD-endemic territories. Immunohistological analysis showed widespread distribution of BDV antigen both in the nervous system and in epithelial and mesenchymal tissues without pathological alterations. Large amounts of virus, demonstrated by presence of viral antigen in epithelial cells of the oral cavity and in keratinocytes of the skin, may be a source of infection for natural and spill-over hosts. Genetic analyses reflected a close relationship of the BDV sequences obtained from the shrews with the regional BDV cluster. At one location a high percentage of BDV-positive shrews was identified in four consecutive years, which points towards a self-sustaining infection cycle in bicolored white-toothed shrews. Analyses of behavioral and population features of this shrew species revealed that the bicolored white-toothed shrew may indeed play an important role as an indigenous host of BDV. PMID:24699636

  17. The bicolored white-toothed shrew Crocidura leucodon (HERMANN 1780) is an indigenous host of mammalian Borna disease virus.

    PubMed

    Dürrwald, Ralf; Kolodziejek, Jolanta; Weissenböck, Herbert; Nowotny, Norbert

    2014-01-01

    Borna disease (BD) is a sporadic neurologic disease of horses and sheep caused by mammalian Borna disease virus (BDV). Its unique epidemiological features include: limited occurrence in certain endemic regions of central Europe, yearly varying disease peaks, and a seasonal pattern with higher disease frequencies in spring and a disease nadir in autumn. It is most probably not directly transmitted between horses and sheep. All these features led to the assumption that an indigenous virus reservoir of BDV other than horses and sheep may exist. The search for such a reservoir had been unsuccessful until a few years ago five BDV-infected shrews were found in a BD-endemic area in Switzerland. So far, these data lacked further confirmation. We therefore initiated a study in shrews in endemic areas of Germany. Within five years 107 shrews of five different species were collected. BDV infections were identified in 14 individuals of the species bicolored white-toothed shrew (Crocidura leucodon, HERMANN 1780), all originating from BD-endemic territories. Immunohistological analysis showed widespread distribution of BDV antigen both in the nervous system and in epithelial and mesenchymal tissues without pathological alterations. Large amounts of virus, demonstrated by presence of viral antigen in epithelial cells of the oral cavity and in keratinocytes of the skin, may be a source of infection for natural and spill-over hosts. Genetic analyses reflected a close relationship of the BDV sequences obtained from the shrews with the regional BDV cluster. At one location a high percentage of BDV-positive shrews was identified in four consecutive years, which points towards a self-sustaining infection cycle in bicolored white-toothed shrews. Analyses of behavioral and population features of this shrew species revealed that the bicolored white-toothed shrew may indeed play an important role as an indigenous host of BDV. PMID:24699636

  18. Generation and characterization of a breast carcinoma model by PyMT overexpression in mammary epithelial cells of tree shrew, an animal close to primates in evolution.

    PubMed

    Ge, Guang-Zhe; Xia, Hou-Jun; He, Bao-Li; Zhang, Hai-Lin; Liu, Wen-Jing; Shao, Ming; Wang, Chun-Yan; Xiao, Ji; Ge, Fei; Li, Fu-Bing; Li, Yi; Chen, Ceshi

    2016-02-01

    The tree shrew is becoming an attractive experimental animal model for human breast cancer owing to a closer relationship to primates/humans than rodents. Tree shrews are superior to classical primates because tree shrew are easier to manipulate, maintain and propagate. It is required to establish a high-efficiency tree shrew breast cancer model for etiological research and drug assessment. Our previous studies suggest that 7,12-dimethylbenz(a)anthracene (DMBA) and medroxyprogesterone acetate (MPA) induce breast tumors in tree shrews with a low frequency (<50%) and long latency (∼7-month), making these methods less than ideal. We induced mammary tumors in tree shrew (Tupaia belangeri chinensis) by injection of lentivirus expressing the PyMT oncogene into mammary ducts of 22 animals. Most tree shrews developed mammary tumors with a latency of about three weeks, and by 7 weeks all injected tree shrews had developed mammary tumors. Among these, papillary carcinoma is the predominant tumor type. One case showed lymph node and lung metastasis. Interestingly, the expression levels of phosphorylated AKT, ERK and STAT3 were elevated in 41-68% of PyMT-induced mammary tumors, but not all tumors. Finally, we observed that the growth of PyMT-induced tree shrew mammary tumors was significantly inhibited by Cisplatin and Epidoxorubicin. PyMT-induced tree shrew mammary tumor model may be suitable for further breast cancer research and drug development, due to its high efficiency and short latency. PMID:26296387

  19. "The Taming of the Shrew." A Play Packet To Accompany "Elementary, My Dear Shakespeare."

    ERIC Educational Resources Information Center

    Engen, Barbara; Campbell, Joy

    Intended for use by elementary school teachers as a supplement to the book, "Elementary, My Dear Shakespeare," or for use by itself to produce one Shakespeare play, this play packet contains ready-to-reproduce materials for the production of "The Taming of the Shrew." Materials include: staging suggestions for scenery, props, lighting, and

  20. Characterization of a MAVS ortholog from the Chinese tree shrew (Tupaia belangeri chinensis).

    PubMed

    Xu, Ling; Yu, Dandan; Peng, Li; Fan, Yu; Chen, Jiaqi; Zheng, Yong-Tang; Wang, Chen; Yao, Yong-Gang

    2015-09-01

    Human mitochondrial antiviral signaling protein (hMAVS, also known as IPS-1, VISA, or Cardif) is essential for antiviral innate immunity. The Chinese tree shrew (Tupaia belangeri chinenses), a close relative of primates, is emerging as a potential animal model for investigating viral infection. However, there is a lack of biological knowledge about the antiviral innate immunity of the tree shrew. In this study, we identified and characterized the function of the Chinese tree shrew MAVS gene (tMAVS). The cDNA of tMAVS was 2771 bp in length and encoded a polypeptide of 501 amino acids. Phylogenetic analyses based on the amino acid sequences revealed a closer affinity of tMAVS with those of primates. Quantitative real-time PCR analysis indicated that tMAVS mRNA was constitutively expressed in all seven tissues analyzed in this study. The tMAVS mRNA expression was rapidly and significantly increased after RNA virus infections. Ectopic-expression of tMAVS significantly potentiated the virus-triggered activation of IRF3, NF-?B and interferon-? (IFN-?), whereas knockdown of tMAVS displayed the opposite effect. Furthermore, tMAVS mutants lacking the caspase activation and recruitment (CARD) domains or the transmembrane (TM) domain were unable to induce IFN-?. Similar with hMAVS, mitochondrial localization of tMAVS was dependent on its domain. Collectively, this study revealed evolutionary conservation of the MAVS antiviral signaling pathway in the Chinese tree shrew. PMID:25931429

  1. Multilocus phylogeography and systematic revision of North American water shrews (genus: Sorex)

    USGS Publications Warehouse

    Hope, Andrew G.; Panter, Nicholas; Cook, Joseph A.; Talbot, Sandra L.; Nagorsen, David W.

    2014-01-01

    North American water shrews, which have traditionally included Sorex alaskanus, S. bendirii, and S. palustris, are widely distributed through Nearctic boreal forests and adapted for life in semiaquatic environments. Molecular mitochondrial signatures for these species have recorded an evolutionary history with variable levels of regional divergence, suggesting a strong role of Quaternary environmental change in speciation processes. We expanded molecular analyses, including more-comprehensive rangewide sampling of specimens representing North American water shrew taxa, except S. alaskanus, and sequencing of 4 independent loci from the nuclear and mitochondrial genomes. We investigated relative divergence of insular populations along the North Pacific Coast, and newly recognized diversity from southwestern montane locations, potentially representing refugial isolates. Congruent independent genealogies, lack of definitive evidence for contemporary gene flow, and high support from coalescent species trees indicated differentiation of 4 major geographic lineages over multiple glacial cycles of the late Quaternary, similar to a growing number of boreal taxa. Limited divergence of insular populations suggested colonization following the last glacial. Characterization of southwestern montane diversity will require further sampling but divergence over multiple loci is indicative of a relictual sky-island fauna. We have reviewed and revised North American water shrew taxonomy including the recognition of 3 species within what was previously known as S. palustris. The possibility of gene flow between most distantly related North American water shrew lineages coupled with unresolved early diversification of this group and other sibling species reflects a complex but potentially productive system for investigating speciation processes.

  2. Phenotypic flexibility in the energetic strategy of the greater white-toothed shrew, Crocidura russula.

    PubMed

    Oliveira, Flávio G; Tapisso, Joaquim T; Monarca, Rita I; Cerveira, Ana M; Mathias, Maria L

    2016-02-01

    The balance between energetic acquisition and expenditure depends on the amount of energy allocated to biological functions such as thermoregulation, growth, reproduction and behavior. Ambient temperature has a profound effect on this balance, with species inhabiting colder climates often needing to invest more energy in thermoregulation to maintain body temperature. This leads to local behavioral and physiological adaptations that increase energetic efficiency. In this study, we investigated the role of activity, behavior and thermogenic capacity in the ability of the greater white-toothed shrew, Crocidura russula, to cope with seasonal changes. Individuals were captured in the Sintra-Cascais Natural Park, a Mediterranean region, and separated into three experimental groups: a control group, acclimated to a 12L:12D photoperiod and temperature of 18-20°C; a winter group, acclimatized to natural winter fluctuations of light and temperature; and a summer group, acclimatized to natural summer fluctuations of light and temperature. No differences were found in resting metabolic rate and nonshivering thermogenesis between the three groups. However, winter shrews significantly reduced their activity, particularly at night, compared to the control and summer groups. Differences in torpor use were also found between groups, with winter shrews entering torpor more frequently and during shorter periods of time than summer and control shrews. Our results indicate C. russula from Sintra relies on the flexibility of energy saving mechanisms, namely daily activity level and torpor use, to cope with seasonal changes in a Mediterranean climate, rather than mechanisms involving body heat production. PMID:26857972

  3. Water balance and kidney function in the least shrew (Cryptotis parva).

    PubMed

    Goldstein, David L; Newland, Stacy

    2004-09-01

    We assessed renal function in least shrews (Cryptotis parva, body mass 4.7 g) within the context of overall water balance. The glomerular filtration rate (GFR) of shrews with unlimited food and water was 2.4 ml/h, about 60% of the rate predicted from body mass. Of this, about 3% (0.075 ml/h) was excreted as urine with an osmolality of 1944 mmol/kg, 5.5 times plasma osmolality. Shrews had a total water turnover (5 ml/day) two to three times higher than expected from allometry for a small mammal of this size. Water influx was partitioned among preformed water from food (65%), drinking (16%), and metabolic water (20%). Water efflux was divided among urine flow (35%), fecal water loss (estimated as 23%), and evaporation (by difference, 42%). Least shrews had a high water turnover rate and relatively high urine flow rate (UFR); this likely reflects a combination of factors, including high metabolism, active lifestyle, and wet diet. PMID:15471683

  4. Tree shrew as a new animal model for the study of lung cancer

    PubMed Central

    YE, LIANHUA; HE, MENG; HUANG, YUNCHAO; ZHAO, GUANGQIANG; LEI, YUJIE; ZHOU, YONGCHUN; CHEN, XIAOBO

    2016-01-01

    Animal models play a key role in identifying treatments for various types of cancer, including lung cancer. The aim of the present study was to develop a new animal model for lung cancer induction using tree shrews from the Yunnan region in China. Tree shrews are suitable for a full simulation of human disease because their structure, function and metabolism are adequately close to human. This animal may offer a new experimental animal model to be used in the study of lung cancer. In the present study, 80 healthy tree shrews were distributed in experimental and control groups. Animals in the experimental group received different concentrations of iodized oil suspension of 3-methylcholanthrene (3-MC) and diethylnitrosamine (DEN) while animals in the control groups received saline or lipiodol solvent via endotracheal instillation. In the 3rd, 5th, 7th, 9th and 11th weeks the body weights of the animals were measured and chest X-ray examinations were conducted. Pathological studies on the lung tissues were also performed and the pathological changes occurring in bronchial epithelium in all the groups were examined. Animals in the experimental group gradually lost their body weight. For tree shrews in the blank control and solvent control groups the survival rates were 100 and 80%, respectively while the survival rate for the experimental group was 0%. Results from the chest X-ray conducted on animals in the blank control and solvent control groups revealed no obvious abnormalities while in the experimental group high-density shadow spots within the perfusion sites were observed. Pathological studies performed on these high-density areas confirmed changes in the bronchial epithelium. In the experimental groups we also detected bronchial epithelial atypical hyperplasia, and apparent changes in carcinoma in situ. In conclusion, lung cancer was successfully induced in tree shrews by a one-time endotracheal introduction of iodized oil suspension of 3-MC and DEN.

  5. Genetic Diversity of Thottapalayam Virus, a Hantavirus Harbored by the Asian House Shrew (Suncus murinus) in Nepal

    PubMed Central

    Kang, Hae Ji; Kosoy, Michael Y.; Shrestha, Sanjaya K.; Shrestha, Mrigendra P.; Pavlin, Julie A.; Gibbons, Robert V.; Yanagihara, Richard

    2011-01-01

    Despite the recent discovery of genetically divergent hantaviruses in shrews of multiple species in widely separated geographic regions, data are unavailable about the genetic diversity and phylogeography of Thottapalayam virus (TPMV), a hantavirus originally isolated from an Asian house shrew (Suncus murinus) captured in southern India more than four decades ago. To bridge this knowledge gap, the S, M, and L segments of hantavirus RNA were amplified by reverse transcription polymerase chain reaction from archival lung tissues of Asian house shrews captured in Nepal from January to September 1996. Pair-wise alignment and comparison revealed approximately 80% nucleotide and > 94% amino acid sequence similarity to prototype TPMV. Phylogenetic analyses, generated by maximum likelihood and Bayesian methods, showed geographic-specific clustering of TPMV, similar to that observed for rodent- and soricid-borne hantaviruses. These findings confirm that the Asian house shrew is the natural reservoir of TPMV and suggest a long-standing virushost relationship. PMID:21896819

  6. Evolution of alanine:glyoxylate aminotransferase 1 peroxisomal and mitochondrial targeting. A survey of its subcellular distribution in the livers of various representatives of the classes Mammalia, Aves and Amphibia.

    PubMed

    Danpure, C J; Fryer, P; Jennings, P R; Allsop, J; Griffiths, S; Cunningham, A

    1994-08-01

    As part of a wider study on the molecular evolution of alanine:glyoxylate aminotransferase 1 (AGT1) intracellular compartmentalization, we have determined the subcellular distribution of immunoreactive AGT1, using postembedding protein A-gold immunoelectron microscopy, in the livers of various members of the classes Mammalia, Aves, and Amphibia. As far as organellar distribution is concerned, three categories could be distinguished. In members of the first category (type I), all, or nearly all, of the immunoreactive AGT1 was concentrated within the peroxisomes. In the second category (type II), AGT1 was found more evenly distributed in both peroxisomes and mitochondria. In the third category (type III), AGT1 was localized mainly within the mitochondria with much lower, but widely variable, amounts in the peroxisomes. Type I animals include the human, two great apes (gorilla, orangutan), two Old World monkeys (anubis baboon, Japanese macaque), a New World monkey (white-faced Saki monkey), a lago, morph (European rabbit), a bat (Seba's short-tailed fruit bat), two caviomorph rodents (guinea pig, orange-rumped agouti), and two Australian marsupials (koala, Bennett's wallaby). Type II animals include two New World monkeys (common marmoset, cotton-top tamarin), three prosimians (brown lemur, fat-tailed dwarf lemur, pygmy slow loris), five rodents (a hybrid crested porcupine, Colombian ground squirrel, laboratory rat, laboratory mouse, golden hamster), an American marsupial (grey short-tailed opossum), and a bird (raven). Type III animals include the large tree shrew, three insectivores (common Eurasian mole, European hedgehog, house shrew), four carnivores (domestic cat, ocelot, domestic dog, polecat ferret), and an amphibian (common frog). In addition to these categories, some animals (e.g. guinea pig, common frog) possessed significant amounts of cytosolic AGT1. Whereas the subcellular distribution of AGT1 in some orders (e.g. Insectivora and Carnivora) did not appear to vary markedly between the different members, in other orders (e.g. Primates, Rodentia and Marsupialia) it fluctuated widely between the different species. Phylogenetic analysis indicates that the subcellular distribution of AGT1 has changed radically on numerous occasions during the evolution of mammals. The new observations presented in this paper are compatible with our previous demonstration of a relationship between AGT1 subcellular distribution and either present or putative ancestral dietary habit, and our previous suggestion that the molecular evolution of the AGT gene has been markedly influenced by dietary selection pressure. PMID:7813517

  7. Isolation and identification of symbiotic bacteria from the skin, mouth, and rectum of wild and captive tree shrews.

    PubMed

    Li, Gui; Lai, Ren; Duan, Gang; Lyu, Long-Bao; Zhang, Zhi-Ye; Liu, Huang; Xiang, Xun

    2014-11-18

    Endosymbionts influence many aspects of their hosts' health conditions, including physiology, development, immunity, metabolism, etc. Tree shrews (Tupaia belangeri chinensis) have attracted increasing attention in modeling human diseases and therapeutic responses due to their close relationship with primates. To clarify the situation of symbiotic bacteria from their body surface, oral cavity, and anus, 12 wild and 12 the third generation of captive tree shrews were examined. Based on morphological and cultural characteristics, physiological and biochemical tests, as well as the 16S rDNA full sequence analysis, 12 bacteria strains were isolated and identified from the wild tree shrews: body surface: Bacillus subtilis (detection rate 42%), Pseudomonas aeruginosa (25%), Staphlococcus aureus (33%), S. Epidermidis (75%), Micrococcus luteus (25%), Kurthia gibsonii (17%); oral cavity: Neisseria mucosa (58%), Streptococcus pneumonia (17%); anus: Enterococcus faecalis (17%), Lactococus lactis (33%), Escherichia coli (92%), Salmonella typhosa (17%); whereas, four were indentified from the third generation captive tree shrews: body surface: S. epidermidis (75%); oral cavity: N.mucosa (67%); anus: L. lactis (33%), E. coli (100%). These results indicate that S. epidermidis, N. mucosa, L. lactis and E. coli were major bacteria in tree shrews, whereas, S. aureus, M. luteus, K. gibsonii, E. faecalis and S. typhosa were species-specific flora. This study facilitates the future use of tree shrews as a standard experimental animal and improves our understanding of the relationship between endosymbionts and their hosts. PMID:25465085

  8. Vocal development during postnatal growth and ear morphology in a shrew that generates seismic vibrations, Diplomesodon pulchellum.

    PubMed

    Zaytseva, Alexandra S; Volodin, Ilya A; Mason, Matthew J; Frey, Roland; Fritsch, Guido; Ilchenko, Olga G; Volodina, Elena V

    2015-09-01

    The ability of adult and subadult piebald shrews (Diplomesodon pulchellum) to produce 160Hz seismic waves is potentially reflected in their vocal ontogeny and ear morphology. In this study, the ontogeny of call variables and body traits was examined in 11 litters of piebald shrews, in two-day intervals from birth to 22 days (subadult), and ear structure was investigated in two specimens using micro-computed tomography (micro-CT). Across ages, the call fundamental frequency (f0) was stable in squeaks and clicks and increased steadily in screeches, representing an unusual, non-descending ontogenetic pathway of f0. The rate of the deep sinusoidal modulation (pulse rate) of screeches increased from 75Hz at 3-4 days to 138Hz at 21-22 days, probably relating to ontogenetic changes in contraction rates of the same muscles which are responsible for generating seismic vibrations. The ear reconstructions revealed that the morphologies of the middle and inner ears of the piebald shrew are very similar to those of the common shrew (Sorex araneus) and the lesser white-toothed shrew (Crocidura suaveolens), which are not known to produce seismic signals. These results suggest that piebald shrews use a mechanism other than hearing for perceiving seismic vibrations. PMID:26112702

  9. Metagenomic analysis of the shrew enteric virome reveals novel viruses related to human stool-associated viruses.

    PubMed

    Sasaki, Michihito; Orba, Yasuko; Ueno, Keisuke; Ishii, Akihiro; Moonga, Ladslav; Hang'ombe, Bernard M; Mweene, Aaron S; Ito, Kimihito; Sawa, Hirofumi

    2015-02-01

    Shrews are small insectivorous mammals that are distributed worldwide. Similar to rodents, shrews live on the ground and are commonly found near human residences. In this study, we investigated the enteric virome of wild shrews in the genus Crocidura using a sequence-independent viral metagenomics approach. A large portion of the shrew enteric virome was composed of insect viruses, whilst novel viruses including cyclovirus, picornavirus and picorna-like virus were also identified. Several cycloviruses, including variants of human cycloviruses detected in cerebrospinal fluid and stools, were detected in wild shrews at a high prevalence rate. The identified picornavirus was distantly related to human parechovirus, inferring the presence of a new genus in this family. The identified picorna-like viruses were characterized as different species of calhevirus 1, which was discovered previously in human stools. Complete or nearly complete genome sequences of these novel viruses were determined in this study and then were subjected to further genetic characterization. Our study provides an initial view of the diversity and distinctiveness of the shrew enteric virome and highlights unique novel viruses related to human stool-associated viruses. PMID:25381053

  10. Diverse interleukin-7 mRNA transcripts in Chinese tree shrew (Tupaia belangeri chinensis).

    PubMed

    Yu, Dandan; Xu, Ling; Liu, Xiao-Hong; Fan, Yu; L, Long-Bao; Yao, Yong-Gang

    2014-01-01

    Interleukin-7 (IL7) is a pleiotropic cytokine that is actively involved in the immune system. The Chinese tree shrew (Tupaia belangeri chinensis) has been proposed as an alternative experimental animal to primates in biomedical research. However, there is a lack of biological knowledge about the immune system of the tree shrew. In this study, we cloned the IL7 gene (tIL7) in the Chinese tree shrew and quantified the expression of mRNA transcripts in eight tissues (heart, liver, spleen, lung, kidney, intestine, skeletal muscle and brain) from 20 individuals. Eleven tIL7 mRNA transcripts were identified in different tissues. The canonical form (tIL7c) had a length of 1817 bp and encoded a predicted gene product with 177 amino acids. Phylogenetic analyses based on the amino acid sequences revealed a considerably large genetic difference between tree shrew and human. Quantification of mRNA expression of transcripts tIL7c, tIL7-sv1, tIL7-sv2 and tIL7-sv3 showed that these transcripts were expressed in all tissues, albeit the expression levels varied in different tissues. Transcripts tIL7c, tIL7-sv1, and tIL7-sv2 had the lowest expression in brain, and tIL7-sv3 had a dramatically high mRNA expression in skeletal muscle and heart. The mRNA expression levels of tIL7c and tIL7-sv1 were significantly increased upon ploy(I:C) stimulation in tree shrew primary renal cells. As with human full-length IL7, tIL7c, tIL7-sv1, tIL7-sv2 and tIL7-sv3 showed similar a subcellular localization pattern. Our results identified diverse tIL7 transcripts in the Chinese tree shrew, which may play a potential role in modulating IL7-regulated biological effects. PMID:24945249

  11. The Timing of the Shrew: Continuous Melatonin Treatment Maintains Youthful Rhythmic Activity in Aging Crocidura russula

    PubMed Central

    Magnanou, Elodie; Attia, Jol; Fons, Roger; Boeuf, Gilles; Falcon, Jack

    2009-01-01

    Background Laboratory conditions nullify the extrinsic factors that determine the wild expected lifespan and release the intrinsic or potential lifespan. Thus, wild animals reared in a laboratory often show an increased lifespan, and consequently an increased senescence phase. Senescence is associated with a broad suite of physiological changes, including a decreased responsiveness of the circadian system. The time-keeping hormone melatonin, an important chemical player in this system, is suspected to have an anti-aging role. The Greater White-toothed shrew Crocidura russula is an ideal study model to address questions related to aging and associated changes in biological functions: its lifespan is short and is substantially increased in captivity; daily and seasonal rhythms, while very marked the first year of life, are dramatically altered during the senescence process which starts during the second year. Here we report on an investigation of the effects of melatonin administration on locomotor activity of aging shrews. Methodology/Principal Findings 1) The diel fluctuations of melatonin levels in young, adult and aging shrews were quantified in the pineal gland and plasma. In both, a marked diel rhythm (low diurnal concentration; high nocturnal concentration) was present in young animals but then decreased in adults, and, as a result of a loss in the nocturnal production, was absent in old animals. 2) Daily locomotor activity rhythm was monitored in pre-senescent animals that had received either a subcutaneous melatonin implant, an empty implant or no implant at all. In non-implanted and sham-implanted shrews, the rhythm was well marked in adults. A marked degradation in both period and amplitude, however, started after the age of 1416 months. This pattern was considerably delayed in melatonin-implanted shrews who maintained the daily rhythm for significantly longer. Conclusions This is the first long term study (>500 days observation of the same individuals) that investigates the effects of continuous melatonin delivery. As such, it sheds new light on the putative anti-aging role of melatonin by demonstrating that continuous melatonin administration delays the onset of senescence. In addition, the shrew appears to be a promising mammalian model for elucidating the precise relationships between melatonin and aging. PMID:19526053

  12. Ultrastructural study of postnatal development of the tonsillar crypt epithelium of the musk shrew, Suncus murinus.

    PubMed

    Tohya, K; Kimura, M

    1992-09-01

    An ultrastructural study was made of the postnatal development of the tonsillar crypt epithelium in the musk shrew, Suncus murinus. On day 3 after birth, a particular kind of large lymphoid cell was first seen to move through the basement membrane into the epithelium. The next migration was that of lymphocytes, which passed through holes in the basement membrane. On days 5 to 7, the lymphocytes formed clusters, and pale epithelial cells of low electron density appeared. The cell clusters and pale epithelial cells fused on day 10. By day 14, these epithelial cells extended cytoplasmic projections to the surface of the epithelium, which had many heterophagic vacuoles and some microvilli-like structures. These findings suggest that the lymphoepithelial relationship is important for the organization of the immunological microenvironment in tonsillar crypt epithelium of the neonatal musk shrew. PMID:1416082

  13. Divergent ancestral lineages of newfound hantaviruses harbored by phylogenetically related crocidurine shrew species in Korea

    PubMed Central

    Arai, Satoru; Gu, Se Hun; Baek, Luck Ju; Tabara, Kenji; Bennett, Shannon; Oh, Hong-Shik; Takada, Nobuhiro; Kang, Hae Ji; Tanaka-Taya, Keiko; Morikawa, Shigeru; Okabe, Nobuhiko; Yanagihara, Richard; Song, Jin-Won

    2012-01-01

    Spurred by the recent isolation of a novel hantavirus, named Imjin virus (MJNV), from the Ussuri white-toothed shrew (Crocidura lasiura), targeted trapping was conducted for the phylogenetically related Asian lesser white-toothed shrew (Crocidura shantungensis). Pair-wise alignment and comparison of the S, M and L segments of a newfound hantavirus, designated Jeju virus (JJUV), indicated remarkably low nucleotide and amino acid sequence similarity with MJNV. Phylogenetic analyses, using maximum likelihood and Bayesian methods, showed divergent ancestral lineages for JJUV and MJNV, despite the close phylogenetic relationship of their reservoir soricid hosts. Also, no evidence of host switching was apparent in tanglegrams, generated by TreeMap 2.0?. PMID:22230701

  14. Binding sites of atrial natriuretic peptide in tree shrew adrenal gland

    SciTech Connect

    Fuchs, E.; Shigematsu, K.; Saavedra, J.M.

    1986-09-01

    Adrenal gland binding sites for atrial natriuretic peptide-(99-126) (ANP) were quantitated in tree shrew (Tupaia belangeri) by incubation of adrenal sections with (3-(/sup 125/I)-iodotyrosyl28) atrial natriuretic peptide-(99-126), followed by autoradiography with computerized microdensitometry. In the adrenal glands, there are three types of ANP binding sites. One is located in the zona glomerulosa (BMax 84 +/- 6 fmol/mg protein; Kd 122 +/- 9 pM); the second in the zona fasciculata and reticularis (BMax 29 +/- 2 fmol/mg protein; Kd 153 +/- 6 pM) and the third in the adrenal medulla (BMax 179 +/- 1 fmol/mg protein; Kd 70 +/- 2 pM). Besides the influence of ANP on the regulation of adrenocortical mineralcorticoid and glucocorticoid secretion our findings raise the possibility for a local site of action of atrial natriuretic peptide in the regulation of adrenomedullary catecholamines in the tree shrew, primates and man.

  15. High density lipoproteins and prevention of experimental atherosclerosis with special reference to tree shrews.

    PubMed

    She, M P; Xia, R Y; Ran, B F; Wong, Z L

    1990-01-01

    According to data obtained from epidemiological and experimental survey, serum HDL level is known to be correlated conversely with the incidence of atherosclerosis. Experimental data collected in this article explained part of its mechanism, which is described in four parts as follows: 1. The result of 3 successive experiments on experimental atherosclerosis in tree shrews (total of 96 animals available including 40 as the controls) showed that the serum HDL level had been kept persistantly to 69-88% of the total serum lipoproteins even after a high cholesterol intake for 32 weeks. The incidence of atheromatous lesions developed was only 0-9%, but the incidence of gall stone was very high, 48-84% by gross examination by the end of these experiments. 2. HDL are also capable of (1) promotion of monocyte migration activity; (2) enhancement of cholesterol clearance rate of aortic smooth muscle cells originally isolated from either rabbits or tree shrews; (3) inhibition of 20% of LDL degradation but with no inhibitory effect obtained on Ac-LDL degradation in the endothelial cells; (4) presence of specific binding sites for apo E free HDL on the surface of aortic smooth muscle cells from either rabbits or tree shrews which recognizes apo A1 as a ligand. 3. Data from 2 successive experiments in rabbits showed that HDL lipoproteins (mainly apo A1) possess an inhibitory effect on the development of atheromatous plaques, but not a very strong one. 4. The colesterol clearance effect of smooth muscle cells was markedly enhanced by apo A1/phospholipid liposomes (the apo A1 used was isolated from either rabbit's or tree shrew's serum) in vitro. PMID:2123379

  16. Histomorphology and immunohistochemistry of the lower esophageal sphincter of the least shrew (Cryptotis parva).

    PubMed

    Al-Tikriti, Mohammed S; Khamas, Wael; Chebolu, Seetha; Darmani, Nissar A

    2013-01-01

    The biochemical and histopathological changes in the lower esophageal sphincter (LES) in the pathogenesis of gastroesophageal reflux disease have gained interest. The least shrew is able to vomit in response to emetogens and provides a good model to study the histology of this phenomenon relative to the published reports in the commonly used but vomit-incompetent laboratory species. The LES is located at the junction of the esophagus and stomach. It typically closes at rest and opens in response to swallowing. Our findings demonstrate that the least shrew does not have a well-defined LES, lacks esophageal glands and has a mucosal valve-like projection from the terminal end of the esophagus before joining the gastric epithelium at the lesser curvature. In addition, the least shrew has thoracic and abdominal components prior to joining the gastric epithelium. The mucosal lining of the esophagus is folded, becoming clearly convoluted and forming a bucket-like structure at the level of the esophageocardiac junction (ECJ). No significant differences are to be found between the structure and thickness of the wall before and after the ECJ. Thus, the ECJ forming the LES is relatively less complex than those of other mammals including man. The distribution of enterochromaffin (EC) cells is confined to the lamina propria of the junction and is not associated with the cardiac glands, suggesting its functional involvement with the smooth muscle in and around the ECJ. In conclusion, the least shrew's anatomical sphincter appears ill-defined and is replaced by a less sturdy valve-like mucosal flap. PMID:24662490

  17. Histopathological changes in the liver of tree shrew (Tupaia belangeri chinensis) persistently infected with hepatitis B virus

    PubMed Central

    2013-01-01

    Background An animal model for HBV that more closely approximates the disease in humans is needed. The tree shrew (Tupaia belangeri) is closely related to primates and susceptible to HBV. We previously established that neonatal tree shrews can be persistently infected with HBV in vivo, and here present a six year follow-up histopathological study of these animals. Methods Group A consists of six tree shrews with persistent HBV infection, group B consists of three tree shrews with suspected persistent HBV infection, while group C consists of four tree shrews free of HBV infection. Serum and liver tissues samples were collected periodically from all animals. HBV antigen and HBV antibodies were detected by ELISA and/or TRFIA. HBV DNA in serum and in liver biopsies was measured by FQ-PCR. Liver biopsies were applied for general histopathologic observation and scoring, immunohistochemical detections of HBsAg and HBcAg, and ultrastructural observation with electron microscope technique. Results Hydropic, fatty and eosinophilic degeneration of hepatocytes, lymphocytic infiltration and hyperplasia of small bile ducts in the portal area were observed in group A. One animal infected with HBV for over six years showed multiple necrotic areas which had fused to form bridging necrosis and fibrosis, and megalocytosis. The hepatic histopathological scores of group A were higher than those of group B and C. The histopathological score correlated positively with the duration of infection. Conclusions Hepatic histopathological changes observed in chronically HBV-infected tree shrews are similar to those observed in HBV-infected humans. The tree shrew may represent a novel animal model for HBV infection. PMID:24220021

  18. Tree shrew lavatories: a novel nitrogen sequestration strategy in a tropical pitcher plant

    PubMed Central

    Clarke, Charles M.; Bauer, Ulrike; Lee, Ch'ien C.; Tuen, Andrew A.; Rembold, Katja; Moran, Jonathan A.

    2009-01-01

    Nepenthes pitcher plants are typically carnivorous, producing pitchers with varying combinations of epicuticular wax crystals, viscoelastic fluids and slippery peristomes to trap arthropod prey, especially ants. However, ant densities are low in tropical montane habitats, thereby limiting the potential benefits of the carnivorous syndrome. Nepenthes lowii, a montane species from Borneo, produces two types of pitchers that differ greatly in form and function. Pitchers produced by immature plants conform to the typical Nepenthes pattern, catching arthropod prey. However, pitchers produced by mature N. lowii plants lack the features associated with carnivory and are instead visited by tree shrews, which defaecate into them after feeding on exudates that accumulate on the pitcher lid. We tested the hypothesis that tree shrew faeces represent a significant nitrogen (N) source for N. lowii, finding that it accounts for between 57 and 100 per cent of foliar N in mature N. lowii plants. Thus, N. lowii employs a diversified N sequestration strategy, gaining access to a N source that is not available to sympatric congeners. The interaction between N. lowii and tree shrews appears to be a mutualism based on the exchange of food sources that are scarce in their montane habitat. PMID:19515656

  19. Daily metabolic patterns of short-tailed shrews (Blarina) in three natural seasonal temperature regimes

    SciTech Connect

    Randolph, J.C.

    1980-01-01

    An automatic, continuous-flow gas analysis system was used to determine daily metabolic patterns of individual short-tailed shrews (Blarina) in three natural seasonal temperature regimes in eastern Tennessee. Average daily metabolic rates (ADMR) were lowest in the summer (0.426 kcal g/sup -1/day/sup -1/), approximately doubled under winter conditions (0.810 kcal g/sup -1/day/sup -1/) but were the highest under fall conditions (1.110 kcal g/sup -1/day/sup -1/) possibly due to incomplete acclimatization of the shrews. The shape of the daily metabolic pattern for Blarina does not change seasonally; however, summer metabolic rates are the least variable and are lower than most values previously reported in the literature. Polynomial multiple regression analyses were conducted to examine the relative influence of body mass, ambient temperature, and time of day on metabolic rates; only ambient temperature was significant in predicting metabolic rates of this shrew. Average daily metabolic rates of Blarina observed under summer and winter conditions further substantiate the general predictive equations of metabolic rates formulated for small mammals by French et al. (1976). Comparisons of metabolic patterns of Blarina with those of Peromyscus leucopus observed under nearly identical conditions indicate similar rates with strong seasonal influences.

  20. Ultrastructure of the myocardium of the least shrew, Cryptotis parva Say.

    PubMed

    Forbes, M S; Mock, O B; Van Niel, E E

    1990-01-01

    The heart of the least shrew, Cryptotis parva Say, is an extremely active organ, capable of achieving rates of 800-1,200 beats/minute. The general features of myocardial cell ultrastructure in this insectivore are much like those of other small mammals; no single striking feature of fine structure is present to which the physiological properties of this heart might necessarily be attributed. Still there exist in these myocardial cells a number of atypical properties. These include 1) mitochondria having a wide variety of sizes and internal configurations 2) a pleiomorphic, highly ramified, small-diameter transverse-axial tubular system (TATS) 3) numerous "labyrinths," which are proliferated components of the TATS, and 4) myofibril-free regions, located both in juxtanuclear and other myoplasmic levels and populated by a concentration of TATS elements and fibrillar structures. Features (2) and (3) are also characteristic of another fast-beating heart, that of the mouse. The sinoatrial and atrioventricular nodal regions, as well as a Purkinje system, have been identified in the least shrew heart, along with sparsely distributed atrial cells whose myofibrils contain proliferated Z-band material. A feature frequently encountered in atrial working muscle cells is the occurrence of close appositions between gap junctions and tubules of sarcoplasmic reticulum; such appositions are also present in other regions of the shrew heart, as are complexes composed of gap junctions and mitochondria. PMID:2297084

  1. 1,3-dinitrobenzene toxicity in the least shrew, Cryptotis parva.

    PubMed

    Mock, Orin B; Casteel, Stan W; Darmani, Nissar A; Shaddy, James H; Besch-Williford, Cynthia; Towns, Lex C

    2005-10-01

    Shrews are abundant in most areas of toxic chemical contamination and bioaccumulate pollutants at much higher rates than sympatric rodent species. As a part of studies to provide information concerning the toxicity of 1,3-dinitrobenzene (DNB) in least shrews (Cryptotis parva), groups of 10 females and 10 males received DNB at 0 (control), 0.7, 2.9, 11.6, and 46.3 microl/L (equivalent mean daily dosage of 0, 0.26, 1.06, 4.26, and 17.0 mg/kg body wt in each sex) in their diet for 14 d. Leukocytosis present at the 0.26 mg/kg body weight/d dosage established the lowest-observed-adverse effect level (LOAEL). Adrenal enlargement was noted at the 1.06 mg/kg body weight/d level. Splenic enlargement and reductions in hematocrit and hemoglobin values occurred at the 4.26 mg/kg body weight/d treatment. Enlargements in the liver and heart and reductions in brown fat weight, granulocyte numbers, and alanine aminotransferase levels were present at high dose levels. Histopathologic examinations showed Kupffer's cell hemosiderosis and suggested testicular damage at the two highest tested doses but failed to confirm brain lesions. Least shrews do not follow standard scaling estimates for lifespan or metabolic rates. The LOAEL calculated from the standard terrestrial screening benchmark equation was higher than our findings, suggesting that these estimates must be viewed with caution. PMID:16268153

  2. [Some physiological and biochemical indicators of underyearling Laxman's shrews (Sorex cecutiens Laxmann) and even-toothed shrews (Sorex isodon Turov) under conditions of different population densities].

    PubMed

    Kiselev, S V; Lazutkin, A N; Yamborko, A V

    2013-01-01

    Based on the results of a study conducted in 2006-2010 in the Buyunda River basin (a feeder of the Kolyma River), the influence of the population density of common shrews (Sorex) on some of the physiological and biochemical parameters (glycogen and lipids in the liver, the relative weight of the spleen, the white and brown adipose tissue cellularity of bone and brain tissue) was investigated. The content of energy reserve substances was correlated with the number of animals (fat deposits had a negative correlation; the glycogen content in the liver had a direct correlation). For the rest of the physiological-biochemical parameters, no significant correlation with the population density was detected, although for the content of brown fat and cellularity of bone marrow tissue in Sorex isodon, as well as the relative weight of the spleen in both species of shrews, a trend was observed. We suggest that the identified physiological changes indicate irregular feeding of animals in years with higher population densities. PMID:24459854

  3. Establishment of the Tree Shrew as an Alcohol-Induced Fatty Liver Model for the Study of Alcoholic Liver Diseases

    PubMed Central

    Xing, Huijie; Jia, Kun; He, Jun; Shi, Changzheng; Fang, Meixia; Song, Linliang; Zhang, Pu; Zhao, Yue; Fu, Jiangnan; Li, Shoujun

    2015-01-01

    Currently, the pathogenesis of alcoholic liver diseases (ALDs) is not clear. As a result, there is no effective treatment for ALDs. One limitation is the lack of a suitable animal model for use in studying ALDs. The tree shrew is a lower primate animal, characterized by a high-alcohol diet. This work aimed to establish a fatty liver model using tree shrews and to assess the animals suitability for the study of ALDs. Tree shrews were treated with alcohol solutions (10% and 20%) for two weeks. Hemophysiology, blood alcohol concentrations (BACs), oxidative stress factors, alcohol metabolic enzymes and hepatic pathology were checked and assayed with an automatic biochemical analyzer, enzyme-linked immunosorbent assay (ELISA), western blot, hematoxylin-eosin (HE) staining and oil red O staining, and magnetic resonance imaging (MRI). Compared with the normal group, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), total cholesterol (TC), triglyceride (TG), reactive oxygen species (ROS), and malondialdehyde (MDA) were significantly enhanced in alcohol-treated tree shrews. However, the activity of reduced glutathione hormone (GSH) and superoxide dismutase (SOD) declined. Notable changes in alcohol dehydrogenase(ADH1), aldehyde dehydrogenase(ALDH2), CYP2E1, UDP-glucuronosyl transferase 1A1 (UGT1A1) and nuclear factor erythroid-related factor 2 (Nrf2) were observed. HE and oil red O staining showed that hepatocyte swelling, hydropic degeneration, and adipohepatic syndrome occurred in the tree shrews. Alcohol can induce fatty liver-like pathological changes and result in alterations in liver function, oxidative stress factors, alcohol metabolism enzymes and Nrf2. Therefore, the established fatty liver model of tree shrews induced by alcohol should be a promising tool for the study of ALDs. PMID:26030870

  4. Effect of PAHs on MFO induction in common shrews (Crocidura russula)

    SciTech Connect

    Bosveld, A.T.C.; Bie, P. de; Weggemans, J.; Murk, A.

    1995-12-31

    PAHs are widespread environmental contaminants. Despite the relatively high turnover rates for enzymatic breakdown, PAHs have been detected in tissues from species at various trophic levels. As a consequence they have the potential to be passed on to the higher levels of the foodchain. As a model for the primary carnivores in the terrestrial foodchain the common shrew (Crocidura russula) is studied in the laboratories. The authors investigated the effect of exposure to benzo[a]pyrene (BaP) on cytochrome P450 isoenzymes in relation to the effect of a known strong inducer of the MFO system i.e. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). The compounds were dissolved in oil and mixed with food. Shrews were exposed for a period of one week to BaP at concentrations equivalent to 10 or 100 mg/kg bodyweight per day (n = 3 for each dose group) and to TCDD at a concentration equivalent to 10 {micro}g/kg per day (n = 5). Controls received a diet with only the carier (oil) added. At termination of the experiment, hepatic CYP1A1 associated EROD activity was induced 20% in both the low and high dosed BaP group. In the TCDD exposed shrews EROD was induced up to 776% compared to the controls. Related MFO activities, including PROD, BROD, MROD and site specific testosterone hydroxylation are under investigation and the results will be presented. The relevance of MFO induction by PAHs and the use of these parameters as biomarkers for PAH exposure will be discussed.

  5. Demographic responses of shrews to removal of coarse woody debris in a managed pine forest.

    SciTech Connect

    McCay, Timothy, S.; Komoroski, Mark, J.

    2004-01-01

    McCay, T.S., and M.J. Komoroski. 2004. Demographic responses of shrews to removal of coarse woody debris in a managed pine forest. For. Ecol., and Mgt. 189:387-395. We trapped shrews at six 9.3 ha plots from which logs ý 10 cm diameter (coarse woody debris; CWD) had been manually removed and six control plots inmanaged loblolly pine (Pinus taeda) forests of the southeastern coastal plain, USA. Trapping was conducted seasonally between autumn 1997 and summer 2001. Capture rates of Cryptotis parva were lower at plots from which CWD was removed than at control plots (P ¡ 0ý011) and declined at all plots over the study period (P ¡ 0ý001). Capture rates of Blarina carolinensis (P ¡ 0ý129) and Sorex longirostris (P ¡ 0ý432) did not differ between removal and control plots, but declined over the study period (P ¡ 0ý001). Age distributions of B. carolinensis differed between removal and control plots (P ¡ 0ý048) with a smaller proportion of individuals in young age categories at removal plots. Sensitivity of Cryptotis to the removal of CWD may have been due to its sociality or low population density at the study area. A reduction in the abundance of young B. carolinensis after removal of CWD may reflect reduced reproduction and immigration of older individuals from outside the plot. Effect of removal of CWD on populations of these shrews was relatively weak compared to strong seasonal and multi-year variation in abundance. However, weak treatment effects may have been partly due to low ambient levels of CWD at control plots.

  6. Post-anesthesia vomiting: impact of isoflurane and morphine on ferrets and musk shrews.

    PubMed

    Horn, Charles C; Meyers, Kelly; Pak, Diana; Nagy, Allysa; Apfel, Christian C; Williams, Brian A

    2012-06-25

    Although partially controlled with antiemetic drugs, postoperative nausea and vomiting (PONV) continues to be a problem for many patients. Clinical research suggests that opioid analgesics and volatile anesthetics are the main triggers of PONV. The aim of this study was to develop an animal model for post-anesthesia vomiting for future studies to further determine mechanisms and preclinical drug efficacy. Ferrets (N=34) were initially used because they have served as a gold standard for emesis research. Ferrets were tested with several doses of morphine, inhaled isoflurane, and a positive control injection of cisplatin (a chemotherapy agent) to induce emesis. Musk shrews (a small animal model; N=36) were also tested for emesis with isoflurane exposure. A control injection of cisplatin produced emesis in ferrets (ip, 129.822.0 retches; 13.72.3 vomits; meanSEM). Morphine also produced a dose-response on emesis in ferrets, with maximal responses at 0.9 mg/kg (sc, 29.612.6 retches; 1.80.9, vomits). Isoflurane exposure (2-4% for 10 min to 6h exposure) failed to induce vomiting, was not associated with an increased frequency in emesis when combined with a low dose of morphine (0.1 mg/kg, sc), and failed to produce consistent effects on food and water intake. In contrast to ferrets, musk shrews were very sensitive to isoflurane-induced emesis (0.5 to 3%, 10 min exposure; up to 11.82.4 emetic episodes). Overall, these results indicate that ferrets will not be useful for delineating mechanisms responsible for isoflurane-induced emesis; however, musk shrews may prove to be a model for vomiting after inhalation of volatile agents. PMID:22504494

  7. Body temperature and behavior of tree shrews and flying squirrels in a thermal gradient.

    PubMed

    Refinetti, R

    1998-02-15

    The daily rhythms of body temperature, temperature selection, and locomotor activity of tree shrews and flying squirrels were studied in a thermal gradient. In accordance with previous observations in other mammalian species, the rhythm of temperature selection was found to be 180 degrees out of phase with the body temperature rhythm in both species. Comparison of the amplitude of the body temperature rhythm in the presence and absence of the ambient temperature gradient indicated that behavioral temperature selection reduces the amplitude of the body temperature rhythm. This provides support for the hypothesis that the homeostatic control of body temperature opposes-rather than facilitates-the circadian oscillation in body temperature. PMID:9523893

  8. Resting-Associated Vocalization Emitted by Captive Asian House Shrews (Suncus murinus): Acoustic Structure and Variability in an Unusual Mammalian Vocalization

    PubMed Central

    Schneiderová, Irena; Zouhar, Jan

    2014-01-01

    Shrews have rich vocal repertoires that include vocalizations within the human audible frequency range and ultrasonic vocalizations. Here, we recorded and analyzed in detail the acoustic structure of a vocalization with unclear functional significance that was spontaneously produced by 15 adult, captive Asian house shrews (Suncus murinus) while they were lying motionless and resting in their nests. This vocalization was usually emitted repeatedly in a long series with regular intervals. It showed some structural variability; however, the shrews most frequently emitted a tonal, low-frequency vocalization with minimal frequency modulation and a low, non-vocal click that was clearly noticeable at its beginning. There was no effect of sex, but the acoustic structure of the analyzed vocalizations differed significantly between individual shrews. The encoded individuality was low, but it cannot be excluded that this individuality would allow discrimination of family members, i.e., a male and female with their young, collectively resting in a common nest. The question remains whether the Asian house shrews indeed perceive the presence of their mates, parents or young resting in a common nest via the resting-associated vocalization and whether they use it to discriminate among their family members. Additional studies are needed to explain the possible functional significance of resting-associated vocalizations emitted by captive Asian house shrews. Our study highlights that the acoustic communication of shrews is a relatively understudied topic, particularly considering that they are highly vocal mammals. PMID:25390304

  9. On the relation between receptive field structure and stimulus selectivity in the tree shrew primary visual cortex.

    PubMed

    Veit, Julia; Bhattacharyya, Anwesha; Kretz, Robert; Rainer, Gregor

    2014-10-01

    There are notable differences in functional properties of primary visual cortex (V1) neurons among mammalian species, particularly those concerning the occurrence of simple and complex cells and the generation of orientation selectivity. Here, we present quantitative data on receptive field (RF) structure, response modulation, and orientation tuning for single neurons in V1 of the tree shrew, a close relative of primates. We find that spatial RF subfield segregation, a criterion for identifying simple cells, was exceedingly small in the tree shrew V1. In contrast, many neurons exhibited elevated F1/F0 modulation that is often used as a simple cell marker. This apparent discrepancy can be explained by the robust stimulus polarity preference in tree shrew V1, which inflates F1/F0 ratio values. RF structure mapped with sparse-noise-which is spatially restricted and emphasizes thalamo-cortical feed-forward inputs-appeared unrelated to orientation selectivity. However, RF structure mapped using the Hartley subspace stimulus-which covers a large area of the visual field and recruits considerable intracortical processing-did predict orientation preference. Our findings reveal a number of striking similarities in V1 functional organization between tree shrews and primates, emphasizing the important role of intracortical recurrent processing in shaping V1 response properties in these species. PMID:23696278

  10. Inference Based on Transitive Relation in Tree Shrews ("Tupaia belangeri") and Rats ("Rattus norvegicus") on a Spatial Discrimination Task

    ERIC Educational Resources Information Center

    Takahashi, Makoto; Ushitani, Tomokazu; Fujita, Kazuo

    2008-01-01

    Six tree shrews and 8 rats were tested for their ability to infer transitively in a spatial discrimination task. The apparatus was a semicircular radial-arm maze with 8 arms labeled A through H. In Experiment 1, the animals were first trained in sequence on 4 discriminations to enter 1 of the paired adjacent arms, AB, BC, CD, and DE, with right

  11. Inference Based on Transitive Relation in Tree Shrews ("Tupaia belangeri") and Rats ("Rattus norvegicus") on a Spatial Discrimination Task

    ERIC Educational Resources Information Center

    Takahashi, Makoto; Ushitani, Tomokazu; Fujita, Kazuo

    2008-01-01

    Six tree shrews and 8 rats were tested for their ability to infer transitively in a spatial discrimination task. The apparatus was a semicircular radial-arm maze with 8 arms labeled A through H. In Experiment 1, the animals were first trained in sequence on 4 discriminations to enter 1 of the paired adjacent arms, AB, BC, CD, and DE, with right…

  12. A Comparative Analysis of the Endocannabinoid System in the Retina of Mice, Tree Shrews, and Monkeys

    PubMed Central

    Bouskila, Joseph; Javadi, Pasha; Elkrief, Laurent; Casanova, Christian; Bouchard, Jean-François; Ptito, Maurice

    2016-01-01

    The endocannabinoid (eCB) system is widely expressed in various parts of the central nervous system, including the retina. The localization of the key eCB receptors, particularly CB1R and CB2R, has been recently reported in rodent and primate retinas with striking interspecies differences. Little is known about the distribution of the enzymes involved in the synthesis and degradation of these eCBs. We therefore examined the expression and localization of the main components of the eCB system in the retina of mice, tree shrews, and monkeys. We found that CB1R and FAAH distributions are well-preserved among these species. However, expression of NAPE-PLD is circumscribed to the photoreceptor layer only in monkeys. In contrast, CB2R expression is variable across these species; in mice, CB2R is found in retinal neurons but not in glial cells; in tree shrews, CB2R is expressed in Müller cell processes of the outer retina and in retinal neurons of the inner retina; in monkeys, CB2R is restricted to Müller cells. Finally, the expression patterns of MAGL and DAGLα are differently expressed across species. Overall, these results provide evidence that the eCB system is differently expressed in the retina of these mammals and suggest a distinctive role of eCBs in visual processing. PMID:26977322

  13. Angioarchitecture of the coeliac sympathetic ganglion complex in the common tree shrew (Tupaia glis)

    PubMed Central

    PROMWIKORN, WARAPORN; THONGPILA, SAKPORN; PRADIDARCHEEP, WISUIT; MINGSAKUL, THAWORN; CHUNHABUNDIT, PANJIT; SOMANA, REON

    1998-01-01

    The angioarchitecture of the coeliac sympathetic ganglion complex (CGC) of the common tree shrew (Tupaia glis) was studied by the vascular corrosion cast technique in conjunction with scanning electron microscopy. The CGC of the tree shrew was found to be a highly vascularised organ. It normally received arterial blood supply from branches of the inferior phrenic, superior suprarenal and inferior suprarenal arteries and of the abdominal aorta. In some animals, its blood supply was also derived from branches of the middle suprarenal arteries, coeliac artery, superior mesenteric artery and lumbar arteries. These arteries penetrated the ganglion at variable points and in slightly different patterns. They gave off peripheral branches to form a subcapsular capillary plexus while their main trunks traversed deeply into the inner part before branching into the densely packed intraganglionic capillary networks. The capillaries merged to form venules before draining into collecting veins at the peripheral region of the ganglion complex. Finally, the veins coursed to the dorsal aspect of the ganglion to drain into the renal and inferior phrenic veins and the inferior vena cava. The capillaries on the coeliac ganglion complex do not possess fenestrations. PMID:9877296

  14. Prevalence of zoonotic Bartonella species among rodents and shrews in Thailand.

    PubMed

    Pangjai, Decha; Maruyama, Soichi; Boonmar, Sumalee; Kabeya, Hidenori; Sato, Shingo; Nimsuphan, Burin; Petkanchanapong, Wimol; Wootta, Wattanapong; Wangroongsarb, Piyada; Boonyareth, Maskiet; Preedakoon, Poom; Saisongkorh, Watcharee; Sawanpanyalert, Pathom

    2014-03-01

    We investigated the prevalence of Bartonella species in 10 rodent and one shrew species in Thailand. From February 2008 to May 2010, a total of 375 small animals were captured in 9 provinces in Thailand. Bartonella strains were isolated from 57 rodents (54 from Rattus species and 3 from Bandicota indica) and one shrew (Suncus murinus) in 7 of the 9 provinces, and identified to the species level. Sequence analysis of the citrate synthase and RNA polymerase ? subunit genes identified the 58 isolates from each Bartonella-positive animal as B. tribocorum in 27 (46.6%) animals, B. rattimassiliensis in 17 (29.3%) animals, B. elizabethae in 10 (17.2%) animals and B. queenslandensis in 4 (6.9%) animals. R. norvegicus, R. rattus, and Suncus murinus carried B. elizabethae, which causes endocarditis in humans. The prevalence of Bartonella bacteremic animals by province was 42.9% of the animals collected in Phang Nga, 26.8% in Chiang Rai, 20.4% in Sa Kaeo, 16.7% in Nakhon Si Thammarat, 12.0% in Surat Thani, 9.1% in Mae Hong Son and Loei Provinces. These results indicate that Bartonella organisms are widely distributed in small mammals in Thailand and some animal species may serve as important reservoirs of zoonotic Bartonella species in the country. PMID:24393304

  15. Energy expenditure in Crocidurinae shrews (Insectivora): is metabolism a key component of the insular syndrome?

    PubMed

    Magnanou, Elodie; Fons, Roger; Blondel, Jacques; Morand, Serge

    2005-11-01

    A cascade of morphological, ecological, demographical and behavioural changes operates within island communities compared to mainland. We tested whether metabolic rates change on islands. Using a closed circuit respirometer, we investigated resting metabolic rate (RMR) of three species of Crocidurinae shrews: Suncus etruscus, Crocidura russula, and C. suaveolens. For the latter, we compared energy expenditure of mainland and island populations. Our measurements agree with those previously reported for others Crocidurinae: the interspecific comparison (ANCOVA) demonstrated an allometric relation between energy requirements and body mass. Energy expenditure also scaled with temperature. Island populations (Corsica and Porquerolles) of C. suaveolens differed in size from mainland (gigantism). A GLM showed a significant relationship between energy expenditure, temperature, body mass and locality. Mass specific RMR allometrically scales body mass, but total RMR does not significantly differ between mainland and island, although island shrews are giant. Our results are consistent with other studies: that demonstrated that the evolution of mammalian metabolism on islands is partially independent of body mass. In relation to the insular syndrome, we discuss how island selective forces (changes in resource availability, decrease in competition and predation pressures) can operate in size and physiological adjustments. PMID:16154371

  16. Ablation of Least Shrew Central Neurokinin NK1 Receptors Reduces GR73632-Induced Vomiting

    PubMed Central

    Ray, Andrew P; Chebolu, Seetha; Ramirez, Juan; Darmani, Nissar A

    2009-01-01

    The neurocircuitry mediating the emetic reflex is still incompletely understood, and a key question is the degree to which central and/or peripheral components contribute to the overall vomiting mechanism. Having previously found a significant peripheral component in neurokinin NK1-receptor mediated emesis, we undertook this study to examine the putative central component. Adult least shrews were injected intracerebroventricularly (i.c.v.) with saline or the blood-brain barrier impermeable toxin, Stable Substance P-saporin (SSP-SAP), which ablates cells expressing NK1 receptors. After three days, shrews were challenged intraperitoneally (i.p.) with the emetogenic NK1 agonist GR73632 at different doses and vomiting and scratching behaviors quantified. Ablation of NK1-bearing cells was verified immunohistochemically. Although SSP-SAP injection reduced emesis at 2.5 and 5 mg/kg GR73632 doses, no injections completely eliminated emesis. These data demonstrate that there is a major central nervous system component, and minor peripheral nervous system component, to tachykinin-mediated vomiting. Side effects of the current generation of antiemetics could potentially be reduced by improving bioavailability of the drugs in the more potent central nervous system compartment while reducing bioavailability in the less potent peripheral compartment. PMID:19485577

  17. [Cellular aspects of aging in the pineal gland of the shrew, Crocidurarussula].

    PubMed

    Dekar-Madoui, Aicha; Besseau, Laurence; Magnanou, Elodie; Fons, Roger; Ouali, Saliha; Bendjelloul, Mounira; Falcon, Jack

    2012-01-01

    The Greater White-toothed shrew Crocidura russula is short-lived species and the phase of senescence is greatly elongated in captivity. The loss of rhythmicity of biological functions that accompanies its aging is also well documented. C. russula is thus an excellent model to test the effects of aging on biological clocks. Melatonin is a key hormone in the synchronization of behaviors, metabolisms and physiological regulations with environmental factors. In the present work we want to know if the loss of rhythmicity and the reduced melatonin levels registered by the second year of life in this species could be associated to modified ultrastructural features of the pineal parenchyma, site of melatonin synthesis. Transmission electron microscopy (TEM) analysis of young (1-4 months) and old (25-28 months) shrew's pineals show that in older individuals, the parenchyma undergoes alterations affecting mainly nucleus, mitochondria and endoplasmic reticulum cisternae, with increased numbers of dense bodies and the formation of many concretions as well as a depletion of secretory products. These changes suggest a process of slowing pinealocytes metabolism which could explain the gradual reduction of melatonin levels registered during aging in C. russula. PMID:22226159

  18. Size evolution in Goodwin?s small-eared shrew, Cryptotis goodwini

    USGS Publications Warehouse

    Woodman, N.

    2005-01-01

    Fossils of Cryptotis goodwini from Honduras indicate that body sizes of modern individuals average at least 18% larger than among members of the late Pleistocene population of this species. Palynological and other paleoenvironmental studies provide evidence that the Neotropical montane environments that these shrews inhabit were cooler and drier in the late Pleistocene than at present and supported communities of plants without modern analog. Therefore, the most likely cause of this change in size ultimately was related to climatic change at the end of the Pleistocene?but to what specific factors did the species respond? I examined the possibilities that this species changed in size: to accommodate a change in temperature regime; to escape from predators; as a response to a change in intensity of interspecific competition; to take advantage of a newly abundant food resource. Based on evidence from studies of modern communities of shrews and niche partitioning, I hypothesized that size evolution in C. goodwini was directly related to changes in the community of soil and soil-surface invertebrates upon which the species depends, specifically an increase in the availability of earthworms (Annelida).

  19. A novel myxozoan parasite of terrestrial mammals: description of Soricimyxum minuti sp. n. (Myxosporea) in pygmy shrew Sorex minutus from Hungary.

    PubMed

    Szekely, Csaba; Cech, Gabor; Atkinson, Stephen D; Molnar, Kalman; Egyed, Laszlo; Gubanyi, Andras

    2015-01-01

    As part of a biodiversity study in northwestern Hungary, we conducted a parasitological survey of small mammals. In both common shrews (Sorex araneus Linnaeus) and pygmy shrews (Sorex minutus Linnaeus), we found myxospores of a species of Soricimyxum Prunescu, Prunescu, Pucek et Lom, 2007 (Myxosporea) and plasmodia in the bile ducts within the liver. Spores from both species of shrewswere morphologically and morphometrically indistinguishable, but differed in their SSU rRNA gene sequences by 3.3%. We identified spores and developmental stages from the common shrew as Soricimyxum fegati Prunescu, Prunescu, Pucek et Lom, 2007, based on morphometric data and DNA sequence similarity. Spores from the pygmy shrew were only 96.7% similar to S. fegati, hence we identified them as a novel myxosporean Soricimyxum minuti sp. n. This is only the second myxosporean parasite species described from mammals. PMID:26370293

  20. Dietary competition between the alien Asian Musk Shrew (Suncus murinus) and a re-introduced population of Telfair's Skink (Leiolopisma telfairii).

    PubMed

    Brown, D S; Burger, R; Cole, N; Vencatasamy, D; Clare, E L; Montazam, A; Symondson, W O C

    2014-08-01

    Re-introduction of rare species to parts of their historical range is becoming increasingly important as a conservation strategy. Telfair's Skinks (Leiolopisma telfairii), once widespread on Mauritius, were until recently found only on Round Island. There it is vulnerable to stochastic events, including the introduction of alien predators that may either prey upon it or compete for food resources. Consequently, skinks have been introduced to Ile aux Aigrettes, another small Mauritian island that has been cleared of rats. However, the island has been invaded by Asian Musk Shrews (Suncus murinus), a commensal species spread by man well beyond its natural Asian range. Our aim was to use next-generation sequencing to analyse the diets of the shrews and skinks to look for niche competition. DNA was extracted from skink faeces and from the stomach contents of shrews. Application of shrew- and skink-specific primers revealed no mutual predation. The DNA was then amplified using general invertebrate primers with tags to identify individual predators, and then sequenced by 454 pyrosequencing. 119 prey MOTUs (molecular taxonomic units) were isolated, although none could be identified to species. Seeding of cladograms with known sequences allowed higher taxonomic assignments in some cases. Although most MOTUs were not shared by shrews and skinks, Pianka's niche overlap test showed significant prey overlap, suggesting potentially strong competition where food resources are limited. These results suggest that removal of the shrews from the island should remain a priority. PMID:24033506

  1. Effect of land cover, habitat fragmentation and ant colonies on the distribution and abundance of shrews in southern California

    USGS Publications Warehouse

    Laakkonen, J.; Fisher, R.N.; Case, T.J.

    2001-01-01

    1. Because effects of habitat fragmentation and anthropogenic disturbance on native animals have been relatively little studied in arid areas and in insectivores, we investigated the roles of different land covers, habitat fragmentation and ant colonies on the distribution and abundance of shrews, Notiosorex crawfordi and Sorex ornatus, in southern California. 2. Notiosorex crawfordi was the numerically dominant species (trap-success rate 0.52) occurring in 21 of the 22 study sites in 85% of the 286 pitfall arrays used in this study. Sorex ornatus was captured in 14 of the sites, in 52% of the arrays with a total trap-success rate of 0.2. Neither of the species was found in one of the sites. 3. The population dynamics of the two shrew species were relatively synchronous during the 4-5-year study; the peak densities usually occurred during the spring. Precipitation had a significant positive effect, and maximum temperature a significant negative effect on the trap-success rate of S. ornatus. 4. Occurrence and abundance of shrews varied significantly between sites and years but the size of the landscape or the study site had no effect on the abundance of shrews. The amount of urban edge had no significant effect on the captures of shrews but increased edge allows invasion of the Argentine ants, which had a highly significant negative impact on the abundance of N. crawfordi. 5. At the trap array level, the percentage of coastal sage scrub flora had a significant positive, and the percentage of other flora had a significant negative effect on the abundance of N. crawfordi. The mean canopy height and the abundance of N. crawfordi had a significant positive effect on the occurrence of S. ornatus. 6. Our study suggests that the loss of native coastal sage scrub flora and increasing presence of Argentine ant colonies may significantly effect the distribution and abundance of N. crawfordi. The very low overall population densities of both shrew species in most study sites make both species susceptible to extinction in isolated habitat fragments due to environmental stochasticity, and anthropogenic disturbance.

  2. Mammals of South America, Volume 1, Marsupials, Xenarthrans, Shrews, and Bats

    USGS Publications Warehouse

    2007-01-01

    The vast terrain between Panama and Tierra del Fuego contains some of the world?s richest mammalian fauna, but until now it has lacked a comprehensive systematic reference to the identification, distribution, and taxonomy of its mammals. The first such book of its kind and the inaugural volume in a three-part series, Mammals of South America both summarizes existing information and encourages further research of the mammals indigenous to the region. Containing identification keys and brief descriptions of each order, family, and genus, the first volume of Mammals of South America covers marsupials, shrews, armadillos, sloths, anteaters, and bats. Species accounts include taxonomic descriptions, synonymies, keys to identification, distributions with maps and a gazetteer of marginal localities, lists of recognized subspecies, brief summaries of natural history information, and discussions of issues related to taxonomic interpretations. Highly anticipated and much needed, this book will be a landmark contribution to mammalogy, zoology, tropical biology, and conservation biology.

  3. Ultrastructure of geniculocortical synaptic connections in the tree shrew striate cortex.

    PubMed

    Familtsev, Dmitry; Quiggins, Ranida; P Masterson, Sean; Dang, Wenhao; Slusarczyk, Arkadiusz S; Petry, Heywood M; Bickford, Martha E

    2016-04-15

    To determine whether thalamocortical synaptic circuits differ across cortical areas, we examined the ultrastructure of geniculocortical terminals in the tree shrew striate cortex to compare directly the characteristics of these terminals with those of pulvinocortical terminals (examined previously in the temporal cortex of the same species; Chomsung et al. [] Cereb Cortex 20:997-1011). Tree shrews are considered to represent a prototype of early prosimian primates but are unique in that sublaminae of striate cortex layer IV respond preferentially to light onset (IVa) or offset (IVb). We examined geniculocortical inputs to these two sublayers labeled by tracer or virus injections or an antibody against the type 2 vesicular glutamate antibody (vGLUT2). We found that layer IV geniculocortical terminals, as well as their postsynaptic targets, were significantly larger than pulvinocortical terminals and their postsynaptic targets. In addition, we found that 9-10% of geniculocortical terminals in each sublamina contacted GABAergic interneurons, whereas pulvinocortical terminals were not found to contact any interneurons. Moreover, we found that the majority of geniculocortical terminals in both IVa and IVb contained dendritic protrusions, whereas pulvinocortical terminals do not contain these structures. Finally, we found that synaptopodin, a protein uniquely associated with the spine apparatus, and telencephalin (TLCN, or intercellular adhesion molecule type 5), a protein associated with maturation of dendritic spines, are largely excluded from geniculocortical recipient layers of the striate cortex. Together our results suggest major differences in the synaptic organization of thalamocortical pathways in striate and extrastriate areas. J. Comp. Neurol. 524:1292-1306, 2016. © 2015 Wiley Periodicals, Inc. PMID:26399201

  4. Solar radiation during rewarming from torpor in elephant shrews: supplementation or substitution of endogenous heat production?

    PubMed

    Thompson, Michelle L; Mzilikazi, Nomakwezi; Bennett, Nigel C; McKechnie, Andrew E

    2015-01-01

    Many small mammals bask in the sun during rewarming from heterothermy, but the implications of this behaviour for their energy balance remain little understood. Specifically, it remains unclear whether solar radiation supplements endogenous metabolic thermogenesis (i.e., rewarming occurs through the additive effects of internally-produced and external heat), or whether solar radiation reduces the energy required to rewarm by substituting (i.e, replacing) metabolic heat production. To address this question, we examined patterns of torpor and rewarming rates in eastern rock elephant shrews (Elephantulus myurus) housed in outdoor cages with access to either natural levels of solar radiation or levels that were experimentally reduced by means of shade cloth. We also tested whether acclimation to solar radiation availability was manifested via phenotypic flexibility in basal metabolic rate (BMR), non-shivering thermogenesis (NST) capacity and/or summit metabolism (Msum). Rewarming rates varied significantly among treatments, with elephant shrews experiencing natural solar radiation levels rewarming faster than conspecifics experiencing solar radiation levels equivalent to approximately 20% or 40% of natural levels. BMR differed significantly between individuals experiencing natural levels of solar radiation and conspecifics experiencing approximately 20% of natural levels, but no between-treatment difference was evident for NST capacity or Msum. The positive relationship between solar radiation availability and rewarming rate, together with the absence of acclimation in maximum non-shivering and total heat production capacities, suggests that under the conditions of this study solar radiation supplemented rather than substituted metabolic thermogenesis as a source of heat during rewarming from heterothermy. PMID:25853244

  5. Species Interactions during Diversification and Community Assembly in an Island Radiation of Shrews

    PubMed Central

    Esselstyn, Jacob A.; Maher, Sean P.; Brown, Rafe M.

    2011-01-01

    Background Closely related, ecologically similar species often have adjacent distributions, suggesting competitive exclusion may contribute to the structure of some natural communities. In systems such as island archipelagos, where speciation is often tightly associated with dispersal over oceanic barriers, competitive exclusion may prevent population establishment following inter-island dispersal and subsequent cladogenesis. Methodology/Principal Findings Using a combination of tools, we test the hypothesis that the distributions of shrew (Crocidura) species in the Philippines are the result of competitive exclusion preventing secondary invasion of occupied islands. We first compare ecological niche models between two widespread, allopatric species and find statistical support for their ecological similarity, implying that competition for habitat between these species is possible. We then examine dispersion patterns among sympatric species and find some signal for overdispersion of body size, but not for phylogenetic branch length. Finally, we simulate the process of inter-island colonization under a stochastic model of dispersal lacking ecological forces. Results are dependent on the geographic scope and colonization probability employed. However, some combinations suggest that the number of inter-island dispersal events necessary to populate the archipelago may be much higher than the minimum number of colonization events necessary to explain current estimates of species richness and phylogenetic relationships. If our model is appropriate, these results imply that alternative factors, such as competitive exclusion, may have influenced the process of inter-island colonization and subsequent cladogenesis. Conclusions/Significance We interpret the combined results as providing tenuous evidence that similarity in body size may prevent co-occurrence in Philippine shrews and that competitive exclusion among ecologically similar species, rather than an inability to disperse among islands, may have limited diversification in this group, and, possibly other clades endemic to island archipelagos. PMID:21760918

  6. Changing Material Properties of the Tree Shrew Sclera During Minus Lens Compensation and Recovery

    PubMed Central

    Grytz, Rafael; Siegwart, John T.

    2015-01-01

    Purpose. To estimate two collagen-specific material properties (crimp angle and elastic modulus of collagen fibrils) of the remodeling tree shrew sclera during monocular −5 diopter (D) lens wear and recovery. Methods. Tensile tests were performed on scleral strips obtained from juvenile tree shrews exposed to three different visual conditions: normal, monocular −5 D lens wear to induce myopia, and recovery. Collagen fibrils are crimped in the unloaded sclera and uncrimp as the tissue stiffens under load. Inverse numerical analyses were performed to estimate the (unloaded) crimp angle and elastic modulus of collagen fibrils using a microstructure-based constitutive model. Results. Compared with the control eye, the crimp angle was significantly higher in the treated eye after 2 days and remained significantly higher until 21 days of lens wear (P < 0.05). The difference between the crimp angle of the treated and control eye rapidly vanished during recovery in concert with the changes in axial elongation rate. A rapid and extensive increase in the elastic modulus was seen in both eyes after starting and stopping the lens wear. Conclusions. The estimated change in the crimp of scleral collagen fibrils is temporally associated with the change in axial elongation rate during myopia development and recovery. This finding suggests that axial elongation may be controlled by a remodeling mechanism that modulates the collagen fibril crimp. The observed binocular changes in scleral stiffness are not temporally associated with the axial elongation rate, indicating that scleral stiffening may not be causally related to myopia. PMID:25736788

  7. Solar Radiation during Rewarming from Torpor in Elephant Shrews: Supplementation or Substitution of Endogenous Heat Production?

    PubMed Central

    Thompson, Michelle L.; Mzilikazi, Nomakwezi; Bennett, Nigel C.; McKechnie, Andrew E.

    2015-01-01

    Many small mammals bask in the sun during rewarming from heterothermy, but the implications of this behaviour for their energy balance remain little understood. Specifically, it remains unclear whether solar radiation supplements endogenous metabolic thermogenesis (i.e., rewarming occurs through the additive effects of internally-produced and external heat), or whether solar radiation reduces the energy required to rewarm by substituting (i.e, replacing) metabolic heat production. To address this question, we examined patterns of torpor and rewarming rates in eastern rock elephant shrews (Elephantulus myurus) housed in outdoor cages with access to either natural levels of solar radiation or levels that were experimentally reduced by means of shade cloth. We also tested whether acclimation to solar radiation availability was manifested via phenotypic flexibility in basal metabolic rate (BMR), non-shivering thermogenesis (NST) capacity and/or summit metabolism (Msum). Rewarming rates varied significantly among treatments, with elephant shrews experiencing natural solar radiation levels rewarming faster than conspecifics experiencing solar radiation levels equivalent to approximately 20% or 40% of natural levels. BMR differed significantly between individuals experiencing natural levels of solar radiation and conspecifics experiencing approximately 20% of natural levels, but no between-treatment difference was evident for NST capacity or Msum. The positive relationship between solar radiation availability and rewarming rate, together with the absence of acclimation in maximum non-shivering and total heat production capacities, suggests that under the conditions of this study solar radiation supplemented rather than substituted metabolic thermogenesis as a source of heat during rewarming from heterothermy. PMID:25853244

  8. A fossil aardvark (Mammalia, Tubulidentata) from the lower Pliocene of Chad

    NASA Astrophysics Data System (ADS)

    Lehmann, Thomas; Vignaud, Patrick; Mackaye, Hassane Tasso; Brunet, Michel

    2004-12-01

    The Mission Paloanthropologique Franco-Tchadienne (MPFT) found a new species of Orycteropodidae (Mammalia, Tubulidentata) in the Koll fossiliferous sector, northern Chad. After Orycteropus abundulafus [Journal of Vertebrate Paleontology 20 (1) (2000) 205-209; Lehmann, T., Vignaud, P., Likius A., Brunet M., in press. A new Orycteropodidae (Mammalia, Tubulidentata) in the Mio-Pliocene of Northern Chad. Zool. J. Linnean Soc.], this specimen is the second complete skeleton of fossil aardvark found in the Djurab desert. It is the first complete representative of an Orycteropus species found in the Pliocene of Africa. In regard to the Miocene fossil aardvarks, this new taxon, Orycteropus djourabensis nov. sp., shows more affinities with the extant O. afer. The main differences are the larger teeth and the shorter hand in the fossil form. Kossom Bougoudi and Koll represent a chronological series that gives a unique opportunity for studying the evolution of the African Tubulidentata around the Mio-Pliocene boundary (5.5-4 My). The new species is distinct from the older Chadian Orycteropodid from KB and it embodies the taxonomic turnover that took place within the order Tubulidentata around this boundary in Africa. Moreover, this new species is the oldest known Orycteropus species that clearly belongs to the modern forms including the extant aardvark.

  9. Discovery of natural infection by Metagonimus hakubaensis Shimazu, 1999 (Trematoda: Heterophyidae) in Japanese water shrews (Chimarrogale platycephala) in Japan.

    PubMed

    Kudo, Noboru; Shigeta, Kai; Matsumoto, Koji; Oyamada, Takashi

    2014-11-01

    A total of 611 preserved adult Metagonimus spp. specimens recovered from 32 of 53 Japanese water shrews (Chimarrogale platycephala) that had previously been collected in Aomori Prefecture between June 1994 and August 1996, were examined in this study. Morphological examination revealed that 603 of these flukes were identical to M. hakubaensis Shimazu, 1999, and that the others were M. takahashii Suzuki, 1930 (n=4), M. otsurui Saito et Shimizu, 1968 (n=2), and M. miyatai Saito et al., 1997 (n=2). Each of the 32 Japanese water shrews infected with M. hakubaensis contained between 1 and 83 flukes. This is the first record of the natural final host for M. hakubaensis, since this fluke species was described. PMID:25131808

  10. Delineation of vagal emetic pathways: intragastric copper sulfate-induced emesis and viral tract tracing in musk shrews

    PubMed Central

    Meyers, Kelly; Lim, Audrey; Dye, Matthew; Pak, Diana; Rinaman, Linda; Yates, Bill J.

    2014-01-01

    Signals from the vestibular system, area postrema, and forebrain elicit nausea and vomiting, but gastrointestinal (GI) vagal afferent input arguably plays the most prominent role in defense against food poisoning. It is difficult to determine the contribution of GI vagal afferent input on emesis because various agents (e.g., chemotherapy) often act on multiple sensory pathways. Intragastric copper sulfate (CuSO4) potentially provides a specific vagal emetic stimulus, but its actions are not well defined in musk shrews (Suncus murinus), a primary small animal model used to study emesis. The aims of the current study were 1) to investigate the effects of subdiaphragmatic vagotomy on CuSO4-induced emesis and 2) to conduct preliminary transneuronal tracing of the GI-brain pathways in musk shrews. Vagotomy failed to inhibit the number of emetic episodes produced by optimal emetic doses of CuSO4 (60 and 120 mg/kg ig), but the effects of lower doses were dependent on an intact vagus (20 and 40 mg/kg). Vagotomy also failed to affect emesis produced by motion (1 Hz, 10 min) or nicotine administration (5 mg/kg sc). Anterograde transport of the H129 strain of herpes simplex virus-1 from the ventral stomach wall identified the following brain regions as receiving inputs from vagal afferents: the nucleus of the solitary tract, area postrema, and lateral parabrachial nucleus. These data indicate that the contribution of vagal pathways to intragastric CuSO4-induced emesis is dose dependent in musk shrews. Furthermore, the current neural tracing data suggest brain stem anatomical circuits that are activated by GI signaling in the musk shrew. PMID:24430885

  11. Dental and Mandibular Morphologies of Arboroharamiya (Haramiyida, Mammalia): A Comparison with Other Haramiyidans and Megaconus and Implications for Mammalian Evolution

    PubMed Central

    Meng, Jin; Bi, Shundong; Wang, Yuanqing; Zheng, Xiaoting; Wang, Xiaoli

    2014-01-01

    Background Two recent studies published in the same issue of Nature reached conflicting conclusions regarding the phylogeny of early mammals: One places the clade containing haramiyidans and multituberculates within the Mammalia and the other separates haramiyidans from multituberculates and places the former outside of the Mammalia. These two contrasting results require that the minimally oldest divergence time of the Mammalia was within the Late Triassic or the Middle Jurassic, respectively. Morphological descriptions of the species named in the two papers were brief, and no comparisons between the newly named species were possible. Principal Findings Here we present a detailed description of the dentary bone, teeth, occlusal and wear patterns of the haramiyidan Arboroharamiya and compare it with other haramiyidans and Megaconus. Using this new information, we suggest that tooth identifications and orientations of several previously described haramiyidan species are incorrect, and that previous interpretations of haramiyidan occlusal pattern are problematic. We propose that the published upper tooth orientation of Megaconus was problematic and question the number of upper molars, the length of dentition and mandible, and presence of the mandibular middle ear in Megaconus. Conclusions The additional morphological descriptions and comparisons presented here further support the view that Arboroharamiya, as a derived haramiyidan, shows similarity to multituberculates in tooth and mandible morphologies. Our comparison also suggests that Megaconus lacks many diagnostic features for the family Eleutherodontidae and that its close affinity with multituberculates cannot be ruled out. The detailed morphological data demonstrate that haramiyidans are more similar to multituberculates than to any other mammaliaforms. PMID:25494181

  12. Complete genome sequence and molecular phylogeny of a newfound hantavirus harbored by the Doucets musk shrew (Crocidura douceti) in Guinea

    PubMed Central

    Gu, Se Hun; Nicolas, Violaine; Lalis, Aude; Sathirapongsasuti, Nuankanya; Yanagihara, Richard

    2013-01-01

    Elucidation of the molecular phylogeny of shrew-borne hantaviruses in sub-Saharan Africa has been hampered by the lack of full-length viral genomes. In this report, we present the complete genome analysis of a newfound hantavirus, designated Bow virus, detected in ethanol-fixed intercostal muscle of a Doucets musk shrew (Crocidura douceti), captured in southwestern Guinea in February 2012. Full-length amino acid sequence comparison of the S-, M- and L-segment gene products revealed that Bow virus differed by 24.153.4%, 17.059.9% and 14.639.7%, respectively, from all other representative rodent-, shrew- and mole-borne hantaviruses. Phylogenetic analysis, using maximum-likelihood and Bayesian methods, under the GTR+I+? model of evolution, showed that Bow virus shared a common ancestry with Tanganya virus, a hantavirus detected in the Thereses shrew (Crocidura theresae) in Guinea. Whole genome analysis of many more hantaviruses from sub-Saharan Africa are needed to better clarify how the radiation of African shrews might have contributed to the phylogeography of hantaviruses. PMID:23994121

  13. "The diencephalon of Ptilocercus lowii (pen-tailed tree-shrew)".

    PubMed

    Simmons, R M

    1979-01-01

    The pen-tailed tree-shrew (Ptilocercus lowii) has been regarded by Le Gros Clark (1926), and Martin (1968) to possess more primitive morphological and to a certain extent, neuro-anatomical characteristics than the other tree-shrew species belonging to the sub-family Tupaiinae. Investigations have been carried out on the diencephalon of Ptilocercus lowii which has not been completely done by Le Gros Clark and other workers since 1926, to find out whether the diencephalon has actually undegone any phylogenetic changes that should be more advanced than those of the Insectivora or remain more primitive than that of the Tupaiinae. The diencephalic structure that show the most significant phylogenetic features which differe Ptilocerecus from Tupaia are observed in the anterior, dorsolateral and ventrolateral thalamic groups, and the geniculate bodies. The nucleus anteroventralis is, by comparison, much smaller and poorly differentiated from the nucleus anteromedialis. The nucleus anterodorsalis is also comparably large and does not reach the dorsal surface of the thalamus as it does in the primates. The midline nuclei do not show any significant differences, except the notably larger size of nucleus parataenialis in Ptilocercus. The nucleus mediodoralis is small and indifferentiated although it does show some incipient signs of cellular differentiation. The nucleus centralis lateralis is well developed; its inferior (ventral) part is larger than its superior part which is the better developed of the two parts in the tupaiids and primates. The nucleus centrum medianum appears to be very small and forms only a lateral extension of the nucleus parafascicularis. The ventrolateral thalamic group basically consists of nuclei ventrales anterior, lateralis and posterior without intermediate or transitional zones as found in Tupaia and Primates. The nucleus pretectalis is the largest and the best developed of all the elements of the posterior thalamic nuclear group. The lateral geniculate nucleus is not differentiated into laminae like that in Tupaia and Primates; it is merely a homogeneous structure that appears to be smaller in size that the pregeniculate and medial geniculate nuclei. The medial geniculate nucleus is large in proportional size of the whole thalamus and appears to be well differentiated cellularly into several small parts. No remarkable changes are noted in the epithalamus, subthalamus and hypothalamus. However, the nucleus ventromedialis appears to be the most outstanding structure in the infundibular region of the hypothalamus. The mammillary region is of a simpler construction in Ptilocercus than in Tupaia; it does not protrude from the ventral surface of the hypothalamus. In the light of these findings, the phyletic status of Ptilocercus in the family Tupaiidae is discussed. PMID:113455

  14. Sticky snack for sengis: The Cape rock elephant-shrew, Elephantulus edwardii (Macroscelidea), as a pollinator of the Pagoda lily, Whiteheadia bifolia (Hyacinthaceae)

    NASA Astrophysics Data System (ADS)

    Wester, Petra

    2010-12-01

    Following the recent discovery of rodent pollination in the Pagoda lily, Whiteheadia bifolia (Hyacinthaceae) in South Africa, now the Cape rock elephant-shrew, Elephantulus edwardii (Macroscelidea, Afrotheria) is reported as an additional pollinator. Elephant-shrews, live-trapped near W. bifolia plants, were released in two terraria, containing the plants. The animals licked nectar with their long and slender tongues while being dusted with pollen and touching the stigmas of the flowers with their long and flexible noses. The captured elephant-shrews had W. bifolia pollen in their faeces, likely as a result of grooming their fur as they visited the flowers without eating or destroying them. The animals mostly preferred nectar over other food. This is the first record of pollination and nectar consumption in the primarily insectivorous E. edwardii, contributing to the very sparse knowledge about the behaviour of this unique clade of African mammals, as well as pollination by small mammals.

  15. Sticky snack for sengis: the Cape rock elephant-shrew, Elephantulus edwardii (Macroscelidea), as a pollinator of the Pagoda lily, Whiteheadia bifolia (Hyacinthaceae).

    PubMed

    Wester, Petra

    2010-12-01

    Following the recent discovery of rodent pollination in the Pagoda lily, Whiteheadia bifolia (Hyacinthaceae) in South Africa, now the Cape rock elephant-shrew, Elephantulus edwardii (Macroscelidea, Afrotheria) is reported as an additional pollinator. Elephant-shrews, live-trapped near W. bifolia plants, were released in two terraria, containing the plants. The animals licked nectar with their long and slender tongues while being dusted with pollen and touching the stigmas of the flowers with their long and flexible noses. The captured elephant-shrews had W. bifolia pollen in their faeces, likely as a result of grooming their fur as they visited the flowers without eating or destroying them. The animals mostly preferred nectar over other food. This is the first record of pollination and nectar consumption in the primarily insectivorous E. edwardii, contributing to the very sparse knowledge about the behaviour of this unique clade of African mammals, as well as pollination by small mammals. PMID:21080154

  16. Affinities of `hyopsodontids' to elephant shrews and a Holarctic origin of Afrotheria

    NASA Astrophysics Data System (ADS)

    Zack, Shawn P.; Penkrot, Tonya A.; Bloch, Jonathan I.; Rose, Kenneth D.

    2005-03-01

    Macroscelideans (elephant shrews or sengis) are small-bodied (25-540g), cursorial (running) and saltatorial (jumping), insectivorous and omnivorous placental mammals represented by at least 15 extant African species classified in four genera. Macroscelidea is one of several morphologically diverse but predominantly African placental orders classified in the superorder Afrotheria by molecular phylogeneticists. The distribution of modern afrotheres, in combination with a basal position for Afrotheria within Placentalia and molecular divergence-time estimates, has been used to link placental diversification with the mid-Cretaceous separation of South America and Africa. Morphological phylogenetic analyses do not support Afrotheria and the fossil record favours a northern origin of Placentalia. Here we describe fossil postcrania that provide evidence for a close relationship between North American Palaeocene-Eocene apheliscine `hyopsodontid' `condylarths' (early ungulates or hoofed mammals) and extant Macroscelidea. Apheliscine postcranial morphology is consistent with a relationship to other ungulate-like afrotheres (Hyracoidea, Proboscidea) but does not provide support for a monophyletic Afrotheria. As the oldest record of an afrothere clade, identification of macroscelidean relatives in the North American Palaeocene argues against an African origin for Afrotheria, weakening support for linking placental diversification to the break-up of Gondwana.

  17. A climate for speciation: rapid spatial diversification within the Sorex cinereus complex of shrews

    USGS Publications Warehouse

    Hope, Andrew G.; Speer, Kelly A.; Demboski, John R.; Talbot, Sandra L.; Cook, Joseph A.

    2012-01-01

    The cyclic climate regime of the late Quaternary caused dramatic environmental change at high latitudes. Although these events may have been brief in periodicity from an evolutionary standpoint, multiple episodes of allopatry and divergence have been implicated in rapid radiations of a number of organisms. Shrews of the Sorex cinereus complex have long challenged taxonomists due to similar morphology and parapatric geographic ranges. Here, multi-locus phylogenetic and demographic assessments using a coalescent framework were combined to investigate spatiotemporal evolution of 13 nominal species with a widespread distribution throughout North America and across Beringia into Siberia. For these species, we first test a hypothesis of recent differentiation in response to Pleistocene climate versus more ancient divergence that would coincide with pre-Pleistocene perturbations. We then investigate the processes driving diversification over multiple continents. Our genetic analyses highlight novel diversity within these morphologically conserved mammals and clarify relationships between geographic distribution and evolutionary history. Demography within and among species indicates both regional stability and rapid expansion. Ancestral ecological differentiation coincident with early cladogenesis within the complex enabled alternating and repeated episodes of allopatry and expansion where successive glacial and interglacial phases each promoted divergence. The Sorex cinereus complex constitutes a valuable model for future comparative assessments of evolution in response to cyclic environmental change.

  18. Shrews, rats, and a polecat in "the pardoners tale": Chapter 3

    USGS Publications Warehouse

    Feinstein, Sandy; Woodman, Neal

    2012-01-01

    While historically existing animals and literary animal characters inform allegorical and metaphorical characterization in The Canterbury Tales, figurative usage does not erase recognition of the material animal. "The Pardoner's Tale," for one, challenges the terms of conventional animal metaphors by refocusing attention on common animals as common animals and common human creatures as something worse than vermin. Most attention has been paid to the larger animals-goat, hare, and horse-that constitute the physical portrait of Chaucer's Pardoner in the "General Prologue" and in the prologue to his tale.! Like these animals, rats and a polecat, together with rhetorical shrews, appear in this tale as well as in other literature, including bestiaries and natural histories. Equally to the purpose, these animals could be physically observed as constituents of both urban and rural landscapes in fourteenth-century England.2 In the Middle Ages, animals were part of the environment as well as part of the culture: they lived inside as well as outside the city gates, priory walls, and even domestic spaces; a rat in the street or the garden might not be any less welcome or uncommon than encountering someone's horses and goats nibbling vegetation or blocking a passage. Not being out of the ordinary, though, such animals could (and can) be overlooked or dismissed as common, too familiar to register. This chapter reveals why readers and listeners should pay close attention to the things they think they know and what they hear about what they think they know.

  19. A climate for speciation: rapid spatial diversification within the Sorex cinereus complex of shrews.

    PubMed

    Hope, Andrew G; Speer, Kelly A; Demboski, John R; Talbot, Sandra L; Cook, Joseph A

    2012-09-01

    The cyclic climate regime of the late Quaternary caused dramatic environmental change at high latitudes. Although these events may have been brief in periodicity from an evolutionary standpoint, multiple episodes of allopatry and divergence have been implicated in rapid radiations of a number of organisms. Shrews of the Sorex cinereus complex have long challenged taxonomists due to similar morphology and parapatric geographic ranges. Here, multi-locus phylogenetic and demographic assessments using a coalescent framework were combined to investigate spatiotemporal evolution of 13 nominal species with a widespread distribution throughout North America and across Beringia into Siberia. For these species, we first test a hypothesis of recent differentiation in response to Pleistocene climate versus more ancient divergence that would coincide with pre-Pleistocene perturbations. We then investigate the processes driving diversification over multiple continents. Our genetic analyses highlight novel diversity within these morphologically conserved mammals and clarify relationships between geographic distribution and evolutionary history. Demography within and among species indicates both regional stability and rapid expansion. Ancestral ecological differentiation coincident with early cladogenesis within the complex enabled alternating and repeated episodes of allopatry and expansion where successive glacial and interglacial phases each promoted divergence. The Sorex cinereus complex constitutes a valuable model for future comparative assessments of evolution in response to cyclic environmental change. PMID:22652055

  20. The antiemetic interaction of ?9-tetrahydrocannabinol when combined with tropisetron or dexamethasone in the least shrew

    PubMed Central

    Wang, Yaozhi; Ray, Andrew P.; McClanahan, Bryan A.; Darmani, Nissar A.

    2009-01-01

    5-HT3 receptor antagonists (e.g. tropisetron) combined with dexamethasone are effective for the acute phase of cisplatin (CIS)-induced emesis. This study determined the possible additive or synergistic antiemetic efficacy of ?9-THC when combined with tropisetron or dexamethasone (DEX). ?9-THC (0 10 mg/kg i.p.) was injected in combination with tropisetron (0 5 mg/kg i.p.) or dexamethasone (0 20 mg/kg i.p.) prior to CIS (20 mg/kg i.p.) in the least shrew, and the induced emesis was recorded for 60 minutes. CIS-induced vomiting was dose-dependently and significantly attenuated by individual administration of ?9-THC (5997% reductions) and tropisetron (79100% attenuation), but not dexamethasone (2640%), although a trend (p < .1) towards reduced vomiting frequency following DEX was noted. Low doses of ?9-THC (0.25 or 0.5 mg/kg) when combined with low doses of tropisetron (0.025, 0.1, or 0.25 mg/kg) were more efficacious in reducing emesis frequency than when given individually, but ?9-THC had no antiemetic interactions with DEX. However, no tested combination provided a significantly greater effect on the number of animals vomiting than their individually-administered counterparts. The modest interaction of ?9-THC with tropisetron suggests they activate overlapping antiemetic mechanisms, while the lack of interaction with dexamethasone needs further clarification. PMID:18727934

  1. Regulation of longitudinal esophageal motility in the house musk shrew (Suncus murinus).

    PubMed

    Shiina, Takahiko; Naitou, Kiyotada; Nakamori, Hiroyuki; Sakai, Hiroki; Shimizu, Yasutake

    2015-05-01

    Suncus murinus (house musk shrew; suncus) is a species of insectivore that has an ability to vomit. Although longitudinal movement of the esophagus would be related to the emetic response, regulatory mechanisms for the suncus esophageal motility are unclear. Therefore, the aim of the present study was to clarify components that regulate esophageal motility in the suncus. An isolated segment of the suncus esophagus was placed in an organ bath, and longitudinal mechanical responses were recorded using a force transducer. Electrical stimulation of the vagus trunk evoked a biphasic contractile response. The first phase of the contractile response was blocked by ?-bungarotoxin, a blocker of nicotinic acetylcholine receptors on striated muscle cells, whereas the second one was blocked by atropine, a blocker of muscarinic acetylcholine receptors on smooth muscle cells. Next, we investigated whether mast cells are involved in motor functions of the suncus esophagus. Application of a mast cell stimulator, compound 48/80, elicited contractile responses, which was resistant to tetrodotoxin. Exogenous application of serotonin and histamine induced contractile responses. The mast cell activation-mediated contraction was abolished by double desensitization by serotonin and histamine and pre-treatment with indomethacin, a cyclooxygenase inhibitor. The findings show that cholinergic and non-cholinergic transmitters induce longitudinal contraction in the suncus esophagus, which might contribute to esophageal shortening during emesis. Cholinergic transmitters are derived from vagal efferents, and non-cholinergic transmitters, which are thought to be serotonin, histamine and prostaglandins, are released from mast cells. PMID:25694232

  2. The Challenges of Resolving a Rapid, Recent Radiation: Empirical and Simulated Phylogenomics of Philippine Shrews.

    PubMed

    Giarla, Thomas C; Esselstyn, Jacob A

    2015-09-01

    Phylogenetic relationships in recent, rapid radiations can be difficult to resolve due to incomplete lineage sorting and reliance on genetic markers that evolve slowly relative to the rate of speciation. By incorporating hundreds to thousands of unlinked loci, phylogenomic analyses have the potential to mitigate these difficulties. Here, we attempt to resolve phylogenetic relationships among eight shrew species (genus Crocidura) from the Philippines, a phylogenetic problem that has proven intractable with small (< 10 loci) data sets. We sequenced hundreds of ultraconserved elements and whole mitochondrial genomes in these species and estimated phylogenies using concatenation, summary coalescent, and hierarchical coalescent methods. The concatenated approach recovered a maximally supported and fully resolved tree. In contrast, the coalescent-based approaches produced similar topologies, but each had several poorly supported nodes. Using simulations, we demonstrate that the concatenated tree could be positively misleading. Our simulations also show that the tree shape we tend to infer, which involves a series of short internal branches, is difficult to resolve, even if substitution models are known and multiple individuals per species are sampled. As such, the low support we obtained for backbone relationships in our coalescent-based inferences reflects a real and appropriate lack of certainty. Our results illuminate the challenges of estimating a bifurcating tree in a rapid and recent radiation, providing a rare empirical example of a nearly simultaneous series of speciation events in a terrestrial animal lineage as it spreads across an oceanic archipelago. PMID:25979143

  3. RADIATION ECOLOGY ISSUES ASSOCIATED WITH MURINE RODENTS AND SHREWS IN THE CHERNOBYL EXCLUSION ZONE

    SciTech Connect

    Farfan, E.; Jannik, T.

    2011-10-01

    This article describes major studies performed by the Chernobyl Center's International Radioecology Laboratory (Slavutich, Ukraine) on radioecology of murine rodents and shrews inhabiting the Chernobyl Exclusion Zone. The article addresses the long-term (1986-2005) and seasonal dynamics of radioactive contamination of animals, and reviews interspecies differences in radionuclide accumulations and factors affecting the radionuclide accumulations. It is shown that bioavailability of radionuclides in the 'soil-to-plant' chain and a trophic specialization of animals play key roles in determining their actual contamination levels. The total absorbed dose rates in small mammals significantly reduced during the years following the Chernobyl Nuclear Power Plant accident. In 1986, the absorbed dose rate reached 1.3-6.0 Gy hr{sup -1} in the central areas of the Chernobyl Exclusion Zone (the 'Red Forest'). In 1988 and 1990, the total absorbed dose rates were 1.3 and 0.42 Gy hr{sup -1}, respectively. In 1995, 2000, and 2005, according to the present study, the total absorbed dose rates rarely exceeded 0.00023, 0.00018, and 0.00015 Gy hr{sup -1}, respectively. Contributions of individual radiation sources into the total absorbed dose are described.

  4. Structure of the ovaries of the Nimba otter shrew, Micropotamogale lamottei, and the Madagascar hedgehog tenrec, Echinops telfairi.

    PubMed

    Enders, A C; Carter, A M; Knzle, H; Vogel, P

    2005-01-01

    The otter shrews are members of the subfamily Potamogalinae within the family Tenrecidae. No description of the ovaries of any member of this subfamily has been published previously. The lesser hedgehog tenrec, Echinops telfairi, is a member of the subfamily Tenrecinae of the same family and, although its ovaries have not been described, other members of this subfamily have been shown to have ovaries with non-antral follicles. Examination of these two species illustrated that non-antral follicles were characteristic of the ovaries of both species, as was clefting and lobulation of the ovaries. Juvenile otter shrews range from those with only small follicles in the cortex to those with 300- to 400-microm follicles similar to those seen in non-pregnant and pregnant adults. As in other species, most of the growth of the oocyte occurred when follicles had one to two layers of granulosa cells. When larger follicles became atretic in the Nimba otter shrew, hypertrophy of the theca interna produced nodules of glandular interstitial tissue. In the tenrec, the hypertrophying theca interna cells in most large follicles appeared to undergo degeneration. Both species had some follicular fluid in the intercellular spaces between the more peripheral granulosa cells. It is suggested that this fluid could aid in separation of the cumulus from the remaining granulosa at ovulation. The protruding follicles in lobules and absence of a tunica albuginea might also facilitate ovulation of non-antral follicles. Ovaries with a thin-absent tunica albuginea and follicles with small-absent antra are widespread within both the Eulipotyphla and in the Afrosoricida, suggesting that such features may represent a primitive condition in ovarian development. Lobulated and deeply crypted ovaries are found in both groups but are not as common in the Eulipotyphla making inclusion of this feature as primitive more speculative. PMID:16046864

  5. Invading and Expanding: Range Dynamics and Ecological Consequences of the Greater White-Toothed Shrew (Crocidura russula) Invasion in Ireland

    PubMed Central

    McDevitt, Allan D.; Montgomery, W. Ian; Tosh, David G.; Lusby, John; Reid, Neil; White, Thomas A.; McDevitt, C. Damien; O'Halloran, John; Searle, Jeremy B.; Yearsley, Jon M.

    2014-01-01

    Establishing how invasive species impact upon pre-existing species is a fundamental question in ecology and conservation biology. The greater white-toothed shrew (Crocidura russula) is an invasive species in Ireland that was first recorded in 2007 and which, according to initial data, may be limiting the abundance/distribution of the pygmy shrew (Sorex minutus), previously Ireland's only shrew species. Because of these concerns, we undertook an intensive live-trapping survey (and used other data from live-trapping, sightings and bird of prey pellets/nest inspections collected between 2006 and 2013) to model the distribution and expansion of C. russula in Ireland and its impacts on Ireland's small mammal community. The main distribution range of C. russula was found to be approximately 7,600 km2 in 2013, with established outlier populations suggesting that the species is dispersing with human assistance within the island. The species is expanding rapidly for a small mammal, with a radial expansion rate of 5.5 km/yr overall (20082013), and independent estimates from live-trapping in 20122013 showing rates of 2.414.1 km/yr, 0.57.1 km/yr and 05.6 km/yr depending on the landscape features present. S. minutus is negatively associated with C. russula. S. minutus is completely absent at sites where C. russula is established and is only present at sites at the edge of and beyond the invasion range of C. russula. The speed of this invasion and the homogenous nature of the Irish landscape may mean that S. minutus has not had sufficient time to adapt to the sudden appearance of C. russula. This may mean the continued decline/disappearance of S. minutus as C. russula spreads throughout the island. PMID:24955824

  6. Invading and expanding: range dynamics and ecological consequences of the greater white-toothed shrew (Crocidura russula) invasion in Ireland.

    PubMed

    McDevitt, Allan D; Montgomery, W Ian; Tosh, David G; Lusby, John; Reid, Neil; White, Thomas A; McDevitt, C Damien; O'Halloran, John; Searle, Jeremy B; Yearsley, Jon M

    2014-01-01

    Establishing how invasive species impact upon pre-existing species is a fundamental question in ecology and conservation biology. The greater white-toothed shrew (Crocidura russula) is an invasive species in Ireland that was first recorded in 2007 and which, according to initial data, may be limiting the abundance/distribution of the pygmy shrew (Sorex minutus), previously Ireland's only shrew species. Because of these concerns, we undertook an intensive live-trapping survey (and used other data from live-trapping, sightings and bird of prey pellets/nest inspections collected between 2006 and 2013) to model the distribution and expansion of C. russula in Ireland and its impacts on Ireland's small mammal community. The main distribution range of C. russula was found to be approximately 7,600 km2 in 2013, with established outlier populations suggesting that the species is dispersing with human assistance within the island. The species is expanding rapidly for a small mammal, with a radial expansion rate of 5.5 km/yr overall (2008-2013), and independent estimates from live-trapping in 2012-2013 showing rates of 2.4-14.1 km/yr, 0.5-7.1 km/yr and 0-5.6 km/yr depending on the landscape features present. S. minutus is negatively associated with C. russula. S. minutus is completely absent at sites where C. russula is established and is only present at sites at the edge of and beyond the invasion range of C. russula. The speed of this invasion and the homogenous nature of the Irish landscape may mean that S. minutus has not had sufficient time to adapt to the sudden appearance of C. russula. This may mean the continued decline/disappearance of S. minutus as C. russula spreads throughout the island. PMID:24955824

  7. ON and OFF subfield organization of layer 2/3 neurons in tree shrew visual cortex.

    PubMed

    Lee, Kuo-Sheng; Huang, Xiaoying; Fitzpatrick, David

    2015-09-01

    In vivo 2-photon imaging of calcium sensors in visual cortex has provided a host of new insights into the fine scale columnar mapping of response properties like orientation, direction, and visual space. Extracellular recording in carnivores have shown a columnar segregation of ON- and OFF-center geniculate inputs in layer 4, which could provide the basis for the generation of orientation selectivity. However, the spatial arrangement of ON and OFF in layer 2/3 has not been addressed. In this study we used 2-photon imaging of GCamP6s calcium fluorescent signals to map the receptive fields of thousands of neurons in layer 2/3 of tree shrew visual cortex with reverse correlation using sparse noise. We found a diverse array of receptive field properties in layer 2/3 including neurons with classic simple, complex and single sign receptive fields (either ON or OFF). The ON and OFF subfields in layer 2/3 were found to exhibit topologically distinct relationships with the maps of visual space and orientation preference. In most cases, the centers of OFF subfields for neurons in a given region of cortex were confined to a compact region of visual space and displayed a smooth retinotopic progression, while the centers of the ON subfields were distributed over a wider region of visual space and displayed less retinotopic precision. Consistent with the arrangement of ON and OFF subfields of simple cells in other species, the angle of displacement in visual space of the ON and OFF subfields for individual neurons could be used to predict the organization of the orientation map. Taken together, these results suggest that the differential arrangement of ON and OFF subfield centers by cortical circuits meets the conjoint constraints of mapping both visuotopy and orientation in a single population of neurons and in a fashion that preserves continuity for both stimulus features. Meeting abstract presented at VSS 2015. PMID:26326678

  8. House musk shrew (Suncus murinus, order: Insectivora) as a new model animal for motilin study.

    PubMed

    Tsutsui, Chihiro; Kajihara, Kie; Yanaka, Takatsugu; Sakata, Ichiro; Itoh, Zen; Oda, Sen-ichi; Sakai, Takafumi

    2009-02-01

    Although many studies have demonstrated the action of motilin on migrating motor complex by using human subjects and relatively large animals, the precise physiological mechanisms of motilin remain obscure. One reason for the lack of progress in this research field is that large animals are generally not suitable for molecular-level study. To overcome this problem, in this study, we focused on the house musk shrew (Suncus murinus, order: Insectivora, suncus named as laboratory strain) as a small model animal, and we present here the results of motilin gene cloning and its availability for motilin study. The motilin gene has a high homology sequence with that of other mammals, including humans. Suncus motilin is predicted to exist as a 117-residue prepropeptide that undergoes proteolytic cleavage to form a 22-amino-acid mature peptide. The results of RT-PCR showed that motilin mRNA is highly expressed in the upper small intestine, and low levels of expression were found in many tissues. Morphological analysis revealed that suncus motilin-producing cells were present in the upper small intestinal mucosal layer but not in the myenteric plexus. Administration of suncus motilin to prepared muscle strips of rabbit duodenum showed almost the same contractile effect as that of human motilin. Moreover, suncus stomach preparations clearly responded to suncus or human motilin stimulation. To our knowledge, this is the first report that physiological active motilin was determined in small laboratory animals, and the results of this study suggest that suncus is a suitable model animal for studying the motilin-ghrelin family. PMID:18996160

  9. Neural regulation of esophageal striated muscle in the house musk shrew (Suncus murinus).

    PubMed

    Shiina, Takahiko; Shima, Takeshi; Suzuki, Yuji; Wrl, Jrgen; Shimizu, Yasutake

    2012-05-21

    In the present study, we characterized the neural regulation of esophageal striated muscle in Suncus murinus (a house musk shrew; "suncus" used as a laboratory name), which was compared with that in the rat. The tunica muscularis consists of striated muscle in the suncus esophagus. An isolated segment of the suncus esophagus was placed in an organ bath and the contractile responses were recorded using a force transducer. Electrical stimulations to vagus nerves induced contractile responses in the esophageal segment. Treatment with ?-bungarotoxin, a blocker of nicotinic acetylcholine receptors, blocked the vagally mediated contractions of the suncus esophagus. D-tubocurarine and succinylcholine, typical antagonists of nicotinic acetylcholine receptors, also inhibited the suncus esophageal contractions, while higher concentrations of the agents were required rather than concentrations for producing an equivalent block in the rat. We used capsaicin, a stimulator of small-caliber afferent neurons, for activating the peripheral neural network. The reagent inhibited the vagally mediated twitch contractions of striated muscle in the suncus esophagus, which was reversed by pretreatment with a nitric oxide synthase inhibitor, N(G)-nitro-L-arginine methyl ester. Application of a nitric oxide donor, diethylamine NONOate diethylammonium salt, mimicked capsaicin-induced inhibition. The results suggest that motility of the suncus esophagus, which consists of striated muscles, is regulated by vagal cholinergic neurons. The local neural network including capsaicin-sensitive neurons and intrinsic nitrergic neurons can modify the vagally mediated motility in the suncus esophagus. In addition, nicotinic acetylcholine receptors of the suncus esophagus might be pharmacologically distinct from those of rodent esophagi. PMID:22285704

  10. Phenotypic Variation across Chromosomal Hybrid Zones of the Common Shrew (Sorex araneus) Indicates Reduced Gene Flow

    PubMed Central

    Polly, P. David; Polyakov, Andrei V.; Ilyashenko, Vadim B.; Onischenko, Sergei S.; White, Thomas A.; Shchipanov, Nikolay A.; Bulatova, Nina S.; Pavlova, Svetlana V.; Borodin, Pavel M.; Searle, Jeremy B.

    2013-01-01

    Sorex araneus, the Common shrew, is a species with more than 70 karyotypic races, many of which form parapatric hybrid zones, making it a model for studying chromosomal speciation. Hybrids between races have reduced fitness, but microsatellite markers have demonstrated considerable gene flow between them, calling into question whether the chromosomal barriers actually do contribute to genetic divergence. We studied phenotypic clines across two hybrid zones with especially complex heterozygotes. Hybrids between the Novosibirsk and Tomsk races produce chains of nine and three chromosomes at meiosis, and hybrids between the Moscow and Seliger races produce chains of eleven. Our goal was to determine whether phenotypes show evidence of reduced gene flow at hybrid zones. We used maximum likelihood to fit tanh cline models to geometric shape data and found that phenotypic clines in skulls and mandibles across these zones had similar centers and widths as chromosomal clines. The amount of phenotypic differentiation across the zones is greater than expected if it were dissipating due to unrestricted gene flow given the amount of time since contact, but it is less than expected to have accumulated from drift during allopatric separation in glacial refugia. Only if heritability is very low, Ne very high, and the time spent in allopatry very short, will the differences we observe be large enough to match the expectation of drift. Our results therefore suggest that phenotypic differentiation has been lost through gene flow since post-glacial secondary contact, but not as quickly as would be expected if there was free gene flow across the hybrid zones. The chromosomal tension zones are confirmed to be partial barriers that prevent differentiated races from becoming phenotypically homogenous. PMID:23874420

  11. Pranlukast prevents cysteinyl leukotriene-induced emesis in the least shrew (Cryptotis parva)

    PubMed Central

    Chebolu, Seetha; Wang, Yaozhi; Ray, Andrew P.; Darmani, Nissar A.

    2009-01-01

    Many chemotherapeutic agents activate multiple signaling systems, including potentially emetogenic arachidonic acid metabolites. Of these messengers, the emetic role of the leukotriene family has been neglected. The aims of this study were to test the emetic potential of key leukotrienes (LTA4, LTB4, LTF4, and the cysteinyl leukotrienes LTC4, LTD4 and LTE4), and to investigate whether the leukotriene CysLT1 receptor antagonist pranlukast or mixed leukotriene CysLT1/2 receptor antagonist Bay u9773 can prevent the LTC4 induced emesis. Least shrews were injected with varying doses of one of the six tested leukotrienes and vomiting parameters measured for 30 minutes. LTC4 and LTD4 were most efficacious, and significantly increased both the frequency and percentage of animals vomiting at doses from 0.1 and 0.05 mg/kg, respectively. The other tested leukotrienes were either weakly emetic or ineffective at doses up to 4 mg/kg. The relative emetogenic activities of the cysteinyl leukotrienes (LTC4=LTD4>LTE4) suggest leukotriene CysLT2 receptors have a key role in emesis. However, pranlukast dose-dependently, and at 10 mg/kg completely, blocked LTC4-induced vomiting, implicating a leukotriene CysLT1 receptor-mediated emetic effect. Bay u9773 dose-dependently reduced the percentage of animals vomiting, but did not significantly reduce vomiting frequency. Fos immunoreactivity, measured subsequent to LTC4-induced vomiting to define its putative anatomical substrates, was significantly increased in the enteric nervous system and medullary dorsal vagal complex following LTC4 (P < 0.05) versus vehicle injections. This study is the first to show that some leukotrienes induce emesis, possibly involving both central and peripheral leukotriene CysLT1 and/or leukotriene CysLT2 receptors. PMID:19941848

  12. Pranlukast prevents cysteinyl leukotriene-induced emesis in the least shrew (Cryptotis parva).

    PubMed

    Chebolu, Seetha; Wang, Yaozhi; Ray, Andrew P; Darmani, Nissar A

    2010-02-25

    Many chemotherapeutic agents activate multiple signaling systems, including potentially emetogenic arachidonic acid metabolites. Of these messengers, the emetic role of the leukotriene family has been neglected. The aims of this study were to test the emetic potential of key leukotrienes (LTA(4), LTB(4), LTF(4), and the cysteinyl leukotrienes LTC(4), LTD(4) and LTE(4)), and to investigate whether the leukotriene CysLT(1) receptor antagonist pranlukast or mixed leukotriene CysLT(1/2) receptor antagonist Bay u9773 can prevent the LTC(4)-induced emesis. Least shrews were injected with varying doses of one of the six tested leukotrienes and vomiting parameters were measured for 30min. LTC(4) and LTD(4) were most efficacious, and significantly increased both the frequency and percentage of animals vomiting at doses from 0.1 and 0.05mg/kg, respectively. The other tested leukotrienes were either weakly emetic or ineffective at doses up to 4mg/kg. The relative emetogenic activities of the cysteinyl leukotrienes (LTC(4)=LTD(4)>LTE(4)) suggest that leukotriene CysLT(2) receptors have a key role in emesis. However, pranlukast dose-dependently, and at 10mg/kg completely, blocked LTC(4)-induced vomiting, implicating a leukotriene CysLT(1) receptor-mediated emetic effect. Bay u9773 dose-dependently reduced the percentage of animals vomiting, but did not significantly reduce vomiting frequency. Fos immunoreactivity, measured subsequent to LTC(4)-induced vomiting to define its putative anatomical substrates, was significantly increased in the enteric nervous system and medullary dorsal vagal complex following LTC(4) (P<0.05) versus vehicle injections. This study is the first to show that some leukotrienes induce emesis, possibly involving both central and peripheral leukotriene CysLT(1) and/or leukotriene CysLT(2) receptors. PMID:19941848

  13. Overview of the Cestode fauna of European shrews of the genus Sorex with an exploration of historical processes in post-glacial Europe

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cestode fauna in shrews of the genus Sorex from the European region consists of seventeen species. Twelve cestode species have broad Palearctic distributions, three belong to the Western-Asian–European faunistic complex, and only two are endemic to the European zone. Postglacial expansion into ...

  14. The position of tree shrews in the mammalian tree: Comparing multi-gene analyses with phylogenomic results leaves monophyly of Euarchonta doubtful.

    PubMed

    Zhou, Xuming; Sun, Fengming; Xu, Shixia; Yang, Guang; Li, Ming

    2015-03-01

    The well-accepted Euarchonta grandorder is a pruned version of Archonta nested within the Euarchontoglires (or Supraprimates) clade. At present, it includes tree shrews (Scandentia), flying lemurs (Dermoptera) and primates (Primates). Here, a phylogenomic dataset containing 1912 exons from 22 representative mammals was compiled to investigate the phylogenetic relationships within this group. Phylogenetic analyses and hypothesis testing suggested that tree shrews can be classified as a sister group to Primates or to Glires or even as a basal clade within Euarchontoglires. Further analyses of both modified and original previously published datasets found that the phylogenetic position of tree shrews is unstable. We also found that two of three exonic indels reported as synapomorphies of Euarchonta in a previous study do not unambiguously support the monophyly of such a clade. Therefore, the monophyly of both Euarchonta and Sundatheria (Dermoptera + Scandentia) are suspect. Molecular dating and divergence rate analyses suggested that the ancestor of Euarchontoglires experienced a rapid divergence, which may cause the unresolved position of tree shrews even using the whole genomic data. PMID:25311886

  15. Cholesterol induces lipoprotein lipase expression in a tree shrew (Tupaia belangeri chinensis) model of non-alcoholic fatty liver disease

    PubMed Central

    Zhang, Linqiang; Zhang, Zhiguo; Li, Yunhai; Liao, Shasha; Wu, Xiaoyun; Chang, Qing; Liang, Bin

    2015-01-01

    Animal models are indispensible to investigate the pathogenesis and treatments of non-alcoholic fatty liver diseases (NAFLD). Altered cholesterol metabolism has been implicated into the pathogenesis of NAFLD. Here, using high fat, cholesterol and cholate diet (HFHC), we generated a novel tree shrew (Tupaia belangeri chinensis) model of NAFLD, which displayed dyslipidemia with increased levels of plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST), total cholesterol (TC), low density lipoprotein-cholesterol (LDL-c) and high density lipoprotein-cholesterol (HDL-c), but decreased level of triglycerides (TG). Liver histopathology and genes expression indicated that HFHC diet successfully induced liver steatosis to inflammation and fibrosis progressively within 10 weeks. Moreover, HFHC induced the transcriptional expression of lipoprotein lipase (lpl) in the liver, but repressed the expression of LDL receptor, and the endogenous synthesis pathway and excretion of cholesterol. Notably, Poloxamer 407 (P-407) inhibition of LPL improved the severity of steatosis and reduced inflammation. These results illustrated that LPL plays an important role in cholesterol metabolism in NAFLD, and the tree shrew may be a valuable animal model for further research into NAFLD. PMID:26522240

  16. Do geological or climatic processes drive speciation in dynamic archipelagos? The tempo and mode of diversification in Southeast Asian shrews.

    PubMed

    Esselstyn, Jacob A; Timm, Robert M; Brown, Rafe M

    2009-10-01

    Geological and climatic processes potentially alter speciation rates by generating and modifying barriers to dispersal. In Southeast Asia, two processes have substantially altered the distribution of land. Volcanic uplift produced many new islands during the Miocene-Pliocene and repeated sea level fluctuations during the Pleistocene resulted in intermittent land connections among islands. Each process represents a potential driver of diversification. We use a phylogenetic analysis of a group of Southeast Asian shrews (Crocidura) to examine geographic and temporal processes of diversification. In general, diversification has taken place in allopatry following the colonization of new areas. Sulawesi provides an exception, where we cannot reject within-island speciation for a clade of eight sympatric and syntopic species. We find only weak support for temporally declining diversification rates, implying that neither volcanic uplift nor sea level fluctuations had a strong effect on diversification rates. We suggest that dynamic archipelagos continually offer new opportunities for allopatric diversification, thereby sustaining high speciation rates over long periods of time, or Southeast Asian shrews represent an immature radiation on a density-dependent trajectory that has yet to fill geographic and ecological space. PMID:19500148

  17. Cholesterol induces lipoprotein lipase expression in a tree shrew (Tupaia belangeri chinensis) model of non-alcoholic fatty liver disease.

    PubMed

    Zhang, Linqiang; Zhang, Zhiguo; Li, Yunhai; Liao, Shasha; Wu, Xiaoyun; Chang, Qing; Liang, Bin

    2015-01-01

    Animal models are indispensible to investigate the pathogenesis and treatments of non-alcoholic fatty liver diseases (NAFLD). Altered cholesterol metabolism has been implicated into the pathogenesis of NAFLD. Here, using high fat, cholesterol and cholate diet (HFHC), we generated a novel tree shrew (Tupaia belangeri chinensis) model of NAFLD, which displayed dyslipidemia with increased levels of plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST), total cholesterol (TC), low density lipoprotein-cholesterol (LDL-c) and high density lipoprotein-cholesterol (HDL-c), but decreased level of triglycerides (TG). Liver histopathology and genes expression indicated that HFHC diet successfully induced liver steatosis to inflammation and fibrosis progressively within 10 weeks. Moreover, HFHC induced the transcriptional expression of lipoprotein lipase (lpl) in the liver, but repressed the expression of LDL receptor, and the endogenous synthesis pathway and excretion of cholesterol. Notably, Poloxamer 407 (P-407) inhibition of LPL improved the severity of steatosis and reduced inflammation. These results illustrated that LPL plays an important role in cholesterol metabolism in NAFLD, and the tree shrew may be a valuable animal model for further research into NAFLD. PMID:26522240

  18. Delta-9-tetrahydrocannabinol differentially suppresses emesis versus enhanced locomotor activity produced by chemically diverse dopamine D2/D3 receptor agonists in the least shrew (Cryptotis parva).

    PubMed

    Darmani, Nissar A; Crim, Jennifer L

    2005-01-01

    The principal psychoactive component of marijuana, delta-9-tetrahydrocannabinol (Delta9-THC), suppresses nausea and vomiting in cancer patients caused by chemotherapeutics such as cisplatin. Cisplatin induces vomiting via a number of emetic stimuli, including dopamine. Currently, there is controversy as to whether Delta9-THC can prevent emesis produced by dopaminergic agonists such as apomorphine. The present investigation utilizes the least shrew to evaluate the antiemetic potential and the cannabinoid receptor by which Delta9-THC may prevent emesis produced by four dopamine receptor agonists with differing selectivity for D2 and D3 receptors, i.e., a nonselective dopamine receptor agonist (apomorphine), a D2-preferring receptor agonist (quinpirole), and two D3-preferring receptor agonists (quinelorane and 7-OH DPAT). In addition, relative to its antiemetic doses, the motor suppressive doses of Delta9-THC in dopamine D2/D3-receptor-agonist-treated shrews were also evaluated. Thus, different groups of shrews were injected with either vehicle (V) or varying doses of Delta9-THC [0.5, 1, 2.5, 5, or 10 mg/kg, intraperitoneal (i.p.)] 10 min prior to administration of a 2 mg/kg dose of one of the four cited D2/D3 agonists. Immediately after the last injection, the frequency of vomiting for each shrew was recorded for the next 30 min. To investigate which cannabinoid receptor is involved in the antiemetic action of Delta9-THC, various doses of the CB1 receptor antagonist SR 141716A [0, 5, 10, and 20 mg/kg, subcutaneous (s.c.)] were administered to shrews 10 min prior to an injection of a fully effective antiemetic dose of Delta9-THC (5 mg/kg, i.p.). Ten minutes later, each treated shrew was administered with a 2 mg/kg dose of apomorphine. The emesis frequency was recorded for the next 30 min. For locomotor studies, different groups of shrews received either vehicle or various doses of Delta9-THC (0, 5, 10, 20, or 30 mg/kg) 10 min prior to an injection of vehicle or a 2 mg/kg dose of one of the four D2/D3 receptor agonists. The triad of motor behaviors (spontaneous locomotor activity, total duration of movement, and rearing frequency) were recorded for the next 30 min by a computerized video tracking system. Delta9-THC dose-dependently attenuated the frequency of emesis as well as fully protecting shrews from vomiting produced by each one of the four cited dopamine D2/D3 receptor agonists with ID50s ranging from 1 to 4 mg/kg. SR 141716A reversed the antiemetic activity of Delta9-THC against apomorphine-induced emesis. Delta9-THC also differentially suppressed the triad of motor activities in dopamine D2/D3-receptor-agonist-treated shrews with ID50s ranging from 7 to 21 mg/kg. The results suggest that Delta9-THC prevents emesis via cannabinoid CB1 receptors in a potent and dose-dependent manner in D2/D3-receptor-agonist-treated shrews at doses well below those which cause significant motor depression. PMID:15652378

  19. Redescription of Pterygodermatites (Mesopectines) nycticebi (Mnnig, 1920) (Nematoda: Rictulariidae), a parasite of slow loris Nycticebus coucang (Mammalia: Primates).

    PubMed

    Ikeda, Yatsukaho; Fujisaki, Akiko; Murata, Koichi; Hasegawa, Hideo

    2003-06-01

    Pterygodermaties (Mesopectines) nycticebi (Mnnig, 1920) (Nematoda: Spirurida: Rictulariidae) is redescribed based on immature and mature adults collected from the stomach and small intestine at autopsy of a slow loris, Nycticebus coucang (Boddaert, 1785) (Mammalia: Primates), in a zoological garden in Japan. It is first demonstrated that male possesses a minute telamon and a left lateral pore in the preanal part of body. The cause of death of the slow loris is strongly surmised to be related to the nematode infection, which was apparently acquired under captivity in the zoological garden. PMID:14560972

  20. Differential expression of genes during aflatoxin B1-induced hepatocarcinogenesis in tree shrews

    PubMed Central

    Li, Yuan; Wan, Da-Fang; Su, Jian-Jia; Cao, Ji; Ou, Chao; Qiu, Xiao-Kun; Ban, Ke-Chen; Yang, Chun; Qin, Liu-Liang; Luo, Dan; Yue, Hui-Fen; Zhang, Li-Sheng; Gu, Jian-Ren

    2004-01-01

    AIM: Through exploring the regulation of gene expression during hepatocarcinogenesis induced by aflatoxin B1 (AFB1), to find out the responsible genes for hepatocellular carcinoma (HCC) and to further understand the underlying molecular mechanism. METHODS: Tree shrews (Tupaia belangeri chinensis) were treated with or without AFB1 for about 90 weeks. Liver biopsies were performed regularly during the animal experiment. Eight shares of total RNA were respectively isolated from 2 HCC tissues, 2 HCC-surrounding non-cancerous liver tissues, 2 biopsied tissues at the early stage (30th week) of the experiment from the same animals as above, 1 mixed sample of three liver tissues biopsied at the beginning (0th week) of the experiment, and another 1 mixed sample of two liver tissues from the untreated control animals biopsied at the 90th week of the experiment. The samples were then tested with the method of AtlasTM cDNA microarray assay. The levels of gene expression in these tissues taken at different time points during hepatocarcinogenesis were compared. RESULTS: The profiles of differently expressed genes were quite different in different ways of comparison. At the same period of hepatocarcinogenesis, the genes in the same function group usually had the same tendency for up- or down-regulation. Among the checked 588 genes that were known to be related to human cancer, 89 genes (15.1%) were recognized as important genes because they showed frequent changes in different ways of comparison. The differentially expressed genes during hepatocarcinogenesis could be classified into four categories: genes up-regulated in HCC tissue, genes with similar expressing levels in both HCC and HCC-surrounding liver tissues which were higher than that in the tissues prior to the development of HCC, genes down-regulated in HCC tissue, and genes up-regulated prior to the development of HCC but down-regulated after the development of HCC. CONCLUSION: A considerable number of genes could change their expressing levels both in HCC and in HCC-surrounding non-cancerous liver tissues. A few modular genes were up-regulated only in HCC but not in surrounding liver tissues, while some apoptosis-related genes were down-regulated in HCC and up-regulated in surrounding liver tissues. To compare gene-expressing levels among the liver tissues taken at different time points during hepatocarcinogenesis may be helpful to locate the responsible gene (s) and understand the mechanism for AFB1 induced liver cancer. PMID:14966905

  1. Cyclophosphamide causes activation of protein kinase A (PKA) in the brainstem of vomiting least shrews (Cryptotis parva).

    PubMed

    Alkam, Tursun; Chebolu, Seetha; Darmani, Nissar A

    2014-01-01

    Complete control of emesis caused by cyclophosphamide (CPA) is of immense interest to both patients and physicians. Serotonin 5-HT3- and tachykinin NK1-receptor antagonists are widely used antiemetics in clinic, but they fail to completely control CPA-induced emesis. New antiemetic targets for the full control of CPA-induced vomiting are lacking. We therefore examined the effects of CPA on emetic targets downstream of 5-HT3- and NK1- receptors in an attempt to better understand the molecular bases of CPA-induced emesis. Acute CPA (200 mg/kg, i.p.) administration in the least shrew caused a biphasic pattern of emesis over a 40 h observation period, with maximal peak vomit frequency during the 1st hour of treatment (acute phase), followed by a delayed-phase which peaks at 27th hour. The NK1 receptor mRNA levels increased significantly at 8 h post-CPA treatment in the brainstem, and at 28 h in the whole intestine. Substance P mRNA levels tended to increase both in the brainstem and intestine at most time-points post-CPA injection, however due to large variability, they failed to attain significance. Likewise, protein expression profiles of both NK1- and 5-HT3 -receptors in the brainstem were unchanged at any time-point. However, phosphorylation levels of protein kinase A (PKA), but not of extracellular signal-regulated protein kinase 1/2 (ERK1/2), were increased at 2, 8, 22, 28, and 33 h time-points after the treatment with CPA. Moreover, brainstem but not frontal cortex cAMP tissue levels tended to be elevated at most time-points, but significant increases occurred only at 1 and 2 h post-CPA treatment. The phosphodiesterase inhibitor, rolipram, caused significant increases in shrew brainstem cAMP levels which were associated with its capacity to produce vomiting, while pretreatment with SQ22536, an inhibitor of adenylyl cyclase, prevented rolipram-induced emesis. The results demonstrate that accumulation of cAMP and subsequent activation of PKA in the brainstem may help to initiate and sustain emesis induced by CPA in the least shrew. Our findings suggest that suppression of the cAMP/PKA cascade may have antiemetic potential in the management of CPA-induced emesis. PMID:24513510

  2. Synergy between cannabidiol, cannabidiolic acid, and ??-tetrahydrocannabinol in the regulation of emesis in the Suncus murinus (house musk shrew).

    PubMed

    Rock, Erin M; Parker, Linda A

    2015-06-01

    Smoked marijuana contains over 100 different cannabinoids, including the psychoactive compound ?9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC, CBD, and its acidic precursor, cannabidiolic acid (CBDA), have all been shown to have antiemetic properties in the Suncus murinus (S. murinus; house musk shrew). Here we show that when subthreshold antiemetic doses of CBD (2.5 mg/kg ip) or CBDA (0.05 mg/kg ip) are combined with a subthreshold antiemetic dose of THC (1 mg/kg ip) in the S. murinus, both lithium-chloride-induced vomiting and abdominal retching are dramatically suppressed. These results suggest that combined effects of these compounds may lead to better control of vomiting with fewer side effects. PMID:26030435

  3. Interglacial refugia preserved high genetic diversity of the Chinese mole shrew in the mountains of southwest China.

    PubMed

    He, K; Hu, N-Q; Chen, X; Li, J-T; Jiang, X-L

    2016-01-01

    The mountains of southwest China (MSC) harbor extremely high species diversity; however, the mechanism behind this diversity is unknown. We investigated to what degree the topography and climate change shaped the genetic diversity and diversification in these mountains, and we also sought to identify the locations of microrefugia areas in these mountains. For these purposes, we sampled extensively to estimate the intraspecific phylogenetic pattern of the Chinese mole shrew (Anourosorex squamipes) in southwest China throughout its range of distribution. Two mitochondrial genes, namely, cytochrome b (CYT B) and NADH dehydrogenase subunit 2 (ND2), from 383 archived specimens from 43 localities were determined for phylogeographic and demographic analyses. We used the continuous-diffusion phylogeographic model, extensive Bayesian skyline plot species distribution modeling (SDM) and approximate Bayesian computation (ABC) to explore the changes in population size and distribution through time of the species. Two phylogenetic clades were identified, and significantly higher genetic diversity was preserved in the southern subregion of the mountains. The results of the SDM, continuous-diffusion phylogeographic model, extensive Bayesian skyline plot and ABC analyses were congruent and supported that the Last Interglacial Maximum (LIG) was an unfavorable period for the mole shrews because of a high degree of seasonality; A. squamipes survived in isolated interglacial refugia mainly located in the southern subregion during the LIG and rapidly expanded during the last glacial period. These results furnished the first evidence for major Pleistocene interglacial refugia and a latitudinal effect in southwest China, and the results shedding light on the higher level of species richness in the southern subregion. PMID:26286667

  4. Computerized detection and analysis of cancer chemotherapy-induced emesis in a small animal model, musk shrew

    PubMed Central

    Huang, Dong; Meyers, Kelly; Henry, Sverine; De la Torre, Fernando; Horn, Charles C.

    2011-01-01

    Vomiting is a common side effect of cancer chemotherapy and many drug treatments and diseases. In animal studies, the measurement of vomiting usually requires direct observation, which is time consuming and often lacks temporal precision. Musk shrews have been used to study the neurobiology of emesis and have a rapid emetic episode (~1 s for a sequence of retching and expulsion). The aims of the current study were to develop a method to automatically detect and characterize emetic episodes induced by the cancer chemotherapy agent cisplatin. The body contour in each video frame was tracked and normalized to a parameterized shape basis. The tracked shape was projected to a feature space that maximizes the shape variations in the consecutive frames during retching. The resulting one dimensional projection was sufficient to detect most emetic episodes in the acute (peak at 2 h) and delayed (peak at 54 h) phases after cisplatin treatment. Emetic episodes were relatively invariant in the number of retches (~6.2), duration (~1.2 s), inter-retch interval (~198 ms), and amplitude during the 72 h after cisplatin treatment. This approach should open a new vista into emesis research to permit tracking and analysis of emesis in small animal models and facilitate the development of new antiemetic therapies. These results also yield a better understanding of the brains central pattern generator for emesis and indicate that the retching response in the musk shrew (at ~5.4 Hz) is the fastest ever recorded in a free-moving animal. PMID:21392533

  5. Heart and respiratory rates and their significance for convective oxygen transport rates in the smallest mammal, the Etruscan shrew Suncus etruscus.

    PubMed

    Jrgens, K D; Fons, R; Peters, T; Sender, S

    1996-12-01

    Heart and respiratory rates of the smallest mammal (mean adult body mass 2g), the Etruscan shrew Suncus etruscus, were determined at rest and under stress conditions. Heart rate was obtained from electrocardiograms (ECGs), recorded via foot electrodes. The mean +/- S.D. heart rate of resting animals (ambient temperature 22 degrees C) was 835 +/- 107 min-1, the mean maximal rate amounted to 1093 +/- 235 min-1. The highest single value recorded was 1511 min-1, which is the highest heart rate reported so far for an endotherm. The respiratory rate was also obtained from ECG recordings, which showed the electrical activity of the breathing muscles during inhalation, and additionally by recording the movements of the thoracic wall with a laser autofocus system. The mean resting respiratory rate was 661 +/- 93 min-1, the mean maximal rate was 758 +/- 109 min-1 and the highest single value recorded was 894 min-1. At 22 degrees C, the specific oxygen consumption rate is 67 times higher in resting S. etruscus than in resting humans. Under these conditions, the respiratory rate of the shrew is 47 times higher but the heart rate only 12 times higher than in man. Therefore, to achieve an adequate circulatory oxygen transport rate, the product of relative stroke volume and arterio-venous O2 difference has to be 5.6 times higher in the shrew than in man, whereas for an appropriate ventilatory oxygen transport rate the product of relative tidal volume and oxygen extraction has to be only 1.4 times higher in this small insectivore than in man. The maximal possible oxygen transport rates of the ventilatory and the circulatory system have been estimated and compared with the diffusional transport capacity of the lung. These rates amount to approximately 1000 ml O2 kg-1 min-1. According to our results and data in the literature, an aerobic scope of 7-10 seems to be realistic for the Etruscan shrew. PMID:9110952

  6. The role of D2 and D3 dopamine receptors in the mediation of emesis in Cryptotis parva (the least shrew).

    PubMed

    Darmani, N A; Zhao, W; Ahmad, B

    1999-01-01

    This study introduces Cryptotis parva (the least shrew) as a new dopaminergic animal model of emesis. The potential emetogenic effects of a nonselective dopamine agonist [apomorphine], two D1 agonists [SKF-38393 and SKF-82958], a D2 preferring agonist [quinpirole], and two D3-preferring agonists [7-(OH) DPAT and PD 128, 907] were investigated. Intraperitoneal administration of D1 agonists failed to induce emesis. However, other agonists caused a dose-dependent increase in the percentage of animals vomiting as well as potentiating the mean frequency of emesis with the following ED50, potency order: 7-(OH) DPAT < apomorphine < quinpirole < PD 128, 907. For antagonist studies a 2 mg/kg dose of these agonists were used to induce emesis. Thus, the inhibitory dose-response effects of a D2-preferring [sulpride], a D3-preferring [U 99194A] and combination of varying doses of these antagonists [sulpride + U 99194A] were evaluated on the ability of the cited agonists to produce vomiting. Sulpride decreased the number of shrews vomiting and the mean vomiting frequency produced by the cited agonists in a dose-dependent fashion with the following ID50 order [apomorphine < PD 128, 907 < 7-(OH) DPAT < quinpirole]. By itself, U 99194A failed to significantly alter the emesis produced by any of the cited agonists, however, it potentiated (3-8 times) the antiemetic effects of sulpride both in reducing the number of shrews vomiting as well as decreasing the mean vomiting frequency with the following ID50 order: PD 128, 907 < 7-(OH) DPAT < quinpirole. However, U 99194A attenuated the potent antiemetic effect of sulpride on the apomorphine-induced emesis. The results suggest that the tested agonists primarily activate dopamine D2 receptors to induce emesis in the least shrew whereas activation of D3 sites potentiate the vomiting action of D2 dopamine receptors. PMID:10651102

  7. A network approach to study karyotypic evolution: the chromosomal races of the common shrew (Sorex araneus) and house mouse (Mus musculus) as model systems.

    PubMed

    White, Thomas A; Bordewich, Magnus; Searle, Jeremy B

    2010-05-01

    The development of methods to reconstruct phylogenies from karyotypic data has lagged behind what has been achieved with molecular and morphological characters. This hampers our understanding of the role of chromosomal rearrangements in speciation, which depends on knowledge of the karyotypic relationships both among forms that have recently speciated and among forms within species that may speciate in the future. Here, we present a new approach to reconstruct chromosomal phylogenies. Our approach involves the use of networks, which we believe offer a flexible alternative to bifurcating phylogenetic trees for chromosomal phylogenetic analyses, and can incorporate a wide range of chromosomal mutations as well as allowing reticulate evolution through hybridization. In this paper, we apply our method at the within-species level to establish the phylogenetic history, in terms of minimum number of evolutionary steps, of chromosomal races within both the common shrew (Sorex araneus) and the house mouse (Mus musculus). There have been several previous attempts to reconstruct the phylogenies of chromosomal races within shrews and mice, but we describe the first computer-based analysis that considers the whole range of possible mutations generating new races (Robertsonian fusions and fissions and whole-arm reciprocal translocations [WARTs]) and other race-generating processes (zonal raciation events involving both acrocentric and recombinant peaks) postulated for these species. The analysis for common shrew chromosomal races reveals a greater importance of zonal raciation and WARTs than has been suggested hitherto. PMID:20525634

  8. Distribution of Borna disease virus antigen and RNA in tissues of naturally infected bicolored white-toothed shrews, Crocidura leucodon, supporting their role as reservoir host species.

    PubMed

    Puorger, M E; Hilbe, M; Mller, J-P; Kolodziejek, J; Nowotny, N; Zlinszky, K; Ehrensperger, F

    2010-03-01

    Borna disease is a severe viral-induced disorder of the central nervous system of horses, sheep, and a few other animal species, occurring in certain areas of central Europe. Pathogenesis and epidemiology of natural Borna disease virus (BDV) infections are still not fully understood; several unique epidemiologic features, however, point toward the existence of BDV reservoir populations other than the final hosts. In this study, 69 mice and 12 shrews were trapped and examined. The virus distribution was investigated in detail in 2 BDV-positive bicolored white-toothed shrews, Crocidura leucodon, by immunohistochemistry and TaqMan real-time reverse transcription polymerase chain reaction (RT-PCR). RT-PCR amplification products were sequenced, and the sequences were compared. These shrews had been collected in a BDV-endemic geographical region using live traps and did not show obvious clinical or pathological disease signs. BDV antigen and nucleic acid were identified in several organs, including the brain, mainly in nerve tissue and neurons, respectively, but also in parenchymal cells (eg, hepatocytes, Leydig cells) and epithelial cells, particularly of the respiratory and urogenital tract. PMID:20133953

  9. Feeding mechanics and dietary implications in the fossil sloth Neocnus (Mammalia: Xenarthra: Megalonychidae) from Haiti.

    PubMed

    McAfee, Robert K

    2011-10-01

    Haitian species of the extinct ground sloth genus Neocnus (Mammalia: Pilosa: Megalonychidae) have previously been hypothesized to have a much reduced jugal bone and a correspondingly reduced masseter musculature but a paucity of specimens has prevented further investigation of this hypothesis. Recent discovery of jugal bones belonging to Haitian specimens of Neocnus within the University of Florida Museum collections enables the element to be more accurately described. The discovery also makes it possible to explore mastication in these sloths. Osteological characters related to feeding were examined, along with comparative estimations of bite force with the extant tree sloths, Bradypus and Choloepus, and their known dietary habits as a means to infer aspects of the paleodiet of Neocnus. There is a significant difference in moment arm calculations for m. masseter between predicted and actual jugals, but the overall significance for bite force is lost and hampered by small sample size. Neocnus demonstrates a variety of characters that are similar to those of Bradypus and not to Choloepus, which is a close phylogenetic relative. The masticatory musculature of Neocnus enabled a chewing cycle emphasizing a grinding combination of mesiodistal and linguobuccal movements of the molariform dentition. The orientations of m. masseter and m. temporalis are estimated to produce relatively high bite force ratios that imply a masticatory system with stronger versus faster components. Because of the similarity of bite forces and jaw mechanics to those of Bradypus, in addition to a number of osteological adaptations indicative of herbivorous grazers (elevated mandibular condyle, large and complex masseter, and robust angular process), the Haitian forms of Neocnus are considered to have been selective feeders with a folivorous diet. PMID:21638306

  10. Identification of Specialists and Abundance-Occupancy Relationships among Intestinal Bacteria of Aves, Mammalia, and Actinopterygii.

    PubMed

    Green, Hyatt C; Fisher, Jenny C; McLellan, Sandra L; Sogin, Mitchell L; Shanks, Orin C

    2015-01-01

    The coalescence of next-generation DNA sequencing methods, ecological perspectives, and bioinformatics analysis tools is rapidly advancing our understanding of the evolution and function of vertebrate-associated bacterial communities. Delineation of host-microbe associations has applied benefits ranging from clinical treatments to protecting our natural waters. Microbial communities follow some broad-scale patterns observed for macroorganisms, but it remains unclear how the specialization of intestinal vertebrate-associated communities to a particular host environment influences broad-scale patterns in microbial abundance and distribution. We analyzed the V6 region of 16S rRNA genes amplified from 106 fecal samples spanning Aves, Mammalia, and Actinopterygii (ray-finned fish). We investigated the interspecific abundance-occupancy relationship, where widespread taxa tend to be more abundant than narrowly distributed taxa, among operational taxonomic units (OTUs) within and among host species. In a separate analysis, we identified specialist OTUs that were highly abundant in a single host and rare in all other hosts by using a multinomial model without excluding undersampled OTUs a priori. We show that intestinal microbes in humans and other vertebrates display abundance-occupancy relationships, but because intestinal host-associated communities have undergone intense specialization, this trend is violated by a disproportionately large number of specialist taxa. Although it is difficult to distinguish the effects of dispersal limitations, host selection, historical contingency, and stochastic processes on community assembly, results suggest that intestinal bacteria can be shared among diverse hosts in ways that resemble the distribution of "free-living" bacteria in the extraintestinal environment. PMID:26712546

  11. Mitochondrial cytochrome b of the Lyakhov mammoth (Proboscidea, Mammalia): new data and phylogenetic analyses of Elephantidae.

    PubMed

    Debruyne, Rgis; Barriel, Vronique; Tassy, Pascal

    2003-03-01

    The phylogenetic relationships between recent Elephantidae (Proboscidea, Mammalia), that is to say extant elephants (Asian and African) and extinct woolly mammoth, have remained unclear to date. The prevailing morphological scheme (mammoth grouped with Asian elephant) is either supported or questioned by the molecular results. Recently, the monophyly of woolly mammoths on mitochondrial grounds has been demonstrated (Thomas, et al., 2000), but it conflicts with previous studies (Barriel et al., 1999; Derenko et al., 1997). Here, we report the partial sequencing of two mitochondrial genes: 128 bp of 12S rDNA and 561 bp of cytochrome b for the Lyakhov mammoth, a 49,000-year-old Siberian individual. We use the most comprehensive sample of mammoth (11 sequences) to determine whether the sequences achieved by former studies were congruent or not. The monophyly of a major subset of mammoths sequences (including ours) is recovered. Such a result is assumed to be a good criterion for ascertaining the origin of ancient DNA. Our sequence is incongruent with that of Yang et al. (1996), though obtained for the same individual. As far as the latter sequence is concerned, a contamination by non-identified exogenous DNA is suspected. The robustness and reliability of the sister group relation between Mammuthus primigenius and Loxodonta africana are examined: down-weighting saturated substitutions has no impact on the topology; analyzing data partitions proves that the support of this clade can be assigned to the most conservative phylogenetic signal; insufficient taxonomic and/or characters sampling contributed to former discordant conclusions. We therefore assume the monophyly of "real mammoth sequences" and the (Mammuthus, Loxodonta) clade. PMID:12644401

  12. Receptor mechanism and antiemetic activity of structurally diverse cannabinoids against radiation-induced emesis in the Least shrew

    PubMed Central

    Darmani, Nissar A.; Janoyan, Jano J.; Crim, Jennifer; Ramirez, Juan

    2007-01-01

    Xenobiotic cannabinoid CB1/CB2-receptor agonists appear to possess broad-spectrum antiemetic activity since they prevent vomiting produced by a variety of emetic stimuli including the chemotherapeutic agent cisplatin, serotonin 5-HT3-receptor agonists, dopamine D2/D3-receptor agonists and morphine, via the stimulation of CB1-receptors. The purpose of this study was to evaluate whether structurally diverse cannabinoids [?9-THC, (delta -9- tetrahydrocannabinol); (?8-THC, delta -8-etrahydrocannabinol); WIN55,212-2, (R (+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)), methyl] pyrolol [1, 2, 3 de] 1, 4 benzoxazinyl] (1-naphthalenyl) methenone mesylate); and CP55,940, ((-) - 3- [2-hydroxy-4- (1,1 - dimethylheptyl] - 4 [3 hydroxypropyl] cyclohexan 1 ol)), can prevent radiation-induced emesis. Exposure to total body radiation (0, 5, 7.5 and 10 Gy) caused robust emesis in the least shrew (Cryptotis parva) in a dose-dependent manner (ED50= 5.99 (5.77 6.23) Gy) and all animals vomited at the highest tested dose of radiation. In addition, the radiation exposure reduced locomotor behaviors to a significant but mild degree in a non-dose-dependent fashion up to one hour posttreatment. Radiation-induced emesis (10 Gy) was blocked in a dose-dependent manner by the CB1/CB2 receptor agonists with the following ID50potency order: CP55,940 (0.11 (0.09 - 0.12) mg/kg) > WIN55, 212,2 (3.65 (3.15 4.23) mg/kg) = ?8-THC (4.36 (3.05 6.22) mg/kg) > ? 9-THC (6.76 (5.22 8.75) mg/kg). Although the greater antiemetic potency and efficacy of ?8-THC relative to its isomer ?9-THC is unusual as the latter cannabinoid possesses higher affinity and potency for cannabinoid receptors in functional assays, the current data support the results of a clinical study in children suggestive of complete protection from emesis by ?8-THC. This effect has not been clinically observed for ?9-THC in cancer patients receiving chemo- or radiation-therapy.Cannabinoids prevented the induced emesis via the stimulation of cannabinoid CB1- receptors because the CB1(SR141716A) and not the CB2(SR144528) receptor antagonist reversed both the observed reduction in emesis frequency and shrew emesis protection afforded by either ?9-THC or CP55,940 against radiation-induced emesis. These findings further suggest that the least shrew can be utilized as a versatile and inexpensive small animal model to rapidly screen the efficacy of investigational antiemetics for the prevention of radiation-induced emesis. PMID:17362921

  13. Receptor mechanism and antiemetic activity of structurally-diverse cannabinoids against radiation-induced emesis in the least shrew.

    PubMed

    Darmani, Nissar A; Janoyan, Jano J; Crim, Jennifer; Ramirez, Juan

    2007-06-01

    Xenobiotic cannabinoid CB1/CB2-receptor agonists appear to possess broad-spectrum antiemetic activity since they prevent vomiting produced by a variety of emetic stimuli including the chemotherapeutic agent cisplatin, serotonin 5-HT3-receptor agonists, dopamine D2/D3-receptor agonists and morphine, via the stimulation of CB1-receptors. The purpose of this study was to evaluate whether structurally-diverse cannabinoids [Delta9-THC, (delta-9-tetrahydrocannabinol); (Delta8-THC, delta-8-tetrahydrocannabinol); WIN55,212-2, (R (+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)), methyl] pyrolol [1,2,3-de]-1,4 benzoxazinyl]-(1-naphthalenyl) methenone mesylate); and CP55,940, ((-)-3-[2-hydroxy-4-(1,1-dimethylheptyl]-4-[3-hydroxypropyl] cyclohexane-1-ol)), can prevent radiation-induced emesis. Exposure to total body radiation (0, 5, 7.5 and 10 Gy) caused robust emesis in the least shrew (Cryptotis parva) in a dose-dependent manner (ED50=5.99 (5.77-6.23) Gy) and all animals vomited at the highest tested dose of radiation. In addition, the radiation exposure reduced locomotor behaviors to a significant but mild degree in a non-dose-dependent fashion up to one hour post-treatment. Radiation-induced emesis (10 Gy) was blocked in a dose-dependent manner by the CB1/CB2-receptor agonists with the following ID50 potency order: CP55,940 (0.11 (0.09-0.12) mg/kg)>WIN55,212,2 (3.65 (3.15-4.23) mg/kg)=Delta8-THC (4.36 (3.05-6.22) mg/kg)>Delta9-THC (6.76 (5.22-8.75) mg/kg). Although the greater antiemetic potency and efficacy of Delta8-THC relative to its isomer Delta9-THC is unusual as the latter cannabinoid possesses higher affinity and potency for cannabinoid receptors in functional assays, the current data support the results of a clinical study in children suggestive of complete protection from emesis by Delta8-THC. This effect has not been clinically observed for Delta9-THC in cancer patients receiving chemo- or radiation-therapy. Cannabinoids prevented the induced emesis via the stimulation of cannabinoid CB1-receptors because the CB1 (SR141716A)--and not the CB2 (SR144528)--receptor antagonist reversed both the observed reduction in emesis frequency and shrew emesis protection afforded by either Delta9-THC or CP55,940 against radiation-induced emesis. These findings further suggest that the least shrew can be utilized as a versatile and inexpensive small animal model to rapidly screen the efficacy of investigational antiemetics for the prevention of radiation-induced emesis. PMID:17362921

  14. Une nouvelle espce d'hyracode du genre Bunohyrax (Mammalia) de l'ocne de Bir El Ater (Algrie).

    NASA Astrophysics Data System (ADS)

    Tabuce, Rodolphe; Coiffait, Brigitte; Coiffait, Philippe-Emmanuel; Mahboubi, Mohamed; Jaeger, Jean-Jacques

    2000-07-01

    A new species of Bunohyrax, B. matsumotoi n. sp. (Hyracoidea, Mammalia) from the Bir El Ater locality (Algeria) is described and compared with the two known species from the Oligocene of the Fayum (Egypt). This new hyracoid is documented by fragmentary remains, but the characters are significant enough to establish a new species, particularly because of its extremely small size. B. matsumotoi appears to be more primitive than the Egyptian Bunohyrax. The Algerian species, together with geological and palaeontological data, argues for a late Middle to Late Eocene age for the Bir El Ater site, rather than an Oligocene age, equivalent to the upper sequence of the Fayum, as suggested by Rasmussen et al. [17].

  15. Dental microwear in relation to changes in the direction of mastication during the evolution of Myodonta (Rodentia, Mammalia)

    NASA Astrophysics Data System (ADS)

    Charles, Cyril; Jaeger, Jean-Jacques; Michaux, Jacques; Viriot, Laurent

    2007-01-01

    Observations of dental microwear are used to analyse the correlation between changes in molar tooth crown morphology and the direction of masticatory movement during the evolution of Myodonta (Rodentia, Mammalia). The studied sample includes 36 specimens representing both superfamilies of Myodonta (Muroidea and Dipodoidea) spanning 16 dipodoid and 9 muroid species. Microscopic scratches on occlusal surfaces resulting from contact between opposite teeth during mastication are analysed. Using these features, we determine the direction of masticatory movements. Microwear patterns display diverse orientations among Dipodoidea: oblique in Sicistinae, Euchoreutinae and Zapodinae, propalinal in Dipodinae and intermediary in Allactaginae. Similarly, Muroidea exhibit the following orientations: oblique in Cricetinae and propalinal in Arvicolinae, Cricetomyinae, Gerbillinae and Murinae. These various chewing types illustrate different evolutionary grades within the superfamilies. Acquisition of the antero-posterior masticatory movement in Dipodoidea is related to flattening of the molar occlusal surface. However, in some muroid subfamilies, this direction of mastication is associated with low-crowned and cuspidate molars (Cricetomyinae, Murinae).

  16. Selective Regulation of MMP and TIMP mRNA Levels in Tree Shrew Sclera during Minus Lens Compensation and Recovery

    PubMed Central

    Siegwart, John T.; Norton, Thomas T.

    2007-01-01

    Purpose In juvenile tree shrews, a minus-power lens placed in front of the eye produces increased axial elongation and a myopic shift in refractive state that compensates for the power of the lens. Scleral tissue remodeling and modulation of the mechanical properties of the sclera occur during lens compensation. In this study, the time course of changes in scleral mRNA levels of three MMPs and three TIMPs during compensation for a minus lens and during recovery was investigated, to determine which, if any, are temporally associated with changes in the mechanical properties of the sclera and the axial elongation rate. Methods Competitive RT-PCR was used to measure the levels of mRNA for MT1-MMP, MMP-2, MMP-3, TIMP-1, TIMP-2, and TIMP-3 in the scleras of tree shrews that had received either 1, 2, 4, or 11 days of monocular ?5-D lens treatment, or 11 days of ?5-D lens treatment followed by 2 or 4 days of recovery. Results Relative to their control eyes, treated eye MT1-MMP and MMP-2 mRNA levels were significantly higher, and TIMP-3 levels were lower by 1 to 4 days of minus lens treatment. These differential effects were absent by 11 days of treatment when the treated eyes had compensated for the lens. The levels of all three TIMPs spiked upward in both eyes after 2 days of recovery. The differential changes in MT1-MMP, MMP-2, and TIMP-3 mRNA levels were all restricted to the treated eye and were temporally associated with the differential changes in axial elongation, refractive state, and the previously measured changes in creep rate. Conclusions The observed changes in MT1-MMP, MMP-2, TIMP-2, and TIMP-3 mRNA are consistent with visually modulated MT1-MMP activation of MMP-2 and with MT1-MMP degradation of scleral extracellular matrix components. These data constitute further evidence that visual signals modulate gene expression of selected MMPs and TIMPs to control scleral remodeling, the mechanical properties of the sclera, axial elongation, and refractive state. PMID:16186323

  17. The Time Course of Changes in mRNA Levels in Tree Shrew Sclera during Induced Myopia and Recovery

    PubMed Central

    Siegwart, John T.; Norton, Thomas T.

    2007-01-01

    Purpose In tree shrews, visual form deprivation produces increased axial elongation of the deprived eye and a myopic shift in refractive state. A change in scleral extensibility (creep rate) is closely associated with the change in axial elongation rate. These effects may be due to scleral tissue remodeling produced by a change in scleral gene expression. In this study, the authors investigated the time course of changes in scleral mRNA levels for selected proteins during the development of form deprivation myopia and during recovery, to determine which, if any, are temporally associated with changes in scleral extensibility and axial elongation rate. Methods Competitive RT-PCR was used to measure the levels of mRNA for structural proteins (collagen [?1(I) chain], decorin core protein), degradative enzymes (MMP-2 [gelatinase-A], MMP-3 [stromelysin-1]), and a tissue inhibitor of metalloproteinase (TIMP-1) in the scleras of tree shrews that had been subjected to 1, 2, 4, or 11 days of monocular form deprivation (MD) or 11 days of MD followed by 2 or 4 days of recovery produced by removal of the MD. Four groups of normal animals provided age-matched normal data. Results Compared with the control eyes, deprived-eye MMP-2 mRNA levels were higher and MMP-3 levels were lower after 4 days of MD. Deprived-eye collagen mRNA levels were lower than control eye levels after 11 days of MD. The differential effects produced by MD were absent after 2 days of recovery and generally were reversed after 4 days. Decorin mRNA levels in the deprived and control eyes were not significantly different during either MD or recovery. During MD, mRNA levels for collagen, MMP-3, and TIMP-1 decreased in both the deprived and control eyes, compared with age-matched normal eyes. The binocular changes in collagen and TIMP-1 mRNA levels and the differential changes in MMP-2 and MMP-3 levels were detected at least as early as axial, refractive, and creep rate changes. Conclusions The up- and downregulation of the specific mRNAs studied, on a time course similar to that for physical changes in the sclera, suggests that modulation of gene expression by the visual environment may produce scleral remodeling and changes in scleral creep rate during the development of form deprivation myopia and recovery. PMID:12091398

  18. Broad-spectrum antiemetic efficacy of the L-type calcium channel blocker amlodipine in the least shrew (Cryptotis parva).

    PubMed

    Zhong, Weixia; Chebolu, Seetha; Darmani, Nissar A

    2014-05-01

    The dihydropyridine l-type calcium (Ca(2+)) channel blockers nifedipine and amlodipine reduce extracellular Ca(2+) entry into cells. They are widely used for the treatment of hypertensive disorders. We have recently demonstrated that extracellular Ca(2+) entry via l-type Ca(2+) channels is involved in emesis and that nifedipine has broad-spectrum antiemetic activity. The aim of this study was to evaluate the antiemetic efficacy of the longer-acting l-type Ca(2+) channel blocker, amlodipine. Fully effective emetic doses of diverse emetogens such as the l-type Ca(2+) channel agonist (FPL 64176) as well as selective and/or nonselective agonists of serotonergic 5-HT3 (e.g. 5-HT or 2-Me-5-HT)-, dopamine D2 (e.g. apomorphine or quinpirole)-, cholinergic M1 (e.g. pilocarpine or McN-A343)- and tachykininergic NK1 (e.g. GR73632)-receptors, were administered intraperitoneally (i.p.) in the least shrew to induce vomiting. The broad-spectrum antiemetic potential of amlodipine was evaluated against these emetogens. Subcutaneous (s.c.) administration of amlodipine (0.5-10mg/kg) attenuated in a dose-dependent and potent manner both the frequency and percentage of shrews vomiting in response to intraperitoneal (i.p.) administration of FPL 64176 (10mg/kg), 5-HT (5mg/kg), 2-Me-5-HT (5mg/kg), apomorphine (2mg/kg), quinpirole (2mg/kg), pilocarpine (2mg/kg), McN-A343 (2mg/kg), or GR73632 (5mg/kg). A combination of non-effective doses of amlodipine (0.5mg/kg, s.c.) and the 5-HT3 receptor antagonist palonosetron (0.05 mg/kg, s.c.) was more effective against FPL 64176-induced vomiting than their corresponding doses tested alone. Amlodipine by itself suppressed the frequency of acute cisplatin (10mg/kg, i.p)-induced vomiting in a dose-dependent manner. Moreover, a combination of a non-effective dose of amlodipine (1mg/kg) potentiated the antiemetic efficacy of a semi-effective dose of palonosetron (0.5mg/kg, s.c.) against acute vomiting caused by cisplatin. We confirm that influx of extracellular Ca(2) ion underlies vomiting due to diverse causes and demonstrate that l-type Ca(2+) channel blockers are a new class of broad-spectrum antiemetics. PMID:24631485

  19. Postpartum erythrophagocytosis, iron storage and iron secretion in the endometrium of the tree shrew (Tupaia) during pregnancy.

    PubMed Central

    Zeller, U; Kuhn, H J

    1994-01-01

    Tree shrews (Tupaia belangeri) develop a bidiscoid endotheliochorial placenta. In addition, histiotrophe secreted by uterine glands is absorbed by the paraplacental trophoblast. Histiotrophe which is rich in iron is necessary for erythropoiesis in the young embryo. This report is part of a study of the accumulation and metabolism of iron in the endometrium of precisely dated pregnant Tupaia belangeri by application of electron spectroscopy and histochemistry. In the endometrium of tree shrews which had been pregnant at least once, iron-laden granules were present in macrophages and secreting cells of uterine glands. Iron accumulated in the endometrium shortly after parturition, when macrophages phagocytosed erythrocytes at small haematomas 0.2-0.5 mm in diameter. These haematomas arose during parturition after bleeding into the uterine stroma when the placental discs were detached. At 24 h after parturition the following structural consequences of the erythrolysosomal breakdown of phagocytosed erythrocytes could be observed: free cytosolic siderin granules, membrane-bound siderosomes, telolysosomes (some of which contained myelin figures or lipid droplets) and mixed telolysosomes (containing membranous stacks and siderin granules). During the lysosomal degradation of phagocytosed erythrocytes, iron was transferred from haemoglobin into a different macromolecular compound. Electron energy loss spectra detected from inside siderosomes indicated an iron-oxygen compound, and high-power bright field electron micrographs of siderosomes demonstrated the ultrastructural pattern characteristic of ferritin. At about d 12 of a new pregnancy, macrophages containing siderosomes closely approached the bases of secreting cells of endometrial glands. This strongly suggests that iron is transferred from the macrophages to the glandular cells. Within the glandular cells, iron-rich histiotrophe was synthesised and released into the glandular lumen. Within the uterine cavity this histiotrophe was absorbed by the omphalopleure. We suggest that among eutherians, postpartum erythrophagocytosis, the transfer of iron from macrophages to uterine glands, and the paraplacental uptake of iron, represent an ancestral mechanism of iron supply to the embryo. Images Fig. 1 Fig. 2 Figs. 3-4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7928647

  20. Digital Cranial Endocast of Hyopsodus (Mammalia, Condylarthra): A Case of Paleogene Terrestrial Echolocation?

    PubMed Central

    Orliac, Maeva J.; Argot, Christine; Gilissen, Emmanuel

    2012-01-01

    We here describe the endocranial cast of the Eocene archaic ungulate Hyopsodus lepidus AMNH 143783 (Bridgerian, North America) reconstructed from X-ray computed microtomography data. This represents the first complete cranial endocast known for Hyopsodontinae. The Hyopsodus endocast is compared to other known condylarthran endocasts, i. e. those of Pleuraspidotherium (Pleuraspidotheriidae), Arctocyon (Arctocyonidae), Meniscotherium (Meniscotheriidae), Phenacodus (Phenacodontidae), as well as to basal perissodactyls (Hyracotherium) and artiodactyls (Cebochoerus, Homacodon). Hyopsodus presents one of the highest encephalization quotients of archaic ungulates and shows an advanced version of the basal ungulate brain pattern, with a mosaic of archaic characters such as large olfactory bulbs, weak ventral expansion of the neopallium, and absence of neopallium fissuration, as well as more specialized ones such as the relative reduction of the cerebellum compared to cerebrum or the enlargement of the inferior colliculus. As in other archaic ungulates, Hyopsodus midbrain exposure is important, but it exhibits a dorsally protruding largely developed inferior colliculus, a feature unique among Condylarthra. A potential correlation between the development of the inferior colliculus in Hyopsodus and the use of terrestrial echolocation as observed in extant tenrecs and shrews is discussed. The detailed analysis of the overall morphology of the postcranial skeleton of Hyopsodus indicates a nimble, fast moving animal that likely lived in burrows. This would be compatible with terrestrial echolocation used by the animal to investigate subterranean habitat and/or to minimize predation during nocturnal exploration of the environment. PMID:22347998

  1. Digital cranial endocast of Hyopsodus (Mammalia, "Condylarthra"): a case of paleogene terrestrial echolocation?

    PubMed

    Orliac, Maeva J; Argot, Christine; Gilissen, Emmanuel

    2012-01-01

    We here describe the endocranial cast of the Eocene archaic ungulate Hyopsodus lepidus AMNH 143783 (Bridgerian, North America) reconstructed from X-ray computed microtomography data. This represents the first complete cranial endocast known for Hyopsodontinae. The Hyopsodus endocast is compared to other known "condylarthran" endocasts, i. e. those of Pleuraspidotherium (Pleuraspidotheriidae), Arctocyon (Arctocyonidae), Meniscotherium (Meniscotheriidae), Phenacodus (Phenacodontidae), as well as to basal perissodactyls (Hyracotherium) and artiodactyls (Cebochoerus, Homacodon). Hyopsodus presents one of the highest encephalization quotients of archaic ungulates and shows an "advanced version" of the basal ungulate brain pattern, with a mosaic of archaic characters such as large olfactory bulbs, weak ventral expansion of the neopallium, and absence of neopallium fissuration, as well as more specialized ones such as the relative reduction of the cerebellum compared to cerebrum or the enlargement of the inferior colliculus. As in other archaic ungulates, Hyopsodus midbrain exposure is important, but it exhibits a dorsally protruding largely developed inferior colliculus, a feature unique among "Condylarthra". A potential correlation between the development of the inferior colliculus in Hyopsodus and the use of terrestrial echolocation as observed in extant tenrecs and shrews is discussed. The detailed analysis of the overall morphology of the postcranial skeleton of Hyopsodus indicates a nimble, fast moving animal that likely lived in burrows. This would be compatible with terrestrial echolocation used by the animal to investigate subterranean habitat and/or to minimize predation during nocturnal exploration of the environment. PMID:22347998

  2. Bony labyrinth morphometry indicates locomotor adaptations in the squirrel-related clade (Rodentia, Mammalia).

    PubMed

    Pfaff, Cathrin; Martin, Thomas; Ruf, Irina

    2015-06-22

    The semicircular canals (SCs) of the inner ear detect angular acceleration and are located in the bony labyrinth of the petrosal bone. Based on high-resolution computed tomography, we created a size-independent database of the bony labyrinth of 50 mammalian species especially rodents of the squirrel-related clade comprising taxa with fossorial, arboreal and gliding adaptations. Our sampling also includes gliding marsupials, actively flying bats, the arboreal tree shrew and subterranean species. The morphometric anatomy of the SCs was correlated to the locomotion mode. Even if the phylogenetic signal cannot entirely be excluded, the main significance for functional morphological studies has been found in the diameter of the SCs, whereas the radius of curvature is of minor interest. Additionally, we found clear differences in the bias angle of the canals between subterranean and gliding taxa, but also between sciurids and glirids. The sensitivity of the inner ear correlates with the locomotion mode, with a higher sensitivity of the SCs in fossorial species than in flying taxa. We conclude that the inner ear of flying and gliding mammals is less sensitive due to the large information flow into this sense organ during locomotion. PMID:26019162

  3. Multilocus phylogeny and cryptic diversity in Asian shrew-like moles (Uropsilus, Talpidae): implications for taxonomy and conservation

    PubMed Central

    2013-01-01

    Background The genus Uropsilus comprises a group of terrestrial, montane mammals endemic to the Hengduan and adjacent mountains. These animals are the most primitive living talpids. The taxonomy has been primarily based on cursory morphological comparisons and the evolutionary affinities are little known. To provide insight into the systematics of this group, we estimated the first multi-locus phylogeny and conducted species delimitation, including taxon sampling throughout their distribution range. Results We obtained two mitochondrial genes (~1, 985 bp) and eight nuclear genes (~4, 345 bp) from 56 specimens. Ten distinct evolutionary lineages were recovered from the three recognized species, eight of which were recognized as species/putative species. Five of these putative species were found to be masquerading as the gracile shrew mole. The divergence time estimation results indicated that climate change since the last Miocene and the uplift of the Himalayas may have resulted in the diversification and speciation of Uropsilus. Conclusions The cryptic diversity found in this study indicated that the number of species is strongly underestimated under the current taxonomy. Two synonyms of gracilis (atronates and nivatus) should be given full species status, and the taxonomic status of another three potential species should be evaluated using extensive taxon sampling, comprehensive morphological, and morphometric approaches. Consequently, the conservation status of Uropsilus spp. should also be re-evaluated, as most of the species/potential species have very limited distribution. PMID:24161152

  4. Distributions of vesicular glutamate transporters 1 and 2 in the visual system of tree shrews (Tupaia belangeri).

    PubMed

    Balaram, P; Isaamullah, M; Petry, H M; Bickford, M E; Kaas, J H

    2015-08-15

    Vesicular glutamate transporter (VGLUT) proteins regulate the storage and release of glutamate from synapses of excitatory neurons. Two isoforms, VGLUT1 and VGLUT2, are found in most glutamatergic projections across the mammalian visual system, and appear to differentially identify subsets of excitatory projections between visual structures. To expand current knowledge on the distribution of VGLUT isoforms in highly visual mammals, we examined the mRNA and protein expression patterns of VGLUT1 and VGLUT2 in the lateral geniculate nucleus (LGN), superior colliculus, pulvinar complex, and primary visual cortex (V1) in tree shrews (Tupaia belangeri), which are closely related to primates but classified as a separate order (Scandentia). We found that VGLUT1 was distributed in intrinsic and corticothalamic connections, whereas VGLUT2 was predominantly distributed in subcortical and thalamocortical connections. VGLUT1 and VGLUT2 were coexpressed in the LGN and in the pulvinar complex, as well as in restricted layers of V1, suggesting a greater heterogeneity in the range of efferent glutamatergic projections from these structures. These findings provide further evidence that VGLUT1 and VGLUT2 identify distinct populations of excitatory neurons in visual brain structures across mammals. Observed variations in individual projections may highlight the evolution of these connections through the mammalian lineage. PMID:25521420

  5. Lethal disease in infant and juvenile Syrian hamsters experimentally infected with Imjin virus, a newfound crocidurine shrew-borne hantavirus.

    PubMed

    Gu, Se Hun; Kim, Young-Sik; Baek, Luck Ju; Kurata, Takeshi; Yanagihara, Richard; Song, Jin-Won

    2015-12-01

    To gain insights into the pathogenicity of Imjin virus (MJNV), a newfound hantavirus isolated from the Ussuri white-toothed shrew (Crocidura lasiura), groups of Syrian hamsters (Mesocricetus auratus) of varying ages (<1, 5, 10, 14, 21, 35 and 56 days) were inoculated by the intraperitoneal route with 1000 pfu of MJNV strains 04-55 and 05-11. MJNV-infected Syrian hamsters, aged 21 days or less, exhibited reduced activity, weight loss, respiratory distress, hind-limb paralysis and seizures. Death ensued 1 to 6 days after onset of clinical disease. MJNV RNA was detected in brain and other major organs by RT-PCR and real time-PCR. Histopathological examination showed alveolar hemorrhage, interstitial pneumonia and severe pulmonary congestion; focal hepatic necrosis and portal inflammation; and acute meningoencephalitis. By immunohistochemistry, MJNV antigen was detected in pulmonary microvascular endothelial cells and glial cells. Older hamsters (35 and 56 days of age) developed subclinical infection without histopathological changes. Future studies are warranted to determine the pathophysiologic bases for the differential age susceptibility of Syrian hamsters to lethal MJNV disease. PMID:26371066

  6. The shrew tamed by Wolff's law: do functional constraints shape the skull through muscle and bone covariation?

    PubMed

    Cornette, Raphal; Tresset, Anne; Herrel, Anthony

    2015-03-01

    Bone is a highly plastic tissue that reflects the many potential sources of variation in shape. Here, we focus on the functional aspects of bone remodeling. We choose the skull for our analyses because it is a highly integrated system that plays a fundamental role in feeding and is thus, likely under strong natural selection. Its principal mechanical components are the bones and muscles that jointly produce bite force and jaw motion. Understanding the covariations among these three components is of interest to understand the processes driving the evolution of the feeding apparatus. In this study, we quantitatively and qualitatively compare interactions between these three components in shrews from populations known to differ in shape and bite force. Bite force was measured in the field using a force transducer and skull shape was quantified using surface geometric morphometric approaches based on CT-scans of the skulls of same individuals. The masseter, temporalis, pterygoideus, and digastricus muscles of these individuals were dissected and their cross sectional areas determined. Our results show strong correlations between bite force and muscle cross sectional areas as well as between bite force and skull shape. Moreover, bite force explains an important amount of skull shape variation. We conclude that interactions between bone shape and muscle characteristics can produce different morpho-functional patterns that may differ between populations and may provide a suitable target for selection to act upon. PMID:25385121

  7. Molecular evidence for the monophyly of tenrecidae (mammalia) and the timing of the colonization of Madagascar by Malagasy Tenrecs.

    PubMed

    Douady, Christophe J; Catzeflis, Francois; Kao, Diana J; Springer, Mark S; Stanhope, Michael J

    2002-03-01

    Tenrecs are a diverse family of insectivores, with an Afro-Malagasian biogeographic distribution. Three subfamilies (Geogalinae, Oryzorictinae, Tenrecinae) are restricted to Madagascar and one subfamily, the otter shrews (Potamogalinae), occurs on the mainland. Morphological studies have generated conflicting hypotheses according to which both tenrecids and Malagassy tenrecs are either monophyletic or paraphyletic. Competing hypotheses have different implications for the biogeographic history of Tenrecidae. At present, there are no molecular studies that address these hypotheses. The present study provides sequences of a nuclear protein-coding gene (vWF) and the mitochondrial 12S rRNA, tRNA valine, and 16S rRNA genes from a potamogaline (Micropotamogale). New sequences of these genes are also reported for the tenrecine, Tenrec ecaudatus. The 12S sequences from these taxa were combined with data already available for this locus from two other tenrecids (Echinops telfairi, subfamily Tenrecinae and Oryzorictes talpoides, subfamily Oryzorictinae). Phylogenetic analyses provided strong bootstrap support for the monophyly of Tenrecidae and Malagasy tenrecs. The majority of statistical tests rejected morphological claims for both a Tenrecinae--Chrysochloridae clade and an Oryzorictinae--Potamogalinae clade. Molecular clock estimates suggest a split of otter shrews and Malagasy tenrecs at approximately 53 MYA. We estimate that the ancestor of Malagasy tenrecs dispersed to Madagascar subsequent to this split but prior to about 37 MYA. PMID:11884160

  8. Rates of rewarming, heart and respiratory rates and their significance for oxygen transport during arousal from torpor in the smallest mammal, the Etruscan shrew Suncus etruscus.

    PubMed

    Fons, R; Sender, S; Peters, T; Jrgens, K D

    1997-05-01

    We investigated the process of rewarming from torpor with respect to respiratory and circulatory oxygen transport properties in the smallest mammal, the Etruscan shrew Suncus etruscus. In seven adult Etruscan shrews with a mean body mass of 2.4g, torpor was induced by deprivation of food and a cold environment. During arousal from torpor at an ambient temperature of 22 degrees C, the shrews actively rewarmed from the lowest mean (+/- S.D.) body temperature (Tb) of 12.1 +/- 1.2 degrees C to 20 degrees C at a rate of 0.43 +/- 0.14 degree C min-1, from 20 to 24 degrees C at a rate of 0.8 degree C min-1, and from 24 to 36 degrees C at a rate of 1.1 +/- 0.1 degrees C min-1. The mean rate from 12 degrees C to normothermia amounted to 0.83 degree C min-1, which is among the highest values recorded in mammals. During rewarming, the heart rate increased exponentially (Q10 = 2.2) from 100 to 800-1200 min-1, whereas the respiratory rate increased linearly from 50 to 600-800 min-1. These rates are higher than the heart and respiratory rates reported for other small mammals at the same Tb. The fraction of brown adipose tissue (BAT) was 9.2 +/- 1.6% of body mass, which is higher than in any other mammal. Up to a body temperature of approximately 17 degrees C, the heat for rewarming was mainly produced in the BAT; above this value, considerable activity of the skeletal muscles enhanced thermogenesis. Estimation of the mixed venous oxygen partial pressure showed that, at the tissue level, the rewarming process corresponds to heavy work conditions. The ventilatory system is adapted such that during rewarming, in addition to the appropriate oxygen transport capacity, there is also a capacity for hyperventilation. PMID:9192497

  9. ?9-Tetrahydrocannabinol Suppresses Vomiting Behavior and Fos Expression in Both Acute and Delayed Phases of Cisplatin-induced Emesis in the Least Shrew

    PubMed Central

    Ray, Andrew P.; Griggs, Lisa; Darmani, Nissar A.

    2008-01-01

    Cisplatin chemotherapy frequently causes severe vomiting in two temporally-separated clusters of bouts dubbed the acute and delayed phases. Cannabinoids can inhibit the acute phase, albeit through a poorly understood mechanism. We examined the substrates of cannabinoid-mediated inhibition of both emetic phases via immunolabeling for serotonin, Substance P, cannabinoid receptors 1 and 2 (CB1, CB2), and the neuronal activation marker Fos in the least shrew (Cryptotis parva). Shrews were injected with cisplatin (10 mg/kg ip), and one of vehicle, ?9-THC, or both ?9-THC and the CB1 receptor antagonist SR141716A (2 mg/kg ip), and monitored for vomiting. ?9-THC-pretreatment caused concurrent decreases in the number of shrews expressing vomiting and Fos-immunoreactivity (Fos-IR), effects which were blocked by SR141716A-pretreatment. Acute phase vomiting induced Fos-IR in the solitary tract nucleus (NTS), dorsal motor nucleus of the vagus (DMNX), and area postrema (AP), whereas in the delayed phase Fos-IR was not induced in the AP at all, and was induced at lower levels in the other nuclei when compared to the acute phase. CB1 receptor-IR in the NTS was dense, punctate labeling indicative of presynaptic elements, which surrounded Fos-expressing NTS neurons. CB2 receptor-IR was not found in neuronal elements, but in vascular-appearing structures. All areas correlated with serotonin- and Substance P-IR. These results support published acute phase data in other species, and are the first describing Fos-IR following delayed phase emesis. The data suggest overlapping but separate mechanisms are invoked for each phase, which are sensitive to antiemetic effects of ?9-THC mediated by CB1 receptors. PMID:18721829

  10. Delta 9-tetrahydrocannabinol suppresses vomiting behavior and Fos expression in both acute and delayed phases of cisplatin-induced emesis in the least shrew.

    PubMed

    Ray, Andrew P; Griggs, Lisa; Darmani, Nissar A

    2009-01-01

    Cisplatin chemotherapy frequently causes severe vomiting in two temporally separated clusters of bouts dubbed the acute and delayed phases. Cannabinoids can inhibit the acute phase, albeit through a poorly understood mechanism. We examined the substrates of cannabinoid-mediated inhibition of both the emetic phases via immunolabeling for serotonin, Substance P, cannabinoid receptors 1 and 2 (CB(1), CB(2)), and the neuronal activation marker Fos in the least shrew (Cryptotis parva). Shrews were injected with cisplatin (10mg/kg i.p.), and one of vehicle, Delta(9)-THC, or both Delta(9)-THC and the CB(1) receptor antagonist SR141716A (2mg/kg i.p.), and monitored for vomiting. Delta(9)-THC-pretreatment caused concurrent decreases in the number of shrews expressing vomiting and Fos-immunoreactivity (Fos-IR), effects which were blocked by SR141716A-pretreatment. Acute phase vomiting induced Fos-IR in the solitary tract nucleus (NTS), dorsal motor nucleus of the vagus (DMNX), and area postrema (AP), whereas in the delayed phase Fos-IR was not induced in the AP at all, and was induced at lower levels in the other nuclei when compared to the acute phase. CB(1) receptor-IR in the NTS was dense, punctate labeling indicative of presynaptic elements, which surrounded Fos-expressing NTS neurons. CB(2) receptor-IR was not found in neuronal elements, but in vascular-appearing structures. All areas correlated with serotonin- and Substance P-IR. These results support published acute phase data in other species, and are the first describing Fos-IR following delayed phase emesis. The data suggest overlapping but separate mechanisms are invoked for each phase, which are sensitive to antiemetic effects of Delta(9)-THC mediated by CB(1) receptors. PMID:18721829

  11. Interferon-Lambda3 (IFN-?3) and Its Cognate Receptor Subunits in Tree Shrews (Tupaia belangeri): Genomic Sequence Retrieval, Molecular Identification and Expression Analysis

    PubMed Central

    Li, Ming-Li; Xu, Wen-Wen; Gao, Yue-Dong; Guo, Yan; Wang, Wen-Ju; Wang, Chao; Jiang, Shi-You; Willden, Andrew; Huang, Jing-Fei; Zhang, Hua-Tang

    2013-01-01

    Type III IFNs (IFN-?s) constitute a new subfamily with antiviral activities by signaling through a unique receptor complex composed of IFN-?s receptor 1 (IFN?R1) and interleukin-10 receptor 2 (IL10R2). As tree shrews (Tupaia belangeri) have shown susceptiblility to several human viruses, they are a potentially important model for analyzing viral infection. However, little is known about their IFN-?s system. We used the tree shrew genome to retrieve IFN-?s and their receptor contig sequences by BLASTN and BLASTZ algorithms, and GenScan was used to scan transcripts from the putative contig sequences. RT-PCR and bioinformatic methods were then used to clone and characterize the IFN-?s system. Due to its highest identity with human IFN-?3, we opted to define one intact IFN-? gene, tsIFN-?3, as well as its two receptor subunits, tsIFN?R1 and tsIL10R2. Additionally, our results showed that tsIFN-?3 contained many features conserved in IFN-?3 genes from other mammals, including conserved signal peptide cleavage and glycosylation sites, and several residues responsible for binding to the type III IFNR. We also found six transcript variants in the receptors: three in tsIFN?R1, wherein different extracellular regions exist in three transmembrane proteins, resulting in different affinities with IFN-?s; and three more variants in tsIL10R2, encoding one transmembrane and two soluble proteins. Based on tissue distribution in the liver, heart, brain, lung, intestine, kidney, spleen, and stomach, we found that IFN-?s receptor complex was expressed in a variety of organs although the expression level differed markedly between them. As the first study to find transcript variants in IL-10R2, our study offers novel insights that may have important implications for the role of IFN-?s in tree shrews susceptibility with a variety of human viruses, bolstering the arguments for using tree shrews as an animal model in the study of human viral infections. PMID:23555878

  12. Transformation of Receptive Field Properties from Lateral Geniculate Nucleus to Superficial V1 in the Tree Shrew

    PubMed Central

    Roy, Arani; Rhodes, Heather J.; Culp, Julie H.; Fitzpatrick, David

    2013-01-01

    Tree shrew primary visual cortex (V1) exhibits a pronounced laminar segregation of inputs from different classes of relay neurons in the lateral geniculate nucleus (LGN). We examined how several receptive field (RF) properties were transformed from LGN to V1 layer 4 to V1 layer 2/3. The progression of RF properties across these stages differed markedly from that found in the cat. V1 layer 4 cells are largely similar to the the LGN cells that provide their input, being dominated by a single sign (ON or OFF) and being strongly modulated by sinusoidal gratings. Some layer 4 neurons, notably those near the edges of layer 4, exhibited increased orientation selectivity, and most layer 4 neurons exhibited a preference for lower temporal frequencies. Neurons in cortical layer 2/3 differ significantly from those in the LGN; most exhibited strong orientation tuning and both ON and OFF responses. The strength of orientation selectivity exhibited a notable sublaminar organization, with the strongest orientation tuned neurons in the most superficial parts of layer 2/3. Modulation indexes provide evidence for simple and complex cells in both layer 4 and layer 2/3. However, neurons with high modulation indexes were heterogenous in the spatial organization of ON and OFF responses, with many of them exhibiting unbalanced ON and OFF responses rather than well-segregated ON and OFF subunits. When compared to the laminar organization of V1 in other mammals, these data show that the process of natural selection can result in significantly altered structure/function relationships in homologous cortical circuits. PMID:23843520

  13. Identification of ghrelin in the house musk shrew (Suncus murinus): cDNA cloning, peptide purification and tissue distribution.

    PubMed

    Ishida, Yuko; Sakahara, Satoshi; Tsutsui, Chihiro; Kaiya, Hiroyuki; Sakata, Ichiro; Oda, Sen-Ichi; Sakai, Takafumi

    2009-05-01

    Ghrelin is the endogenous ligand for the growth hormone (GH) secretagogue receptor, and the sequence of ghrelin has been determined in many species from fish to mammals. In the present study, to reveal the production of ghrelin in the house musk shrew (Suncus murinus, order: Insectivora, suncus is used as a laboratory name), we determined the cDNA sequence and structure of suncus ghrelin and also demonstrated the ghrelin-producing cells in the gastrointestinal tract. Results of cDNA cloning and mass spectrometry analysis revealed that suncus ghrelin is composed of 18 or 26 amino acid residues and that the 3rd Ser was acylated mainly by n-octanoic acid. The 10 amino acids of the N-terminal region of suncus mature ghrelin were consistent with those of other mammals. Quantitative RT-PCR revealed that suncus ghrelin mRNA is highly expressed in the gastric corpus and pyloric antrum, and low expression levels were found in various tissues, including the intestinal tract. Ghrelin cells were found only in the corpus and antrum by immunohistochemistry and in situ hybridization, and most of the ghrelin cells were closed-type cells with relatively rich cytoplasm and scattered in the glandular body and base of the gastric mucosa. The density of ghrelin cells in the corpus was significantly greater than that in the antrum. The results of this study together with our recent results regarding motilin production in the suncus indicate that the suncus will be a useful model animal for study of physiological function of the motilin/ghrelin family. PMID:19428777

  14. Thalamic burst firing propensity: a comparison of the dorsal lateral geniculate and pulvinar nuclei in the tree shrew.

    PubMed

    Wei, Haiyang; Bonjean, Maxime; Petry, Heywood M; Sejnowski, Terrence J; Bickford, Martha E

    2011-11-23

    Relay neurons in dorsal thalamic nuclei can fire high-frequency bursts of action potentials that ride the crest of voltage-dependent transient (T-type) calcium currents [low-threshold spike (LTS)]. To explore potential nucleus-specific burst features, we compared the membrane properties of dorsal lateral geniculate nucleus (dLGN) and pulvinar nucleus relay neurons using in vitro whole-cell recording in juvenile and adult tree shrew (Tupaia) tissue slices. We injected current ramps of variable slope into neurons that were sufficiently hyperpolarized to de-inactivate T-type calcium channels. In a small percentage of juvenile pulvinar and dLGN neurons, an LTS could not be evoked. In the remaining juvenile neurons and in all adult dLGN neurons, a single LTS could be evoked by current ramps. However, in the adult pulvinar, current ramps evoked multiple LTSs in >70% of recorded neurons. Using immunohistochemistry, Western blot techniques, unbiased stereology, and confocal and electron microscopy, we found that pulvinar neurons expressed more T-type calcium channels (Ca(v) 3.2) and more small conductance potassium channels (SK2) than dLGN neurons and that the pulvinar nucleus contained a higher glia-to-neuron ratio than the dLGN. Hodgkin-Huxley-type compartmental models revealed that the distinct firing modes could be replicated by manipulating T-type calcium and SK2 channel density, distribution, and kinetics. The intrinsic properties of pulvinar neurons that promote burst firing in the adult may be relevant to the treatment of conditions that involve the adult onset of aberrant thalamocortical interactions. PMID:22114295

  15. Cisplatin increases brain 2-arachidonoylglycerol (2-AG) and concomitantly reduces intestinal 2-AG and anandamide levels in the least shrew.

    PubMed

    Darmani, Nissar A; McClanahan, Bryan A; Trinh, Chung; Petrosino, Stefania; Valenti, Marta; Di Marzo, Vincenzo

    2005-09-01

    The chemotherapeutic agent cisplatin may produce emesis via release of several neurotransmitters such as serotonin (5-HT), substance P and/or dopamine as well as production of prostaglandins (PGs). Administration of synthetic 2-arachidonoylglycerol (2-AG) but not of anandamide, which are two putative endocannabinoids, causes vomiting via its downstream metabolites such as arachidonic acid (AA) and PGs in the least shrew (Cryptotis parva). We report here that cisplatin (0, 5, 10 and 20 mg/kg, i.p.) causes dose- and time-dependent increases in brain tissue levels of 2-AG but not anandamide in this vomiting species. Concomitantly, intestinal tissue levels of both endocannabinoids are relatively reduced. Selective inhibitors [arachidonoyl-serotonin (AA-5-HT) and URB597, 0-5 and 0-10 mg/kg, i.p.] of one of the major endocannabinoid metabolic enzymes, the intracellular fatty acid amide hydrolase (FAAH), do not significantly prevent vomiting produced by emetic doses of i.p.-administered 2-AG, cisplatin or the dopamine receptor agonist apomorphine. At large doses (10 and 20 mg/kg, respectively), both FAAH inhibitors caused emesis per se. Administration of one selective uptake inhibitor of endocannabinoids, OMDM1 (0-5 mg/kg, i.p.), also did not significantly prevent emesis by the direct and indirect emetic stimuli, and likewise caused emesis by itself at a high (10 mg/kg) dose. However, another selective uptake inhibitor, VDM11, did not produce significant emesis per se and prevented emesis caused by apomorphine. Both the corticosteroid dexamethasone, and the cyclooxygenase inhibitor indomethacin, reduced vomiting produced by cisplatin. These data: (a) provide the first evidence that cisplatin causes a selective increase in 2-AG levels in the brain, and (b) support the established notion that 2-AG may produce some of its effects, including emesis, via downstream metabolites produced independently of FAAH. PMID:15921709

  16. Synergistic antiemetic interactions between serotonergic 5-HT3 and tachykininergic NK1-receptor antagonists in the least shrew (Cryptotis parva).

    PubMed

    Darmani, Nissar A; Chebolu, Seetha; Amos, Barry; Alkam, Tursun

    2011-10-01

    Significant electrophysiological and biochemical findings suggest that receptor cross-talk occurs between serotonergic 5-HT(3)- and tachykininergic NK(1)-receptors in which co-activation of either receptor by ineffective doses of their corresponding agonists (serotonin (5-HT) or substance P (SP), respectively) potentiates the activity of the other receptor to produce a response. In contrast, selective blockade of any one of these receptors attenuates the increase in abdominal vagal afferent activity caused by either 5-HT or SP. This interaction has important implications in chemotherapy-induced nausea and vomiting (CINV) since 5-HT(3)- and NK(1)-receptor antagonists are the major classes of antiemetics used in cancer patients receiving chemotherapy. The purpose of this study was to demonstrate whether the discussed interaction produces effects at the behavioral level in a vomit-competent species, the least shrew. Our results demonstrate that pretreatment with either a 5-HT(3) (tropisetron)- or an NK(1) (CP99,994)-receptor specific antagonist, attenuates vomiting caused by a selective agonist (2-methyl 5-HT or GR73632, respectively) of both emetic receptors. In addition, relative to each antagonist alone, their combined doses were 4-20 times more potent against vomiting caused by each emetogen. Moreover, combined sub-maximal doses of the agonists 2-methyl 5-HT and GR73632, produced 8-12 times greater number of vomits relative to each emetogen tested alone. However, due to large variability in vomiting caused by the combination doses, the differences failed to attain significance. The antiemetic dose-response curves of tropisetron against both emetogens were U-shaped probably because larger doses of this antagonist behave as a partial agonist. The data demonstrate that 5-HT(3)- and NK(1)-receptors cross-talk to produce vomiting, and that synergistic antiemetic effects occur when both corresponding antagonists are concurrently used against emesis caused by each specific emetogen. PMID:21683089

  17. Dasypodidae Borner, 1919 (Insecta, Hymenoptera): Proposed emendation of spelling to Dasypodaidae, so removing the homonymy with Dasypodidae Gray, 1821 (Mammalia, Xenarthra)

    USGS Publications Warehouse

    Alexander, B.A.; Michener, C.D.; Gardner, A.L.

    1998-01-01

    The family-group name DASYPODIDAE Borner, 1919 (Insecta, Hymenoptera) is a junior homonym Of DASYPODIDAE Gray, 1821 (Mammalia, Xenarthra). It is proposed that the homonymy between the two names, which relate to short-tongued bees and armadillos respectively, should be removed by emending the stem of the generic name Dasypoda Latreille, 1802, on which the insect familygroup name is based, to give DASYPODAIDAE, while leaving the mammalian name (based on Dasypus Linnaeus, 1758) unchanged. Dasypus novemcinctus Linnaeus, 1758, the type species of Dasypus, has a wide distribution in the southern United States, Central and South America. The genus Dasypoda ranges throughout most of the Palearctic region.

  18. Inference in a social context: A comparative study of capuchin monkeys (Cebus apella), tree shrews (Tupaia belangeri), hamsters (Mesocricetus auratus), and rats (Rattus norvegicus).

    PubMed

    Takahashi, Makoto; Ueno, Yoshikazu; Fujita, Kazuo

    2015-11-01

    Four species (capuchin monkeys, tree shrews, rats, and hamsters) performed an inference task situated in a social context. In Experiment 1, capuchin monkeys first explored food sites under 1 of 2 conditions: In 1 condition, food was refilled after it was eaten (replenished condition), whereas it was not refilled (depleted condition) in the other condition. Two food sites were presented for each condition. In the test phase, a subject watched a conspecific demonstrator visit 1 of the food sites in either the replenished or depleted condition. A screen placed in front of the sites prevented the subject from seeing the demonstrator actually eat the food. When the demonstrator was removed, the subject explored the cage. Three of 4 monkeys tended to go to the unvisited sites in the depleted condition, but tended to go to the visited site in the replenished condition. This suggests that they inferred that there was no food because the demonstrator had eaten it. In Experiment 2, using the same procedure, 2 nongroup-living species (tree shrews and hamsters) were indifferent to demonstrator behavior and visited sites only randomly, and group-living rats showed a strong tendency to follow demonstrators, irrespective of the type of food site. These tendencies were unchanged when olfactory information was added in Experiment 3 and when motivation to compete increased in Experiment 4. These results suggest that only capuchin monkeys have the ability to solve an inference task when cued by social information. (PsycINFO Database Record PMID:26460855

  19. Measuring airborne components of seismic body vibrations in a Middle-Asian sand-dwelling Insectivora species, the piebald shrew (Diplomesodon pulchellum).

    PubMed

    Volodin, Ilya A; Zaytseva, Alexandra S; Ilchenko, Olga G; Volodina, Elena V; Chebotareva, Anastasia L

    2012-08-15

    Self-produced seismic vibrations have been found for some subterranean rodents but have not been reported for any Insectivora species, although seismic sensitivity has been confirmed for blind sand-dwelling chrysochlorid golden moles. Studying the vocal behaviour of captive piebald shrews, Diplomesodon pulchellum, we documented vibrations, apparently generated by the whole-body wall muscles, from 11 (5 male, 6 female) of 19 animals, placed singly on a drum membrane. The airborne waves of the vibratory drumming were digitally recorded and then analysed spectrographically. The mean frequency of vibration was 160.5 Hz. This frequency matched the periodicity of the deep sinusoidal frequency modulation (159.4 Hz) found in loud screech calls of the same subjects. The body vibration was not related to thermoregulation, hunger-related depletion of energy resources or fear, as it was produced by well-fed, calm animals, at warm ambient temperatures. We hypothesize that in the solitary, nocturnal, digging desert piebald shrew, body vibrations may be used for seismic exploration of substrate density, to avoid energy-costly digging of packed sand for burrowing and foraging. At the same time, the piercing quality of screech calls due to the deep sinusoidal frequency modulation, matching the periodicity of body vibration, may be important for agonistic communication in this species. PMID:22837458

  20. Ecological risk assessment for mink and short-tailed shrew exposed to PCBs, dioxins, and furans in the Housatonic River area.

    PubMed

    Moore, Dwayne Rj; Breton, Roger L; DeLong, Tod R; Ferson, Scott; Lortie, John P; MacDonald, Drew B; McGrath, Richard; Pawlisz, Andrzej; Svirsky, Susan C; Teed, R Scott; Thompson, Ryan P; Whitfield Aslund, Melissa

    2016-01-01

    A probabilistic risk assessment was conducted to characterize risks to a representative piscivorous mammal (mink, Mustela vison) and a representative carnivorous mammal (short-tailed shrew, Blarina brevicauda) exposed to PCBs, dioxins, and furans in the Housatonic River area downstream of the General Electric (GE) facility in Pittsfield, Massachusetts. Contaminant exposure was estimated using a probabilistic total daily intake model and parameterized using life history information of each species and concentrations of PCBs, dioxins, and furans in prey collected in the Housatonic River study area. The effects assessment preferentially relied on dose-response curves but defaulted to benchmarks or other estimates of effect when there were insufficient toxicity data. The risk characterization used a weight of evidence approach. Up to 3 lines of evidence were used to estimate risks to the selected mammal species: 1) probabilistic exposure and effects modeling, 2) field surveys, and 3) species-specific feeding or field studies. The weight of evidence assessment indicated a high risk for mink and an intermediate risk for short-tailed shrew. Integr Environ Assess Manag 2016;12:174-184. 2015 SETAC. PMID:25976918

  1. Cloning of putative uncoupling protein 1 cDNA in a cold-intolerant mammal, the house musk shrew (Suncus murinus).

    PubMed

    Suzuki, Daisuke; Murata, Yoshiharu; Oda, Sen-ichi

    2006-11-01

    The house musk shrew (Suncus murinus), or suncus, is a unique experimental animal. We recently showed that this mammal is cold intolerant and hypothesized that its sensitivity to cold is caused by low thermogenic activity in brown adipose tissue (BAT). Thermogenesis in BAT is performed by a unique mitochondrial protein, uncoupling protein 1 (UCP1). Interestingly, only eutherians possess UCP1, and some traits in the suncus resemble those in the Ucp1-ablated mouse, including cold intolerance, histology of BAT, and obesity resistance. In a previous study, we hypothesized that UCP1 may not be present in BAT of the suncus or may be dysfunctional. Therefore, we performed cDNA cloning of suncus Ucp1 and compared it to homologs from other species. The deduced amino acid sequence showed high similarity to other mammalian UCP1. Northern blot analysis revealed mRNA in BAT, as in other mammals. However, a difference in an amino acid residue was observed in an important residue for thermogenesis. Genomic sequence analysis showed that this difference existed in our two genetically distant laboratory colonies. These results suggest that cold intolerance in the suncus is derived from low thermogenic activity of UCP1 and may exist in wild house musk shrews. PMID:17189913

  2. The Sahara as a vicariant agent, and the role of Miocene climatic events, in the diversification of the mammalian order Macroscelidea (elephant shrews).

    PubMed

    Douady, Christophe J; Catzeflis, Franois; Raman, Jaishree; Springer, Mark S; Stanhope, Michael J

    2003-07-01

    Although the Sahara is a major geographical feature of the African continent, its role in the diversification of animal species is not well understood. We present here a molecular phylogeny for members of the endemic African mammalian order Macroscelidea (elephant shrews) with molecular-clock calculations; this molecular phylogeny provides convincing evidence that the genus Elephantulus is diphyletic. Elephantulus rozeti, the only elephant shrew species that resides north of the Sahara, is the sister group of a species from a different genus (Petrodromus tetradactylus), which resides just south of the Sahara. The split between these taxa coincided with major Miocene climatic events, which triggered the cooling and aridification of midlatitude continental regions, and a shift in the Sahara from a tropical to an arid environment. Thus, the North African distribution of E. rozeti is not the result of dispersion from an eastern species of the genus, but instead the result of a vicariant event involving the formation of the Sahara. The splitting events involved with most Elephantulus species in our analysis appear to coincide with these climatic events. This coincidence suggests that the environmental consequences associated with this period played an important role in the radiation of this order of mammals. The strongly supported phylogeny provides compelling evidence for a complex history of mosaic evolution, including pronounced bradytelic morphological evolution in some lineages, accelerated morphological evolution in others, and a remarkably slow rate of evolution of the male reproductive structure. PMID:12821774

  3. Receptor-selective agonists induce emesis and Fos expression in the brain and enteric nervous system of the least shrew (Cryptotis parva).

    PubMed

    Ray, Andrew P; Chebolu, Seetha; Darmani, Nissar A

    2009-11-01

    Research on the mechanisms of emesis has implicated multiple neurotransmitters via both central (dorsal vagal complex) and peripheral (enteric neurons and enterochromaffin cells) anatomical substrates. Taking advantage of advances in receptor-specific agonists, and utilizing Fos expression as a functional activity marker, this study demonstrates a strong, but incomplete, overlap in anatomical substrates for a variety of emetogens. We used cisplatin and specific agonists to 5-HT(3) serotonergic, D(2)/D(3) dopaminergic, and NK(1) tachykininergic receptors to induce vomiting in the least shrew (Cryptotis parva), and quantified the resulting Fos expression. The least shrew is a small mammal whose responses to emetic challenges are very similar to its human counterparts. In all cases, the enteric nervous system, nucleus of the solitary tract, and dorsal motor nucleus of the vagus demonstrated significantly increased Fos immunoreactivity (Fos-IR). However, Fos-IR induction was notably absent from the area postrema following the dopaminergic and NK(1) receptor-specific agents. Two brain nuclei not usually discussed regarding emesis, the dorsal raphe nucleus and paraventricular thalamic nucleus, also demonstrated increased emesis-related Fos-IR. Taken together, these data suggest the dorsal vagal complex is part of a common pathway for a variety of distinct emetogens, but there are central emetic substrates, both medullary and diencephalic, that can be accessed without directly stimulating the area postrema. PMID:19699757

  4. Receptor-Selective Agonists Induce Emesis and Fos Expression in the Brain and Enteric Nervous System of the Least Shrew (Cryptotis parva)

    PubMed Central

    Ray, Andrew P.; Chebolu, Seetha; Darmani, Nissar A.

    2009-01-01

    Research on the mechanisms of emesis has implicated multiple neurotransmitters via both central (dorsal vagal complex) and peripheral (enteric neurons and enterochromaffin cells) anatomical substrates. Taking advantage of advances in receptor-specific agonists, and utilizing Fos expression as a functional activity marker, this study demonstrates a strong, but incomplete, overlap in anatomical substrates for a variety of emetogens. We used cisplatin and specific agonists to 5-HT3 serotonergic, D2/D3 dopaminergic, and NK1 tachykininergic receptors to induce vomiting in the least shrew (Cryptotis parva), and quantified the resulting Fos expression. The least shrew is a small mammal whose responses to emetic challenges are very similar to its human counterparts. In all cases, the enteric nervous system, nucleus of the solitary tract, and dorsal motor nucleus of the vagus demonstrated significantly increased Fos immunoreactivity (Fos-IR). However, Fos-IR induction was notably absent from the area postrema following the dopaminergic and NK1 receptor-specific agents. Two brain nuclei not usually discussed regarding emesis, the dorsal raphe nucleus and paraventricular thalamic nucleus, also demonstrated increased emesis-related Fos-IR. Taken together, these data suggest the dorsal vagal complex is part of a common pathway for a variety of distinct emetogens, but there are central emetic substrates, both medullary and diencephalic, that can be accessed without directly stimulating the area postrema. PMID:19699757

  5. Mediterranean populations of the lesser white-toothed shrew (Crocidura suaveolens group): an unexpected puzzle of Pleistocene survivors and prehistoric introductions.

    PubMed

    Dubey, S; Cosson, J-F; Magnanou, E; Vohralík, V; Benda, P; Frynta, D; Hutterer, R; Vogel, V; Vogel, P

    2007-08-01

    An earlier study revealed the strong phylogeographical structure of the lesser white-toothed shrew (Crocidura suaveolens group) within the northern Palaearctic. Here, we aim to reconstruct the colonization history of Mediterranean islands and to clarify the biogeography and phylogeographical relationships of the poorly documented Middle East region with the northern Palaearctic. We performed analyses on 998-bp-long haplotypes of the mitochondrial cytochrome b gene of 143 samples collected around the Mediterranean basin, including islands and the Middle East. The analyses suggest that the Cypriot shrew belongs to the rare group of relict insular Pleistocene mammal taxa that have survived to the present day. In contrast, the Cretan, Corsican and Menorcan populations were independently introduced from the Middle East during the Holocene. The phylogeographical structure of this temperate Palaearctic species within the Middle East appears to be complex and rich in diversity, probably reflecting fragmentation of the area by numerous mountain chains. Four deeply divergent clades of the C. suaveolens group occur in the area, meaning that a hypothetical contact zone remains to be located in central western Iran. PMID:17688544

  6. UTILIZATION OF THE LEAST SHREW AS A RAPID AND SELECTIVE SCREENING MODEL FOR THE ANTIEMETIC POTENTIAL AND BRAIN PENETRATION OF SUBSTANCE P AND NK1 RECEPTOR ANTAGONISTS

    PubMed Central

    Darmani, Nissar A.; Wang, Yaozhi; Abad, Joseph; Ray, Andrew P.; Thrush, Gerald R.; Ramirez, Juan

    2008-01-01

    Substance P (SP) is thought to play a cardinal role in emesis via the activation of central tachykinin NK1 receptors during the delayed phase of vomiting produced by chemotherapeutics. Although the existing supportive evidence is significant, due to lack of an appropriate animal model, the evidence is indirect. As yet, no study has confirmed that emesis produced by SP or a selective NK1 receptor agonist is sensitive to brain penetrating antagonists of either NK1, NK2, or NK3 receptors. The goals of this investigation were to demonstrate: 1) whether intraperitoneal (i.p.) administration of either SP, a brain penetrating (GR73632) or non-penetrating (e.g. SarMet SP) NK1 receptor agonist, an NK2 receptor agonist (GR64349), or an NK3 receptor agonist (Pro7-NKB), would induce vomiting and/or scratching in the least shrew (Cryptotis parva) in a dose-dependent manner; and whether these effects are sensitive to the above selective receptor antagonists; 2) whether an exogenous emetic dose of SP (50 mg/kg, i.p.) can penetrate into the shrew brain stem and frontal cortex; 3) whether GR73632 (2.5 mg/kg, i.p.)-induced activation of NK1 receptors increases Fos-measured neuronal activity in the neurons of both brain stem emetic nuclei and the enteric nervous system of the gut; and 4) whether selective ablation of peripheral NK1 receptors can affect emesis produced by GR73632. The results clearly demonstrated that while SP produced vomiting only, GR73632 caused both emesis and scratching behavior dose-dependently in shrews, and these effects were sensitive to NK1-, but not NK2- or NK3-receptor antagonists. Neither the selective, non-penetrating NK1 receptor agonists, nor the selective NK2- or NK3-receptor agonists, caused a significant dose-dependent behavioral effect. An emetic dose of SP selectively and rapidly penetrated the brain stem but not the frontal cortex. Systemic GR73632 increased Fos expression in the enteric nerve plexi, the medial subnucleus of nucleus tractus solitarius, and the dorsal motor nucleus of the vagus, but not the area postrema. Ablation of peripheral NK1 receptors attenuated the ability of GR73632 to induce a maximal frequency of emesis and shifted its percent animals vomiting dose-response curve to the right. The NK1-ablated shrews exhibited scratching behavior after systemic GR73632-injection. These results, for the first time, affirm a cardinal role for central NK1 receptors in SP-induced vomiting, and a facilitatory role for gastrointestinal NK1 receptors. In addition, these data support the validation of the least shrew as a specific and rapid behavioral animal model to screen concomitantly both the CNS penetration and the antiemetic potential of tachykinin NK1 receptor antagonists. PMID:18471804

  7. Utilization of the least shrew as a rapid and selective screening model for the antiemetic potential and brain penetration of substance P and NK1 receptor antagonists.

    PubMed

    Darmani, Nissar A; Wang, Yaozhi; Abad, Joseph; Ray, Andrew P; Thrush, Gerald R; Ramirez, Juan

    2008-06-12

    Substance P (SP) is thought to play a cardinal role in emesis via the activation of central tachykinin NK1 receptors during the delayed phase of vomiting produced by chemotherapeutics. Although the existing supportive evidence is significant, due to lack of an appropriate animal model, the evidence is indirect. As yet, no study has confirmed that emesis produced by SP or a selective NK1 receptor agonist is sensitive to brain penetrating antagonists of either NK1, NK2, or NK3 receptors. The goals of this investigation were to demonstrate: 1) whether intraperitoneal (i.p.) administration of either SP, a brain penetrating (GR73632) or non-penetrating (e.g. SarMet-SP) NK1 receptor agonist, an NK2 receptor agonist (GR64349), or an NK3 receptor agonist (Pro7-NKB), would induce vomiting and/or scratching in the least shrew (Cryptotis parva) in a dose-dependent manner; and whether these effects are sensitive to the above selective receptor antagonists; 2) whether an exogenous emetic dose of SP (50 mg/kg, i.p.) can penetrate into the shrew brain stem and frontal cortex; 3) whether GR73632 (2.5 mg/kg, i.p.)-induced activation of NK1 receptors increases Fos-measured neuronal activity in the neurons of both brain stem emetic nuclei and the enteric nervous system of the gut; and 4) whether selective ablation of peripheral NK1 receptors can affect emesis produced by GR73632. The results clearly demonstrated that while SP produced vomiting only, GR73632 caused both emesis and scratching behavior dose-dependently in shrews, and these effects were sensitive to NK1-, but not NK2- or NK3-receptor antagonists. Neither the selective, non-penetrating NK1 receptor agonists, nor the selective NK2- or NK3-receptor agonists, caused a significant dose-dependent behavioral effect. An emetic dose of SP selectively and rapidly penetrated the brain stem but not the frontal cortex. Systemic GR73632 increased Fos expression in the enteric nerve plexi, the medial subnucleus of nucleus tractus solitarius, and the dorsal motor nucleus of the vagus, but not the area postrema. Ablation of peripheral NK1 receptors attenuated the ability of GR73632 to induce a maximal frequency of emesis and shifted its percent animals vomiting dose-response curve to the right. The NK1-ablated shrews exhibited scratching behavior after systemic GR73632-injection. These results, for the first time, affirm a cardinal role for central NK1 receptors in SP-induced vomiting, and a facilitatory role for gastrointestinal NK1 receptors. In addition, these data support the validation of the least shrew as a specific and rapid behavioral animal model to screen concomitantly both the CNS penetration and the antiemetic potential of tachykinin NK1 receptor antagonists. PMID:18471804

  8. A mongoose remain (Mammalia: Carnivora) from the Upper Irrawaddy sediments, Myanmar and its significance in evolutionary history of Asian herpestids

    NASA Astrophysics Data System (ADS)

    Egi, Naoko; Thaung-Htike; Zin-Maung-Maung-Thein; Maung-Maung; Nishioka, Yuichiro; Tsubamoto, Takehisa; Ogino, Shintaro; Takai, Masanaru

    2011-11-01

    A tooth of a mongoose (Mammalia: Carnivora: Herpestidae) was discovered from the Upper Irrawaddy sediments in central Myanmar. The age of the fauna is not older than the mid-Pliocene. It is identified as a right first upper molar of a small species of Urva (formally included in the genus Herpestes) based on its size and shape. The present specimen is the first carnivoran from the Upper Irrawaddy sediments and is the first record of mongooses in the Pliocene and early Pleistocene of Asia. It confirms that mongooses had already dispersed into Southeast Asia by the late Pliocene, being consistent with the previous molecular phylogenetic analyses. The fossil may belong to one of the extant species, but an assignment to a specific species is difficult due to the fragmentary nature of the specimen and the small interspecific differences in dental shape among the Asian mongooses. The size of the tooth suggests that the Irrawaddy specimen is within or close to the clade of Urva auropunctata + javanica + edwardsii, and this taxonomic assignment agrees with the geographical distribution.

  9. Delta-9-tetrahydrocannabinol differentially suppresses cisplatin-induced emesis and indices of motor function via cannabinoid CB(1) receptors in the least shrew.

    PubMed

    Darmani, N A

    2001-01-01

    We have recently shown that the cannabinoid CB(1) receptor antagonist, SR 141716A, produces emesis in the least shrew (Cryptotis parva) in a dose- and route-dependent manner. This effect was blocked by delta-9-tetrahydrocannabinol (Delta(9)-THC). The present study investigates the cannabinoid receptor mechanisms by which Delta(9)-THC produces its antiemetic effects against cisplatin (20 mg/kg, i.p.)-induced emesis as well as its cannabimimetic activity profile (motor reduction) in the least shrew. Intraperitoneal administration of Delta(9)-THC (1, 2.5, 5 and 10 mg/kg) dose-dependently reduced both the percentage of animals vomiting (ID(50)=1.8+/-1.6 mg/kg) and the frequency of vomits (ID(50)=0.36+/-1.18 mg/kg) in a potent manner. The lowest significantly effective antiemetic dose of Delta(9)-THC for the latter emesis parameters was 2.5 mg/kg. Although Delta(9)-THC reduced the frequency of vomits up to 98%, it failed to completely protect all tested shrews from vomiting (80% protection). The cannabinoid CB(1) antagonist (SR 141716A) and not the CB(2) antagonist (SR 144528), reversed the antiemetic effects of Delta(9)-THC in a dose-dependent fashion. Delta(9)-THC (1, 5, 10 and 20 mg/kg, ip) suppressed locomotor parameters (spontaneous locomotor activity, duration of movement and rearing frequency) in a biphasic manner and only the 20-mg/kg dose simultaneously suppressed the triad of locomotor parameters to a significant degree. Subcutaneous (1-10 mg/kg) and intraperitoneal (0.05-40 mg/kg) injection of some doses of SR 141716A caused significant reductions in one or more components of the triad of locomotor parameters but these reductions were not dose dependent. Subcutaneous injection of SR 141716A (0.2, 1, 5 and 10 mg/kg) reversed the motor suppressant effects of a 20-mg/kg dose of Delta(9)-THC (ip) in a dose-dependent manner. Relative to its motor suppressant effects, Delta(9)-THC is a more potent antiemetic agent. Both effects are probably mediated via CB(1) receptors in distinct loci. PMID:11420092

  10. Binocular Lens Treatment in Tree Shrews: Effect of Age and Comparison of Plus Lens Wear with Recovery from Minus Lens-induced Myopia

    PubMed Central

    Siegwart, John T.; Norton, Thomas T.

    2010-01-01

    We examined normal emmetropization and the refractive responses to binocular plus or minus lenses in young (late infantile) and juvenile tree shrews. In addition, recovery from lens-induced myopia was compared with the response to a similar amount of myopia produced with plus lenses in age-matched juvenile animals. Normal emmetropization was examined with daily noncycloplegic autorefractor measures from 11 days after natural eye-opening (days of visual experience [VE]) when the eyes were in the infantile, rapid growth phase and their refractions were substantially hyperopic, to 35 days of VE when the eyes had entered the juvenile, slower growth phase and the refractions were near emmetropia. Starting at 11 days of VE, two groups of young tree shrews wore binocular +4 D lenses (n = 6) or ?5 D lenses (n = 5). Starting at 24 days of VE, four groups of juvenile tree shrews (n = 5 each) wore binocular +3 D, +5 D, ?3 D, or ?5 D lenses. Non-cycloplegic measures of refractive state were made frequently while the animals wore the assigned lenses. The refractive response of the juvenile plus-lens wearing animals was compared with the refractive recovery of an age-matched group of animals (n=5) that were myopic after wearing a ?5 D lens from 11 to 24 days of VE. In normal tree shrews, refractions (corrected for the small eye artifact) declined rapidly from (mean SEM) 6.6 0.6 D of hyperopia at 11 VE to 1.4 0.2 D at 24 VE and 0.8 0.4 D at 35 VE. Plus 4 D lens treatment applied at 11 days of VE initially corrected or over-corrected the young animals hyperopia and produced a compensatory response in most animals; the eyes became nearly emmetropic while wearing the +4 D lenses. In contrast, plus-lens treatment starting at 24 days of VE initially made the juvenile eyes myopic (over-correction) and, on average, was less effective. The response ranged from no change in refractive state (eye continued to experience myopia) to full compensation (emmetropic with the lens in place). Minus-lens wear in both the young and juvenile groups, which initially made eyes more hyperopic, consistently produced compensation to the minus lens so that eyes reached age-appropriate refractions while wearing the lenses. When the minus lenses were removed, the eyes recovered quickly to age-matched normal values. The consistent recovery response from myopia in juvenile eyes after minus-lens compensation, compared with the highly variable response to plus lens wear in age-matched juvenile animals suggests that eyes retain the ability to detect the myopic refractive state, but there is an age-related decrease in the ability of normal eyes to use myopia to slow their elongation rate below normal. If juvenile human eyes, compared with infants, have a similar difficulty in using myopia to slow axial elongation, this may contribute to myopia development, especially in eyes with a genetic pre-disposition to elongate. PMID:20713041

  11. Decay of Ca2+ and force transients in fast- and slow-twitch skeletal muscles from the rat, mouse and Etruscan shrew.

    PubMed

    Wetzel, P; Gros, G

    1998-02-01

    Isometric single-twitch force and intracellular Ca2+ transients were recorded simultaneously, using fura-2, from slow- and fast-twitch muscle fibres of the rat, mouse and Etruscan shrew Suncus etruscus. In the slow-twitch rat soleus, force half-relaxation time was three times longer than the 50% decay time of the fura-2 signal. In contrast, in the fast-twitch extensor digitorum longus muscles of all three animals, muscle relaxation preceded Ca2+ decay. It is proposed that this surprising property of fast-twitch muscles is due to their pCa-tension curve, which is shifted to the right compared with that of slow-twitch muscle. PMID:9503643

  12. Decay of Ca2+ and force transients in fast- and slow-twitch skeletal muscles from the rat, mouse and Etruscan shrew.

    PubMed

    Wetzel; g

    1998-01-01

    Isometric single-twitch force and intracellular Ca2+ transients were recorded simultaneously, using fura-2, from slow- and fast-twitch muscle fibres of the rat, mouse and Etruscan shrew Suncus etruscus. In the slow-twitch rat soleus, force half-relaxation time was three times longer than the 50 % decay time of the fura-2 signal. In contrast, in the fast-twitch extensor digitorum longus muscles of all three animals, muscle relaxation preceded Ca2+ decay. It is proposed that this surprising property of fast-twitch muscles is due to their pCatension curve, which is shifted to the right compared with that of slow-twitch muscle. PMID:9427671

  13. Diet is a major factor governing the fecal butyrate-producing community structure across Mammalia, Aves and Reptilia.

    PubMed

    Vital, Marius; Gao, Jiarong; Rizzo, Mike; Harrison, Tara; Tiedje, James M

    2015-04-01

    Butyrate-producing bacteria have an important role in maintaining host health. They are well studied in human and medically associated animal models; however, much less is known for other Vertebrata. We investigated the butyrate-producing community in hindgut-fermenting Mammalia (n = 38), Aves (n = 8) and Reptilia (n = 8) using a gene-targeted pyrosequencing approach of the terminal genes of the main butyrate-synthesis pathways, namely butyryl-CoA:acetate CoA-transferase (but) and butyrate kinase (buk). Most animals exhibit high gene abundances, and clear diet-specific signatures were detected with but genes significantly enriched in omnivores and herbivores compared with carnivores. But dominated the butyrate-producing community in these two groups, whereas buk was more abundant in many carnivorous animals. Clustering of protein sequences (5% cutoff) of the combined communities (but and buk) placed carnivores apart from other diet groups, except for noncarnivorous Carnivora, which clustered together with carnivores. The majority of clusters (but: 5141 and buk: 2924) did not show close relation to any reference sequences from public databases (identity <90%) demonstrating a large 'unknown diversity'. Each diet group had abundant signature taxa, where buk genes linked to Clostridium perfringens dominated in carnivores and but genes associated with Ruminococcaceae bacterium D16 were specific for herbivores and omnivores. Whereas 16S rRNA gene analysis showed similar overall patterns, it was unable to reveal communities at the same depth and resolution as the functional gene-targeted approach. This study demonstrates that butyrate producers are abundant across vertebrates exhibiting great functional redundancy and that diet is the primary determinant governing the composition of the butyrate-producing guild. PMID:25343515

  14. TESS line: a laboratory line of the musk shrew (Suncus murinus, Insectivora), triple-homozygous for the curly hair (ch), cream coat-color (cr) and red-eyed dilution (rd) genes and segregating the sucrase deficients (suc/suc).

    PubMed

    Ohno, T; Oda, S; Namikawa, T

    1994-01-01

    The TESS line, the first tester line of the Suncus has been developed. The TESS shrews are homozygous for three morphological mutant genes, ch, cr and rd. The gene (suc) for sucrase activity deficiency in intestinal brush-border membranes also exists in the line, and its frequency was 34.3%. The deficients could easily be identified by the drastic body-weight losing up to more than 15% of the initial weight, that aroused two days after replacement of the drinking water for its 10%-sucrose solution. The TESS shrews have been maintained as a closed-colony consisting of more than 30 individuals, and will be utilized in linkage analysis with the four loci (ch, cr, rd and suc). PMID:8119332

  15. Differential temporal changes in brain and gut substance P mRNA expression throughout the time-course of cisplatin-induced vomiting in the least shrew (Cryptotis parva).

    PubMed

    Dey, Dilip; Abad, Joseph; Ray, Andrew P; Darmani, Nissar A

    2010-01-15

    Cisplatin and related chemotherapeutics are potent emetogens in humans and least shrews, a small animal emesis model which also vomits in response to substance P (SP). The SP-producing preprotachykinin-1 (PPT1) mRNA is transcribed from the Tac1 gene, which has been sequenced from several animal species and humans and is highly conserved. Despite its prominent role in chemotherapy-induced vomiting, the tachykininergic system is not well-characterized in emesis-competent species. This study was undertaken to further establish Cryptotis parva as an emesis model, by sequencing and characterizing SP mRNA, and then comparing the least shrew tachykininergic system to other mammalian species (vomiting and non-vomiting). The cDNA for least shrew beta-PPT1 was successfully cloned and partially sequenced, and found to be 90% homologous to the human sequence, with the SP-producing portion identical to humans. Initial in situ hybridization results demonstrated induction of beta-PPT1 mRNA in the gut following cisplatin administration. These were followed up with mRNA quantification (via QPCR) at multiple time points following cisplatin injection. PPT1 mRNA levels in the brain spiked at 4 h (19-fold increase) and 24 h (20-fold increase) in correlation with cisplatin-induced emesis. PPT1 mRNA in the gut spiked at 28 h (approximately 6.5-fold increase), correlated with the later phase of vomiting. These results validate the least shrew as a tachykinin model at the molecular level. PMID:19912998

  16. Cisplatin causes over-expression of tachykinin NK(1) receptors and increases ERK1/2- and PKA- phosphorylation during peak immediate- and delayed-phase emesis in the least shrew (Cryptotis parva) brainstem.

    PubMed

    Darmani, Nissar A; Dey, Dilip; Chebolu, Seetha; Amos, Barry; Kandpal, Raj; Alkam, Tursun

    2013-01-01

    Scant information is available regarding the effects of cisplatin on the expression profile of tachykinin NK(1) receptors and downstream signaling during cisplatin-induced emesis. Cisplatin causes peak early- and delayed-phase emesis in the least shrew at 1-2 and 33 h post-injection. To investigate the expression profile of NK(1) receptor during both emetic phases, we cloned the cDNA corresponding to a ~700 base pairs of mRNA flanked by two stretches of nucleotides conserved among different species and demonstrated that the shrew NK(1) receptor nucleotide sequence shares ~90% sequence identity with the human NK(1) receptor. Of the 12 time-points tested, significant increases in expression levels of NK(1) receptor mRNA in the shrew brainstem occurred at 2 and 28 h post-cisplatin injection, whereas intestinal NK(1) receptor mRNA was increased at 28 h. Shrew brainstem and intestinal substance P mRNA levels also tended to increase during the two phases. Furthermore, expression levels of NK(1) receptor protein were significantly increased in the brainstem at 2, 8, and 33 h post-cisplatin. No change in brainstem 5-HT(3) receptor protein expression was observed. The temporal enhancements in NK(1) receptor protein expression were mirrored by significant increases in the phosphorylation status of the brainstem ERK1/2 at 2, 8, and 33 h post-cisplatin. Phosphorylation of PKA significantly increased at 33rd and 40th hour. Our results indicate associations between cisplatin's peak immediate- and delayed-phase vomiting frequency with increased: (1) expression levels of NK(1) receptor mRNA and its protein level, and (2) downstream NK(1) receptor-mediated phosphorylation of ERK1/2 and PKA signaling. PMID:23001014

  17. These studies were conducted to assess the effects of lead toxicity on exploratory behavior and running. Effects of lead on exploratory behavior and running speed in the shrew, Blarina brevicauda (Insectivora).

    PubMed

    Punzo, F; Farmer, C

    2003-10-01

    These studies were conducted to assess the effects of lead toxicity on exploratory behavior and running speed in the short-tailed shrew, Blarina brevicauda. Shrews from the experimental group received 25 mg/kg/day of lead acetate in their drinking water for a period of 90 days. Control subjects received sodium acetate. Exploratory behavior was determined using a computerized activity chamber where movements of test subjects broke infrared beams projected onto the floor of the apparatus. Time spent (sec) in exploration was recorded over eight 6-min intervals. Running speed (km/hr) was measured in a microprocessor-controlled rectangular racetrack fitted with photocell timers. With respect to time spent in exploration, there were significant differences between lead-exposed (20.5-23.9 sec per 6-min testing session) and control subjects (6.8-8.1 sec) after the sixth testing interval in the activity chamber. With respect to maximal running speed, control subjects ran significantly faster (mean: 14.8 km/hr) than their lead-exposed counterparts (5.83 km/hr). Lead-exposed animals exhibited hyperactivity and increased random locomotor movements. They would frequently bump into the walls and their movements were more random. Controls typically ran along the racetrack in a straight line. These results represent the first data for the effects of lead exposure on exploratory behavior and running speed for shrews. PMID:15248655

  18. A new amphicyonid (Mammalia, Carnivora, Amphicyonidae) from the late middle Miocene of northern Thailand and a review of the amphicyonine record in Asia

    NASA Astrophysics Data System (ADS)

    Peign, Stphane; Chaimanee, Yaowalak; Yamee, Chotima; Tian, Pannipa; Jaeger, Jean-Jacques

    2006-04-01

    Recent field research conducted in the middle Miocene basin of Mae Moh, northern Thailand, allow discovering dental remains of a new amphicyonid (Mammalia, Carnivora, Amphicyonidae). A thorough comparison with all known Asian and non-Asian Miocene genera of Amphicyonidae supports the assignment of these specimens to a new amphicyonine, Maemohcyon potisati gen. et sp. nov. We propose the first review of the fossil record of the Amphicyoninae and we discuss the possible geographic origin and phylogenetic relationships of this new taxon. It appears that Maemohcyon does not have close relationships with contemporary ( Amphicyon, Pseudocyon, Ischyrocyon, Pliocyon) or earlier ( Ictiocyon, Pseudarctos, Cynelos, Ysengrinia) genera. We suggest that the Maemohcyon lineage probably arrived much earlier than 13 Ma (age of Mae Moh fauna) and evolved in this insulated region until the late middle Miocene.

  19. Brain Volume of the Newly-Discovered Species Rhynchocyon udzungwensis (Mammalia: Afrotheria: Macroscelidea): Implications for Encephalization in Sengis

    PubMed Central

    Kaufman, Jason A.; Turner, Gregory H.; Holroyd, Patricia A.; Rovero, Francesco; Grossman, Ari

    2013-01-01

    The Gray-faced Sengi (Rhynchocyon udzungwensis) is a newly-discovered species of sengi (elephant-shrew) and is the largest known extant representative of the order Macroscelidea. The discovery of R. udzungwensis provides an opportunity to investigate the scaling relationship between brain size and body size within Macroscelidea, and to compare this allometry among insectivorous species of Afrotheria and other eutherian insectivores. We performed a spin-echo magnetic resonance imaging (MRI) scan on a preserved adult specimen of R. udzungwensis using a 7-Tesla high-field MR imaging system. The brain was manually segmented and its volume was compiled into a dataset containing previously-published allometric data on 56 other species of insectivore-grade mammals including representatives of Afrotheria, Soricomorpha and Erinaceomorpha. Results of log-linear regression indicate that R. udzungwensis exhibits a brain size that is consistent with the allometric trend described by other members of its order. Inter-specific comparisons indicate that macroscelideans as a group have relatively large brains when compared with similarly-sized terrestrial mammals that also share a similar diet. This high degree of encephalization within sengis remains robust whether sengis are compared with closely-related insectivorous afrotheres, or with more-distantly-related insectivorous laurasiatheres. PMID:23516530

  20. Patterns of mRNA and protein expression during minus-lens compensation and recovery in tree shrew sclera

    PubMed Central

    Gao, Hong; Frost, Michael R.; Norton, Thomas T.

    2011-01-01

    Purpose To increase our understanding of the mechanisms that remodel the sclera during the development of lens-induced myopia, when the sclera responds to putative “go” signals of retinal origin, and during recovery from lens-induced myopia, when the sclera responds to retinally-derived “stop” signals. Methods Seven groups of tree shrews were used to examine mRNA levels during minus lens compensation and recovery. Starting 24 days after eye opening (days of visual experience [VE]) lens compensation animals wore a monocular –5D lens for 1, 4, or 11 days. Recovery animals wore the –5D lens for 11 days, which was then removed for 1 or 4 days. Normal animals were examined at 24 and 38 days of VE. All groups contained 8 animals. Scleral mRNA levels were examined in the treated and contralateral control eyes with quantitative real-time polymerase chain reaction (qPCR) for 27 genes divided into four categories: 1) signaling molecules, 2) matricellular proteins, 3) metalloproteinases (MPs) and tissue inhibitors of metalloproteinases (TIMPs), and 4) cell adhesion and other proteins. Four groups (n=5 per group) were used to examine protein levels. One group wore a –5D lens for 4 days. A second group recovered for 4 days after 11 days of −5D lens treatment. Two groups were used to examine age-matched normal protein levels at 28 and 39 days of VE. The levels of six scleral proteins that showed differential mRNA expression were examined with quantitative western blots. Results Nineteen of the genes showed differential (treated eye versus control eye) expression of mRNA levels in at least one group of animals. Which genes showed differential expression differed after 1 and 4 days of compensation and after 1 or 4 days of recovery. The mRNA level for one gene, a disintegrin and metalloproteinase with thrombospondin motifs 1 (ADAMTS1), was upregulated in the treated eyes after 1 day of compensation. After 4 days, transforming growth factor beta receptor 3 (TGFBR3), transforming growth factor-beta-induced protein ig-h3 (TGFBI), and matrix metalloproteinase 14 (MMP14) mRNA levels were upregulated. Downregulated were mRNA levels for transforming growth factor beta-1 (TGFB1), transforming growth factor beta-2 (TGFB2), thrombospondin 1 (THBS1), tenascin (TNC), osteonectin (SPARC), osteopontin (SPP1), tissue inhibitor of metalloproteinases 3 (TIMP3), and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5). After 11 days of lens wear, there was no differential expression. During recovery, after 1 day, treated-eye mRNA downregulation was found for TGFB2, TGFBR1, TGFBR2, TGFBR3, SPARC, ADAMTS1, ADAMTS5, syndecan 4 (SDC4), and collagen type VI, alpha 1 (COL6A1). After 4 days, TGFB1, TGFB2, TGFB3, THBS2, and TIMP3 mRNA levels were upregulated in the recovering eye. Significant downregulation, relative to normal eyes, was found in both the control and treated eyes for most genes after 1 day of compensation; a similar decrease was found, compared to lens-compensated eyes, after one day of recovery. Protein levels for THBS1 showed positive correlation with the differential mRNA levels and TGFBR3 showed a negative correlation. No differential protein expression was found for TGFB2, TGFBI, MMP14, and TIMP3. Conclusions The different patterns of differential mRNA expression during minus lens compensation (hyperopia) and recovery (myopia) show that scleral fibroblasts distinguish between “go” and “stop” conditions. There is evidence of binocular global downregulation of genes at the start of both lens wear and recovery. As additional information accumulates about changes in gene expression that occur during compensation and recovery the “signature” of differential changes may help us to understand in more detail how the sclera responds in “go” and “stop” conditions. PMID:21541268

  1. Unusual ampullary sperm crypts, and behavior and role of the cumulus oophorus, in the oviduct of the least shrew, Cryptotis parva.

    PubMed

    Bedford, J M; Mock, O B; Phillips, D M

    1997-05-01

    The gametes of the least shrew, Cryptotis parva, were studied in regard to their maturation and structure, and with particular emphasis on their behavior in the fallopian tube, from the time of ovulation until the appearance of two-cell embryos beginning some 9 h after ovulation. Cryptotis spermatozoa are organized according to the conventional eutherian mold, with the exception of a barbed perforatorium and an unusual plasma membrane density lent by a bristly coat where it overlies the acrosome rim. In the epididymis they undergo a maturation of the capacity for motility and an -S-S-related stabilization of the nucleus and tail organelles, with the cauda housing only approximately 4-5 million spermatozoa. Mating involves penile locking and also the deposition of a modest vaginal plug that covers the cervix. The short (4-5 mm) fallopian tube has three regions-a simple isthmus, a relatively narrow ampulla populated throughout by ciliated crypts, and a crypt-free terminal infundibulum-the fertilization site. Unlike the situation in most mammals, the tubal isthmus was devoid of spermatozoa in mated females before and after ovulation, which occurred approximately 13 h post-hCG and produced a mean of 5.7 ova. However, the ampulla then housed approximately 1500 active cells in groups within the ciliated crypts, sometimes together with leukocytes but with few spermatozoa above in the infundibulum. Within about 1 h after their ovulation from approximately 400-microm follicles, eggs were penetrated while in the infundibulum despite the nonexpanded hyaluronidase-resistant state of the cumulus oophorus. However, on moving down to the ampulla by 2-4 h after ovulation, the dense cumulus around fertilized eggs appeared to proliferate and began to disperse coincidentally with secretion of a hyaluronidase-sensitive matrix in which hundreds of motile spermatozoa often became enmeshed. This cumulus change also occurred around unfertilized eggs, though more slowly, but not around fertilized or unfertilized eggs cultured in vitro. Thus, cumulus matrix production appeared to be stimulated to an important degree by factors in the oviduct, not by preovulatory gonadotropins as in many mammals. Although cumulus-invested eggs were fertilized readily in vitro, cumulus-free eggs of the same age were never fertilized, and spermatozoa bound to the zona pellucida had intact acrosomes. This and related evidence from other shrews makes it seem likely that the soricid cumulus has an essential role in fertilization and may induce the acrosome reaction. PMID:9160726

  2. The head-twitch response in the least shrew (Cryptotis parva) is a 5-HT2- and not a 5-HT1C-mediated phenomenon.

    PubMed

    Darmani, N A; Mock, O B; Towns, L C; Gerdes, C F

    1994-06-01

    Our initial studies suggested that the 5-HT2/1C agonist (+/-)-1-(2,5-dimethoxy-4-iodophenyl-2-aminopropane [(+/-)-DOI] produces both the head-twitch response (HTR) and the ear-scratch response (ESR) in mice via stimulation of 5-HT2 receptors. However, challenge studies revealed that these behaviors are produced via two different receptors (possibly 5-HT2 and 5-HT1C). Due to a lack of selective agents one cannot designate a particular response for the activation of a specific receptor. The purpose of the present study was to investigate such behaviors in the least shrew, which is more sensitive to (+/-)-DOI than rodents. IP injection of (+/-)-DOI in shrews produced a dose-dependent (bell-shaped) and time-dependent increase in the HTR frequency. The (+/-)-DOI-induced HTR was equipotently and completely attenuated by the 5-HT2/1C antagonists ketanserin and spiperone. The 5-HT1C antagonist with 5-HT2 agonist action, lisuride, also produced the HTR in a bell-shaped dose- and time-dependent fashion. Central injections of both (+/-)-DOI (0.2 microgram) and lisuride (0.5 microgram) also induced the behavior. Both peripheral and central administration of lisuride failed to produce the ESR. (+/-)-DOI significantly induced the ESR only at the highest dose tested (2.5 mg/kg, IP). Centrally administered (+/-)-DOI (0.2 microgram) produced more ESRs relative to vehicle controls; however, the difference did not attain significance. At low doses (0.31 and 0.63 mg/kg), (+/-)-DOI had no effect on locomotor activity, but it significantly attenuated the behavior at larger doses. Both low and high doses of lisuride increased the motor activity. Spiperone dose-dependently suppressed locomotion, whereas ketanserin had no effect. The present results suggest that the HTR is a 5-HT2 receptor-mediated event and changes in locomotor activity do not affect the induced HTR. PMID:8090805

  3. Spatiotemporal Profile of Voltage-Sensitive Dye Responses in the Visual Cortex of Tree Shrews Evoked by Electric Microstimulation of the Dorsal Lateral Geniculate and Pulvinar Nuclei

    PubMed Central

    Thomas, Sbastien; Petry, Heywood M.; Bickford, Martha E.; Casanova, Christian

    2015-01-01

    The primary visual cortex (V1) receives its main thalamic drive from the dorsal lateral geniculate nucleus (dLGN) through synaptic contacts terminating primarily in cortical layer IV. In contrast, the projections from the pulvinar nucleus to the cortex are less clearly defined. The pulvinar projects predominantly to layer I in V1, and layer IV in extrastriate areas. These projection patterns suggest that the pulvinar nucleus most strongly influences (drives) activity in cortical areas beyond V1. Should this hypothesis be true, one would expect the spatiotemporal responses evoked by pulvinar activation to be different in V1 and extrastriate areas, reflecting the different connectivity patterns. We investigated this issue by analyzing the spatiotemporal dynamics of cortical visual areas' activity following thalamic electrical microstimulation in tree shrews, using optical imaging and voltage-sensitive dyes. As expected, electrical stimulation of the dLGN induced fast and local responses in V1, as well as in extrastriate and contralateral cortical areas. In contrast, electrical stimulation of the pulvinar induced fast and local responses in extrastriate areas, followed by weak and diffuse activation in V1 and contralateral cortical areas. This study highlights spatiotemporal cortical activation characteristics induced by stimulation of first (dLGN) and high-order (pulvinar) thalamic nuclei. SIGNIFICANCE STATEMENT The pulvinar nucleus represents the main extrageniculate thalamic visual structure in higher-order mammals, but its exact role remains enigmatic. The pulvinar receive prominent inputs from virtually all visual cortical areas. Cortico-thalamo-cortical pathways through the pulvinar nuclei may then provide a complementary route for corticocortical information flow. One step toward the understanding of the role of transthalamic corticocortical pathways is to determine the nature of the signals transmitted between the cortex and the thalamus. By performing, for the first time, high spatiotemporal mesoscopic imaging on tree shrews (the primate's closest relative) through the combination of voltage-sensitive dye recordings and brain stimulation, we revealed clear evidence of distinct thalamocortical functional connectivity pattern originating from the geniculate nucleus and the pulvinar nuclei. PMID:26311771

  4. The testis of greater white-toothed shrew Crocidura russula in Southern European populations: a case of adaptive lack of seasonal involution?

    PubMed

    Massoud, Diaa; Barrionuevo, Francisco J; Ortega, Esperanza; Burgos, Miguel; Jimnez, Rafael

    2014-07-01

    Males of all seasonal breeding mammals undergo circannual periods of testis involution resulting in almost complete ablation of the germinative epithelium. We performed a morphometric, histological, hormonal, and gene-expression study of the testes from winter and summer males of the greater white-toothed shrew, Crocidura russula, in populations of the southeastern Iberian Peninsula. Unexpectedly, we found no significant differences between the two study groups. Surprisingly, female data confirmed a non-breeding period in the summer, evidencing that males retain full testis function even when most females are not receptive. This situation, which has not been described before, does not occur in northern populations of the same species where, in addition, the reproductive cycle is inverted with respect to those in the south, as the non-breeding period occurs in winter instead in summer. Considering that the non-reproductive period shortens at lower latitude locations, we hypothesize that in southern populations the non-breeding period is short enough to make testis regression inefficient in terms of energy savings, because: (1) testes of C. russula are very small, a condition derived from their monogamy that implies low investment in spermatogenesis; and (2) the spermatogenic cycle of this species is slow and long. The inverted seasonal breeding cycle and the lack of seasonal testis regression described here are new adaptive processes that deserve further research, and provide evidence that the genetic and hormonal mechanisms controlling reproduction timing in mammals are more plastic and versatile than initially suspected. PMID:24895181

  5. Orthoptera as intermediate hosts of Staphylocystis furcata (Stieda, 1862) (Cestoda: Hymenolepididae).

    PubMed

    Rysav, B

    1989-01-01

    Cysticercoids of Staphylocystis furcata (Stieda, 1962), the adults of which parasitize the shrews (Soricidae), were found in the thoracic and abdominal cavities of orthopterous insects (Orthoptera, Acridioidea) belonging to five species: Chorthippus apricarius (L.), Chorthippus paralellus (Zett.), Omocestus viridulus (L.), Chrysochraon brachypterus (Ocsk.), and Chrysochraon dispar (Germ.). The cysticercoids are described and their incidence in both sexes of the examined intermediate hosts is compared. PMID:2767549

  6. Additive antiemetic efficacy of low-doses of the cannabinoid CB(1/2) receptor agonist ?(9)-THC with ultralow-doses of the vanilloid TRPV1 receptor agonist resiniferatoxin in the least shrew (Cryptotis parva).

    PubMed

    Darmani, Nissar A; Chebolu, Seetha; Zhong, Weixia; Trinh, Chung; McClanahan, Bryan; Brar, Rajivinder S

    2014-01-01

    Previous studies have shown that cannabinoid CB1/2 and vanilloid TRPV1 agonists (delta-9-tetrahydrocannabinol (?(9)-THC) and resiniferatoxin (RTX), respectively) can attenuate the emetic effects of chemotherapeutic agents such as cisplatin. In this study we used the least shrew to demonstrate whether combinations of varying doses of ?(9)-THC with resiniferatoxin can produce additive antiemetic efficacy against cisplatin-induced vomiting. RTX by itself caused vomiting in a bell-shaped dose-dependent manner with maximal vomiting at 18 ?g/kg when administered subcutaneously (s.c.) but not intraperitoneally (i.p.). ?(9)-THC up to 10 mg/kg provides only 80% protection of least shrews from cisplatin-induced emesis with an ID50 of 0.3-1.8 mg/kg. Combinations of 1 or 5 ?g/kg RTX with varying doses of ?(9)-THC completely suppressed both the frequency and the percentage of shrews vomiting with ID50 dose values 5-50 times lower than ?(9)-THC doses tested alone against cisplatin. A less potent TRPV1 agonist, capsaicin, by itself did not cause emesis (i.p. or s.c.), but it did significantly reduce vomiting induced by cisplatin given after 30 min but not at 2 h. The TRPV1-receptor antagonist, ruthenium red, attenuated cisplatin-induced emesis at 5mg/kg; however, another TRPV1-receptor antagonist, capsazepine, did not. In summary, we present evidence that combination of CB1/2 and TRPV1 agonists have the capacity to completely abolish cisplatin-induced emesis at doses that are ineffective when used individually. PMID:24157976

  7. L-type calcium channels contribute to 5-HT3-receptor-evoked CaMKII? and ERK activation and induction of emesis in the least shrew (Cryptotis parva).

    PubMed

    Hutchinson, Tarun E; Zhong, Weixia; Chebolu, Seetha; Wilson, Sean M; Darmani, Nissar A

    2015-05-15

    Activation of serotonergic 5-HT3 receptors by its selective agonist 2-methyl serotonin (2-Me-5-HT) induces vomiting, which is sensitive to selective antagonists of both 5-HT3 receptors (palonosetron) and L-type calcium channels (LTCC) (amlodipine or nifedipine). Previously we demonstrated that 5-HT3 receptor activation also causes increases in a palonosetron-sensitive manner in: i) intracellular Ca(2+) concentration, ii) attachment of calmodulin (CaM) to 5-HT3 receptor, and iii) phosphorylation of Ca(2+)/calmodulin-dependent protein kinase II? (CaMKII?) and extracellular-signal-regulated kinase 1/2 (ERK1/2). Here, we investigate the role of the short-acting LTCC blocker nifedipine on 2-Me-5-HT-evoked intracellular Ca(2+) increase and on downstream intracellular emetic signaling, which have been shown to be coupled with 2-Me-5-HT?s emetic effects in the least shrew. Using the cell-permeant Ca(2+) indicator fluo-4 AM, here we present evidence for the contribution of Ca(2+) influx through LTCCs (sensitive to nifedipine) in 2-Me-5-HT (1M) -evoked rise in cytosolic Ca(2+) levels in least shrew brainstem slices. Nifedipine pretreatment (10mg/kg, s.c.) also suppressed 2-Me-5-HT-evoked interaction of 5-HT3 receptors with CaM as well as phosphorylation of CaMKII? and ERK1/2 in the least shrew brainstem, and 5-HT3 receptors -CaM colocalization in jejunum of the small intestine. In vitro exposure of isolated enterochromaffin cells of the small intestine to 2-Me-5-HT (1M) caused CaMKII? phosphorylation, which was also abrogated by nifedipine pretreatment (0.1M). In addition, pretreatment with the CaMKII inhibitor KN62 (10mg/kg, i.p.) suppressed emesis and also the activation of CaMKII?, and ERK in brainstem caused by 2-Me-5-HT (5mg/kg, i.p.). This study provides further mechanistic explanation for our published findings that nifedipine can dose-dependently protect shrews from 2-Me-5-HT-induced vomiting. PMID:25748600

  8. Cross-species chromosome painting unveils cytogenetic signatures for the Eulipotyphla and evidence for the polyphyly of Insectivora.

    PubMed

    Ye, Jianping; Biltueva, Larisa; Huang, Ling; Nie, Wenhui; Wang, Jinhuan; Jing, Meidong; Su, Weiting; Vorobieva, Nadezhda V; Jiang, Xuelong; Graphodatsky, Alexander S; Yang, Fengtang

    2006-01-01

    Insectivore-like animals are traditionally believed among the first eutherian mammals that have appeared on the earth. The modern insectivores are thus crucial for understanding the systematics and phylogeny of eutherian mammals as a whole. Here cross-species chromosome painting, with probes derived from flow-sorted chromosomes of human, was used to delimit the homologous chromosomal segments in two Soricidae species, the common shrew (Sorex araneus, 2n = 20/21), and Asiatic short-tailed shrew (Blarinella griselda, 2n = 44), and one Erinaceidae species, the shrew-hedgehog (Neotetracus sinensis, 2n = 32), and human. We report herewith the first comparative maps for the Asiatic short-tailed shrew and the shrew-hedgehog, in addition to a refined comparative map for the common shrew. In total, the 22 human autosomal paints detected 40, 51 and 58 evolutionarily conserved segments in the genomes of common shrew, Asiatic short-tailed shrew, and shrew-hedgehog, respectively, demonstrating that the common shrew has retained a conserved genome organization while the Asiatic short-tailed shrew and shrew-hedgehog have relatively rearranged genomes. In addition to confirming the existence of such ancestral human segmental combinations as HSA 3/21, 12/22, 14/15 and 7/16 that are shared by most eutherian mammals, our study reveals a shared human segmental combination, HSA 4/20, that could phylogenetically unite the Eulipotyphlan (i.e., the core insectivores) species. Our results provide cytogenetic evidence for the polyphyly of the order Insectivora and additional data for the eventual reconstruction of the ancestral eutherian karyotype. PMID:16544189

  9. High levels of antimicrobial resistance among escherichia coli isolates from livestock farms and synanthropic rats and shrews in the Mekong Delta of Vietnam.

    PubMed

    Nhung, N T; Cuong, N V; Campbell, J; Hoa, N T; Bryant, J E; Truc, V N T; Kiet, B T; Jombart, T; Trung, N V; Hien, V B; Thwaites, G; Baker, S; Carrique-Mas, J

    2015-02-01

    In Mekong Delta farms (Vietnam), antimicrobials are extensively used, but limited data are available on levels of antimicrobial resistance (AMR) among Escherichia coli isolates. We performed a structured survey of AMR in E. coli isolates (n = 434) from 90 pig, chicken, and duck farms. The results were compared with AMR among E. coli isolates (n = 234) from 66 small wild animals (rats and shrews) trapped on farms and in forests and rice fields. The isolates were susceptibility tested against eight antimicrobials. E. coli isolates from farmed animals were resistant to a median of 4 (interquartile range [IQR], 3 to 6) antimicrobials versus 1 (IQR, 1 to 2) among wild mammal isolates (P < 0.001). The prevalences of AMR among farmed species isolates (versus wild animals) were as follows: tetracycline, 84.7% (versus 25.6%); ampicillin, 78.9% (versus 85.9%); trimethoprim-sulfamethoxazole, 52.1% (versus 18.8%); chloramphenicol, 39.9% (versus 22.5%); amoxicillin-clavulanic acid, 36.6% (versus 34.5%); and ciprofloxacin, 24.9% (versus 7.3%). The prevalence of multidrug resistance (MDR) (resistance against three or more antimicrobial classes) among pig isolates was 86.7% compared to 66.9 to 72.7% among poultry isolates. After adjusting for host species, MDR was ?8 times greater among isolates from wild mammals trapped on farms than among those trapped in forests/rice fields (P < 0.001). Isolates were assigned to unique profiles representing their combinations of susceptibility results. Multivariable analysis of variance indicated that AMR profiles from wild mammals trapped on farms and those from domestic animals were more alike (R(2) range, 0.14 to 0.30) than E. coli isolates from domestic animals and mammals trapped in the wild (R(2) range, 0.25 to 0.45). The results strongly suggest that AMR on farms is a key driver of environmental AMR in the Mekong Delta. PMID:25398864

  10. Biomic Specialization and Speciation Rates in Ruminants (Cetartiodactyla, Mammalia): A Test of the Resource-Use Hypothesis at the Global Scale

    PubMed Central

    Cantalapiedra, Juan L.; Hernndez Fernndez, Manuel; Morales, Jorge

    2011-01-01

    The resource-use hypothesis proposed by E.S. Vrba predicts that specialist species have higher speciation and extinction rates than generalists because they are more susceptible to environmental changes and vicariance. In this work, we test some of the predictions derived from this hypothesis on the 197 extant and recently extinct species of Ruminantia (Cetartiodactyla, Mammalia) using the biomic specialization index (BSI) of each species, which is based on its distribution within different biomes. We ran 10000 Monte Carlo simulations of our data in order to get a null distribution of BSI values against which to contrast the observed data. Additionally, we drew on a supertree of the ruminants and a phylogenetic likelihood-based method (QuaSSE) for testing whether the degree of biomic specialization affects speciation rates in ruminant lineages. Our results are consistent with the predictions of the resource-use hypothesis, which foretells a higher speciation rate of lineages restricted to a single biome (BSI?=?1) and higher frequency of specialist species in biomes that underwent high degree of contraction and fragmentation during climatic cycles. Bovids and deer present differential specialization across biomes; cervids show higher specialization in biomes with a marked hydric seasonality (tropical deciduous woodlands and schlerophyllous woodlands), while bovids present higher specialization in a greater variety of biomes. This might be the result of divergent physiological constraints as well as a different biogeographic and evolutionary history. PMID:22174888

  11. High Levels of Antimicrobial Resistance among Escherichia coli Isolates from Livestock Farms and Synanthropic Rats and Shrews in the Mekong Delta of Vietnam

    PubMed Central

    Nhung, N. T.; Cuong, N. V.; Campbell, J.; Hoa, N. T.; Bryant, J. E.; Truc, V. N. T.; Kiet, B. T.; Jombart, T.; Trung, N. V.; Hien, V. B.; Thwaites, G.; Baker, S.

    2014-01-01

    In Mekong Delta farms (Vietnam), antimicrobials are extensively used, but limited data are available on levels of antimicrobial resistance (AMR) among Escherichia coli isolates. We performed a structured survey of AMR in E. coli isolates (n = 434) from 90 pig, chicken, and duck farms. The results were compared with AMR among E. coli isolates (n = 234) from 66 small wild animals (rats and shrews) trapped on farms and in forests and rice fields. The isolates were susceptibility tested against eight antimicrobials. E. coli isolates from farmed animals were resistant to a median of 4 (interquartile range [IQR], 3 to 6) antimicrobials versus 1 (IQR, 1 to 2) among wild mammal isolates (P < 0.001). The prevalences of AMR among farmed species isolates (versus wild animals) were as follows: tetracycline, 84.7% (versus 25.6%); ampicillin, 78.9% (versus 85.9%); trimethoprim-sulfamethoxazole, 52.1% (versus 18.8%); chloramphenicol, 39.9% (versus 22.5%); amoxicillin-clavulanic acid, 36.6% (versus 34.5%); and ciprofloxacin, 24.9% (versus 7.3%). The prevalence of multidrug resistance (MDR) (resistance against three or more antimicrobial classes) among pig isolates was 86.7% compared to 66.9 to 72.7% among poultry isolates. After adjusting for host species, MDR was ∼8 times greater among isolates from wild mammals trapped on farms than among those trapped in forests/rice fields (P < 0.001). Isolates were assigned to unique profiles representing their combinations of susceptibility results. Multivariable analysis of variance indicated that AMR profiles from wild mammals trapped on farms and those from domestic animals were more alike (R2 range, 0.14 to 0.30) than E. coli isolates from domestic animals and mammals trapped in the wild (R2 range, 0.25 to 0.45). The results strongly suggest that AMR on farms is a key driver of environmental AMR in the Mekong Delta. PMID:25398864

  12. Thapsigargin-induced activation of Ca(2+)-CaMKII-ERK in brainstem contributes to substance P release and induction of emesis in the least shrew.

    PubMed

    Zhong, Weixia; Chebolu, Seetha; Darmani, Nissar A

    2016-04-01

    Cytoplasmic calcium (Ca(2+)) mobilization has been proposed to be an important factor in the induction of emesis. The selective sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA) inhibitor thapsigargin, is known to deplete intracellular Ca(2+) stores, which consequently evokes extracellular Ca(2+) entry through cell membrane-associated channels, accompanied by a prominent rise in cytosolic Ca(2+). A pro-drug form of thapsigargin is currently under clinical trial as a targeted cancer chemotherapeutic. We envisioned that the intracellular effects of thapsigargin could cause emesis and planned to investigate its mechanisms of emetic action. Indeed, thapsigargin did induce vomiting in the least shrew in a dose-dependent and bell-shaped manner, with maximal efficacy (100%) at 0.5 mg/kg (i.p.). Thapsigargin (0.5 mg/kg) also caused increases in c-Fos immunoreactivity in the brainstem emetic nuclei including the area postrema (AP), nucleus tractus solitarius (NTS) and dorsal motor nucleus of the vagus (DMNX), as well as enhancement of substance P (SP) immunoreactivity in DMNX. In addition, thapsigargin (0.5 mg/kg, i.p.) led to vomit-associated and time-dependent increases in phosphorylation of Ca(2+)/calmodulin kinase IIα (CaMKIIα) and extracellular signal-regulated protein kinase 1/2 (ERK1/2) in the brainstem. We then explored the suppressive potential of diverse chemicals against thapsigargin-evoked emesis including antagonists of: i) neurokinin-1 receptors (netupitant), ii) the type 3 serotonin receptors (palonosetron), iii) store-operated Ca(2+) entry (YM-58483), iv) L-type Ca(2+) channels (nifedipine), and v) SER Ca(2+)-release channels inositol trisphosphate (IP3Rs) (2-APB)-, and ryanodine (RyRs) (dantrolene)-receptors. In addition, the antiemetic potential of inhibitors of CaMKII (KN93) and ERK1/2 (PD98059) were investigated. All tested antagonists/blockers attenuated emetic parameters to varying degrees except palonosetron, however a combination of non-effective doses of netupitant and palonosetron exhibited additive antiemetic efficacy. A low-dose combination of nifedipine and 2-APB plus dantrolene mixture completely abolished thapsigargin-evoked vomiting, CaMKII-ERK1/2 activation and SP elevation. In addition, pretreatment with KN93 or PD98059 suppressed thapsigargin-induced increases in SP and ERK1/2 activation. Intracerebroventricular injection of netupitant suppressed vomiting caused by thapsigargin which suggests that the principal site of evoked emesis is the brainstem. In sum, this is the first study to demonstrate that thapsigargin causes vomiting via the activation of the Ca(2+)-CaMKII-ERK1/2 cascade, which is associated with an increase in the brainstem tissue content of SP, and the evoked emesis occurs through SP-induced activation of neurokinin-1 receptors. PMID:26631534

  13. Phylogenetic systematics and tempo of evolution of the Viverrinae (Mammalia, Carnivora, Viverridae) within feliformians: implications for faunal exchanges between Asia and Africa.

    PubMed

    Gaubert, Philippe; Cordeiro-Estrela, Pedro

    2006-11-01

    We reconstructed the phylogeny of the subfamily Viverrinae (Mammalia, Carnivora, Viverridae) using a approximately 3kb data set in order to reassess timing and patterns of faunal exchanges between Asia and Africa. Maximum parsimony, maximum likelihood, and Bayesian analyses of separated and combined matrices (cytochrome b, transthyretin intron I and IRBP exon 1 [IRBP1]) recovered all the well-supported relationships within feliformian lineages. In addition, IRBP1 supported paraphyly of genus Herpestes and contributed to the resolution of equivocal hypotheses within Viverridae, including (1) the monophyly of Viverrinae, and (2) Viverricula sister-group of the other terrestrial civets (Civettictis and Viverra). The combined analysis yielded a robust phylogeny, recovering monophyly of Prionodontidae and yielding high posterior probabilities for nodes (1) (Prionodontidae, Felidae) and (2) ((Felidae, Prionodontidae), ((Hyaenidae, (Herpestidae, Eupleridae)), Viverridae)). Using a fossil cross-validation method, we estimated the emergence of Viverridae at 34.29Myr, with a separation between the three traditional subfamilies Hemigalinae, Paradoxurinae, and Viverrinae during the Late Oligocene-Early Miocene. The terrestrial civets and the splits between (1) Civettictis and Viverra and (2) Poiana and Genetta were estimated to appear during the Middle Miocene. Parsimony- and maximum likelihood-based methods yielded unambiguous ancestral area reconstructions, including the Asian origin of the family Viverridae, the subfamily Viverrinae, the terrestrial civets and the clade (Civettictis, Viverra). On the grounds of genetic distances, morphological divergence, and divergence time estimates, we propose the erection of the subfamily Genettinae (including Genetta and Poiana). Our analyses suggested two independent migration events from Asia to Africa, during the Middle Miocene (Civettictis) and between the Late Oligocene and Middle Miocene (Genettinae). These results are in agreement with the hypothesis of Miocene routes from Asia to Africa-via the Arabian microplate-that would have involved several independent events of migrations. Couched in the context of the viverrid fossil record, our study calls for a revision of the paleontological data in order to fully appreciate the complexity of Afro-Asian faunal exchanges. PMID:16837215

  14. Serotonin 5-HT3 Receptor-Mediated Vomiting Occurs via the Activation of Ca2+/CaMKII-Dependent ERK1/2 Signaling in the Least Shrew (Cryptotis parva)

    PubMed Central

    Zhong, Weixia; Hutchinson, Tarun E.; Chebolu, Seetha; Darmani, Nissar A.

    2014-01-01

    Stimulation of 5-HT3 receptors (5-HT3Rs) by 2-methylserotonin (2-Me-5-HT), a selective 5-HT3 receptor agonist, can induce vomiting. However, downstream signaling pathways for the induced emesis remain unknown. The 5-HT3R channel has high permeability to extracellular calcium (Ca2+) and upon stimulation allows increased Ca2+ influx. We examined the contribution of Ca2+/calmodulin-dependent protein kinase IIα (Ca2+/CaMKIIα), interaction of 5-HT3R with calmodulin, and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling to 2-Me-5-HT-induced emesis in the least shrew. Using fluo-4 AM dye, we found that 2-Me-5-HT augments intracellular Ca2+ levels in brainstem slices and that the selective 5-HT3R antagonist palonosetron, can abolish the induced Ca2+ signaling. Pre-treatment of shrews with either: i) amlodipine, an antagonist of L-type Ca2+ channels present on the cell membrane; ii) dantrolene, an inhibitor of ryanodine receptors (RyRs) Ca2+-release channels located on the endoplasmic reticulum (ER); iii) a combination of their less-effective doses; or iv) inhibitors of CaMKII (KN93) and ERK1/2 (PD98059); dose-dependently suppressed emesis caused by 2-Me-5-HT. Administration of 2-Me-5-HT also significantly: i) enhanced the interaction of 5-HT3R with calmodulin in the brainstem as revealed by immunoprecipitation, as well as their colocalization in the area postrema (brainstem) and small intestine by immunohistochemistry; and ii) activated CaMKIIα in brainstem and in isolated enterochromaffin cells of the small intestine as shown by Western blot and immunocytochemistry. These effects were suppressed by palonosetron. 2-Me-5-HT also activated ERK1/2 in brainstem, which was abrogated by palonosetron, KN93, PD98059, amlodipine, dantrolene, or a combination of amlodipine plus dantrolene. However, blockade of ER inositol-1, 4, 5-triphosphate receptors by 2-APB, had no significant effect on the discussed behavioral and biochemical parameters. This study demonstrates that Ca2+ mobilization via extracellular Ca2+ influx through 5-HT3Rs/L-type Ca2+ channels, and intracellular Ca2+ release via RyRs on ER, initiate Ca2+-dependent sequential activation of CaMKIIα and ERK1/2, which contribute to the 5-HT3R-mediated, 2-Me-5-HT-evoked emesis. PMID:25121483

  15. Serotonin 5-HT3 receptor-mediated vomiting occurs via the activation of Ca2+/CaMKII-dependent ERK1/2 signaling in the least shrew (Cryptotis parva).

    PubMed

    Zhong, Weixia; Hutchinson, Tarun E; Chebolu, Seetha; Darmani, Nissar A

    2014-01-01

    Stimulation of 5-HT3 receptors (5-HT3Rs) by 2-methylserotonin (2-Me-5-HT), a selective 5-HT3 receptor agonist, can induce vomiting. However, downstream signaling pathways for the induced emesis remain unknown. The 5-HT3R channel has high permeability to extracellular calcium (Ca(2+)) and upon stimulation allows increased Ca(2+) influx. We examined the contribution of Ca(2+)/calmodulin-dependent protein kinase II? (Ca(2+)/CaMKII?), interaction of 5-HT3R with calmodulin, and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling to 2-Me-5-HT-induced emesis in the least shrew. Using fluo-4 AM dye, we found that 2-Me-5-HT augments intracellular Ca(2+) levels in brainstem slices and that the selective 5-HT3R antagonist palonosetron, can abolish the induced Ca(2+) signaling. Pre-treatment of shrews with either: i) amlodipine, an antagonist of L-type Ca(2+) channels present on the cell membrane; ii) dantrolene, an inhibitor of ryanodine receptors (RyRs) Ca2+-release channels located on the endoplasmic reticulum (ER); iii) a combination of their less-effective doses; or iv) inhibitors of CaMKII (KN93) and ERK1/2 (PD98059); dose-dependently suppressed emesis caused by 2-Me-5-HT. Administration of 2-Me-5-HT also significantly: i) enhanced the interaction of 5-HT3R with calmodulin in the brainstem as revealed by immunoprecipitation, as well as their colocalization in the area postrema (brainstem) and small intestine by immunohistochemistry; and ii) activated CaMKII? in brainstem and in isolated enterochromaffin cells of the small intestine as shown by Western blot and immunocytochemistry. These effects were suppressed by palonosetron. 2-Me-5-HT also activated ERK1/2 in brainstem, which was abrogated by palonosetron, KN93, PD98059, amlodipine, dantrolene, or a combination of amlodipine plus dantrolene. However, blockade of ER inositol-1, 4, 5-triphosphate receptors by 2-APB, had no significant effect on the discussed behavioral and biochemical parameters. This study demonstrates that Ca(2+) mobilization via extracellular Ca(2+) influx through 5-HT3Rs/L-type Ca(2+) channels, and intracellular Ca(2+) release via RyRs on ER, initiate Ca(2+)-dependent sequential activation of CaMKII? and ERK1/2, which contribute to the 5-HT3R-mediated, 2-Me-5-HT-evoked emesis. PMID:25121483

  16. Changes in Ucp1, D2 (Dio2) and Glut4 (Slc2a4) mRNA expression in response to short-term cold exposure in the house musk shrew (Suncus murinus).

    PubMed

    Suzuki, Daisuke; Murata, Yoshiharu; Oda, Sen-ichi

    2007-07-01

    The house musk shrew (Suncus murinus), or so-called suncus, is a cold-intolerant mammal, but it is unclear why it is susceptible to low temperatures. Cold-intolerance may be the result of lower thermogenic activity in brown adipose tissue (BAT). The early phase of severe cold exposure is a critical period for suncus. Therefore, we exposed suncus to mildly cold temperatures (10-12 degrees C) for 1 to 48 h to increase non-shivering thermogenesis without causing stress and measured changes in the expression of uncoupling protein 1 (Ucp1), type II iodothyronine 5'-deiodinase (Dio2=D2), and glucose transporter 4 (Slc2a4=Glut4) in BAT. These mRNAs play a major role in non-shivering thermogenesis and are mainly regulated by the sympathetic nervous system via direct beta-noradrenergic innervation of BAT. During cold exposure, Ucp1 expression in BAT increased steadily over time, albeit only slightly. Neither D2 nor Glut4 expression in BAT increased immediately; however, they had increased significantly after 24 h and 48 h of cold exposure. These findings suggest that the responsiveness of mRNA regulation is weak and thus may be involved in cold-intolerance in suncus. PMID:17660682

  17. NMR spectroscopy based metabonomic studies on the comparative biochemistry of the kidney and urine of the bank vole (Clethrionomys glareolus), wood mouse (Apodemus sylvaticus), white toothed shrew (Crocidura suaveolens) and the laboratory rat.

    PubMed

    Griffin, J L; Walker, L A; Garrod, S; Holmes, E; Shore, R F; Nicholson, J K

    2000-11-01

    The metabolic profiles of three wild mammals that vary in their trophic strategies, the herbivorous bank vole (Clethrionomys glareolus), the granivorous wood mouse (Apodemus sylvaticus), and the insectivorous white-toothed shrew (Crocidura suaveolens), were compared with that of a widely used strain of laboratory rat (Sprague Dawley). In conjunction with NMR spectroscopic investigations into the urine and blood plasma composition for these mammals, high resolution magic angle spinning (HRMAS) 1H-nuclear magnetic resonance (NMR) spectroscopy was applied to investigate the composition of intact kidney samples. Adaptation to natural diet affects both renal metabolism and urinary profiles, and while these techniques have been used to study the metabolism of the laboratory rat little is known about wild small mammals. The species were readily separated by their urinary profiles using either crude metabolite ratios or statistical pattern recognition. Bank vole urine contained higher concentrations of aromatic amino acids compared with the other small mammals, while the laboratory rats produced relatively more hippurate. HRMAS 1H-NMR demonstrated striking differences in both lipid concentration and composition between the wild mammals and Sprague Dawley rats. Bank voles contained high concentrations of the aromatic amino acids phenylalanine, tyrosine and tryptophan in all tissue and biofluids studied. This study demonstrates the analytical power of combined NMR techniques for the study of inter-species metabolism and further demonstrates that metabolic data acquired on laboratory animals cannot be extended to wild species. PMID:11126766

  18. Lipotyphla limb myology comparison.

    PubMed

    Neveu, Pauline; Gasc, Jean-Pierre

    2002-05-01

    Fore- and hindlimb muscles were dissected in four species of Lipotyphla: the western European hedgehog Erinaceus europaeus (Erinaceidae, Erinaceinae); the moonrat Echinosorex gymnura (Erinaceidae, Hylomyinae or Galericinae); the tailless tenrec Tenrec ecaudatus (Tenrecidae, Tenrecinae); and the common European white-toothed shrew Crocidura russula (Soricidae, Soricinae). This work completely reviews the limb musculature of these walking mammals. Twelve myological characters were evaluated in order to disclose phylogenetic relationships. The cladogram obtained supported previous ones based on cranial and dental characters. This study shows that myological characters are valuable in phylogenetic analyses. PMID:11921044

  19. A histologically derived stereotaxic atlas and substance P immunohistochemistry in the brain of the least shrew (Cryptotis parva) support its role as a model organism for behavioral and pharmacological research.

    PubMed

    Ray, Andrew P; Darmani, Nissar A

    2007-07-01

    Chemotherapy is an effective treatment but difficult to tolerate due to side effects like vomiting. Studies on the etiology of chemotherapy-related emesis have implicated brainstem nuclei and the neurotransmitter substance P, among other substrates. Since rodents do not vomit, other species have been necessary as alternative models of chemotherapy-induced emesis. Of these, the least shrew (Cryptotis parva) has proven valuable due to its small size, hardiness, and close phylogenetic relationship with primates. However, very little neuroanatomical data on C. parva exist. We used histological and immunohistochemical techniques to provide neuroanatomical data to help validate C. parva as a model organism, especially for emesis research. Brains were sectioned and stained for Nissl substance or myelin, or immunofluorescently labeled for substance P. Sections were photographed, traced, and reconstructed with standardized zero points, and these data used to create a stereotaxic atlas. The brain of C. parva was similar to but smaller than other mammalian brains, with the cerebellum and hippocampus demonstrating the biggest differences. Differences appeared to be related to the small size of the brain and the metabolic compromises required of such a small mammal. Substance P-like immunoreactivity (SPL-IR) was semiquantitatively mapped, and correlated very well with SPL-IR observed in other species. Dense SPL-IR areas included the periaqueductal grey, trigeminal nuclei, dorsal raphe, and emesis-related brainstem nuclei including the area postrema and solitary tract nucleus. These data demonstrate that the anatomical differences between C. parva and other mammals will not preclude its use as a model organism. PMID:17540350

  20. A Histologically-Derived Stereotaxic Atlas and Substance P Immunohistochemistry in the Brain of the Least Shrew (Cryptotis Parva) Support Its Role as a Model Organism for Behavioral and Pharmacological Research

    PubMed Central

    Ray, Andrew P.; Darmani, Nissar A.

    2009-01-01

    Chemotherapy is an effective treatment but difficult to tolerate due to side effects like vomiting. Studies on the etiology of chemotherapy-related emesis have implicated brainstem nuclei and the neurotransmitter Substance P, among other substrates. Since rodents do not vomit, other species have been necessary as alternative models of chemotherapy-induced emesis. Of these, the least shrew (Cryptotis parva) has proven valuable due to its small size, hardiness, and close phylogenetic relationship with primates. However, very little neuroanatomical data on C. parva exist. We used histological and immunohistochemical techniques to provide neuroanatomical data to help validate C. parva as a model organism, especially for emesis research. Brains were sectioned and stained for Nissl substance or myelin, or immunofluorescently labeled for Substance P. Sections were photographed, traced, and reconstructed with standardized zero points, and these data used to create a stereotaxic atlas. The brain of C. parva was similar to but smaller than other mammalian brains, with the cerebellum and hippocampus demonstrating the biggest differences. Differences appeared to be related to the small size of the brain and the metabolic compromises required of such a small mammal. Substance P-like immunoreactivity (SPL-IR) was semiquantitatively mapped, and correlated very well with SPL-IR observed in other species. Dense SPL-IR areas included the periaqueductal grey, trigeminal nuclei, dorsal raphe, and emesis-related brainstem nuclei including the area postrema and solitary tract nucleus. These data demonstrate that the anatomical differences between C. parva and other mammals will not preclude its use as a model organism. PMID:17540350

  1. Broad-spectrum antiemetic potential of the L-type calcium channel antagonist nifedipine and evidence for its additive antiemetic interaction with the 5-HT(3) receptor antagonist palonosetron in the least shrew (Cryptotis parva).

    PubMed

    Darmani, Nissar A; Zhong, Weixia; Chebolu, Seetha; Vaezi, Mariam; Alkam, Tursun

    2014-01-01

    Cisplatin-like chemotherapeutics cause vomiting via release of multiple neurotransmitters (dopamine, serotonin (5-HT), or substance P (SP)) from the gastrointestinal enterochromaffin cells and/or the brainstem via a calcium dependent process. Diverse channels in the plasma membrane allow extracellular Ca(2+) entry into cells for the transmitter release process. Agonists of 5-HT3 receptors increase calcium influx through both 5-HT3 receptors and L-type Ca(2+) channels. We envisaged that L-type calcium agonists such as FPL 64176 should cause vomiting and corresponding antagonists such as nifedipine would behave as broad-spectrum antiemetics. Administration of FPL 64176 did cause vomiting in the least shrew in a dose-dependent fashion. Nifedipine and the 5-HT3 receptor antagonist palonosetron, potently suppressed FPL 64176-induced vomiting, while a combination of ineffective doses of these antagonists was more efficacious. Subsequently, we investigated the broad-spectrum antiemetic potential of nifedipine against diverse emetogens including agonists of serotonergic 5-HT3- (e.g. 5-HT or 2-Me-5-HT), SP tachykinin NK1- (GR73632), dopamine D2- (apomorphine or quinpirole), and cholinergic M1- (McN-A-343) receptors, as well as the non-specific emetogen, cisplatin. Nifedipine by itself suppressed vomiting in a potent and dose-dependent manner caused by the above emetogens except cisplatin. Moreover, low doses of nifedipine potentiated the antiemetic efficacy of non-effective or semi-effective doses of palonosetron against vomiting caused by either 2-Me-5-HT or cisplatin. Thus, our findings demonstrate that activation of L-type calcium channels causes vomiting, whereas blockade of these ion channels by nifedipine-like antagonists not only provides broad-spectrum antiemetic activity but can also potentiate the antiemetic efficacy of well-established antiemetics such as palonosetron. L-type calcium channel antagonists should also provide antiemetic activity against drug-induced vomiting as well as other emetogens including bacterial and viral proteins. PMID:24513517

  2. The historical biogeography of Mammalia

    PubMed Central

    Springer, Mark S.; Meredith, Robert W.; Janecka, Jan E.; Murphy, William J.

    2011-01-01

    Palaeobiogeographic reconstructions are underpinned by phylogenies, divergence times and ancestral area reconstructions, which together yield ancestral area chronograms that provide a basis for proposing and testing hypotheses of dispersal and vicariance. Methods for area coding include multi-state coding with a single character, binary coding with multiple characters and string coding. Ancestral reconstruction methods are divided into parsimony versus Bayesian/likelihood approaches. We compared nine methods for reconstructing ancestral areas for placental mammals. Ambiguous reconstructions were a problem for all methods. Important differences resulted from coding areas based on the geographical ranges of extant species versus the geographical provenance of the oldest fossil for each lineage. Africa and South America were reconstructed as the ancestral areas for Afrotheria and Xenarthra, respectively. Most methods reconstructed Eurasia as the ancestral area for Boreoeutheria, Euarchontoglires and Laurasiatheria. The coincidence of molecular dates for the separation of Afrotheria and Xenarthra at approximately 100 Ma with the plate tectonic sundering of Africa and South America hints at the importance of vicariance in the early history of Placentalia. Dispersal has also been important including the origins of Madagascar's endemic mammal fauna. Further studies will benefit from increased taxon sampling and the application of new ancestral area reconstruction methods. PMID:21807730

  3. Photoreceptor types and distributions in the retinae of insectivores.

    PubMed

    Peichl, L; Knzle, H; Vogel, P

    2000-01-01

    The retinae of insectivores have been rarely studied, and their photoreceptor arrangements and expression patterns of visual pigments are largely unknown. We have determined the presence and distribution of cones in three species of shrews (common shrew Sorex araneus, greater white-toothed shrew Crocidura russula, dark forest shrew Crocidura poensis; Soricidae) and in the lesser hedgehog tenrec Echinops telfairi (Tenrecidae). Special cone types were identified and quantified in flattened whole retinae by antisera/antibodies recognizing the middle-to-long-wavelength-sensitive (M/L-)cone opsin and the short-wavelength-sensitive (S-)cone opsin, respectively. A combination of immunocytochemistry with conventional histology was used to assess rod densities and cone/rod ratios. In all four species the rods dominate at densities of about 230,000-260,000/mm2. M/L- and S-cones are present, comprising between 2% of the photoreceptors in the nocturnal Echinops telfairi and 13% in Sorex araneus that has equal diurnal and nocturnal activity phases. This suggests dichromatic color vision like in many other mammals. A striking feature in all four species are dramatically higher S-cone proportions in ventral than in dorsal retina (0.5% vs. 2.5-12% in Sorex, 5-15% vs. 30-45% in Crocidura poensis, 3-12% vs. 20-50% in Crocidura russula, 10-30% vs. 40-70% in Echinops). The functional and comparative aspects of these structural findings are discussed. PMID:11193110

  4. Automating analog design: Taming the shrew

    NASA Technical Reports Server (NTRS)

    Barlow, A.

    1990-01-01

    The pace of progress in the design of integrated circuits continues to amaze observers inside and outside of the industry. Three decades ago, a 50 transistor chip was a technological wonder. Fifteen year later, a 5000 transistor device would 'wow' the crowds. Today, 50,000 transistor chips will earn a 'not too bad' assessment, but it takes 500,000 to really leave an impression. In 1975 a typical ASIC device had 1000 transistors, took one year to first samples (and two years to production) and sold for about 5 cents per transistor. Today's 50,000 transistor gate array takes about 4 months from spec to silicon, works the first time, and sells for about 0.02 cents per transistor. Fifteen years ago, the single most laborious and error prone step in IC design was the physical layout. Today, most IC's never see the hand of a layout designer: and automatic place and route tool converts the engineer's computer captured schematic to a complete physical design using a gate array or a library of standard cells also created by software rather than by designers. CAD has also been a generous benefactor to the digital design process. The architect of today's digital systems creates the design using an RTL or other high level simulator. Then the designer pushes a button to invoke the logic synthesizer-optimizer tool. A fault analyzer checks the result for testability and suggests where scan based cells will improve test coverage. One obstinate holdout amidst this parade of progress is the automation of analog design and its reduction to semi-custom techniques. This paper investigates the application of CAD techniques to analog design.

  5. Nuclear organisation of some immunohistochemically identifiable neural systems in five species of insectivore-Crocidura cyanea, Crocidura olivieri, Sylvisorex ollula, Paraechinus aethiopicus and Atelerix frontalis.

    PubMed

    Calvey, Tanya; Patzke, Nina; Bennett, Nigel C; Consolate, Kaswera-Kyamakya; Gilissen, Emmanuel; Alagaili, Abdulaziz N; Mohammed, Osama B; Pettigrew, John D; Manger, Paul R

    2016-03-01

    The organization of the cholinergic, catecholaminergic, and serotonergic neurons in the brains of five species of insectivores and the orexinergic (hypocretinergic) system in four insectivore species is presented. We aimed to investigate the nuclear complement of these neural systems in comparison to those of other mammalian species. Brains of insectivores were coronally sectioned and immunohistochemically stained with antibodies against choline acetyltransferase, tyrosine hydroxylase, serotonin and orexin-A. The majority of nuclei were similar among the species investigated and to mammals in general, but certain differences in the nuclear complement highlighted potential phylogenetic interrelationships. In the cholinergic system, the three shrew species lacked parabigeminal and Edinger-Westphal nuclei. In addition, the appearance of the laterodorsal tegmental nucleus in all insectivores revealed a mediodorsal arch. All three of these features are the same as those present in microchiropterans. The catecholaminergic system of the three shrew species lacked the A4 and A15d nuclei, as well as having an incipient A9v nucleus, again features found in microchiropteran brains. The serotonergic and orexinergic systems of the insectivores are similar to those seen across most eutherian mammals. The analysis of similarities and differences across mammalian species indicates a potential phylogenetic relationship between the Soricidae (shrews) and the microchiropterans. PMID:26724499

  6. Mammalian genome projects reveal new growth hormone (GH) sequences. Characterization of the GH-encoding genes of armadillo (Dasypus novemcinctus), hedgehog (Erinaceus europaeus), bat (Myotis lucifugus), hyrax (Procavia capensis), shrew (Sorex araneus), ground squirrel (Spermophilus tridecemlineatus), elephant (Loxodonta africana), cat (Felis catus) and opossum (Monodelphis domestica).

    PubMed

    Wallis, Michael

    2008-01-15

    Mammalian growth hormone (GH) sequences have been shown previously to display episodic evolution: the sequence is generally strongly conserved but on at least two occasions during mammalian evolution (on lineages leading to higher primates and ruminants) bursts of rapid evolution occurred. However, the number of mammalian orders studied previously has been relatively limited, and the availability of sequence data via mammalian genome projects provides the potential for extending the range of GH gene sequences examined. Complete or nearly complete GH gene sequences for six mammalian species for which no data were previously available have been extracted from the genome databases-Dasypus novemcinctus (nine-banded armadillo), Erinaceus europaeus (western European hedgehog), Myotis lucifugus (little brown bat), Procavia capensis (cape rock hyrax), Sorex araneus (European shrew), Spermophilus tridecemlineatus (13-lined ground squirrel). In addition incomplete data for several other species have been extended. Examination of the data in detail and comparison with previously available sequences has allowed assessment of the reliability of deduced sequences. Several of the new sequences differ substantially from the consensus sequence previously determined for eutherian GHs, indicating greater variability than previously recognised, and confirming the episodic pattern of evolution. The episodic pattern is not seen for signal sequences, 5' upstream sequence or synonymous substitutions-it is specific to the mature protein sequence, suggesting that it relates to the hormonal function. The substitutions accumulated during the course of GH evolution have occurred mainly on the side of the hormone facing away from the receptor, in a non-random fashion, and it is suggested that this may reflect interaction of the receptor-bound hormone with other proteins or small ligands. PMID:17574247

  7. Complete mitochondrial genome sequence of Nectogale elegans.

    PubMed

    Huang, Ting; Yan, Chaochao; Tan, Zheng; Tu, Feiyun; Yue, Bisong; Zhang, Xiuyue

    2014-08-01

    The elegant water shrew (Nectogale elegans) belongs to the family Soricidae, and distributes in northern South Asia, central and southern China and northern Southeast Asia. In this study, the complete mitochondrial genome of N. elegans was sequenced. It was determined to be 17,460 bases, and included 13 protein-coding genes (PCGs), 22 tRNA genes, 2 ribosomal RNA genes and one non-coding region, which is similar to other mammalian mitochondrial genomes. Bayesian inference and maximum likelihood methods were used to construct phylogenetic trees based on 12 heavy-strand concatenated PCGs. Phylogenetic analyses further confirmed that Crocidurinae diverged prior to Soricinae, and Sorex unguiculatus differentiated earlier than N. elegans. PMID:23795853

  8. SHORT REPORT

    PubMed Central

    Gu, S. H.; Dormion, J.; Hugot, J.-P.; Yanagihara, R.

    2014-01-01

    SUMMARY Recent discovery of genetically distinct hantaviruses in shrews and moles (order Soricomorpha, family Soricidae and Talpidae) has challenged the conventional view that rodents serve as the principal reservoir hosts. Nova virus (NVAV), previously identified in archival liver tissue of a single European mole (Talpa europaea) from Hungary, represents one of the most highly divergent hantaviruses identified to date. To ascertain the spatial distribution and genetic diversity of NVAV, we employed RTPCR to analyse lungs from 94 moles, captured in two locations in France, during October 2012 to March 2013. NVAV was detected in more than 60% of moles at each location, suggesting efficient enzootic virus transmission and confirming that this mole species serves as the reservoir host. Although the pathogenic potential of NVAV is unknown, the widespread geographical distribution of the European mole might pose a hantavirus exposure risk for humans. PMID:24044372

  9. Arthritis in a glyptodont (Mammalia, Xenarthra, Cingulata).

    PubMed

    Barbosa, Fernando Henrique de Souza; Porpino, Kleberson de Oliveira; Fragoso, Ana Bernadete Lima; Oliveira, Edison Vicente

    2014-01-01

    Arthritic lesions have been frequently diagnosed in the fossil record, with spondyloarthropathy (a type of erosive and pan-mammalian arthritis) being one of the most common types described to date for mammals, though not restricted to this group. Here, we identify spondyloarthropathy in fossil bones from the late Pleistocene in Brazil assignable to a large glyptodont individual. Bone erosions in the peripheral joints (viz., the ulna, radius, left femur and tibiae-fibulae) associated with osteosclerosis allow the diagnosis of spondyloarthropathy. The presence of osteophytes in seven bones of the forelimbs (viz., the ulna and radius) and hind limbs (viz., the tibiae-fibulae, left femur and patellae) and a subchondral cyst in one element (viz., the left femur) indicate secondary osteoarthritis. A calcified deposition on the articular surface of the left patella indicates the presence of calcium pyrophosphate deposition disease, which, like the observed osteoarthritic alterations, likely represents a complication of spondyloarthropathy. This is the first report of spondyloarthropathy for xenarthrans. PMID:24551126

  10. Arthritis in a Glyptodont (Mammalia, Xenarthra, Cingulata)

    PubMed Central

    Barbosa, Fernando Henrique de Souza; Porpino, Kleberson de Oliveira; Fragoso, Ana Bernadete Lima; Oliveira, Edison Vicente

    2014-01-01

    Arthritic lesions have been frequently diagnosed in the fossil record, with spondyloarthropathy (a type of erosive and pan-mammalian arthritis) being one of the most common types described to date for mammals, though not restricted to this group. Here, we identify spondyloarthropathy in fossil bones from the late Pleistocene in Brazil assignable to a large glyptodont individual. Bone erosions in the peripheral joints (viz., the ulna, radius, left femur and tibiae-fibulae) associated with osteosclerosis allow the diagnosis of spondyloarthropathy. The presence of osteophytes in seven bones of the forelimbs (viz., the ulna and radius) and hind limbs (viz., the tibiae-fibulae, left femur and patellae) and a subchondral cyst in one element (viz., the left femur) indicate secondary osteoarthritis. A calcified deposition on the articular surface of the left patella indicates the presence of calcium pyrophosphate deposition disease, which, like the observed osteoarthritic alterations, likely represents a complication of spondyloarthropathy. This is the first report of spondyloarthropathy for xenarthrans. PMID:24551126

  11. Body size of Smilodon (Mammalia: Felidae).

    PubMed

    Christiansen, Per; Harris, John M

    2005-12-01

    The body masses of the three large saber-toothed machairodontines, Smilodon gracilis, S. fatalis, and S. populator, were estimated on the basis of 36 osteological variables from the appendicular skeleton of extant felids. A new model is introduced that takes the reliability of the predictor equations into account, since mass estimates are more reliable when computed from multiple variables per bone. At a body mass range of 55-100 kg, S. gracilis was comparable in size to extant jaguars, and S. fatalis was found to be somewhat lighter than previously assumed, with a body mass range of 160-280 kg, similar to that of the largest extant felid, the Siberian tiger. Smilodon populator was substantially heavier and larger than any extant felid, with a body mass range of 220-360 kg. Particularly large specimens of S. populator almost certainly exceeded 400 kg in body mass. The differences from previous estimates are most likely caused by differences in the databases used for mass estimation. PMID:16235255

  12. Phylogeny and life histories of the 'Insectivora': controversies and consequences.

    PubMed

    Symonds, Matthew R E

    2005-02-01

    The evolutionary relationships of the eutherian order Insectivora (Lipotyphla sensu stricto) are the subject of considerable debate. The difficulties in establishing insectivore phylogeny stem from their lack of many shared derived characteristics. The grouping is therefore something of a 'wastebasket' taxon. Most of the older estimates of phylogeny, based on morphological evidence, assumed insectivore monophyly. More recently, molecular phylogenies argue strongly against monophyly, although they differ in the extent of polyphyly inferred for the order. I review the history of insectivore phylogenetics and systematics, focussing on the relationships between the six extant families (Erinaceidae--hedgehogs and moonrats, Talpidae - moles and desmans, Soricidae - shrews, Solenodontidae--solenodons, Tenrecidae--tenrecs and otter-shrews and Chrysochloridae--golden moles). I then examine how these various phylogenetic hypotheses influence the results of comparative analyses and our interpretation of insectivore life-history evolution. I assess which particular controversies have the greatest effect on results, and discuss the implications for comparative analyses where the phylogeny is controversial. I also explore and suggest explanations for certain insectivore life-history trends: increased gestation length and litter size in tenrecs, increased encephalization in moles, and the mixed fast and slow life-history strategies in solenodons. Finally, I consider the implications for comparative analyses of the recent strongly supported phylogenetic hypothesis of an endemic African clade of mammals that includes the insectivore families of tenrecs and golden moles. PMID:15727040

  13. Evolution of sensory specializations in insectivores.

    PubMed

    Catania, Kenneth C

    2005-11-01

    Although insectivores have traditionally been thought of as primitive mammals with few specializations, recent studies have revealed great diversity in the sensory systems and brain organization of members of this mammalian order. The present article reviews some of these findings in three insectivore families that are thought to form a monophyletic group. These include hedgehogs (Erinaceidae), moles (Talpidae), and shrews (Soricidae). Members of each group live in unique ecological niches, have differently specialized senses, and exhibit different behaviors. Hedgehogs have well-developed visual, auditory, and somatosensory systems. Shrews make use of visual and auditory cues, but appear to depend most heavily on touch, particularly through prominent vibrissae. Moles are somatosensory specialists with small eyes and ears and unique epidermal mechanoreceptors called Eimer's organs used to identify prey and investigate their environment. In contrast to historical views of the insectivore order, members of this group have discrete and well-organized cortical sensory areas with sharp borders as determined from both electrophysiological mapping and analysis of cortical histology. Comparison of cortical organization across species reveals a number of specializations, including expansion of cortical representations of important sensory surfaces, the addition of cortical areas to some processing networks, and the subdivision of areas into separate cortical modules. In the case of the star-nosed mole, the somatosensory system has a tactile fovea and shares a number of features in common with the visual systems of sighted mammals. PMID:16215983

  14. Re-Teaching Shakespeare (II): The Shrew Oppressed.

    ERIC Educational Resources Information Center

    Williams, Michael

    1990-01-01

    Describes a "Shakespeare Coursework Unit" in which Shakespearean and other literary works of the Tudor era were analyzed for evidence of the gender biases prevalent in that period. Notes that by the end of the course, students accepted the assertion that textual analysis is never truly completed. (SG)

  15. On the development of the shoulder girdle in Crocidura russula (Soricidae) and other placental mammals: evolutionary and functional aspects.

    PubMed

    Grossmann, Martin; Snchez-Villagra, Marcelo R; Maier, Wolfgang

    2002-11-01

    The development of the shoulder girdle was studied in embryonic stages and a neonate of Crocidura russula using histological sections and 3-D reconstructions. Neonatal stages of Suncus etruscus and Mesocricetus auratus, both altricial placentals, were also studied. The earliest stage of C russula, in which the scapula is still partially blastematous, has already a supraspinous fossa. The dorsal portion of the scapular spine does not develop from the anterior margin of the scapula. Its mode of development varies among the placentals studied to date. In some it is completely appositional bone, in others it consists of bone formed mostly by endochondral ossification of a dorsal cartilaginous process stemming from the acromium. During development the supraspinatus muscle increases in size in proportion to the infraspinatus muscle and the humeral head increases in size in relation to the glenoid fossa. Placentals have secondary cartilage in the sternal and acromial ends of the clavicle, a derived feature absent in Marsupialia. Even the most altricial placentals have a more developed shoulder girdle at birth than any newborn marsupial studied to date. PMID:12448772

  16. On the development of the shoulder girdle in Crocidura russula (Soricidae) and other placental mammals: evolutionary and functional aspects

    PubMed Central

    Gromann, Martin; Snchez-Villagra, Marcelo R; Maier, Wolfgang

    2002-01-01

    The development of the shoulder girdle was studied in embryonic stages and a neonate of Crocidura russula using histological sections and 3-D reconstructions. Neonatal stages of Suncus etruscus and Mesocricetus auratus, both altricial placentals, were also studied. The earliest stage of C. russula, in which the scapula is still partially blastematous, has already a supraspinous fossa. The dorsal portion of the scapular spine does not develop from the anterior margin of the scapula. Its mode of development varies among the placentals studied to date. In some it is completely appositional bone, in others it consists of bone formed mostly by endochondral ossification of a dorsal cartilaginous process stemming from the acromium. During development the supraspinatus muscle increases in size in proportion to the infraspinatus muscle and the humeral head increases in size in relation to the glenoid fossa. Placentals have secondary cartilage in the sternal and acromial ends of the clavicle, a derived feature absent in Marsupialia. Even the most altricial placentals have a more developed shoulder girdle at birth than any newborn marsupial studied to date. PMID:12448772

  17. Ecological correlates to cranial morphology in Leporids (Mammalia, Lagomorpha)

    PubMed Central

    Sherratt, Emma; Bumacod, Nicholas; Wedel, Mathew J.

    2015-01-01

    The mammalian order Lagomorpha has been the subject of many morphometric studies aimed at understanding the relationship between form and function as it relates to locomotion, primarily in postcranial morphology. The leporid cranial skeleton, however, may also reveal information about their ecology, particularly locomotion and vision. Here we investigate the relationship between cranial shape and the degree of facial tilt with locomotion (cursoriality, saltation, and burrowing) within crown leporids. Our results suggest that facial tilt is more pronounced in cursors and saltators compared to generalists, and that increasing facial tilt may be driven by a need for expanded visual fields. Our phylogenetically informed analyses indicate that burrowing behavior, facial tilt, and locomotor behavior do not predict cranial shape. However, we find that variables such as bullae size, size of the splenius capitus fossa, and overall rostral dimensions are important components for understanding the cranial variation in leporids. PMID:25802812

  18. Convergence vs. Specialization in the ear region of moles (Mammalia).

    PubMed

    Crumpton, Nick; Kardjilov, Nikolay; Asher, Robert J

    2015-08-01

    We investigated if and how the inner ear region undergoes similar adaptations in small, fossorial, insectivoran-grade mammals, and found a variety of inner ear phenotypes. In our sample, afrotherian moles (Chrysochloridae) and the marsupial Notoryctes differ from most other burrowing mammals in their relatively short radii of semicircular canal curvature; chrysochlorids and fossorial talpids share a relatively long interampullar width. Chrysochlorids are unique in showing a highly coiled cochlea with nearly four turns. Extensive cochlear coiling may reflect their greater ecological dependence on low frequency auditory cues compared to talpids, tenrecids, and the marsupial Notoryctes. Correspondingly, the lack of such extensive coiling in the inner ear of other fossorial species may indicate a greater reliance on other senses to enable their fossorial lifestyle, such as tactile sensation from vibrissae and Eimer's organs. The reliance of chrysochlorids on sound is evident in the high degree of coiling and in the diversity of its mallear types, and may help explain the lack of any semiaquatic members of that group. The simplest mallear types among chrysochlorids are not present in the basal-most members of that clade, but all extant chrysochlorids investigated to date exhibit extensive cochlear coiling. The chrysochlorid ear region thus exhibits mosaic evolution; our data suggest that extensive coiling evolved in chrysochlorids prior to and independently of diversification in middle ear ossicle size and shape. PMID:25858660

  19. Generic names of northern and southern fur seals (Mammalia: Otariidae)

    USGS Publications Warehouse

    Gardner, A.L.; Robbins, C.B.

    1998-01-01

    We have resolved a nomenclatural problem discovered during research on the northern fur seal that concerns the correct generic name for this taxon and for fur seals of the Southern Hemisphere. The unfortunate practice by some 19th century authors to use names in their Latinized form, but to date them from their first appearance as French common names led to the use of Arctocephalus for southern fur seals when the name correctly applies to the northern fur seal, known today as Callorhinus ursinus. However, Arctocephalus and Callorhinus are antedated by Otoes G. Fischer, 1817, which is the earliest available generic for the fur seal of the northern Pacific. The earliest available generic name for southern fur seals is Halarctus Gill, 1866. To avoid the confusion that would result from replacing the currently used generic names with those required by strict adherence to the Principle of Priority, we have petitioned the International Commission on Zoological nomenclature to preserve Arctocephalus and Callorhinus for the southern and northern fur seals, respectively.

  20. Molecular evolution of Holarctic martens (genus Martes, Mammalia: Carnivora: Mustelidae).

    PubMed

    Stone, Karen D; Cook, Joseph A

    2002-08-01

    The Bering Land Bridge has served as a major corridor of interchange between the northern continents for many organisms. We investigated the phylogeny of all extant species of Martes (except for Martes gwatkinsi from India) to infer evolutionary relationships and characterize the extent of trans-Beringian movements. Analyses of complete sequences of the mitochondrial cytochrome b gene and partial sequences of the nuclear aldolase C gene (241bp) suggested that the genus Martes may be paraphyletic with respect to Gulo gulo. These data supported the fossil record's indication that early radiations gave rise to two subgenera (Pekania and Charronia) and that a more recent, possibly rapid, radiation gave rise to species of the third subgenus (Martes). Two colonizations of North America are evident, one by members of the subgenus Pekania and another by member of the subgenus Martes. Contrary to hypotheses based on morphological evidence, the "americana" and "caurina" subspecies groups of Martes americana are not the result of independent colonizations of North America. The phylogenetic analyses of cytochrome b data were consistent with the recognition of these subspecies groups as monophyletic clades; however, variation in the aldolase C sequences indicated that these generally parapatric groups may interbreed in a region of limited geographic overlap. PMID:12144754

  1. Eocene archaeohyracids (Mammalia: Notoungulata: Hegetotheria) from the Puna, northwest Argentina

    NASA Astrophysics Data System (ADS)

    Reguero, Marcelo A.; Croft, Darin C.; Lpez, Guillermo M.; Alonso, Ricardo N.

    2008-09-01

    A new genus and species of basal hegetothere mammal, Punahyrax bondesioi, is described from the middle-late? Eocene Geste Formation of northwestern (Catamarca and Salta provinces) Argentina. The new species is based on isolated teeth and mandibles and represents the first well-identified archaeohyracid from northwestern Argentina, and the earliest extra-Patagonian record of the family. It is characterized by its small-size and a short talonid on the molars. Though still poorly documented, this new taxon may provide key-data for the problem of the origin and basal of hegetotheres phylogeny. These fossils show the importance of northwestern Argentina (Puna area) in the early evolution of the extinct order Notoungulata and the poor state of our knowledge there.

  2. A Reexamination of the Carnivora Malleus (Mammalia, Placentalia)

    PubMed Central

    Wible, John R.; Spaulding, Michelle

    2012-01-01

    Authoritative anatomical references depict domestic dogs and cats as having a malleus with a short rostral (anterior) process that is connected via a ligament to the ectotympanic of the auditory bulla. Similar mallei have been reported for representatives of each of the 15 extant families of Carnivora, the placental order containing dogs and cats. This morphology is in contrast to a malleus with a long rostral process anchored to the ectotympanic that is considered to be primitive for mammals. Our reexamination of extant carnivorans found representatives from 12 families that possess an elongate rostral process anchored to the ectotympanic. Consequently, the malleus also is a component of the bulla. In a subset of our carnivoran sample, we confirmed that the elongate rostral process on the ectotympanic is continuous with the rest of the malleus through a thin osseous lamina. This morphology is reconstructed as primitive for Carnivora. Prior inaccurate descriptions of the taxa in our sample having mallei continuous with the bulla were based on damaged mallei. In addition to coupling to the ectotympanic, the rostral process of the malleus was found to have a hook-like process that fits in a facet on the skull base in representatives from seven families (felids, nandiniids, viverrids, canids, ursids, procyonids, and mustelids); its occurrence in the remaining families could not be ascertained. This feature is named herein the mallear hook and is likewise reconstructed to be primitive for Carnivora. We also investigated mallei in one additional placental order reported to have mallei not connected to the ectotympanic, Pholidota (pangolins), the extant sister group of Carnivora. We found pholidotans to also have anchored mallei with long rostral processes, but lacking mallear hooks. In light of our results, other mammals previously reported to have short rostral processes should be reexamined. PMID:23209753

  3. Comparison of mitochondrial genome sequences of pangolins (Mammalia, Pholidota).

    PubMed

    Hassanin, Alexandre; Hugot, Jean-Pierre; van Vuuren, Bettine Jansen

    2015-04-01

    The complete mitochondrial genome was sequenced for three species of pangolins, Manis javanica, Phataginus tricuspis, and Smutsia temminckii, and comparisons were made with two other species, Manis pentadactyla and Phataginus tetradactyla. The genome of Manidae contains the 37 genes found in a typical mammalian genome, and the structure of the control region is highly conserved among species. In Manis, the overall base composition differs from that found in African genera. Phylogenetic analyses support the monophyly of the genera Manis, Phataginus, and Smutsia, as well as the basal division between Maninae and Smutsiinae. Comparisons with GenBank sequences reveal that the reference genomes of M. pentadactyla and P. tetradactyla (accession numbers NC_016008 and NC_004027) were sequenced from misidentified taxa, and that a new species of tree pangolin should be described in Gabon. PMID:25746396

  4. Sensory Hairs in the Bowhead Whale, Balaena mysticetus (Cetacea, Mammalia).

    PubMed

    Drake, Summer E; Crish, Samuel D; George, John C; Stimmelmayr, Raphaella; Thewissen, J G M

    2015-07-01

    We studied the histology and morphometrics of the hairs of bowhead whales (Balaena mysticetus). These whales are hairless except for two patches of more than 300 hairs on the rostral tip of the lower lip and chin, the rostral tip of the upper lip, and a bilateral row of approximately ten hairs caudal to the blowhole. Histological data indicate that hairs in all three of these areas are vibrissae: they show an outermost connective tissue capsule, a circumferential blood sinus system surrounding the hair shaft, and dense innervation to the follicle. Morphometric data were collected on hair diameters, epidermal recess diameters, hair follicle length, and external hair lengths. The main difference between the hairs in the different regions is that blowhole hairs have larger diameters than the hairs in the chin and rostrum regions. We speculate that the hair shaft thickness patterns in bowheads reflect functional specializations. PMID:25869730

  5. Helminths of three species of opossums (Mammalia, Didelphidae) from Mexico

    PubMed Central

    Acosta-Virgen, Karla; López-Caballero, Jorge; García-Prieto, Luis; Mata-López, Rosario

    2015-01-01

    Abstract From August 2011 to November 2013, 68 opossums (8 Didelphis sp., 40 Didelphis virginiana, 15 Didelphis marsupialis, and 5 Philander opossum) were collected in 18 localities from 12 Mexican states. A total of 12,188 helminths representing 21 taxa were identified (6 trematodes, 2 cestodes, 3 acanthocephalans and 10 nematodes). Sixty-six new locality records, 9 new host records, and one species, the trematode Brachylaima didelphus, is added to the composition of the helminth fauna of the opossums in Mexico. These data, in conjunction with previous records, bring the number of taxa parasitizing the Mexican terrestrial marsupials to 41. Among these species, we recognized a group of helminths typical of didelphids in other parts of the Americas. This group is constituted by the trematode Rhopalias coronatus, the acanthocephalan Oligacanthorhynchus microcephalus and the nematodes Cruzia tentaculata, Gnathostoma turgidum, and Turgida turgida. In general, the helminth fauna of each didelphid species showed a stable taxonomic composition with respect to previously sampled sites. This situation suggests that the rate of accumulation of helminth species in the inventory of these 3 species of terrestrial marsupials in the Neotropical portion of Mexico is decreasing; however, new samplings in the Nearctic portion of this country will probably increase the richness of the helminthological inventory of this group of mammals. PMID:26257556

  6. Helminths of three species of opossums (Mammalia, Didelphidae) from Mexico.

    PubMed

    Acosta-Virgen, Karla; López-Caballero, Jorge; García-Prieto, Luis; Mata-López, Rosario

    2015-01-01

    From August 2011 to November 2013, 68 opossums (8 Didelphis sp., 40 Didelphisvirginiana, 15 Didelphismarsupialis, and 5 Philanderopossum) were collected in 18 localities from 12 Mexican states. A total of 12,188 helminths representing 21 taxa were identified (6 trematodes, 2 cestodes, 3 acanthocephalans and 10 nematodes). Sixty-six new locality records, 9 new host records, and one species, the trematode Brachylaimadidelphus, is added to the composition of the helminth fauna of the opossums in Mexico. These data, in conjunction with previous records, bring the number of taxa parasitizing the Mexican terrestrial marsupials to 41. Among these species, we recognized a group of helminths typical of didelphids in other parts of the Americas. This group is constituted by the trematode Rhopaliascoronatus, the acanthocephalan Oligacanthorhynchusmicrocephalus and the nematodes Cruziatentaculata, Gnathostomaturgidum, and Turgidaturgida. In general, the helminth fauna of each didelphid species showed a stable taxonomic composition with respect to previously sampled sites. This situation suggests that the rate of accumulation of helminth species in the inventory of these 3 species of terrestrial marsupials in the Neotropical portion of Mexico is decreasing; however, new samplings in the Nearctic portion of this country will probably increase the richness of the helminthological inventory of this group of mammals. PMID:26257556

  7. Trends of karyotypic evolution in the genus Hipposideros (Chiroptera: Mammalia).

    PubMed

    Sreepada, K S; Naidu, K N; Gururaj, M E

    1993-01-01

    The karyotypes of Hipposideros speroris, H. pomona, H. lankadiva, H. ceneraceus, H. ater and H. fulvus were analysed using conventional and banding technqiues. All six species exhibited the same 2n (32) and FN (60). The genus is remarkable for its apparent karyotypic stability. These species have only biarmed autosomes, one of which is a submetacentric marker chromosome with an achromatic gap. G-banded autosomes showed that most have remained conservative in the course of evolution of the species. Structural changes seemed to have occurred more frequently in the sex elements of the karyotypes rather than in the autosomes, and non-Robertsonian changes had an appreciable role to play in karyotypic evolution. This trend is probably dictated by the maximization of the biarmed condition which reflects the formation of stabilised linkage groups from the inception of the genus. It is proposed that the ancestral lineage of the genus Hipposideros was derived from a Rhinolophoid ancester whose karyotype was akin to Rhinolophus luctus. PMID:8375193

  8. Nitrogen requirements of white-lipped peccary (Mammalia, Tayassuidae).

    PubMed

    Nogueira-Filho, Srgio L G; Borges, Rogrio M; Mendes, Alcester; Dias, Carlos T S

    2014-01-01

    A study was conducted to determine the protein requirement of the white-lipped peccary (Tayassu pecari) performing a nitrogen (N) balance digestion trial. In a 4??4 Latin square design, four adult captive male peccaries were fed four isoenergetic diets containing four different levels of N (13.3, 19.2, 28.7, and 37.1?g?N/kg dry matter). After 15 days of adaptation, the total collection of feces and urine was carried out for five consecutive days. By regression analysis between N intake and N in feces and urine, the metabolic fecal nitrogen (MFN?=?3.1?g/kg of dry matter intake) and daily endogenous urinary N (EUN?=?91.0?mg/kg(0.75) ) were determined. Likewise, by regression analyses between consumption of nitrogen and the nitrogen balance [NB?N consumed-(fecal N?+?Urine N)] we estimated the daily requirement of 336.5 mgN/kg(0.75) . Therefore, if food intake is unrestricted, white-lipped peccaries require a minimum content in their diet of about 4.5% crude protein as percentage of dry diet. These values are similar to those found in frugivorous wild ruminants, which reinforces the proposition that peccaries have a digestive physiology nearer to that of ruminants than of domestic pigs. Furthermore, the low nutritional maintenance requirements for white-lipped peccary may explain how this species thrive in the Neo-tropical region eating predominantly palm-fruits that normally have low crude protein contents. PMID:24958733

  9. Vertebral anomaly in fossil sea cows (Mammalia, Sirenia).

    PubMed

    Voss, Manja; Asbach, Patrick; Hilger, Andr

    2011-06-01

    Four incompletely preserved caudal vertebrae lacking the neural arches of two fossil sirenian individuals of Halitherium schinzii (Oligocene) from the Rhine area in Germany and northern Belgium reveal osteological alterations. The caudal vertebrae possess a transverse process with growth retardation. This asymmetry indicates that the affected transverse processes are less developed than their counterparts and, consequently, deviate from the norm. Computed tomography (CT) scans reveal osteosclerotic patterns, a morphological feature that characterizes sea cows and supports the nonpathological state of the vertebrae. Additionally, no indications of vertebral fractures or any other occurrences due to external factors are present. This is the oldest documentation of such an anomaly in any sirenian and is interpreted here as hypoplasia, the underdevelopment of an organ or parts of it that might cause a functional deficiency. PMID:21538937

  10. Breaking constraint: axial patterning in Trichechus (Mammalia: Sirenia).

    PubMed

    Buchholtz, Emily A; Wayrynen, Kaisa L; Lin, Iris W

    2014-01-01

    Meristic variation is often limited in serially homologous systems with high internal differentiation and high developmental modularity. The mammalian neck, an extreme example, has a fixed (at seven) count of diversely specialized segments. Imposition of the mammalian cervical constraint has been tentatively linked to the origin of the diaphragm, which is muscularized by cells that migrate from cervical somites during development. With six cervical vertebrae, the genus Trichechus (manatee) has apparently broken this constraint, although the mechanism of constraint escape is unknown. Hypotheses for the developmental origin of Trichechus cervical morphology include cervical rib 7 repatterning, a primaxial/abaxial patterning shift, and local homeosis at the cervical/thoracic boundary. We tested predictions of these hypotheses by documenting vertebral morphology, axial ossification patterns, regionalization of the postcranial skeleton, and the relationship of thoracic ribs to sternal subunits in a large data set of fetal and adult Trichechus and Dugong specimens. These observations forced rejection of all three hypotheses. We propose alternatively that a global slowing of the rate of somitogenesis reduced somite count and disrupted alignment of Hox-generated anatomical markers relative to somite (and vertebral) boundaries throughout the Trichechus column. This hypothesis is consistent with observations of the full range of traditional cervical morphologies in the six cervical vertebrae, conserved postcranial proportions, and column-wide reduction in count relative to its sister taxon, Dugong. It also suggests that the origin of the mammalian cervical constraint lies in patterning, not in count, and that Trichechus and the tree sloths have broken the constraint using different developmental mechanisms. PMID:25339599

  11. Morphology and environment in some fossil Hominoids and Pedetids (Mammalia).

    PubMed

    Senut, Brigitte

    2016-04-01

    Linking the environment to functional anatomy is not an easy exercise, especially when dealing with fossils, which are often fragmentary and represent animals that are extinct. A holistic approach permits us to fill the gaps in reconstructing the evolutionary patterns in fossil groups. Identifying the environment where animals lived can help to interpret some anatomical structures and, vice versa, the functional morphological pattern can help to refine some fossil environments. Two examples focusing on locomotor behaviours in fossil mammals are considered in this paper: the hominoids and the origins of hominid bipedalism and the springing adaptations in fossil rodents (Pedetidae) in connection with different habitats. In the first case, the limits of the chimp-based models and the necessity to take into account detailed environmental reconstructions will be addressed. The famous 'savannah hypothesis' is no longer tenable because the palaeontological data support a more vegetated environment for the origins of bipedal hominids. Data from the environment will be considered. The earliest putative hominid fossils which preserve skeletal remains of the locomotor apparatus show mixed adaptations to terrestrial bipedalism and arboreal activities. The second example focuses on the variation in springing adaptations in Pedetidae in the Lower Miocene of East Africa and Southern Africa. In the East, the sites where Pedetidae were preserved were mainly forested, whereas in the South the region was more open and drier, with extensive grassy patches. In the first case, pedetids were robust and heavy jumpers, whereas in the South they were smaller, their skeleton more gracile and their springing was lighter. During the desertification of the southern part of Africa, the large pedetid species became extinct, but a smaller species developed. In the case of primates, as in the case of rodents, the skeletal morphology was adapted to its environment. PMID:26712383

  12. Shared ancestry between a newfound mole-borne hantavirus and hantaviruses harbored by cricetid rodents.

    PubMed

    Kang, Hae Ji; Bennett, Shannon N; Hope, Andrew G; Cook, Joseph A; Yanagihara, Richard

    2011-08-01

    Discovery of genetically distinct hantaviruses in multiple species of shrews (order Soricomorpha, family Soricidae) and moles (family Talpidae) contests the conventional view that rodents (order Rodentia, families Muridae and Cricetidae) are the principal reservoir hosts and suggests that the evolutionary history of hantaviruses is far more complex than previously hypothesized. We now report on Rockport virus (RKPV), a hantavirus identified in archival tissues of the eastern mole (Scalopus aquaticus) collected in Rockport, TX, in 1986. Pairwise comparison of the full-length S, M, and L genomic segments indicated moderately low sequence similarity between RKPV and other soricomorph-borne hantaviruses. Phylogenetic analyses, using maximum-likelihood and Bayesian methods, showed that RKPV shared a most recent common ancestor with cricetid-rodent-borne hantaviruses. Distributed widely across the eastern United States, the fossorial eastern mole is sympatric and syntopic with cricetid rodents known to harbor hantaviruses, raising the possibility of host-switching events in the distant past. Our findings warrant more-detailed investigations on the dynamics of spillover and cross-species transmission of present-day hantaviruses within communities of rodents and moles. PMID:21632770

  13. Hylomysobia gen. n. (Acari: Myobiidae), a new genus of mites parasitic on gymnures of the genus Hylomys (Eulipotyphla: Erinaceidae).

    PubMed

    Bochkov, Andre V; OConnor, Barry M

    2006-12-01

    A new genus of Myobiidae, Hylomysobia gen. n. with two new species, H. mikhailzaitzevi sp. n. (type species) and H. chinensis sp. n., is described from gymnures of the genus Hylomys Müller (Eulipotyphla: Erinaceidae). The two species parasitize Hylomys suillus Müller from Cambodia and Vietnam, and Hylomys sinensis (Trouessart) from China, respectively. These species represent the first records of myobiid mites from species in the family Erinaceidae. The new genus differs from the closely related Eutalpacarus Jameson, 1949 by the following features: in both sexes, coxae I have a triangular process, setae ve are about three times wider than sce and c2, and coxae II bear two pairs of setae; in females, setae sci are lanceolate, setae ag1 and ag3 are absent, and the vulvar lobes are weakly developed; in males, setae e2 are absent, and setae c1, d1, d2 and e1 are situated on the genital shield. The life cycle of Hylomysobia spp. includes egg, larva, protonymph, deutonymph, and adults, male and female. In contrast to the most other myobiid genera possessing the tritonymphal stage, the deutonymphs of Hylomysobia moult directly to adults, and the tritonymphs are absent. Based on the restricted distribution of Hylomysobia species on hosts of this family (only on species of the genus Hylomys) and close morphological similarities to myobiids from Soricidae and Talpidae, it is suggested that the ancestor of this genus secondarily colonized the ancestor of Hylomys from moles or shrews. PMID:17252925

  14. The Fleas of Endemic and Introduced Small Mammals in Central Highland Forests of Madagascar: Faunistics, Species Diversity, and Absence of Host Specificity.

    PubMed

    Goodman, Steven M; Randrenjarison Andriniaina, H Rico; Soarimalala, Voahangy; Beaucournu, Jean-Claude

    2015-09-01

    Data are presented on the flea species of the genera Paractenopsyllus (Ceratophyllidae, Leptopsyllinae) and Synopsyllus (Pulicidae, Xenopsyllinae) obtained from small mammals during two 2014 seasonal surveys at a montane humid forest site (Ambohitantely) in the Central Highlands of Madagascar. The mammal groups included the endemic family Tenrecidae (tenrecs) and subfamily Nesomyinae (rodents) and two introduced families Muridae (rodents) and Soricidae (shrews); no fleas were recovered from the latter family. The surveys were conducted at the end of the wet and dry seasons with 288 individual small mammals captured, including 12 endemic and four introduced species. These animals yielded 344 fleas, representing nine species endemic to Madagascar; no introduced species was collected. Some seasonal variation was found in the number of trapped small mammals, but no marked difference was found in species richness. For flea species represented by sufficient samples, no parasite-host specificity was found, and there is evidence for considerable lateral exchange in the local flea fauna between species of tenrecs and the two rodent families (endemic and introduced). The implications of these results are discussed with regards to small mammal species richness and community structure, as well as a possible mechanism for the maintenance of sylvatic cycles of bubonic plague in the montane forests of Madagascar. PMID:26336252

  15. Long-term effects of precommercial thinning on small mammals in northern Maine

    USGS Publications Warehouse

    Homyack, J.A.; Harrison, D.J.; Krohn, W.B.

    2005-01-01

    Precommercial thinning (PCT) is being practiced increasingly throughout the Acadian forest of eastern North America to meet silvicultural objectives; however, effects of this practice on wildlife, both immediately and several years post-treatment are not well understood. Forest dependent small mammals have ecological roles as prey for numerous avian and mammalian predators, dispersers of seeds, fruit, and spores, and contribute to nutrient cycling. Researchers in the northwestern USA have suggested that thinning of young, regenerating clearcuts may increase the abundance and diversity of some forest-dependent small mammals by increasing rates of forest development and enhancing the ecological representation of mid-successional stands across managed landscapes. We examined the effects of PCT within conifer-dominated forest stands 1-, 6-, 11-, and 16-years post-treatment, on abundances of mice, voles, and shrews, and on within-stand structure in the commercially managed, Acadian forests of northern Maine. We live-trapped small mammals on 24 herbicide-treated clearcuts treated with PCT and on 13 similar, unthinned stands during summers of 2000 and 2001. Thinning of mid-successional conifer stands resulted in increased abundances, (red-backed voles, Clethrionomys gapperi, P = 0.008; masked shrews, Sorex cinereus, P < 0.001) or had no detectable effect on (deer mice, Peromyscus maniculatus, P = 0.544; short-tailed shrews, Blarina brevicauda, P = 0.517) the 4 most common species of Muridae and Soricidae in northern Maine. In general, abundance of deer mice responded more positively to increasing development class and to the number of years since thinning than other species of small mammals. Several within-stand habitat characteristics associated with stand maturity, such as larger stem diameters and a partially open canopy, occurred in thinned stands. Thus, PCT may accelerate the development of habitat attributes typical of mid-successional conifer stands in intensively managed stands within the Acadian Forest. PCT may increase abundances of small mammal species associated with mid-seral forest conditions at the scale of the forest stand. ?? 2004 Elsevier B.V. All rights reserved.

  16. Fine structure of the parotid gland in tree shrew (Tupaia glis).

    PubMed

    Suzuki, S; Mifune, H; Nishida, T; Obara, T; Kamimura, R; Sakamoto, H; Mohammad Abdul, A; Nishinakagawa, H

    1995-10-01

    The parotid glands of Tupaia glis were examined by light and transmission electron microscopy. The acinar cells were seromucous in nature, and contained many acidophilic granules with strong affinity for periodic acid-Schiff (PAS) and weak affinity for alcian blue (AB). These granules consisted of a fine granular matrix of moderate density in which a denser corpuscles or semilunar materials were present. Intercalated duct cells had a few fine vesicles, vacuoles and very few dense granules in the apical region. In occasional epithelial cells, acidophilic, PAS-positive and AB-negative bodies with moderate density were observed in the supranuclear region. The striated ducts consisted of columnar light and dark cells containing round or small ovoid granules of moderate density and did not show the granular duct as seen in the parotid glands of kobe mole and tenrec which are placed in the order insectivora. PMID:8575539

  17. Scleral gene expression during recovery from myopia compared with expression during myopia development in tree shrew

    PubMed Central

    Guo, Lin; Frost, Michael R.; Siegwart, John T.

    2014-01-01

    Purpose During postnatal refractive development, the sclera receives retinally generated signals that regulate its biochemical properties. Hyperopic refractive error causes the retina to produce GO signals that, through the direct emmetropization pathway, cause scleral remodeling that increases the axial elongation rate of the eye, reducing the hyperopia. Myopia causes the retina to generate STOP signals that produce scleral remodeling, slowing the axial elongation rate and reducing the myopia. Our aim was to compare the pattern of gene expression produced in the sclera by the STOP signals with the GO gene expression signature we described previously. Methods The GO gene expression signature was produced by monocular 5 diopter (D) lens wear for 2 days (ML-2) or 4 days (ML-4); an additional STAY condition was examined after eyes had fully compensated for a 5 D lens after 11 days of lens wear (ML-11). After 11 days of ?5 D lens wear had produced full refractive compensation, gene expression in the STOP condition was examined during recovery (without the lens) for 2 days (REC-2) or 4 days (REC-4). The untreated contralateral eyes served as a control in all groups. Two age-matched normal groups provided a comparison with the treated groups. Quantitative real-time PCR was used to measure mRNA levels for 55 candidate genes. Results The STAY group compensated fully for the lens (treated eye versus control eye, 5.10.2 D). Wearing the lens, the hyperopic signal for elongation had dissipated (0.30.3 D). In the STOP groups, the refraction in the recovering eyes became less myopic relative to the control eyes (REC-2, +1.30.3 D; REC-4, +2.60.4 D). In the STAY group, three genes showed significant downregulation. However, many genes that were significantly altered in GO showed smaller, nonsignificant, expression differences in the same direction in STAY, suggesting the gene expression signature in STAY is a greatly weakened form of the GO signature. In the STOP groups, a different gene expression pattern was observed, characterized by mostly upregulation with larger fold differences after 4 days than after 2 days of recovery. Eleven of the 55 genes examined showed significant bidirectional GO/STOP regulation in the ML-2 and REC-2 groups, and 13 genes showed bidirectional regulation in the ML-4 and REC-4 groups. Eight of these genes (NPR3, CAPNS1, NGEF, TGFB1, CTGF, NOV, TIMP1, and HS6ST1) were bidirectionally regulated at both time points in the GO and STOP conditions. An additional 15 genes showed significant regulation in either GO or STOP conditions but not in both. Conclusions Many genes are involved in scleral remodeling and the control of axial length. The STOP (recovery) gene expression signature in the sclera involves some of the same genes, bidirectionally regulated, as the GO signature. However, other genes, regulated in GO, are not differentially regulated in STOP, and others show differential regulation only in STOP. PMID:25540576

  18. The use of albendazole for the treatment of trematodiasis in two tree shrews (Tupala glis)

    USGS Publications Warehouse

    Beehler, B.A.; Tuggle, B.N.

    1983-01-01

    Albendazole is a broad-spectrum anthelmintic of the benzimidazole group which has been tested in several rodents and domestic animals. Albendazole has been used effectively to treat trematodes in sheep, cattle, dogs, and cats. The use of this anthelmintic in exotic small mammals has not been reported to the authors' knowledge.

  19. Metabolomic analysis of key regulatory metabolites in hepatitis C virus-infected tree shrews.

    PubMed

    Sun, Hui; Zhang, Aihua; Yan, Guangli; Piao, Chengyu; Li, Weiyun; Sun, Chang; Wu, Xiuhong; Li, Xinghua; Chen, Yun; Wang, Xijun

    2013-03-01

    Metabolomics is a powerful new technology that allows the assessment of global low-molecular-weight metabolites in a biological system and which shows great potential in biomarker discovery. Analysis of the key metabolites in body fluids has become an important part of improving the diagnosis, prognosis, and therapy of diseases. Hepatitis C virus (HCV) is a major leading cause of liver disease worldwide and a serious burden on public health. However, the lack of a small-animal model has hampered the analysis of HCV pathogenesis. We hypothesize that an animal model (Tupaia belangeri chinensis) of HCV would produce a unique characterization of metabolic phenotypes. Ultra-performance liquid-chromatography/electrospray ionization-SYNAPT-high-definition mass spectrometry (UPLC/ESI-SYNAPT-HDMS) coupled with pattern recognition methods and system analysis was carried out to obtain comprehensive metabolomics profiling and pathways of large biological data sets. Taurine, hypotaurine, ether lipid, glycerophospholipid, arachidonic acid, tryptophan, and primary bile acid metabolism pathways were acutely perturbed, and 38 differential metabolites were identified. More important, five metabolite markers were selected via the "significance analysis for microarrays" method as the most discriminant and interesting biomarkers that were effective for the diagnosis of HCV. Network construction has led to the integration of metabolites associated with the multiple perturbation pathways. Integrated network analysis of the key metabolites yields highly related signaling pathways associated with the differentially expressed proteins, which suggests that the creation of new treatment paradigms targeting and activating these networks in their entirety, rather than single proteins, might be necessary for controlling and treating HCV efficiently. PMID:23264353

  20. Response to Interrupted Hyperopia after Restraint of Axial Elongation in Tree Shrews

    PubMed Central

    Siegwart, John T.; Norton, Thomas T.

    2012-01-01

    Purpose To determine if early restraint of axial elongation in response to plus lenses increases the subsequent response to interrupted hyperopia. Methods The normal, interrupted hyperopia group (n=5) had normal visual exposure until 24 days of visual experience (VE). Then, from 24 to 45 days of VE, the animals wore binocular ?4 D lenses which shifted the refractive state of the eyes in the direction of hyperopia. Interrupted hyperopia was produced by removing the lenses for 2 hours per day. The early restraint, interrupted hyperopia group (n=5) wore binocular +4 D lenses continuously from 11 to 24 days of VE, becoming emmetropic with the lenses in place and hyperopic when they were removed. Then, from 24 to 45 days of VE, the lenses were removed 22 hours per day and replaced for 2 hours per day. This created the same initial regimen of interrupted hyperopia as in the normal, interrupted hyperopia group. A plus-lens control group wore binocular +4 D lenses (n=5) continuously from 11 to 45 Days of VE to assess the stability of the refractive compensation. Results In the normal, interrupted hyperopia animals, 2 hours of relief from the imposed hyperopia was sufficient to prevent myopia development. In the early restraint, interrupted hyperopia animals, 2 hours of relief from the hyperopia did not prevent myopia development; the eyes became myopic while wearing the lens. The control animals compensated for the +4 D lenses and maintained a stable with-the-lens emmetropia through 45 days of VE, demonstrating that the myopic shift in the early-restraint group was due to the interrupted hyperopia. Conclusions Compensation for plus lenses, involving slowed axial elongation, increases the response to subsequent interrupted hyperopia. Similar to previous reports of an eye-size factor in elongated eyes, these data provide evidence for an eye-size mechanism operating, in this case, in eyes that have restrained their axial length. PMID:23314128

  1. Comparative aspects of lipid metabolism in two shrews (Suncus etruscus and Crocidura russula).

    PubMed

    Sicart, R; Sable-Amplis, R; Fons, R

    1978-01-01

    1. The amounts of tissue lipids were higher in S. etruscus than in C. russula. 2. The level of liver phospholipids was specially low in C. russula, 2650 mg/100 g as opposed to 3725 g in S. etruscus. 3. This is in good agreement with a reduced rate of the labelled acetate incorporation into the lipids of C. russula. 4. The proportion of unsaturated fatty acids was greater in the liver of S. etruscus; however, the percentage of arachidonic acid was higher in C. russula--15% as opposed to 8%. PMID:318366

  2. Blood oxygen transport and organ weights of two shrew species (S. etruscus and C. russula).

    PubMed

    Bartels, H; Bartels, R; Baumann, R; Fons, R; Jrgens, K D; Wright, P

    1979-03-01

    Blood parameters concerning oxygen transport and relative organ weights of 11 Suncus etruscus and 13 Crocidura russula under light halothane anesthesia were investigated. Mean body weight of S. etruscus was 2.5 g and for C. russula was 9 g, hemoglobin concentration was 17.4 and 15.6 g/100 ml blood, hematocrit was 50 and 44%, red blood cells were 18 and 11 X 10(6)/microliter, respectively. Mean corpuscular volume was calculated to be 26 and 41 micron3, mean diameter 5.5 and 7 micron, and mean thickness 1.2 and 1.1 micron, respectively. Mean corpuscular hemoglobin concentration was in the normal range of mammalian red blood cells. A blood oxygen half-saturation pressure of 35 and 34 Torr at pH 7.4, 37 degrees C and a Bohr factor deltalog P50/deltapH of -0.61 and -0.66 was measured. Experiments with stripped hemoglobin showed that 2,3-diphosphoglycerate is the main oxygen affinity reducing allosteric factor. Relative weights of heart, kidney, and liver are remarkably high in S. etruscus. The maximal oxygen transport of 400 ml . kg-1 . min-1 of S. etruscus is feasible by an enormous heart rate, a large relative stroke volume, a high hemoglobin concentration combined with a low oxygen affinity, and a large Bohr effect. PMID:426099

  3. TOXICITY EVALUATION OF 1,3,5-TRINITROBENZENE (TNB) IN SHREWS (CRYPTOTIS PARVA)

    EPA Science Inventory

    TNB has been detected as an environmental contaminant of soil and water at certain Army installations and production waste disposal sites. At present there are no toxicity data on TNB in small wild mammals that might be used for ecological risk assessment. Therefore, a 14-day to...

  4. Geographic and host range of the nematode Soboliphyme baturini across Beringia.

    PubMed

    Koehler, Anson V A; Hoberg, Eric P; Dokuchaev, Nikolai E; Cook, Joseph A

    2007-10-01

    The nematode Soboliphyme baturini Petrov, 1930, was found to represent a single species with a relatively broad geographic range across Beringia and northwestern North America on the basis of the assessment of molecular sequence data for adult and juvenile parasites. Refuted are hypotheses suggesting that several cryptic species could be partitioned either among an array of mustelid definitive hosts or across the vast region that links North America and Eurasia. Host specificity for this species is examined on the basis of a comprehensive list for definitive hosts, derived from new field surveys and existing literature for S. baturini. Only 5 mustelids (Gulo gulo, Martes americana, M. caurina, M. zibellina, and Neovison vison) appear to have significant roles in the life history, persistence, and transmission of this nematode. Soboliphyme baturini readily switches among M. americana, M. caurina, Mustela erminea, or N. vison at any particular locality throughout its geographic range in North America, although Martes spp. could represent the source for nematodes in a broader array of mustelids. Molecular analyses (243 base pairs of mitochondrial gene nicotinamide dehydrogenase [ND4]) suggest that hypotheses for host specificity across an array of mustelid definitive hosts are not supported. The life cycle of S. baturini is explored through a review of diet literature for 2 marten species, M. americana and M. caurina, and other mustelids across the Holarctic. Shrews (Soricomorpha: Soricidae) comprise >8% of prey for these species of Martes, suggesting their putative role as paratenic hosts. Juvenile nematodes found in the diaphragms of soricids are genetically identical to adult S. baturini found in the stomachs of mustelids at the same locations in both Asia and North America, corroborating a role in transmission for species of Sorex. PMID:18163341

  5. The Insect Eaters.

    ERIC Educational Resources Information Center

    Naturescope, 1986

    1986-01-01

    Presents information about insectivores, including definitions and characteristics of shrews, moles, hedgehogs, and tenrecs. Contains descriptions of the teaching activities "Little Starnose" and "You and a Shrew." A reproducible worksheet is provided for use in "You and a Shrew." (TW)

  6. Taxonomic and systematic revisions to the North American Nimravidae (Mammalia, Carnivora)

    PubMed Central

    2016-01-01

    The Nimravidae is a family of extinct carnivores commonly referred to as “false saber-tooth cats.” Since their initial discovery, they have prompted difficulty in taxonomic assignments and number of valid species. Past revisions have only examined a handful of genera, while recent advances in cladistic and morphometric analyses have granted us additional avenues to answering questions regarding our understanding of valid nimravid taxa and their phylogenetic relationships. To resolve issues of specific validity, the phylogenetic species concept (PSC) was utilized to maintain consistency in diagnosing valid species, while simultaneously employing character and linear morphometric analyses for confirming the validity of taxa. Determined valid species and taxonomically informative characters were then employed in two differential cladistic analyses to create competing hypotheses of interspecific relationships. The results suggest the validity of twelve species and six monophyletic genera. The first in depth reviews of Pogonodon and Dinictis returned two valid species (P. platycopis, P. davisi) for the former, while only one for the latter (D. felina). The taxonomic validity of Nanosmilus is upheld. Two main clades with substantial support were returned for all cladistic analyses, the Hoplophoneini and Nimravini, with ambiguous positions relative to these main clades for the European taxa: Eofelis, Dinailurictis bonali, and Quercylurus major; and the North American taxa Dinictis and Pogonodon. Eusmilus is determined to represent a non-valid genus for North American taxa, suggesting non-validity for Old World nimravid species as well. Finally, Hoplophoneus mentalis is found to be a junior synonym of Hoplophoneus primaevus, while the validity of Hoplophoneus oharrai is reinstated. PMID:26893959

  7. Phenotypic Convergence in Genetically Distinct Lineages of a Rhinolophus Species Complex (Mammalia, Chiroptera)

    PubMed Central

    Jacobs, David S.; Babiker, Hassan; Bastian, Anna; Kearney, Teresa; van Eeden, Rowen; Bishop, Jacqueline M.

    2013-01-01

    Phenotypes of distantly related species may converge through adaptation to similar habitats and/or because they share biological constraints that limit the phenotypic variants produced. A common theme in bats is the sympatric occurrence of cryptic species that are convergent in morphology but divergent in echolocation frequency, suggesting that echolocation may facilitate niche partitioning, reducing competition. If so, allopatric populations freed from competition, could converge in both morphology and echolocation provided they occupy similar niches or share biological constraints. We investigated the evolutionary history of a widely distributed African horseshoe bat, Rhinolophus darlingi, in the context of phenotypic convergence. We used phylogenetic inference to identify and date lineage divergence together with phenotypic comparisons and ecological niche modelling to identify morphological and geographical correlates of those lineages. Our results indicate that R. darlingi is paraphyletic, the eastern and western parts of its distribution forming two distinct non-sister lineages that diverged ~9.7 Mya. We retain R. darlingi for the eastern lineage and argue that the western lineage, currently the sub-species R. d. damarensis, should be elevated to full species status. R. damarensis comprises two lineages that diverged ~5 Mya. Our findings concur with patterns of divergence of other co-distributed taxa which are associated with increased regional aridification between 7-5 Mya suggesting possible vicariant evolution. The morphology and echolocation calls of R. darlingi and R. damarensis are convergent despite occupying different biomes. This suggests that adaptation to similar habitats is not responsible for the convergence. Furthermore, R. darlingi forms part of a clade comprising species that are bigger and echolocate at lower frequencies than R. darlingi, suggesting that biological constraints are unlikely to have influenced the convergence. Instead, the striking similarity in morphology and sensory biology are probably the result of neutral evolutionary processes, resulting in the independent evolution of similar phenotypes. PMID:24312666

  8. Thermal energetics and torpor in the common pipistrelle bat, Pipistrellus pipistrellus (Vespertilionidae: Mammalia).

    PubMed

    Genoud, Michel; Christe, Philippe

    2011-10-01

    Rate of metabolism and body temperature were studied between -6C and 38C in the common pipistrelle bat Pipistrellus pipistrellus (Vespertilionidae), a European species lying close to the lower end of the mammalian size range (body mass 4.90.8g, N=28). Individuals maintained only occasionally a normothermic body temperature averaging 35.41.1C (N=4) and often showed torpor during metabolic runs. The thermoneutral zone was found above 33C, and basal rate of metabolism averaged 7.60.8mL O(2)h(-1) (N=28), which is 69% of the value predicted on the basis of body mass. Minimal wet thermal conductance was 161% of the expected value. During torpor, the rate of metabolism was related exponentially to body temperature with a Q(10) value of 2.57. Torpid bats showed intermittent ventilation, with the frequency of ventilatory cycles increasing exponentially with body temperature. Basal rate of metabolism (BMR) varied significantly with season and body temperature, but not with body mass. It was lower before the hibernation period than during the summer. The patterns observed are generally consistent with those exhibited by other vespertilionids of temperate regions. However, divergences occur with previous measurements on European pipistrelles, and the causes of the seasonal variation in BMR, which has only rarely been searched for among vespertilionids, remain to be examined. PMID:21736950

  9. Karyology of eight species of bats (Mammalia: Chiroptera) from Hainan Island, China.

    PubMed

    Wu, Yi; Motokawa, Masaharu; Li, Yu-Chun; Harada, Masashi; Chen, Zhong; Lin, Liang-Kong

    2009-01-01

    Karyotypes and chromosomal data are presented for eight bat species representing two families (Rhinolophidae and Vespertilionidae) from Hainan Island, China. The species investigated were Rhinolophus lepidus (2n = 62, FN = 60), R. pusillus (2n = 62, FN = 60), R. affinis (2n = 62, FN = 60), R. sinicus (2n = 36, FN = 60), Myotis horsfieldi (2n = 44, FN = 52), Pipistrellus abramus (2n = 26, FN = 44), Miniopterus australis (2n = 46, FN = 50) and M. schreibersii (2n = 46, FN = 50). The karyotype of Rhinolophus lepidus is reported for the first time. PMID:19847322

  10. A time-calibrated species-level phylogeny of bats (Chiroptera, Mammalia)

    PubMed Central

    Agnarsson, Ingi; Zambrana-Torrelio, Carlos M.; Flores-Saldana, Nadia Paola; May-Collado, Laura J.

    2011-01-01

    Despite their obvious utility, detailed species-level phylogenies are lacking for many groups, including several major mammalian lineages such as bats. Here we provide a cytochrome b genealogy of over 50% of bat species (648 terminal taxa). Based on prior analyzes of related mammal groups, cytb emerges as a particularly reliable phylogenetic marker, and given that our results are broadly congruent with prior knowledge, the phylogeny should be a useful tool for comparative analyzes. Nevertheless, we stress that a single-gene analysis of such a large and old group cannot be interpreted as more than a crude estimate of the bat species tree. Analysis of the full dataset supports the traditional division of bats into macro- and microchiroptera, but not the recently proposed division into Yinpterochiroptera and Yangochiroptera. However, our results only weakly reject the former and strongly support the latter group, and furthermore, a time calibrated analysis of a pruned dataset where most included taxa have the entire 1140bp cytb sequence finds monophyletic Yinpterochiroptera. Most bat families and many higher level groups are supported, however, relationships among families are in general weakly supported, as are many of the deeper nodes of the tree. The exceptions are in most cases apparently due to the misplacement of species with little available data, while in a few cases the results suggest putative problems with current classification, such as the non-monophyly of Mormoopidae. We provide this phylogenetic hypothesis, and an analysis of divergence times, as tools for evolutionary and ecological studies that will be useful until more inclusive studies using multiple loci become available. PMID:21327164

  11. Karyotype comparison and phylogenetic relationships of Pipistrellus-like bats (Vespertilionidae; Chiroptera; Mammalia).

    PubMed

    Volleth, M; Bronner, G; Gpfert, M C; Heller, K G; von Helversen; Yong, H S

    2001-01-01

    Detailed karyotype descriptions of 20 Pipistrellus-like bat species belonging to the family Vespertilionidae are presented. For the first time, chromosomal complements of four species, i.e. Pipistrellus stenopterus (2n = 32), P. javanicus (2n = 34), Hypsugo eisentrauti (2n = 42) and H. crassulus (2n = 30) are reported. A Pipistrellus kuhlii-like species from Madagascar represents a separate species distinguished from the European Pipistrellus kuhlii (2n = 44) by a diploid chromosome number of 42. Banded karyotypes are presented for the first time for Scotozous dormeri, Hypsugo capensis, Hesperoptenus blanfordi, Tylonycteris pachypus and robustula. Chromosomal evolution in the family Vespertilionidae is characterized by the conservation of entire chromosomal arms and reductions in diploid chromosome number via Robertsonian fusions. Less frequently, centric fissions, para- and pericentric inversions and centromere shifts were found to have occurred. In several cases a certain type of chromosomal change predominates in a karyotype. Examples of this are the acquisition of interstitial heterochromatic bands in Tylonycteris robustula, and centric shifts in P. javanicus, H. eisentrauti and Hesp. blanfordi. The species examined here belong to three tribes, i.e. Pipistrellini, Vespertilionini and Eptesicini, which are distinguished by chromosomal characteristics. According to our results, the species Pipistrellus (Neoromicia) capensis belongs to the Vespertilionini and not to the Pipistrellini. We therefore propose to elevate the subgenus Neoromicia to generic rank. PMID:11272789

  12. A reassessment of the taxonomic status of Paraglyptodon Castellanos, 1932 (Mammalia, Cingulata, Glyptodontia)

    NASA Astrophysics Data System (ADS)

    Cruz, Laura E.; Fernicola, Juan C.; Taglioretti, Matias; Toledo, Nestor

    2016-03-01

    Castellanos described and published about new genera of glyptodonts, according to a phylogenetic scheme mainly based on the evolution of the external surface of the dorsal carapace. Among these new genera, Castellanos proposed Paraglyptodon as the predecessor of Glyptodon, and included within Paraglyptodon all known species of Glyptodontinae recovered from "horizontes pre-Ensenadenses", and within Glyptodon all known species from "Horizontes pampeanos", restricting the latter to the Quaternary. All the species that belong to Paraglyptodon, that is Paraglyptodon chapalmalensis, Paraglyptodon uquiensis, Paraglyptodon dubius, and Paraglyptodon paranensis were established based on one, two or few osteoderms, mostly from the dorsal carapace. Regarding P. paranensis and P. dubius, Oliva and collaborators consider the first as a nomen vanum, representing an indeterminate Glyptodontinae, and the second as a synonym of P. chapalmalensis. Upon re-examination of the holotypes of P. chapalmalensis and P. uquiensis together with their comparison with other well-known specimens of glyptodonts, mainly with Glyptodon (of both juvenile and adult stages), we found the same ornamentation in different sections of the dorsal carapaces, particularly in P. chapalmalensis and in juvenile stages of Glyptodon spp. We could not identify features that would allow us to make a distinction between the holotype of P. uquiensis and Glyptodon spp. Therefore, we consider that a new taxon guide for naming the Upper Chapadmalalan biozone is necessary. The biostratigraphic range of Glyptodon could possibly be extended to the late Pliocene. However, new records and studies are needed to verify the existence of this taxon in the Chapadmalalan Stage/Age in its type locality.

  13. Comparative Morphology of Premolar Foramen in Lagomorphs (Mammalia: Glires) and Its Functional and Phylogenetic Implications

    PubMed Central

    Fostowicz-Frelik, ?ucja; Meng, Jin

    2013-01-01

    Lagomorphs (a group that consists of pikas, hares, rabbits and allies) are notable for their conservative morphology retained for most of their over 50 million years evolutionary history. On the other hand, their remarkable morphological uniformity partly stems from a considerable number of homoplasies in cranial and dental structures that hamper phylogenetic analyses. The premolar foramen, an opening in the palate of lagomorphs, has been characterized as an important synapomorphy of one clade, Ochotonidae (pikas). Within Lagomorpha, however, its phylogenetic distribution is much wider, the foramen being present not only in all ochotonids but also in leporids and stem taxa; its morphology and incidence also varies considerably across the order, even intraspecifically. In this study, we provide a broad survey of the taxonomic distribution of the premolar foramen in extant and fossil Lagomorpha and describe in detail the morphological variation of this character within the group. Micro-computed tomography was used to examine the hard palate and infraorbital groove morphology in Poelagus (Leporidae) and Ochotona. Scans revealed the course and contacts of the canal behind the premolar foramen and structural differences between the two crown clades. We propose that the premolar foramen has evolved independently in several lineages of Lagomorpha, and we discuss development and function of this foramen in the lagomorph skull. This study shows the importance of comprehensive studies on phylogenetically informative non-dental characters in Lagomorpha. PMID:24278178

  14. A tubulidentate suiform lineage (Tayassuidae, Mammalia) from the Early Miocene of Spain

    NASA Astrophysics Data System (ADS)

    Pickford, Martin; Morales, Jorge

    1998-08-01

    Small suiform artiodactyls from Moheda, Loranca and Corcolés, Spain, possess tubulidentate microstructure in their cheek tooth roots. The oldest specimens from Moheda (MN 2a) have a few scattered tubules near the apices of the molar roots, those from Loranca (MN 2b) have numerous tubules of various diameters in contact with each other, but oriented at various angles, while specimens from Corcolés (MN 4) are completely tubulidentate with well developed, sub-parallel tubules of sub-equal diameter running the entire length of the roots. The same series of fossils shows that with the passage of geological time the roots of this tayassuid lineage became more hypsorhizic and fusion of the roots increased, while the crowns of the teeth became simpler and thinner enamelled. Selection in this lineage was therefore focused upon increasing the longevity and wear resistance of the roots, while the role of the crowns of the teeth in mastication was de-emphasised. It is hypothesised that, as in Tubulidentata and Edentata, this suiform lineage was ingesting food items which contained significant quantities of adhérant earth. Whether the diet also contained ants and termites is not known.

  15. Evolution of nectarivory in phyllostomid bats (Phyllostomidae Gray, 1825, Chiroptera: Mammalia)

    PubMed Central

    2010-01-01

    Background Bats of the family Phyllostomidae show a unique diversity in feeding specializations. This taxon includes species that are highly specialized on insects, blood, small vertebrates, fruits or nectar, and pollen. Feeding specialization is accompanied by morphological, physiological and behavioural adaptations. Several attempts were made to resolve the phylogenetic relationships within this family in order to reconstruct the evolutionary transitions accompanied by nutritional specialization. Nevertheless, the evolution of nectarivory remained equivocal. Results Phylogenetic reconstructions, based on a concatenated nuclear-and mitochondrial data set, revealed a paraphyletic relationship of nectarivorous phyllostomid bats. Our phylogenetic reconstructions indicate that the nectarivorous genera Lonchophylla and Lionycteris are closer related to mainly frugivorous phyllostomids of the subfamilies Rhinophyllinae, Stenodermatinae, Carolliinae, and the insectivorous Glyphonycterinae rather than to nectarivorous bats of the Glossophaginae. This suggests an independent origin of morphological adaptations to a nectarivorous lifestyle within Lonchophyllinae and Glossophaginae. Molecular clock analysis revealed a relatively short time frame of about ten million years for the divergence of subfamilies. Conclusions Our study provides strong support for diphyly of nectarivorous phyllostomids. This is remarkable, since their morphological adaptations to nutrition, like elongated rostrums and tongues, reduced teeth and the ability to use hovering flight while ingestion, closely resemble each other. However, more precise examinations of their tongues (e.g. type and structure of papillae and muscular innervation) revealed levels of difference in line with an independent evolution of nectarivory in these bats. PMID:20525339

  16. Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae)

    PubMed Central

    Matte, Eunice M.; Castilho, Camila S.; Miotto, Renata A.; Sana, Denis A.; Johnson, Warren E.; OBrien, Stephen J.; de Freitas, Thales R. O.; Eizirik, Eduardo

    2013-01-01

    The puma is an iconic predator that ranges throughout the Americas, occupying diverse habitats. Previous phylogeographic analyses have revealed that it exhibits moderate levels of genetic structure across its range, with few of the classically recognized subspecies being supported as distinct demographic units. Moreover, most of the species molecular diversity was found to be in South America. To further investigate the phylogeographic structure and demographic history of pumas we analyzed mtDNA sequences from 186 individuals sampled throughout their range, with emphasis on South America. Our objectives were to refine the phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent. The estimated demographic history supports the interpretation that pumas suffered a severe demographic decline in the Late Pleistocene throughout their distribution, followed by population expansion and re-colonization of the range, initiating from South America. PMID:24385863

  17. A new middle eocene whale (Mammalia: Cetacea: Archaeoceti) and associated biota from Georgia

    USGS Publications Warehouse

    Hulbert, R.C., Jr.; Petkewich, R.M.; Bishop, G.A.; Bukry, D.; Aleshire, D.P.

    1998-01-01

    A shallow-marine fossil biota was recovered from the Blue Bluff unit (formerly part of the McBean Formation) in the Upper Coastal Plain of eastern Georgia. Biochronologically significant mollusks (e.g., Turritella nasuta, Cubitostrea sellaeformis, Pteropsella lapidosa) and calcareous nannoplankton (e.g., Chiasmolithus solitus, Reticulofenestra umbilica, Cribocentrum reticulatum) indicate a latest Lutetian-earliest Bartonian age, or about 40 to 41 Ma. Georgiacetus vogtlensis new genus and species is described from a well-preserved, partial skeleton. Georgiacetus is the oldest known whale with a true pterygoid sinus fossa in its basicranium and a pelvis that did not articulate directly with the sacral vertebrae, two features whose acquisitions were important steps toward adaptation to a fully marine existence. The posterior four cheek teeth of G. vogtlensis form a series of carnassial-like shearing blades. These teeth also bear small, blunt accessory cusps, which are regarded as being homologous with the larger, sharper accessory cusps of basilosaurid cheek teeth.

  18. Digital dissection of the masticatory muscles of the naked mole-rat, Heterocephalus glaber (Mammalia, Rodentia)

    PubMed Central

    Faulkes, Chris G.

    2014-01-01

    The naked mole-rat, Heterocephalus glaber, of the family Bathyergidae is a subterranean rodent that feeds on underground roots and tubers and digs extensive tunnel systems with its incisors. It is a highly unusual mammal with regard to its social structure, longevity, pain insensitivity and cancer resistance, all of which have made it the subject of a great deal of research in recent years. Yet, much of the basic anatomy of this species remains undocumented. In this paper, we describe the morphology of the jaw-closing musculature of the naked mole-rat, as revealed by contrast-enhanced micro-computed tomography. This technique uses an iodine stain to enable the imaging of soft tissues with microCT. The iodine-enhanced scans were used to create 3D reconstructions of the naked mole-rat masticatory muscles from which muscle masses were calculated. The jaw-closing musculature of Heterocephalus glaber is relatively very large compared to other rodents and is dominated by the superficial masseter, the deep masseter and the temporalis. The temporalis in particular is large for a rodent, covering the entirety of the braincase and much of the rear part of the orbit. The morphology of the masseter complex described here differs from two other published descriptions of bathyergid masticatory muscles, but is more similar to the arrangement seen in other rodent families. The zygomaticomandibularis (ZM) muscle does not protrude through the infraorbital foramen on to the rostrum and thus the naked mole-rat should be considered protrogomorphous rather than hystricomorphous, and the morphology is consistent with secondarily lost hystricomorphy as has been previously suggested for Bathyergidae. Overall, the morphology of the masticatory musculature indicates a species with a high bite force and a wide gape–both important adaptations for a life dominated by digging with the incisors. PMID:25024917

  19. Rodents and lagomorphs (Mammalia) from the Hemphillian (late Miocene) of Utah

    USGS Publications Warehouse

    Korth, W.W.; De Blieux, D. D.

    2010-01-01

    Four species of rodents (two heteromyids and two cricetids) and one lagomorph are identified from the late Tertiary Sevier River Formation of Utah. The heteromyids include a new genus and species of heteromyine, Metaliomys sevierensis, which is intermediate in morphology between the Clarendonian and early Hemphillian Diprionomys Kellogg and the extant genera Liomys and Heteromys. A single specimen is referred to Diprionomys sp., cf. D. minimus (Kellogg). The cricetid Paronychomys lemredfieldi Jacobs is known from the Hemphillian of Arizona. The second cricetid is referred to a new genus Basirepomys. Peromyscus pliocenicus Wilson from the Hemphillian of California is designated as the type species of the new genus, to which the new species B. robertsi from Utah is referred. Basirepomys is viewed as intermediate between Peromyscus and the basal neotomyine Repomys May from the late Hemphillian and Blancan. The only lagomorph in the fauna is Hypolagus vetus (Kellogg). Four of the taxa recognized from the Sevier River Formation (Diprionomys, Paronychomys lemredfieldi, Basirepomys, and Hypolagus vetus) are elsewhere known from the Hemphillian of North America. However, it is not possible at this time to determine whether the fauna is early or late Hemphillian. ?? 2010 by the Society of Vertebrate Paleontology.

  20. A new Mammutidae (Proboscidea, Mammalia) from the Late Miocene of Gansu Province, China.

    PubMed

    Mothé, Dimila; Avilla, Leonardo S; Zhao, Desi; Xie, Guangpu; Sun, Boyang

    2016-03-01

    The "Yanghecun specimen", a proboscidean specimen represented by a mandible from Miocene of China and previously described as Gomphotheriidae, is here reviewed and described as a new genus and species of Mammutidae: Sinomammut tobieni. This taxon is a longirostrine mastodon, lacking lower tusks, and bearing a wide last molar with oblique and non-inflated lophids, broad transverse interlophids, and yoke-like wear figures. Phylogenetic analysis of Mammutidae based on dental and mandibular features recovered S. tobieni as sister group of the mastodon Mammut. The longirostrine condition and the well-developed lower incisors seem to be primitive for Mammutidae, while the brevirostry is the derived condition, probably emerged during the middle Miocene (12-11 Mya). However, two derived conditions are recognized to the lower tusks: the absence of lower tusks (S. tobieni) and the occasional presence of vestigial lower tusks (Mammut). PMID:26839998

  1. Pakicetus inachus and the origin of whales and dolphins (Mammalia: Cetacea).

    PubMed

    Oelschlger, H A

    1987-01-01

    The present paper is concerned with the comparative morphology of the archeocete and odontocete skull. Among the archeocetes, the recently described lower Eocene Pakicetus inachus obviously represents an early stage of adaptation to aquatic life. The morphology of the incomplete cranial remains, however, gives no evidence that Pakicetus was an amphibious intermediate stage. The evolution of advanced archeocetes and odontocetes is characterized by the successive acquirement of new morphological devices related to the emission and perception of ultrasound under water. The formation of a sonar system in odontocetes obviously not only helped to compensate for the loss of the peripheral olfactory system but moreover was a substantial factor in the evolution of the exceptional dolphin brain. PMID:3692104

  2. Osteoderm morphology and development in the nine-banded armadillo, Dasypus novemcinctus (Mammalia, Xenarthra, Cingulata).

    PubMed

    Vickaryous, Matthew K; Hall, Brian K

    2006-11-01

    Among modern mammals, armadillos (Xenarthra, Cingulata) are the only group that possesses osteoderms, bony inclusions within the integument. Along the body, osteoderms are organized into five discrete assemblages: the head, pectoral, banded, pelvic, and tail shields. The pectoral, banded, and pelvic shields articulate to form the carapace. We examined osteoderm skeletogenesis in the armadillo Dasypus novemcinctus using serial and whole-mount histochemistry. Compared with the rest of the skeleton, osteoderms have a delayed onset of development. Skeletogenesis begins as condensations of osteoblasts secreting osteoid, localized within the papillary layer of the dermis. Osteoderm formation is asynchronous both within each shield and across the body. The first osteoderms to mineralize are situated within the pectoral shield of the carapace, followed by elements within the banded, head, pelvic, and tail shields. In general, within each shield ossification begins craniomedially and proceeds caudally and laterally, except over the head, where the earliest elements form over the frontal and parietal bones. The absence of cartilage precursors indicates that osteoderms are dermal elements, possibly related to the all-encompassing vertebrate dermal skeleton (exoskeleton). The mode of development of D. novemcinctus osteoderms is unlike that described for squamate osteoderms, which arise via bone metaplasia, and instead is comparable with intramembranously derived elements of the skull. PMID:17051548

  3. Frugivory by phyllostomid bats (Mammalia: Chiroptera) in a restored area in Southeast Brazil

    NASA Astrophysics Data System (ADS)

    Silveira, Maurcio; Trevelin, Leonardo; Port-Carvalho, Marcio; Godoi, Simone; Mandetta, Elizabeth Neuenhaus; Cruz-Neto, Ariovaldo P.

    2011-01-01

    We studied the potential contribution of frugivorous bats to the reestablishment of vegetational diversity in a restored area. We analysed the diets of the bat species and the differences between them in the consumption of fruits of autochtonous and allochthonous species. Planted (autochtonous) species were the basis of diets, especially Solanum mauritianum and Cecropia pachystachya, whereas for allochthonous species we found that Piperaceae to be of particular importance. Carollia perspicillata was the main seed disperser for allochthonous species, and potentially the most important bat in the promotion of vegetation diversity in the study area. Our results suggest that frugivorous bats are especially important in the reestablishment of vegetation in disturbed areas, and that restorarion efforts should focus on the planting of different zoochorous species that would guarantee a high year-round fruit production, thereby facilitating natural plant reestablishment by frugivorous bats in regenerating areas.

  4. Phylogeny and divergence of the pinnipeds (Carnivora: Mammalia) assessed using a multigene dataset

    PubMed Central

    Higdon, Jeff W; Bininda-Emonds, Olaf RP; Beck, Robin MD; Ferguson, Steven H

    2007-01-01

    Background Phylogenetic comparative methods are often improved by complete phylogenies with meaningful branch lengths (e.g., divergence dates). This study presents a dated molecular supertree for all 34 world pinniped species derived from a weighted matrix representation with parsimony (MRP) supertree analysis of 50 gene trees, each determined under a maximum likelihood (ML) framework. Divergence times were determined by mapping the same sequence data (plus two additional genes) on to the supertree topology and calibrating the ML branch lengths against a range of fossil calibrations. We assessed the sensitivity of our supertree topology in two ways: 1) a second supertree with all mtDNA genes combined into a single source tree, and 2) likelihood-based supermatrix analyses. Divergence dates were also calculated using a Bayesian relaxed molecular clock with rate autocorrelation to test the sensitivity of our supertree results further. Results The resulting phylogenies all agreed broadly with recent molecular studies, in particular supporting the monophyly of Phocidae, Otariidae, and the two phocid subfamilies, as well as an Odobenidae + Otariidae sister relationship; areas of disagreement were limited to four more poorly supported regions. Neither the supertree nor supermatrix analyses supported the monophyly of the two traditional otariid subfamilies, supporting suggestions for the need for taxonomic revision in this group. Phocid relationships were similar to other recent studies and deeper branches were generally well-resolved. Halichoerus grypus was nested within a paraphyletic Pusa, although relationships within Phocina tend to be poorly supported. Divergence date estimates for the supertree were in good agreement with other studies and the available fossil record; however, the Bayesian relaxed molecular clock divergence date estimates were significantly older. Conclusion Our results join other recent studies and highlight the need for a re-evaluation of pinniped taxonomy, especially as regards the subfamilial classification of otariids and the generic nomenclature of Phocina. Even with the recent publication of new sequence data, the available genetic sequence information for several species, particularly those in Arctocephalus, remains very limited, especially for nuclear markers. However, resolution of parts of the tree will probably remain difficult, even with additional data, due to apparent rapid radiations. Our study addresses the lack of a recent pinniped phylogeny that includes all species and robust divergence dates for all nodes, and will therefore prove indispensable to comparative and macroevolutionary studies of this group of carnivores. PMID:17996107

  5. Ptolemaiida, a new order of Mammalia--with description of the cranium of Ptolemaia grangeri.

    PubMed Central

    Simons, E L; Bown, T M

    1995-01-01

    All records of the exotic mammalian family Ptolemaiidae are known from 182 m of section in the lower to middle parts of the upper Eocene and lower Oligocene Jebel Qatrani Formation, Fayum Depression, Egypt. Previous tentative assignments of ptolemaiid affinity have suggested that these animals are allied with the primitive suborder Pantolesta (currently placed in the order Cimolesta). Though perhaps ultimately derived from an unknown member of that group, the likelihood that ptolemaiids constitute a distinct group is considered, and analysis of all known materials of Ptolemaia, Qarunavus, and Cleopatrodon demonstrates that these genera belong in their own order, the Ptolemaiida, described here. The morphologically unique dentition and only known ptolemaiid cranium, that of Ptolemaia grangeri, is described. Although Qarunavus and Cleopatrodon show some similarities in primitive characters to European merialine Paroxyclaenidae (suborder Pantolesta), their affinities clearly lie with Ptolemaia and the Ptolemaiida. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:11607526

  6. New Mesotheriidae (Mammalia, Notoungulata, Typotheria), geochronology and tectonics of the Caragua area, northernmost Chile

    NASA Astrophysics Data System (ADS)

    Flynn, John J.; Croft, Darin A.; Charrier, Reynaldo; Wyss, Andr R.; Hrail, Grard; Garca, Marcelo

    2005-05-01

    Few mammal fossils were known from the Altiplano or adjoining parts of northern Chile until recently. We report a partial mesotheriid palate from the vicinity of Caragua (Huaylas Formation) in northernmost Chile. The new material helps resolve contradictory taxonomic assignments (and age implications) of the two mesotheriid specimens previously reported from the area. Herein we refer all three mesotheriid specimens to a new taxon, Caraguatypotherium munozi, which is closely related to Plesiotypotherium, Typotheriopsis, Pseudotypotherium, and Mesotherium. This phylogenetic placement permits a revised biochronologic estimate of a post-Friasian/pre-Huayquerian (15-9 Ma) age for the Huaylas Formation, consistent with new radioisotopic dates from the upper Huaylas Formation and its bracketing stratigraphic units. Improved geochronologic control for the Huaylas Formation has important implications for the timing of tectonic events in the Precordillera/Altiplano of northern Chile. Structural, stratigraphic, and temporal data suggest the onset of rapid, progressive deformation shortly after the deposition of the older Zapahuira Formation, continuing at least partly through deposition of the Huaylas Formation. Deposition of the Huaylas Formation was short lived (between 10-12 Ma), possibly stemming from activity on the Copaquilla-Tignmar Fault in the eastern Precordillera. This deformation is associated with the development of the Oxaya Anticline and activity of the Ausipar Fault west of the study region on the frontal limb of the anticline in the westernmost Precordillera. Faulting and folding occurred rapidly, beginning at 11.4 Ma (shortly after deposition of the youngest extrusives of the Zapahuira Formation) and before 10.7 Ma (the age of the gently dipping horizons within the upper Huaylas Formation that overlie the mammal fossils and an intraformational unconformity). Mesotheriids are the only Tertiary fossil mammals known from the Precordillera of northernmost Chile thus far; the group is common and diverse in faunas from the Altiplano of Bolivia (and a fauna recently recovered from the Chilean Altiplano), in contrast to most higher-latitude and tropical assemblages. This distinctiveness indicates that intermediate latitudes may have been biogeographically distinct and served as a center of diversification for mesotheriids and other groups of indigenous South American mammals.

  7. Mandible shape and dwarfism in squirrels (Mammalia, Rodentia): interaction of allometry and adaptation

    NASA Astrophysics Data System (ADS)

    Hautier, Lionel; Fabre, Pierre-Henri; Michaux, Jacques

    2009-06-01

    Squirrels include several independent lineages of dwarf forms distributed into two ecological groups: the dwarf tree and flying squirrels. The mandible of dwarf tree squirrels share a highly reduced coronoid process and a condylar process drawn backwards. Dwarf flying squirrels on the other hand, have an elongated coronoid process and a well-differentiated condylar process. To interpret such a difference, Elliptic Fourier Transform was used to evaluate how mandible shape varies with dwarfism in sciurids. The results obtained show that this clear-cut difference cannot be explained by a simple allometric relationship in relation with size decrease. We concluded that the retention of anteriorly positioned eye sockets, in relation with distance estimation, allowed the conservation of a well-differentiated coronoid process in all flying species, despite the trend towards its reduction observed among sciurids as their size decreases.

  8. First Castorid (Mammalia, Rodentia) from the Middle Miocene of Southeast Asia

    NASA Astrophysics Data System (ADS)

    Suraprasit, Kantapon; Chaimanee, Yaowalak; Martin, Thomas; Jaeger, Jean-Jacques

    2011-04-01

    Today and in the Tertiary, the geographical distribution of castorids is limited throughout all of the northern continents. Fossils of the Castoridae genus Steneofiber are abundant in many localities of Eurasia from the late Oligocene to Pliocene period. Recently, Steneofiber fossils were discovered in two localities of northern Thailand, Mae Moh and Chiang Muan coal mines, in layers of late middle Miocene age. These discoveries represent the first records of castorids from Southeast Asia and correspond to their southernmost known range. The focus of this study is to describe this new Thai species of Steneofiber and to define its wear stages from the molar occlusal surfaces by using micro-CT scan analysis. The CT scan technique permits the analysis of the virtual occlusal surface changes from wear, allowing easier comparison to related species of Steneofiber cheek teeth without destroying the teeth. The new species, Steneofiber siamensis n. sp., can be distinguished from the other species of Steneofiber by several distinct characters, longer mesostriid on p4, presence of premesostria and metastria on P4, which are smaller than most of the other known species. The occurrence of this new castorid also supports a subtropical to tropical paleoclimate for these two localities of northern Thailand.

  9. MAMMALIA CELL CYTOTOXICITY AND GENOTOXICITY ANALYSIS OF DRINKING WATER DISINFECTION BYPRODUCTS. (R825956)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  10. A structural intermediate between triisodontids and mesonychians (Mammalia, Acreodi) from the earliest Eocene of Portugal

    NASA Astrophysics Data System (ADS)

    Tabuce, Rodolphe; Clavel, Julien; Antunes, Miguel Telles

    2011-02-01

    A new mammal, Mondegodon eutrigonus gen. et sp. nov., is described from the earliest Eocene locality of Silveirinha, Portugal. This species shows dental adaptations indicative of a carnivorous diet. M. eutrigonus is referred to the order Acreodi and considered, along with the early Paleocene North American species Oxyclaenus cuspidatus, as a morphological intermediate between two groups of ungulate-like mammals, namely, the triisodontids and mesonychians. Considering that triisodontids are early to early-late Paleocene North American taxa, Mondegodon probably belongs to a group that migrated from North America towards Europe during the first part of the Paleocene. Mondegodon could represent thus a relict genus, belonging to the ante-Eocene European mammalian fauna. The occurrence of such a taxon in Southern Europe may reflect a period of isolation of this continental area during the Paleocene/Eocene transition. In this context, the non-occurrence of closely allied forms of Mondegodon in the Eocene North European mammalian faunas is significant. This strengthens the hypothesis that the mammalian fauna from Southern Europe is characterized by a certain degree of endemism during the earliest Eocene. Mondegodon also presents some striking similarities with an unnamed genus from the early Eocene of India which could represent the first Asian known transitional form between the triisodontids and mesonychians.

  11. Systematical and biochronological review of Plio-Pleistocene Alceini (Cervidae; Mammalia) from Eurasia

    NASA Astrophysics Data System (ADS)

    Breda, Marzia; Marchetti, Marco

    2005-03-01

    Systematics, taxonomy and phylogeny of Eurasian fossil moose are discussed in order to analyse their distribution in space and time. The largest European collections were studied. We recognise the genus Cervalces, including the chronospecies C. gallicus, C. carnutorum and C. latifrons, as well as the genus Alces, with the species A. alces. Cervalces differs from Alces in the facial area, in the length of the antlers and in the orientation of the palmation. Taking into account as more bibliography as possible, we suggest that the Siberian remains, due to their distance from the type localities, have size ranges and beam proportions a little different from the coeval European ones, so they are regarded as different geographic populations. Cervalces latifrons postremus systematics and chronology have been reconsidered. It results that it was present only in Siberia during the penultimate glaciation and was of the same body size as typical C. latifrons. It is likely that A. alces is not the direct descendant of the last European Cervalces, but its origin is still an open question. The present analysis provides a clearer picture of the geographical and chronological distribution of Cervalces and Alces.

  12. The taxonomic status of the Yucatan brown brocket, Mazama pandora (Mammalia: Cervidae)

    USGS Publications Warehouse

    Medellin, R.A.; Gardner, A.L.; Aranda, J.M.

    1998-01-01

    The Yucatan brown brocket deer, described as Mazama pandora, is now treated as a subspecies of either the common brown brocket, Mazama gouazoubira, or of the red brocket, M. americana. Analysis of brocket deer from Mexico and Central and South America, reveals that the Yucatan brown brocket is sympatric with the red brocket in Mexico and, while similar to M. gouazoubira, warrents recognition as a separate species.

  13. Red pandas (Mammalia, Carnivora: Parailurus) in the biomes of North Eurasia and North America

    NASA Astrophysics Data System (ADS)

    Matishov, G. G.; Kalmykov, N. P.

    2011-05-01

    The discovery of the Pliocene red panda ( Parailurus) in the West Transbaikal area, as well as Asian raccoons in North Eurasia and North America, indicates that forested areas with bamboo bushes were wide-spread in the Holarctic during the Neogene. During the Late Pliocene, due to a gradual cooling of the climate, altiplanation, and other factors, their habitat started disintegrating, and red pandas began dying out, surviving only in China.

  14. A new Early Oligocene peradectine marsupial (Mammalia)from the Burqin region of Xinjiang, China

    NASA Astrophysics Data System (ADS)

    Ni, Xijun; Meng, Jin; Wu, Wenyu; Ye, Jie

    2007-03-01

    Tertiary marsupial records are very scarce in Asia. A new peradectine marsupial, Junggaroperadectes burqinensis gen. et sp. nov., is reported from the Early Oligocene Keziletuogayi Formation in the Burqin region, Xinjiang, China. This new species is based on a single right upper M2. The tooth possesses a straight centrocrista, a characteristic of peradectines. Its main cusps lean buccally, with the paracone being smaller and lower than the metacone. The conules and stylar cusps are weakly developed. These characters distinguish J. burqinensis from Euro-American Tertiary peradectines, but they also imply a close phylogenetic relationship to Siamoperadectes and Sinoperadectes, two Asian Early Miocene peradectines.

  15. Specific chromosomal defects associated with ultraviolet radiation-induced cutaneous tumors in Monodelphis domestica (Marsupialia, mammalia).

    PubMed

    Pathak, S; Gadhia, M; Dhaliwal, M K; Applegate, L A; Ley, R D

    1992-12-01

    Cytogenetic analysis of eight ultraviolet radiation (UVR)-induced cutaneous tumors and one spontaneously transformed fibroblast cell line of Monodelphis domestica showed that two of the tumor cell lines were of murine origin and that the remaining six marsupial tumor cell lines had hyperdiploid stemline numbers ranging from 21 to 31. Each tumor cell line showed structural and numerical abnormalities. The single transformed fibroblast cell line also showed a hyperdiploid chromosome number with structural and numerical defects. All M. domestica tumor cell lines and the fibroblast line showed a common structural abnormality: deletion of the short arm (p) of a chromosome 1. In some cell lines, the short arm of chromosome 1 was replaced by a translocation with the X chromosome. We suggest, based on the Giemsa-banding homology of chromosome 1p in M. domestica and human chromosome 6q involved in melanomas, that marsupial chromosome 1p may harbor tumor suppressor gene(s) that are associated with UVR-induced cutaneous tumors. PMID:1486565

  16. Phylogeny of the Carnivora (Mammalia): congruence vs incompatibility among multiple data sets.

    PubMed

    Flynn, J J; Nedbal, M A

    1998-06-01

    The purpose of this study was to determine the higher-level phylogenetic relationships among Carnivora, using a conditional data combination (CDC) approach to analyzing multiple data sets. New nucleotide sequences (851 base pairs from intron I of the transthyretin gene) among 22 representatives of the 11 families of Carnivora were generated and analyzed in concert with, and comparison to, other mitochondrial and morphological character data. Conditional data combination analyses of the four independent data sets (transthyretin intron I, cytochrome b, partial 12S rRNA, and morphology) indicate that the phylogenetic results derived from each generally agree, with two exceptions. The first exception, signal heterogeneity in comparisons involving transthyretin and morphology, provides an example where phylogenetic conclusions drawn from total evidence analyses may differ from conclusions drawn from CDC analyses. The second exception demonstrates that while a CDC method may reject the null hypothesis of homogeneity for a particular partition, including that partition in combined analyses, may nevertheless provide an overall increase in phylogenetic signal, in terms of nodal support for most associations, without altering the topology derived from the combined homogeneous data partitions. Phylogenetic reconstruction among the feliform families supports a sister-group relationship between the hyaenas (Hyaenidae) and mongooses (Herpestidae) and places the African palm civet (Nandinia) as basal to all other living Feliformia. Among the caniform families, CDC analyses strongly support the previously enigmatic red panda (Ailurus) as a monotypic lineage that is sister to Musteloidea sensu stricto (mustelids plus procyonids), in addition to pinniped monophyly and a sister-group relationship between the walrus and sea lions. PMID:9667990

  17. Molecular phylogeny of the carnivora (mammalia): assessing the impact of increased sampling on resolving enigmatic relationships.

    PubMed

    Flynn, John J; Finarelli, John A; Zehr, Sarah; Hsu, Johnny; Nedbal, Michael A

    2005-04-01

    This study analyzed 76 species of Carnivora using a concatenated sequence of 6243 bp from six genes (nuclear TR-i-I, TBG, and IRBP; mitochondrial ND2, CYTB, and 12S rRNA), representing the most comprehensive sampling yet undertaken for reconstructing the phylogeny of this clade. Maximum parsimony and Bayesian methods were remarkably congruent in topologies observed and in nodal support measures. We recovered all of the higher level carnivoran clades that had been robustly supported in previous analyses (by analyses of morphological and molecular data), including the monophyly of Caniformia, Feliformia, Arctoidea, Pinnipedia, Musteloidea, Procyonidae + Mustelidae sensu stricto, and a clade of (Hyaenidae + (Herpestidae + Malagasy carnivorans)). All of the traditional "families," with the exception of Viverridae and Mustelidae, were robustly supported as monophyletic groups. We further have determined the relative positions of the major lineages within the Caniformia, which previous studies could not resolve, including the first robust support for the phylogenetic position of marine carnivorans (Pinnipedia) within the Arctoidea (as the sister-group to musteloids [sensu lato], with ursids as their sister group). Within the pinnipeds, Odobenidae (walrus) was more closely allied with otariids (sea lions/fur seals) than with phocids ("true" seals). In addition, we recovered a monophyletic clade of skunks and stink badgers (Mephitidae) and resolved the topology of musteloid interrelationships as: Ailurus (Mephitidae (Procyonidae, Mustelidae [sensu stricto])). This pattern of interrelationships of living caniforms suggests a novel inference that large body size may have been the primitive condition for Arctoidea, with secondary size reduction evolving later in some musteloids. Within Mustelidae, Bayesian analyses are unambiguous in supporting otter monophyly (Lutrinae), and in both MP and Bayesian analyses Martes is paraphyletic with respect to Gulo and Eira, as has been observed in some previous molecular studies. Within Feliformia, we have confirmed that Nandinia is the outgroup to all other extant feliforms, and that the Malagasy Carnivora are a monophyletic clade closely allied with the mongooses (Herpestidae [sensu stricto]). Although the monophyly of each of the three major feliform clades (Viverridae sensu stricto, Felidae, and the clade of Hyaenidae + (Herpestidae + Malagasy carnivorans)) is robust in all of our analyses, the relative phylogenetic positions of these three lineages is not resolvable at present. Our analyses document the monophyly of the "social mongooses," strengthening evidence for a single origin of eusociality within the Herpestidae. For a single caniform node, the position of pinnipeds relative to Ursidae and Musteloidea, parsimony analyses of data for the entire Carnivora did not replicate the robust support observed for both parsimony and Bayesian analyses of the caniform ingroup alone. More detailed analyses and these results demonstrate that outgroup choice can have a considerable effect on the strength of support for a particular topology. Therefore, the use of exemplar taxa as proxies for entire clades with diverse evolutionary histories should be approached with caution. The Bayesian analysis likelihood functions generally were better able to reconstruct phylogenetic relationships (increased resolution and more robust support for various nodes) than parsimony analyses when incompletely sampled taxa were included. Bayesian analyses were not immune, however, to the effects of missing data; lower resolution and support in those analyses likely arise from non-overlap of gene sequence data among less well-sampled taxa. These issues are a concern for similar studies, in which different gene sequences are concatenated in an effort to increase resolving power. PMID:16012099

  18. [Geographic variation of the fox Lycalopex culpaeus (Mammalia, Canidae) in Chile: taxonomic implications].

    PubMed

    Guzmn, Jonathan A; D'Ela, Guillermo; Ortiz, Juan Carlos

    2009-01-01

    We studied the geographic variation of skulls of Lycalopex culpaeus using qualitative and quantative analyses. The sampling area covered Chile, from its northern portion, to Tierra del Fuego and the neighbouring Hoste Island, as well as part of Argentina. Five subespecies are currently recognized from this large area. We found two morphotypes that are segregated geographically. Both groups mostly differ by morphometric attributes, followed by qualitative features. Specimens from northern Chile (Tarapac and Antofagasta) have small skulls, short rostrum, a liriform sagital zone, and lack the interparietal crest. The second group is formed by specimens from north-western and central Argentina, central-south Chile, Patagonia, and the austral islands of Tierra del Fuego and Hoste. This group presents a strong sagital crest, large rostrum, and a large skull. Our results agree with observed patterns of mitochondrial DNA variation. We propose to retain the name L. c. andinus for the populations of northern Chile and to synonymize L. c. magellanicus, L. c. lycoides, and L. c. smithersi under L. c. culpaeus. PMID:19637719

  19. Pliocene Carnivora (Mammalia) from the Hadar Formation at Dikika, Lower Awash Valley, Ethiopia

    NASA Astrophysics Data System (ADS)

    Geraads, Denis; Alemseged, Zeresenay; Bobe, René; Reed, Denné

    2015-07-01

    We report here on further study of the Carnivora collected by the Dikika Research Project at Dikika, in the Hadar Formation south of the type locality since 2000. The Canidae and the otter Enhydriodon have been described elsewhere, so we focus here on the other Mustelidae and on the Felidae and Hyaenidae. All Hyaenidae are referred to Crocuta, but differences in size and tooth proportions suggest two species that might belong to distinct lineages. An associated set of upper and lower teeth is made the type of a new species of Lutra that must be close to the divergence of Lutra palaeindica, Lutra lutra, and Hydrictis maculicollis. Sample size is still small, but the Dikika assemblage differs from others of similar age in the abundance of hyenas relative to felids.

  20. Dental microwear patterns of extant and extinct Muridae (Rodentia, Mammalia): ecological implications

    NASA Astrophysics Data System (ADS)

    Gomes Rodrigues, Helder; Merceron, Gildas; Viriot, Laurent

    2009-04-01

    Extant species of Muridae occupy a wide array of habitats and have diverse dietary habits. Consequently, their dental microwear patterns represent a potential clue to better understand the paleoecology of their extinct relatives, which are abundant in many Old World Neogene localities. In this study, dental microwear is investigated for specimens of 17 extant species of murine and deomyine rodents in order to test the reliability of this method and infer dietary preferences on the fossil species Sadomys afarensis. This extinct form comes from a mid-Pliocene site (AL 327) located at the Hadar Formation (Ethiopia) known to have delivered many hominid specimens of Australopithecus afarensis. A significant correlation between microwear patterns and diet is detected. Thus, grass, fruit, and insect eaters display, respectively, high amounts of fine scratches, wide scratches, and large pits. Moreover, some aspects of the paleoecology of S. afarensis, including feeding habits, could be assessed in regard to its dental microwear pattern. Indeed, it probably had feeding habits similar to that of living grass eaters. These results concur with the presence of open to woodland areas covered by an herbaceous vegetal layer, including monocotyledons, in the vicinity of this mid-Pliocene locality.

  1. Sexual dimorphism of the internal mandibular chamber in Fayum Pliohyracidae (Mammalia)

    USGS Publications Warehouse

    de Blieux, D.D.; Baumrind, M.R.; Simons, E.L.; Chatrath, P.S.; Meyer, G.E.; Attia, Y.S.

    2006-01-01

    An internal mandibular fenestra and chamber are found in many fossil hyracoids. The internal mandibular fenestra is located on the lingual surface of the mandibular corpus and opens into a chamber within the mandible. The mandibular chamber is maximally developed in late Eocene Thyrohyrax meyeri and early Oligocene Thyrohyrax domorictus from the Fayum Province of Egypt. The function of this chamber is unknown as it is not found in extant hyraxes, nor is it known to occur in any other mammal. In Thyrohyrax, this feature appears to be sexually dimorphic because it is confined to roughly one half of the specimens that otherwise cannot be separated by dental characteristics or measurements. It has been suggested that the chamber is found in females based on the presumed distribution of this character in other fossil hyracoids. Fossils from Fayum Quarry L-41, preserving the sexually dimorphic anterior dentition, show that, in Thyrohyrax meyeri and Thyrohyrax domorictus, the internal mandibular chamber is found in males. In Thyrohyrax litholagus, an internal mandibular fenestra and inflated mandibular chamber occurs in males whereas females show the variable presence of an internal mandibular fossa or fenestra but lack an expanded chamber. Other genera show differing patterns of sexual variation in which some Fayum hyracoids have an internal mandibular fenestra in both sexes but with the greatest development of the mandibular chamber occurring in males. We review functions proposed for the internal mandibular chamber and suggest that it housed a laryngeal air sac that may have had a vocal function by acting as a resonating chamber. ?? 2006 by the Society of Vertebrate Paleontology.

  2. Phenotypic convergence in genetically distinct lineages of a Rhinolophus species complex (Mammalia, Chiroptera).

    PubMed

    Jacobs, David S; Babiker, Hassan; Bastian, Anna; Kearney, Teresa; van Eeden, Rowen; Bishop, Jacqueline M

    2013-01-01

    Phenotypes of distantly related species may converge through adaptation to similar habitats and/or because they share biological constraints that limit the phenotypic variants produced. A common theme in bats is the sympatric occurrence of cryptic species that are convergent in morphology but divergent in echolocation frequency, suggesting that echolocation may facilitate niche partitioning, reducing competition. If so, allopatric populations freed from competition, could converge in both morphology and echolocation provided they occupy similar niches or share biological constraints. We investigated the evolutionary history of a widely distributed African horseshoe bat, Rhinolophus darlingi, in the context of phenotypic convergence. We used phylogenetic inference to identify and date lineage divergence together with phenotypic comparisons and ecological niche modelling to identify morphological and geographical correlates of those lineages. Our results indicate that R. darlingi is paraphyletic, the eastern and western parts of its distribution forming two distinct non-sister lineages that diverged ~9.7 Mya. We retain R. darlingi for the eastern lineage and argue that the western lineage, currently the sub-species R. d. damarensis, should be elevated to full species status. R. damarensis comprises two lineages that diverged ~5 Mya. Our findings concur with patterns of divergence of other co-distributed taxa which are associated with increased regional aridification between 7-5 Mya suggesting possible vicariant evolution. The morphology and echolocation calls of R. darlingi and R. damarensis are convergent despite occupying different biomes. This suggests that adaptation to similar habitats is not responsible for the convergence. Furthermore, R. darlingi forms part of a clade comprising species that are bigger and echolocate at lower frequencies than R. darlingi, suggesting that biological constraints are unlikely to have influenced the convergence. Instead, the striking similarity in morphology and sensory biology are probably the result of neutral evolutionary processes, resulting in the independent evolution of similar phenotypes. PMID:24312666

  3. Systematics and Evolution of the Miocene Three-Horned Palaeomerycid Ruminants (Mammalia, Cetartiodactyla)

    PubMed Central

    Sánchez, Israel M.; Cantalapiedra, Juan L.; Ríos, María; Quiralte, Victoria; Morales, Jorge

    2015-01-01

    Palaeomerycids were strange three-horned Eurasian Miocene ruminants known through fossils from Spain to China. We here study their systematics, offering the first cladistic phylogeny of the best-known species of the group, and also reassess their phylogenetic position among ruminants, which is currently disputed. The beautifully preserved remains of a new palaeomerycid from middle Miocene deposits of Spain, Xenokeryx amidalae gen. et sp. nov., helps us to better understand palaeomerycid anatomy, especially that of the nuchal region in the skull, significantly improving our current knowledge on these enigmatic ruminants. Our results show two main lineages of palaeomerycids, one containing the genus Ampelomeryx diagnosed by a characteristic type of cranium / cranial appendages and some dental derived traits, and another one that clusters those forms more closely related to Triceromeryx than to Ampelomeryx, characterized by a more derived dentition and a set of apomorphic cranial features. Xenokeryx branches as a basal offshoot of this clade. Also, we find that Eurasian palaeomerycids are not closely related to North American dromomerycids, thus rejecting the currently more accepted view of palaeomerycids as the Eurasian part of the dromomerycid lineage. Instead of this, palaeomerycids are nested with the African Miocene pecoran Propalaeoryx and with giraffoids. On the other hand, dromomerycids are closely related to cervids. We define a clade Giraffomorpha that includes palaeomerycids and giraffids, and propose an emended diagnosis of the Palaeomerycidae based on cranial and postcranial characters, including several features of the cranium not described so far. We also define the Palaeomerycidae as the least inclusive clade of pecorans containing Triceromeryx and Ampelomeryx. Finally, we reassess the taxonomy of several palaeomerycid taxa. PMID:26630174

  4. First isolation and genotyping of Toxoplasma gondii from bats (Mammalia: Chiroptera).

    PubMed

    Cabral, A D; Gama, A R; Sodré, M M; Savani, E S M M; Galvão-Dias, M A; Jordão, L R; Maeda, M M; Yai, L E O; Gennari, S M; Pena, H F J

    2013-03-31

    There are currently no reports on the isolation and molecular examination of Toxoplasma gondii from bats. Here, we report the isolation and genotypic characterisation of two T. gondii isolates from bats. A total of 369 bats from different municipalities in São Paulo state, southeastern Brazil, were captured and euthanised, and collected tissues (heart and pectoral muscle) were processed for each bat or in pools of two or three bats and bioassayed in mice (a total of 283 bioassays). Eleven PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) markers were used to genotype positive samples: SAG1, SAG2 (5'-3'SAG2 and alt. SAG2), SAG3, BTUB, GRA6, L358, c22-8, c29-2, PK1, CS3 and Apico. The parasite was isolated from two bats from São Paulo city: an insectivorous bat, the velvety free-tailed bat Molossus molossus, and a hematophagous bat, the common vampire bat Desmodus rotundus. Isolates were designated TgBatBr1 and TgBatBr2, respectively. The genotype of the isolate from M. molossus (TgBatBr1) has been previously described in an isolate from a capybara from São Paulo state, and the genotype from the D. rotundus isolate (TgBatBr2) has already been identified in isolates from cats, chickens, capybaras, sheep, a rodent and a common rabbit from different Brazilian states, suggesting that this may be a common T. gondii lineage circulating in some Brazilian regions. Isolation of T. gondii from a hematophagous species is striking. This study reveals that bats can share the same isolates that are found in domesticated and wild terrestrial animals. This is the first report of the isolation and genotyping of T. gondii in chiropterans. PMID:23200751

  5. Remarques sur la systématique des Palaeomerycidae (Cervoidea, Artiodactyla, mammalia) d'Europe

    NASA Astrophysics Data System (ADS)

    Ginsburg, Léonard

    1999-11-01

    The revision of the European Palaeomerycidae leads us to consider that there are only two species of Palaeomeryx in Europe: Palaeomeryx bojani and Palaeomeryx eminens. On the other hand the genera Triceromeryx, Ampelomeryx and Tauromeryx must be considered as junior synonyms of Palaeomeryx.

  6. The "Linh Duong" Pseudonovibos spiralis (Mammalia, Artiodactyla) is a new buffalo

    NASA Astrophysics Data System (ADS)

    Kuznetsov, G. V.; Kulikov, E. E.; Petrov, N. B.; Ivanova, N. V.; Lomov, A. A.; Kholodova, M. V.; Poltaraus, A. B.

    2001-03-01

    The controversial phylogenetic position of the recently described South-East Asian endemic bovid, Pseudonovibos spiralis, was evaluated on the basis of phylogenetic analyses of originally obtained nearly complete 12S mitochondrial rDNA sequences for this species and Bubalus bubalis and 26 sequences of Bovidae from the Genbank using Cervus elaphus (Cervidae) as outgroup. In most of the phylogenetic analyses performed using PAUP 4.0 (maximum parsimony, maximum likelihood and neighbour-joining), Bovidae consisted of two major clades: Bovinae including the tribes Bovini, Tragelaphini and Boselaphini, and Antilopinae+Caprinae, incorporating all other bovids. In most trees P. spiralis fell within the buffalos (subtribe Bovina) between Bubalus and Syncerus. Therefore, our phylogenetic analyses of bovid mitochondrial 12S rRNA gene sequences suggest the close relationship of this enigmatic species with the buffalos and its placement within the subtribe Bovina.

  7. Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae).

    PubMed

    Matte, Eunice M; Castilho, Camila S; Miotto, Renata A; Sana, Denis A; Johnson, Warren E; O'Brien, Stephen J; de Freitas, Thales R O; Eizirik, Eduardo

    2013-12-01

    The puma is an iconic predator that ranges throughout the Americas, occupying diverse habitats. Previous phylogeographic analyses have revealed that it exhibits moderate levels of genetic structure across its range, with few of the classically recognized subspecies being supported as distinct demographic units. Moreover, most of the species' molecular diversity was found to be in South America. To further investigate the phylogeographic structure and demographic history of pumas we analyzed mtDNA sequences from 186 individuals sampled throughout their range, with emphasis on South America. Our objectives were to refine the phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent. The estimated demographic history supports the interpretation that pumas suffered a severe demographic decline in the Late Pleistocene throughout their distribution, followed by population expansion and re-colonization of the range, initiating from South America. PMID:24385863

  8. Histological patterns of the intestinal attachment of Corynosoma australe (Acanthocephala: Polymorphidae) in Arctocephalus australis (Mammalia: Pinnipedia).

    PubMed

    Silva, Renato Z; Pereira, Joaber; Cousin, Joo Carlos B

    2014-12-01

    The mucosal attachment pattern of Corynosoma australe in the intestines of Arctocephalus australis is described. Normal and abnormal tissue were sampled from 32 hosts to be submitted to histological routine protocol to embedding in paraffin and permanent mounting in balsam. Corynosoma australe shows three different degrees of body depth intestinal attachment (BDINA-1-3). BDINA-1: it is exclusive of the small intestine and the parasite attaches on the villi; BDINA-2: parasite affects the Lieberkhn crypts in several depth levels and, BDINA-3: the parasite reaches the submucosa. These attachment patterns alter the mucosa by degeneration and dysfunction due to necrosis of mucosal structure, great quantities of cellular debris and significant reduction of the mucosal thickness. Other aspects are crater-like concave holes (CLCHs) as sites where C. australe could be attached-detached several times according to adult migratory processes within luminal intestine space. The submucosa shows edema probably due to the local mucosal alterations resulting in homeostatic break. There is no severe inflammatory response by host but BDINA-1 to BDINA-3 and CLCH could represent foci to secondary opportunistic infections and significant areas of malabsorption in severally infected hosts contributing to increase clinical signs of preexistent pathologies. PMID:25320494

  9. Virtual endocranial cast of earliest Eocene Diacodexis (Artiodactyla, Mammalia) and morphological diversity of early artiodactyl brains

    PubMed Central

    Orliac, M. J.; Gilissen, E.

    2012-01-01

    The study of brain evolution, particularly that of the neocortex, is of primary interest because it directly relates to how behavioural variations arose both between and within mammalian groups. Artiodactyla is one of the most diverse mammalian clades. However, the first 10 Myr of their brain evolution has remained undocumented so far. Here, we used high-resolution X-ray computed tomography to investigate the endocranial cast of Diacodexis ilicis of earliest Eocene age. Its virtual reconstruction provides unprecedented access to both metric parameters and fine anatomy of the most complete endocast of the earliest artiodactyl. This picture is assessed in a broad comparative context by reconstructing endocasts of 14 other Early and Middle Eocene representatives of basal artiodactyls, allowing the tracking of the neocortical structure of artiodactyls back to its simplest pattern. We show that the earliest artiodactyls share a simple neocortical pattern, so far never observed in other ungulates, with an almond-shaped gyrus instead of parallel sulci as previously hypothesized. Our results demonstrate that artiodactyls experienced a tardy pulse of encephalization during the Late Neogene, well after the onset of cortical complexity increase. Comparisons with Eocene perissodactyls show that the latter reached a high level of cortical complexity earlier than the artiodactyls. PMID:22764165

  10. Comparative study of notoungulate (Placentalia, Mammalia) bony labyrinths and new phylogenetically informative inner ear characters

    PubMed Central

    Macrini, Thomas E; Flynn, John J; Ni, Xijun; Croft, Darin A; Wyss, Andr R

    2013-01-01

    The phylogenetic relationships of notoungulates, an extinct group of predominantly South American herbivores, remain poorly resolved with respect to both other placental mammals and among one another. Most previous phylogenetic analyses of notoungulates have not included characters of the internal cranium, not least because few such features, including the bony labyrinth, have been described for members of the group. Here we describe the inner ears of the notoungulates Altitypotherium chucalensis (Mesotheriidae), Pachyrukhos moyani (Hegetotheriidae) and Cochilius sp. (Interatheriidae) based on reconstructions of bony labyrinths obtained from computed tomography imagery. Comparisons of the bony labyrinths of these taxa with the basally diverging notoungulate Notostylops murinus (Notostylopidae), an isolated petrosal from Itabora, Brazil, referred to Notoungulata, and six therian outgroups, yielded an inner ear character matrix of 25 potentially phylogenetically informative characters, 14 of them novel to this study. Two equivocally optimized character states potentially support a pairing of Mesotheriidae and Hegetotheriidae, whereas four others may be diagnostic of Notoungulata. Three additional characters are potentially informative for diagnosing more inclusive clades: one for crown Placentalia; another for a clade containing Kulbeckia, Zalambdalestes, and Placentalia; and a third for Eutheria (crown Placentalia plus stem taxa). Several other characters are apomorphic for at least one notoungulate in our study and are of potential interest for broader taxonomic sampling within Notoungulata to clarify currently enigmatic interrelationships. Measures of the semicircular canals were used to infer agility (e.g. capable of quick movements vs. lethargic movements) of these taxa. Agility scores calculated from these data generally corroborate interpretations based on postcranial remains of these or closely related species. We provide estimates of the low-frequency hearing limits in notoungulates based on the ratio of radii of the apical and basal turns of the cochlea. These limits range from 15 Hz in Notostylops to 149 Hz in Pachyrukhos, values comparable to the Asian elephant (Elephas maximus) and the California sea lion (Zalophus californianus) when hearing in air, respectively. PMID:24102069

  11. New fauna of archaeocete whales (Mammalia, Cetacea) from the Bartonian middle Eocene of southern Morocco

    NASA Astrophysics Data System (ADS)

    Gingerich, Philip D.; Zouhri, Samir

    2015-11-01

    Six genera and species of archaic whales are present in a new fauna from the Aridal Formation at Gueran in the Sahara Desert of southwestern Morocco. Three of the archaeocete species represent semiaquatic Protocetidae and three species are fully aquatic Basilosauridae. Protocetids are characteristic of Lutetian lower middle Eocene strata, and basilosaurids are characteristic of Priabonian late Eocene beds. Similar representation of both families is restricted to intervening Bartonian strata and indicative of a late middle Eocene age. Archaeocetes from Gueran include (1) a small protocetid represented by a partial humerus, teeth, and vertebrae; (2) a middle-sized protocetid represented by a partial innominate and proximal femur; (3) the very large protocetid Pappocetus lugardi represented by teeth, a partial innominate, and two partial femora; (4) a new species of the small basilosaurid Chrysocetus represented by a dentary, teeth, humeri, and many vertebrae; (5) a new species of the larger basilosaurid Platyosphys (resurrected as a distinct genus) represented by a partial braincase, tympanic bulla, and many vertebrae; and (6) the large basilosaurid Eocetus schweinfurthi represented by teeth, a tympanic bulla, and lumbar vertebrae. The Gueran locality is important geologically because it constrains the age of a part of the Aridal Formation, and biologically because it includes a diversity of archaic whales represented by partial skeletons with vertebrae in sequence and by forelimb and hind limb remains. With further collecting, Gueran archaeocete skeletons promise to clarify the important evolutionary transition from foot-powered swimming in Protocetidae to the tail-powered swimming of Basilosauridae and all later Cetacea.

  12. Phylogeography and population genetics of the endangered Amazonian manatee, Trichechus inunguis Natterer, 1883 (Mammalia, Sirenia).

    PubMed

    Cantanhede, Andra Martins; Da Silva, Vera Maria Ferreira; Farias, Izeni Pires; Hrbek, Tomas; Lazzarini, Stella Maris; Alves-Gomes, Jos

    2005-02-01

    We used mitochondrial DNA control region sequences to examine phylogeography and population differentiation of the endangered Amazonian manatee Trichechus inunguis. We observe lack of molecular differentiation among localities and we find weak association between geographical and genetic distances. However, nested clade analysis supports restricted gene flow and/or dispersal with some long-distance dispersal. Although this species has a history of extensive hunting, genetic diversity and effective population sizes are relatively high when compared to the West Indian manatee Trichechus manatus. Patterns of mtDNA haplotype diversity in T. inunguis suggest a genetic disequilibrium most likely explained by demographic expansion resulting from secession of hunting and enforcement of conservation and protective measures. Phylogenetic analysis of T. manatus and T. inunguis haplotypes suggests that T. inunguis is nested within T. manatus, effectively making T. manatus a paraphyletic entity. Paraphyly of T. manatus and recent divergence times of T. inunguis and the three main T. manatus lineages suggest a possible need for a taxonomic re-evaluation of the western Atlantic Trichechus. PMID:15660933

  13. The evolution of orbit orientation and encephalization in the Carnivora (Mammalia)

    PubMed Central

    Finarelli, John A; Goswami, Anjali

    2009-01-01

    Evolutionary change in encephalization within and across mammalian clades is well-studied, yet relatively few comparative analyses attempt to quantify the impact of evolutionary change in relative brain size on cranial morphology. Because of the proximity of the braincase to the orbits, and the inter-relationships among ecology, sensory systems and neuroanatomy, a relationship has been hypothesized between orbit orientation and encephalization for mammals. Here, we tested this hypothesis in 68 fossil and living species of the mammalian order Carnivora, comparing orbit orientation angles (convergence and frontation) to skull length and encephalization. No significant correlations were observed between skull length and orbit orientation when all taxa were analysed. Significant correlations were observed between encephalization and orbit orientation; however, these were restricted to the families Felidae and Canidae. Encephalization is positively correlated with frontation in both families and negatively correlated with convergence in canids. These results indicate that no universal relationship exists between encephalization and orbit orientation for Carnivora. Braincase expansion impacts orbit orientation in specific carnivoran clades, the nature of which is idiosyncratic to the clade itself. PMID:19438762

  14. Cranial functional morphology of fossil dogs and adaptation for durophagy in Borophagus and Epicyon (Carnivora, Mammalia).

    PubMed

    Tseng, Zhijie Jack; Wang, Xiaoming

    2010-11-01

    Morphological specialization is a complex interplay of adaptation and constraint, as similarly specialized features often evolve convergently in unrelated species, indicating that there are universally adaptive aspects to these morphologies. The evolutionary history of carnivores offers outstanding examples of convergent specialization. Among larger predators, borophagine canids were highly abundant during the tertiary of North America and are regarded as the ecological vicars of Afro-Eurasian hyenas. Borophaginae is an extinct group of 60+ species, the largest forms evolving robust skulls with prominently domed foreheads, short snouts, and hypertrophied fourth premolars. These specializations have been speculated to enhance bone cracking. To test the extent that the skulls of derived borophagines were adapted for producing large bite forces and withstanding the mechanical stresses associated with bone cracking relative to their nonrobust sister clades, we manipulated muscle forces in models of six canid skulls and analyzed their mechanical response using 3D finite element analysis. Performance measures of bite force production efficiency and deformation minimization showed that skulls of derived borophagines Borophagus secundus and Epicyon haydeni are particularly strong in the frontal region; maximum stresses are lower and more evenly distributed over the skull than in other canids. Frontal strength is potentially coupled with a temporalis-driven bite to minimize cranial stress during biting in the two derived genera, as tensile stress incurred by contracting temporalis muscles is dissipated rostro-ventrally across the forehead and face. Comparison of estimated masticatory muscle cross section areas suggests that the temporalis-masseter ratio is not strongly associated with morphological adaptations for bone cracking in Borophagus and Epicyon; larger body size may explain relatively larger temporalis muscles in the latter. When compared with previous studies, the overall cranial mechanics of the derived borophagines is more similar to bone-cracking hyaenids and percrocutids than to their canid relatives, indicating convergence in both morphological form and functional capability. PMID:20799339

  15. The endemic insular and peninsular species Chaetodipus spinatus (Mammalia, Heteromyidae) breaks patterns for Baja California.

    PubMed

    lvarez-Castaeda, Sergio Ticul; Murphy, Robert W

    2014-01-01

    The Baja California peninsula is the second longest, most geographically isolated peninsula on Earth. Its physiography and the presence of many surrounding islands has facilitated studies of the underlying patterns and drivers of genetic structuring for a wide spectrum of organisms. Chaetodipus spinatus is endemic to the region and occurs on 12 associated islands, including 10 in the Gulf of California and two in the Pacific Ocean. This distribution makes it a model species for evaluating natural historical barriers. We test hypotheses associated with the relationship between the range of the species, patterns in other species, and its relationship to Pleistocene-Holocene climatic changes. We analyzed sequence data from mtDNA genes encoding cytochrome b (Cytb) and cytochrome c oxidase subunits I (COI) and III (COIII) in 26 populations including all 12 islands. The matrilineal genealogy, statistical parsimony network and Bayesian skyline plot indicated an origin of C. spinatus in the southern part of the peninsula. Our analyses detected several differences from the common pattern of peninsular animals: no mid-peninsula break exists, Isla Carmen hosts the most divergent population, the population on an ancient southern Midriff island does not differ from peninsular populations, and a mtDNA peninsular discordance occurs near Loreto. PMID:25542029

  16. Urinary parameters of Trichechus inunguis (Mammalia, Sirenia): reference values for the Amazonian Manatee.

    PubMed

    Pantoja, T M A; Da Rosas, F C W; Dos Silva, V M F; Santos, A M F

    2010-08-01

    The Amazonian manatee, Trichechus inunguis (Natterer 1883) is endemic to the Amazon Basin and is currently considered a vulnerable species. In order to establish normality ranges of urinary parameters to help monitor the health of this species in captivity, chemical urinalyses were performed on twelve males and nine females of various age groups. Urine was collected once a month for twelve months in the tanks just after being drained, by placing stainless steel containers under the genital slit of females and applying abdominal massages to males in order to stimulate urination. Quantitative data of glucose, urea, creatinine, uric acid and amylase levels were obtained using colorimetric spectrophotometry. Dip strips were also useful for routine analyses, despite only providing qualitative results. Normal range to glucose levels, regardless of sex or age class, was 3.0 to 3.6 mgxdL-1, coinciding with qualitative values of glucose measured by dip strips. Statistical differences observed in some parameter levels suggest that some urine parameters analysed must take into consideration the sex and the age class of the animal studied, being these differences less remarkable in creatinine and amylase levels. To this last one, statistical difference was detected only in the calve's urine (7.0 to 11.5 mgxdL-1) compared to other age classes samples (4.1 to 5.3 mgxdL-1). The results presented here may be used as comparative data in future research on urinalysis in related species. PMID:20730348

  17. The mammary glands of the Amazonian manatee, Trichechus inunguis (Mammalia: Sirenia): morphological characteristics and microscopic anatomy.

    PubMed

    Rodrigues, Fernanda Rosa; da Silva, Vera Maria Ferreira; Barcellos, José Fernando Marques

    2014-08-01

    The mammaries from carcasses of two female Amazonian manatees were examined. Trichechus inunguis possesses two axillary mammaries beneath the pectoral fins, one on each side of the body. Each papilla mammae has a small hole on its apex--the ostium papillare. The mammaries are covered by a stratified squamous keratinized epithelium. The epithelium of the mammary ducts became thinner more deeply in the tissue and varied from stratified to simple cuboidal. There was no evidence of glandular activity or secretion into the ducts of the mammary glands. PMID:24920139

  18. [Genetic variability in Neotropical deer genera (Mammalia: Cervidae) according to DNA microsatellite loci].

    PubMed

    Ruiz-García, Manuel; Martinez-Agüero, María; Alvarez, Diana; Goodman, Simon

    2009-09-01

    Species conservation programs are highly based on analyses of population genetics. We compared eight Neotropical Cervidae (Mazama americana, M. gouzaoubira, M. rufina, Odocoileus virginianus, Hippocamelus antisensis, Pudu mephistopholes, Ozotoceros bezoarticus and Blastoceros dichotomus) and some European and Asian Cervidae (Cervus elaphus, C. nippon, Capreolus capreolus, C. pygargus and Dama dama). The European species C. elaphus was our standard for a high degree of genetic variability: we used a Scottish population originated in the mix of diverse Western European subspecies. On the contrary, Cervus nippon (a population from Scotland with a founder effect) was our standard for a depauperated population. The M. americana, M. gouzaoubira and O. virginianus samples had high diversity values close to our C. elaphus population (H = 0.64, 0.70 and 0.61, respectively), while M. rufina was very low, close to C. nippon. Several sample sets of Mazama and Odocoileus yielded a homozygote excess, probably due to the Wahlund (subdivison) effect. There was no evidence of recent bottleneck events. PMID:19928479

  19. Morphometric variations of laelapine mite (Acari: Mesostigmata) populations infesting small mammals (Mammalia) in Brazil.

    PubMed

    Martins-Hatano, F; Gettinger, D; Manhes, M L; Bergallo, H G

    2012-08-01

    The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata) associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Esprito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Esprito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts. PMID:22990832

  20. Observations on fur development in echidna (Monotremata, Mammalia) indicate that spines precede hairs in ontogeny.

    PubMed

    Alibardi, Lorenzo; Rogers, George

    2015-04-01

    In the primitive mammal echidna, the initial 2-3 generations of skin appendages produced from birth forms spines and only later true hairs appear. Microscopy on preserved museum specimens reveals that the morphogenesis of spines and hairs is similar but that a larger dermal papilla is formed in spines. The growing shaft comprises a medulla surrounded by a cortex and by an external cuticle. A thick inner root sheath made of cornified cells surrounds the growing shaft inside the spine canal that eventually exits with a pointed tip. Hairs develop later with the same modality of spines but have a smaller papilla and give rise to a fur coat among spines. Therefore the integument of developing echidnas initially produces spines from large dermal papillae but the reduction in size of the papillae later determines the formation of hairs. Although the morphogenesis of spines and hairs can represent a case of specialization in this species, the primitive mammalian characteristics of echidnas has also inspired new speculations on the evolution of the mammalian hair from mammalian-like reptiles with a spiny coat. The resemblance in the morphogenesis between spines and hairs has suggested some hypothesis on hair evolution, in particular that hairs might be derived from the reduction of protective large spines present in ancient mammalian-like reptiles possibly derived from the reduction of pre-existing pointed scales. The hypothesis suggests that spines became reduced and internalized in the skin forming hairs. PMID:25367156

  1. Biology and impacts of Pacific island invasive species 9. Capra hircus, the feral goat, (Mammalia: Bovidae)

    USGS Publications Warehouse

    Chynoweth, Mark W.; Litton, Creighton M.; Lepczyk, Christopher A.; Hess, Steve A.; Cordell, Susan

    2013-01-01

    Domestic goats, Capra hircus, were intentionally introduced to numerous oceanic islands beginning in the sixteenth century. The remarkable ability of C. hircus to survive in a variety of conditions has enabled this animal to become feral and impact native ecosystems on islands throughout the world. Direct ecological impacts include consumption and trampling of native plants, leading to plant community modification and transformation of ecosystem structure. While the negative impacts of feral goats are well-known and effective management strategies have been developed to control this invasive species, large populations persist on many islands. This review summarizes the impacts of feral goats on Pacific island ecosystems, and the management strategies available to control this invasive species.

  2. Osteoderm histology of the Pampatheriidae (Cingulata, Xenarthra, Mammalia): Implications for systematics, osteoderm growth, and biomechanical adaptation.

    PubMed

    Wolf, Dominik; Kalthoff, Daniela C; Sander, P Martin

    2012-04-01

    Pampatheres are extinct, large-bodied cingulates, which share morphological characters with both armadillos and glyptodonts but are considered to be more closely related to the latter. The osteoderm histology of six pampathere taxa was examined and compared to the histology of other cingulate osteoderms. This study investigates the development and functional adaptation of pampathere osteoderms as well as the phylogenetic relationships of the Pampatheriidae within the Cingulata. We found that pampathere osteoderms share a uniform histological organization based on a basic diploe-like structure. After initial stages of intramembranous growth, metaplastic ossification, that is, the direct incorporation and mineralization of pre-existing protein fibers, plays an important role in osteoderm development and provides information on various kinds of soft tissue otherwise not preserved. The latest stages of osteoderm growth are dominated by periosteal bone formation especially in the superficial cortex. Movable band osteoderms show regular arrangements of incorporated fibers that may increase the resistance of particularly weak areas against strain. The histological composition of pampathere osteoderms is plesiomorphic in its basic structure but shows a number of derived features. A unique array of Sharpey's fibers that are incorporated into the bone matrix at sutured osteoderm margins is interpreted as a synapomorphy of pampatheres. The arrangement of dermal fibers in the deep and superficial cortexes supports the close relationship between pampatheres and glyptodonts. PMID:22045687

  3. Chromosome painting among Proboscidea, Hyracoidea and Sirenia: Support for Paenungulata (Afrotheria, Mammalia) but not Tethytheria

    USGS Publications Warehouse

    Pardini, A.T.; O'Brien, P. C. M.; Fu, B.; Bonde, R.K.; Elder, F.F.B.; Ferguson-Smith, M. A.; Yang, F.; Robinson, T.J.

    2007-01-01

    Despite marked improvements in the interpretation of systematic relationships within Eutheria, particular nodes, including Paenungulata (Hyracoidea, Sirenia and Proboscidea), remain ambiguous. The combination of a rapid radiation, a deep divergence and an extensive morphological diversification has resulted in a limited phylogenetic signal confounding resolution within this clade both at the morphological and nucleotide levels. Cross-species chromosome painting was used to delineate regions of homology between Loxodonta africana (2n = 56), Procavia capensis (2n=54), Trichechus manatus latirostris (2n = 48) and an outgroup taxon, the aardvark (Orycteropus afer, 2n = 20). Changes specific to each lineage were identified and although the presence of a minimum of 11 synapomorphies confirmed the monophyly of Paenungulata, no change characterizing intrapaenungulate relationships was evident. The reconstruction of an ancestral paenungulate karyotype and the estimation of rates of chromosomal evolution indicate a reduced rate of genomic repatterning following the paenungulate radiation. In comparison to data available for other mammalian taxa, the paenungulate rate of chromosomal evolution is slow to moderate. As a consequence, the absence of a chromosomal character uniting two paenungulates (at the level of resolution characterized in this study) may be due to a reduced rate of chromosomal change relative to the length of time separating successive divergence events. ?? 2007 The Royal Society.

  4. Taxonomic and systematic revisions to the North American Nimravidae (Mammalia, Carnivora).

    PubMed

    Barrett, Paul Z

    2016-01-01

    The Nimravidae is a family of extinct carnivores commonly referred to as "false saber-tooth cats." Since their initial discovery, they have prompted difficulty in taxonomic assignments and number of valid species. Past revisions have only examined a handful of genera, while recent advances in cladistic and morphometric analyses have granted us additional avenues to answering questions regarding our understanding of valid nimravid taxa and their phylogenetic relationships. To resolve issues of specific validity, the phylogenetic species concept (PSC) was utilized to maintain consistency in diagnosing valid species, while simultaneously employing character and linear morphometric analyses for confirming the validity of taxa. Determined valid species and taxonomically informative characters were then employed in two differential cladistic analyses to create competing hypotheses of interspecific relationships. The results suggest the validity of twelve species and six monophyletic genera. The first in depth reviews of Pogonodon and Dinictis returned two valid species (P. platycopis, P. davisi) for the former, while only one for the latter (D. felina). The taxonomic validity of Nanosmilus is upheld. Two main clades with substantial support were returned for all cladistic analyses, the Hoplophoneini and Nimravini, with ambiguous positions relative to these main clades for the European taxa: Eofelis, Dinailurictis bonali, and Quercylurus major; and the North American taxa Dinictis and Pogonodon. Eusmilus is determined to represent a non-valid genus for North American taxa, suggesting non-validity for Old World nimravid species as well. Finally, Hoplophoneus mentalis is found to be a junior synonym of Hoplophoneus primaevus, while the validity of Hoplophoneus oharrai is reinstated. PMID:26893959

  5. Revision of the Wind River faunas, early Eocene of central Wyoming. X - Bunophorus (Mammalia, Artiodactyla)

    NASA Technical Reports Server (NTRS)

    Stucky, Richard K.; Krishtalka, Leonard

    1990-01-01

    Research on the holotypes and large collections of the species of Wasatchia and Bunophorus is reviewed. It is concluded that Bunophorus is a senior synonym of Wasatchia and includes six valid species, namely, B. etsagicus, B. grangeri, B. pattersoni, B. macropternus, B. sinclairi, and B. robustus. B. sinclairi includes two penecontemporaneous geographic variants: B.s. sinclairi from the Wind River, Piceance and Green River basins, and B.s. robinsoni, n. ssp., from the Huerfano Basin.

  6. Nucleolus organizer regions and B-chromosomes of wood mice (mammalia, rodentia, Apodemus)

    SciTech Connect

    Boeskorov, G.G.; Kartavtseva, I.V.; Zagorodnyuk, I.V.; Belyanin, A.N.; Lyapunova, E.A.

    1995-02-01

    Distribution of nucleolus organizer regions (NORs) in karyotypes was studied in 10 species of wood mice, including Apodemus flavicollis, A. sylvaticus, A. uralensis (=A. microps), A. fulvipectus (=A. falzfeini), A. ponticus, A. hyrcanicus, A. mystacinus, A. agrarius, A. peninsulae, and A. speciosus. Peculiarities of NOR location in karyotypes can be used in interspecific diagnostics of wood mice. Intraspecific polymorphism of A. sylvaticus, A. agrarius, and A. peninsulae in terms of the number of NORs and their localization in chromosomes can serve as evidence for karyological differentiation in certain populations of these species. The minimum number of active NORs in mice of the genus Apodemus is two to four. Two A. flavicollis wood mice with karyotypes containing one small acrocentric B-chromosome (2n = 49) were identified among animals captured in Estonia. In A. peninsulae, B-chromosomes were found among animals captured in the following regions: the vicinity of Kyzyl (one mouse with 17 microchromosomes, 2n = 65); the vicinity of Birakan (two mice with one metacentric chromosome each, 2n = 49); and in the Ussuri Nature Reserve (one mouse with five B-chromosomes, including three metacentric and two dotlike chromosomes; 2n = 53). In the latter animal, the presence of NORs on two metacentric B-chromosomes was revealed; this is the first case of identification of active NORs on extra chromosomes of mammals. 29 refs., 4 figs., 1 tab.

  7. The Hand of Cercopithecoides williamsi (Mammalia, Primates): Earliest Evidence for Thumb Reduction among Colobine Monkeys

    PubMed Central

    Frost, Stephen R.; Gilbert, Christopher C.; Pugh, Kelsey D.; Guthrie, Emily H.; Delson, Eric

    2015-01-01

    Thumb reduction is among the most important features distinguishing the African and Asian colobines from each other and from other Old World monkeys. In this study we demonstrate that the partial skeleton KNM-ER 4420 from Koobi Fora, Kenya, dated to 1.9 Ma and assigned to the Plio-Pleistocene colobine species Cercopithecoides williamsi, shows marked reduction of its first metacarpal relative to the medial metacarpals. Thus, KNM-ER 4420 is the first documented occurrence of cercopithecid pollical reduction in the fossil record. In the size of its first metacarpal relative to the medial metacarpals, C. williamsi is similar to extant African colobines, but different from cercopithecines, extant Asian colobines and the Late Miocene colobines Microcolobus and Mesopithecus. This feature clearly links the genus Cercopithecoides with the extant African colobine clade and makes it the first definitive African colobine in the fossil record. The postcranial adaptations to terrestriality in Cercopithecoides are most likely secondary, while ancestral colobinans (and colobines) were arboreal. Finally, the absence of any evidence for pollical reduction in Mesopithecus implies either independent thumb reduction in African and Asian colobines or multiple colobine dispersal events out of Africa. Based on the available evidence, we consider the first scenario more likely. PMID:25993410

  8. Mandible shape and dwarfism in squirrels (Mammalia, Rodentia): interaction of allometry and adaptation.

    PubMed

    Hautier, Lionel; Fabre, Pierre-Henri; Michaux, Jacques

    2009-06-01

    Squirrels include several independent lineages of dwarf forms distributed into two ecological groups: the dwarf tree and flying squirrels. The mandible of dwarf tree squirrels share a highly reduced coronoid process and a condylar process drawn backwards. Dwarf flying squirrels on the other hand, have an elongated coronoid process and a well-differentiated condylar process. To interpret such a difference, Elliptic Fourier Transform was used to evaluate how mandible shape varies with dwarfism in sciurids. The results obtained show that this clear-cut difference cannot be explained by a simple allometric relationship in relation with size decrease. We concluded that the retention of anteriorly positioned eye sockets, in relation with distance estimation, allowed the conservation of a well-differentiated coronoid process in all flying species, despite the trend towards its reduction observed among sciurids as their size decreases. PMID:19288073

  9. Philodryas chamissonis (Reptilia: Squamata: Colubridae) preys on the arboreal marsupial Dromiciops gliroides (Mammalia: Microbiotheria: Microbiotheriidae).

    PubMed

    Muoz-Leal, S; Ardiles, K; Figueroa, R A; Gonzlez-Acua, D

    2013-02-01

    Philodryas chamissonis, the Chilean long-tailed snake, is a diurnal predator mainly of Liolaemus lizards, but also of amphibians, birds, rodents and juvenile rabbits. Dromiciops gliroides (Colocolo opossum) is an arboreal marsupial endemic of temperate rainforest of southern South America. Little information is available about this marsupial's biology and ecology. Here we report the predation of one Colocolo opossum by an adult female P. chamissonis in a mixed Nothofagus forest, composed mainly by N. dombeyi, N. glauca and N. alpina trees, in the "Huemules de Niblinto" National Reserve, Nevados de Chilln, Chile. Since these two species have different activity and habitat use patterns, we discuss how this encounter may have occurred. Although it could just have been an opportunistic event, this finding provides insights into the different components of food chains in forest ecosystems of Chile. PMID:23644784

  10. A late-surviving apatemyid (Mammalia: Apatotheria) from the latest Oligocene of Florida, USA

    PubMed Central

    Morgan, Gary S.

    2015-01-01

    A new species of Apatemyidae, Sinclairella simplicidens, is based on four isolated teeth that were screenwashed from fissure fillings at the late Oligocene Buda locality, Alachua County, Florida. Compared to its only congener Sinclairella dakotensis, the new species is characterized by upper molars with more simplified crowns, with the near absence of labial shelves and stylar cusps except for a strong parastyle on M1, loss of paracrista and paraconule on M2 (paraconule retained but weak on M1), lack of anterior cingulum on M1–M3, straighter centrocristae, smaller hypocone on M1 and M2, larger hypocone on M3, distal edge of M2 continuous from hypocone to postmetacrista supporting a large posterior basin, and with different tooth proportions in which M2 is the smallest rather than the largest molar in the toothrow. The relatively rare and poorly-known family Apatemyidae has a long temporal range in North America from the late Paleocene (early Tiffanian) to early Oligocene (early Arikareean). The new species from Florida significantly extends this temporal range by roughly 5 Ma to the end of the Paleogene near the Oligocene-Miocene boundary (from early Arikareean, Ar1, to late Arikareean, Ar3), and greatly extends the geographic range of the family into eastern North America some 10° of latitude farther south and 20° of longitude farther east (about 2,200 km farther southeast) than previously known. This late occurrence probably represents a retreat of this subtropically adapted family into the Gulf Coastal Plain subtropical province at the end of the Paleogene and perhaps the end of the apatemyid lineage in North America. PMID:26713254

  11. Predicting the potential distribution of Vexillata (Nematoda: Ornithostrongylidae) and its hosts (Mammalia: Rodentia) within America.

    PubMed

    Martínez-Salazar, E A; Escalante, T; Linaje, M; Falcón-Ordaz, J

    2013-12-01

    Species distribution modelling has been a powerful tool to explore the potential distribution of parasites in wildlife, being the basis of studies on biogeography. Vexillata spp. are intestinal nematodes found in several species of mammalian hosts, such as rodents (Geomyoidea) and hares (Leporidae) in the Nearctic and northern Neotropical regions. In the present study, we modelled the potential distribution of Vexillata spp. and their hosts, using exclusively species from the Geomyidae and Heteromyidae families, in order to identify their distributional patterns. Bioclimatic and topographic variables were used to identify and predict suitable habitats for Vexillata and its hosts. Using these models, we identified that temperature seasonality is a significant environmental factor that influences the distribution of the parasite genus and its host. In particular, the geographical distribution is estimated to be larger than that predicted for its hosts. This suggests that the nematode has the potential to extend its geographical range and also its spectrum of host species. Increasing sample size and geographical coverage will contribute to recommendations for conservation of this host-parasite system. PMID:23046734

  12. Presence of antibodies against Leptospira serovars in Chaetophractus villosus (Mammalia, Dasypodidae), La Pampa province, Argentina.

    PubMed

    Kin, Marta S; Brihuega, Bibiana; Fort, Marcelo; Delgado, Fernando; Bedotti, Daniel; Casanave, Emma B

    2015-01-01

    Leptospirosis is a zoonosis of worldwide distribution. The aim of this study was to examine the presence of antibodies against 21 Leptospira reactive serovars in Chaetophractus villosus in La Pampa province, Argentina, using the microscopic agglutination test (MAT). Pathologic changes compatible with leptospirosis and in situ detection of the agent by immunohistochemistry were studied in 24 and 3 individuals respectively. Only 35/150 (23.3%) serum samples had antibodies against Leptospira sp. Six percent of the samples reacted with serovar Canicola, 4.7% with serovar Castellonis, 1.3% with serovar Icterohemorrhagieae and 0.7% with serovar Hardjo. Sixteen (10.6%) serum samples agglutinated with Castellonis-Icterohemorrhagiae and Canicola-Castellonis serovars, both with 4.7%, and Canicola-Hardjo and Castellonis-Canicola-Icterohemorrhagiae both with 0.6%. Fourteen animals had variable degrees of lesions, which were more severe in animals with higher serological titers (3200), and Leptospira sp. was detected in 3 animals by immunohistochemistry. These results represent the first record of the presence of Leptospira in C. villosus in La Pampa. PMID:25754485

  13. Reproductive anatomy of the female Amazonian manatee Trichechus inunguis Natterer, 1883 (Mammalia: Sirenia).

    PubMed

    Rodrigues, Fernanda Rosa; Da Silva, Vera Maria Ferreira; Barcellos, Jos Fernando Marques; Lazzarini, Stella Maris

    2008-05-01

    The Amazonian manatee (Trichechus inunguis) is uniparous and has a slow reproduction cycle due to a long gestation period and long interval between births. Even though protected by law, hunting remains one of the main causes hindering the natural population growth of this species in the wild. The histology and reproductive anatomy provide information on the history and reproductive status of the female and offer a tool for the conservation of the species. The present study describes the anatomy of the female reproductive tract in T. inunguis. It is based on materials from three reproductive tracts fixed in 10% buffered formalin. The ovaries, uterine tubes, uterus, vagina, and external genitalia are described. The hymen presents two tiny openings separated by a segment that, upon rupturing during the first copulation, should make up a single vaginal opening. A still intact hymen and the absence of placental scars in the uterus were found in one specimen. Additionally, the presence of a hemorrhagic body and Graafian follicles on the right ovary were observed, as well as whitish scars and among them, possible corpora albicantia. These findings suggest that T. inunguis undergoes infertile estrus cycles before its first gestation. Macroscopically, counting of the whitish scars is hindered by the small diameter of these structures. It is not possible to differentiate between the scars resulting from ruptured (corpora albicantia) and nonruptured follicles (regressed corpora atretica). The presence of whitish scars on both ovaries of the same specimen suggests their bilateral function in T. inunguis. PMID:18383272

  14. Late cenozoic history of the genus Micromys (mammalia, rodentia) in Central Europe.

    PubMed

    Hor?ek, Ivan; Knitlov, Markta; Wagner, Jan; Kordos, Lszl; Nadachowski, Adam

    2013-01-01

    Molecular phylogeography suggests that Micromys minutus, the sole extant species of the genus, colonized its extensive range quite recently, during the Late Pleistocene-Holocene period. Rich Pliocene and Pleistocene fossil records both from Europe and China suggest rather continuous and gradual in situ phenotype rearrangements from the Pliocene to the Recent periods. To elucidate the discrepancy we reexamined a considerable part of the European fossil record of the genus (14 sites from MN15 to Q3, 0.4-4.2 Ma, including the type series of M. preaminutus from MN15 Csarnta 2), analyzed them with the aid of detailed morphometric comparisons, and concluded that: (a) The European Pliocene form, M. praeminutus, differs significantly from the extant species; (b) it exhibits a broad phenotypic variation covering the presumptive diagnostic characters of MN16 M. caesaris; (c) despite having smaller dimensions, the Early and Middle Pleistocene forms (MN17-Q3, 2.6-0.4 Ma) seem to be closer to M. praeminutus than to the extant species; (d) the extinction of M. praeminutus during Q3 and the re-occupation of its niche by the recent expansion of M. minutus from E-European-C Asiatic sources (suggested by phylogeographic hypotheses) cannot be excluded. Discussing interpretations of the phylogenetic past of the genus we emphasize the distinct history of the West Palearctic clade (Late Miocene-Early Pleistocene) terminating with M. praeminutus and the East Asiatic clade (chalceus, tedfordi, minutus), and the possible identity of the Western clade with the Late Miocene genus Parapodemus. PMID:23671605

  15. First detailed reconstruction of the karyotype of Trachypithecus cristatus (Mammalia: Cercopithecidae)

    PubMed Central

    2013-01-01

    Background The chromosomal homologies of human (Homo sapiens = HSA) and silvered leaf monkey (Trachypithecus cristatus = TCR) have been previously studied by classical chromosome staining and by fluorescence in situ hybridization (FISH) applying chromosome-specific DNA probes of all human chromosomes in the 1980s and 1990s, respectively. Results However, as the resolution of these techniques is limited we used multicolor banding (MCB) at an ~250-band level, and other selected human DNA probes to establish a detailed chromosomal map of TCR. Therefore it was possible to precisely determine evolutionary conserved breakpoints, orientation of segments and distribution of specific regions in TCR compared to HSA. Overall, 69 evolutionary conserved breakpoints including chromosomal segments, which failed to be resolved in previous reports, were exactly identified and characterized. Conclusions This work also represents the first molecular cytogenetic one characterizing a multiple sex chromosome system with a male karyotype 44,XY1Y2. The obtained results are compared to other available data for old world monkeys and drawbacks in hominoid evolution are discussed. PMID:24341374

  16. Identification of Bacterial Specialists in Hosts belonging to Aves, Mammalia, and Pisces

    EPA Science Inventory

    Only a portion of bacteria found in animal guts are able to establish specific associations within animal hosts. Taxa that have formed these specialized relationships may have played a prominent role in host evolution and may also contribute significantly to current host physiolo...

  17. Functional implications of variation in tooth spacing and crown size in pinnipedimorpha (mammalia: carnivora).

    PubMed

    Churchill, Morgan; Clementz, Mark T

    2015-05-01

    Pinnipeds (seals, sea lions, and walruses) show variation in tooth morphology that relates to ecology. However, crown size and spacing are two aspects of morphology that have not been quantified in prior studies. We measured these characters for nearly all extant pinnipeds and three fossil taxa and then determined the principal sources of variation in tooth size and spacing using principal components (PCAs) and hierarchical cluster analysis (HCA). PCA and HCA showed that species sorted into three groups: taxa with small crowns and large diastemata, taxa with large crowns and small diastemata, and taxa that fell between these two extremes. We then performed discriminant function analysis (DFA) to determine if tooth morphology correlated with foraging strategy or diet. DFA results indicated weak correlation with diet, and stronger correlation with prey capture strategies. Tooth size and spacing were most strongly correlated with the importance of teeth in prey acquisition, with tooth size decreasing and tooth spacing increasing as teeth become less necessary in capturing food items. Taxa which relied on teeth for filtering prey from the water column or processing larger or tougher food items generally had larger crowns and smaller tooth spacing then taxa which swallowed prey whole. We found the fossil taxa Desmatophoca and Enaliarctos were most similar in tooth morphology to extant otariids, suggesting that both taxa were generalist feeders. This study established the relationship between tooth size and feeding behavior, and provides a new tool to explore the paleoecology of fossil pinnipeds and other aquatic tetrapods. PMID:25367223

  18. Cope's rule and the evolution of body size in Pinnipedimorpha (Mammalia: Carnivora).

    PubMed

    Churchill, Morgan; Clementz, Mark T; Kohno, Naoki

    2015-01-01

    Cope's rule describes the evolutionary trend for animal lineages to increase in body size over time. In this study, we tested the validity of Cope's rule for a marine mammal clade, the Pinnipedimorpha, which includes the extinct Desmatophocidae, and extant Phocidae (earless seals), Otariidae (fur seals and sea lions), and Odobenidae (walruses). We tested for the presence of Cope's rule by compiling a large dataset of body size data for extant and fossil pinnipeds and then examined how body size evolved through time. We found that there was a positive relationship between geologic age and body size. However, this trend is the result of differences between early assemblages of small-bodied pinnipeds (Oligocene to early Miocene) and later assemblages (middle Miocene to Pliocene) for which species exhibited greater size diversity. No significant differences were found between the number of increases or decreases in body size within Pinnipedimorpha or within specific pinniped clades. This suggests that the pinniped body size increase was driven by passive diversification into vacant niche space, with the common ancestor of Pinnipedimorpha occurring near the minimum adult body size possible for a marine mammal. Based upon the above results, the evolutionary history of pinnipeds does not follow Cope's rule. PMID:25355195

  19. Desmodus rotundus (Mammalia: Chiroptera) on the southern coast of Rio de Janeiro state, Brazil.

    PubMed

    Costa, L M; Esbrard, C E L

    2011-08-01

    Since the 1990s, attacks by hematophagous bats on humans and domestic animals have been reported both on the continent and on the islands on the southern coast of Rio de Janeiro state. The density of vampire bats was investigated based on percentage of captures during control of Desmodus rotundus samplings and during bat diversity research. In the present work, 203 individuals of D. rotundus were captured from 1993 to 2009, which corresponds to 11.88% of all bat captures carried out for species control in local villages and 1.58% of all captures in faunistic inventories. The density of D. rotundus is high even on the recently occupied islands where domestic animals have been introduced. It is probable that this species dispersed from the continent to the islands due to the introduction of domestic animals. PMID:21881799

  20. [Bats (Chiroptera: Mammalia) from Yurubí National Park, Venezuela: taxonomic list and community study].

    PubMed

    Delgado-Jaramillo, Mariana; Machado, Marjorie; García, Franger J; Ochoa, José

    2011-12-01

    Bats represent a key component in the dynamics of many terrestrial ecosystems, and one of the groups of mammals with the highest levels of diversification in the Neotropics. Here we describe the results of a study of the bat fauna from Yurubí National Park (mountain area in Northern Venezuela), that includes a taxonomic list and the characterization of some community attributes in forested areas. Data was collected from zoological collections and diversified sampling methods from February to July of 2009 in an altitudinal gradient (100-1 500m), with three principal ecological units: semideciduous, evergreen and cloud forests. We recorded 64 species grouped in five families (63% of the bats known from La Cordillera de la Costa), of which Phyllostomidae was the dominant taxa (42 species; 66% of total), followed by Vespertilionidae, Molossidae, Emballonuridae and Mormoopidae. The community with the highest taxonomic diversification was found in the lowest elevation range, while the lowest number of species was found at the highest range. Eleven trophic guilds were identified; the insectivorous guild was the richest, whereas the frugivorous was the most abundant. Our results allow us to indicate these forest ecosystems have an appropriate conservation status, taking into account the presence of a relatively high proportion of species from the subfamily Phyllostominae, as well as the presence of other species with conservation priorities. All these aspects, and the fact that this represents a reservoir of the biological diversity of the forest ecosystems of La Cordillera de la Costa, make this protected area of an essential conservation value, in a highly endangered bioregion by neighboring socio-economic growth. PMID:22208091

  1. Late Cenozoic History of the Genus Micromys (Mammalia, Rodentia) in Central Europe

    PubMed Central

    Hor?ek, Ivan; Knitlov, Markta; Wagner, Jan; Kordos, Lszl; Nadachowski, Adam

    2013-01-01

    Molecular phylogeography suggests that Micromys minutus, the sole extant species of the genus, colonized its extensive range quite recently, during the Late Pleistocene-Holocene period. Rich Pliocene and Pleistocene fossil records both from Europe and China suggest rather continuous and gradual in situ phenotype rearrangements from the Pliocene to the Recent periods. To elucidate the discrepancy we reexamined a considerable part of the European fossil record of the genus (14 sites from MN15 to Q3, 0.44.2 Ma, including the type series of M. preaminutus from MN15 Csarnta 2), analyzed them with the aid of detailed morphometric comparisons, and concluded that: (a) The European Pliocene form, M. praeminutus, differs significantly from the extant species; (b) it exhibits a broad phenotypic variation covering the presumptive diagnostic characters of MN16 M. caesaris; (c) despite having smaller dimensions, the Early and Middle Pleistocene forms (MN17-Q3, 2.60.4 Ma) seem to be closer to M. praeminutus than to the extant species; (d) the extinction of M. praeminutus during Q3 and the re-occupation of its niche by the recent expansion of M. minutus from E-European C Asiatic sources (suggested by phylogeographic hypotheses) cannot be excluded. Discussing interpretations of the phylogenetic past of the genus we emphasize the distinct history of the West Palearctic clade (Late Miocene-Early Pleistocene) terminating with M. praeminutus and the East Asiatic clade (chalceus, tedfordi, minutus), and the possible identity of the Western clade with the Late Miocene genus Parapodemus. PMID:23671605

  2. Morphometric study of phylogenetic and ecologic signals in procyonid (mammalia: carnivora) endocasts.

    PubMed

    Ahrens, Heather E

    2014-12-01

    Endocasts provide a proxy for brain morphology but are rarely incorporated in phylogenetic analyses despite the potential for new suites of characters. The phylogeny of Procyonidae, a carnivoran family with relatively limited taxonomic diversity, is not well resolved because morphological and molecular data yield conflicting topologies. The presence of phylogenetic and ecologic signals in the endocasts of procyonids will be determined using three-dimensional geometric morphometrics. Endocasts of seven ingroup species and four outgroup species were digitally rendered and 21 landmarks were collected from the endocast surface. Two phylogenetic hypotheses of Procyonidae will be examined using methods testing for phylogenetic signal in morphometric data. In analyses of all taxa, there is significant phylogenetic signal in brain shape for both the morphological and molecular topologies. However, the analyses of ingroup taxa recover a significant phylogenetic signal for the morphological topology only. These results indicate support for the molecular outgroup topology, but not the ingroup topology given the brain shape data. Further examination of brain shape using principal components analysis and wireframe comparisons suggests procyonids possess more developed areas of the brain associated with motor control, spatial perception, and balance relative to the basal musteloid condition. Within Procyonidae, similar patterns of variation are present, and may be associated with increased arboreality in certain taxa. Thus, brain shape derived from endocasts may be used to test for phylogenetic signal and preliminary analyses suggest an association with behavior and ecology. PMID:25066912

  3. Late Pleistocene carnivores (Carnivora: Mammalia) from a cave sedimentary deposit in northern Brazil.

    PubMed

    Rodrigues, Shirlley; Avilla, Leonardo S; Soibelzon, Leopoldo H; Bernardes, Camila

    2014-12-01

    The Brazilian Quaternary terrestrial Carnivora are represented by the following families: Canidae, Felidae, Ursidae, Procyonidae Mephitidae and Mustelidae. Their recent evolutionary history in South America is associated with the uplift of the Panamanian Isthmus, and which enabled the Great American Biotic Interchange (GABI). Here we present new fossil records of Carnivora found in a cave in Aurora do Tocantins, Tocantins, northern Brazil. A stratigraphical controlled collection in the sedimentary deposit of the studied cave revealed a fossiliferous level where the following Carnivora taxa were present: Panthera onca, Leopardus sp., Galictis cuja, Procyon cancrivorus, Nasua nasua and Arctotherium wingei. Dating by Electron Spinning Resonance indicates that this assemblage was deposited during the Last Glacial Maximum (LGM), at least, 22.000 YBP. The weasel, G. cuja, is currently reported much further south than the record presented here. This may suggest that the environment around the cave was relatively drier during the LGM, with more open vegetation, and more moderate temperatures than the current Brazilian Cerrado. PMID:25590705

  4. Late Pleistocene carnivores (Carnivora: Mammalia) from a cave sedimentary deposit in northern Brazil.

    PubMed

    Rodrigues, Shirlley; Avilla, Leonardo S; Soibelzon, Leopoldo H; Bernardes, Camila

    2014-11-28

    The Brazilian Quaternary terrestrial Carnivora are represented by the following families: Canidae, Felidae, Ursidae, Procyonidae Mephitidae and Mustelidae. Their recent evolutionary history in South America is associated with the uplift of the Panamanian Isthmus, and which enabled the Great American Biotic Interchange (GABI). Here we present new fossil records of Carnivora found in a cave in Aurora do Tocantins, Tocantins, northern Brazil. A stratigraphical controlled collection in the sedimentary deposit of the studied cave revealed a fossiliferous level where the following Carnivora taxa were present: Panthera onca, Leopardus sp., Galictis cuja, Procyon cancrivorus, Nasua nasua and Arctotherium wingei. Dating by Electron Spinning Resonance indicates that this assemblage was deposited during the Last Glacial Maximum (LGM), at least, 22.000 YBP. The weasel, G. cuja, is currently reported much further south than the record presented here. This may suggest that the environment around the cave was relatively drier during the LGM, with more open vegetation, and more moderate temperatures than the current Brazilian Cerrado. PMID:25424041

  5. The Endemic Insular and Peninsular Species Chaetodipus spinatus (Mammalia, Heteromyidae) Breaks Patterns for Baja California

    PubMed Central

    Álvarez-Castañeda, Sergio Ticul; Murphy, Robert W.

    2014-01-01

    The Baja California peninsula is the second longest, most geographically isolated peninsula on Earth. Its physiography and the presence of many surrounding islands has facilitated studies of the underlying patterns and drivers of genetic structuring for a wide spectrum of organisms. Chaetodipus spinatus is endemic to the region and occurs on 12 associated islands, including 10 in the Gulf of California and two in the Pacific Ocean. This distribution makes it a model species for evaluating natural historical barriers. We test hypotheses associated with the relationship between the range of the species, patterns in other species, and its relationship to Pleistocene-Holocene climatic changes. We analyzed sequence data from mtDNA genes encoding cytochrome b (Cytb) and cytochrome c oxidase subunits I (COI) and III (COIII) in 26 populations including all 12 islands. The matrilineal genealogy, statistical parsimony network and Bayesian skyline plot indicated an origin of C. spinatus in the southern part of the peninsula. Our analyses detected several differences from the common pattern of peninsular animals: no mid-peninsula break exists, Isla Carmen hosts the most divergent population, the population on an ancient southern Midriff island does not differ from peninsular populations, and a mtDNA peninsular discordance occurs near Loreto. PMID:25542029

  6. Comparative study of notoungulate (Placentalia, Mammalia) bony labyrinths and new phylogenetically informative inner ear characters.

    PubMed

    Macrini, Thomas E; Flynn, John J; Ni, Xijun; Croft, Darin A; Wyss, André R

    2013-11-01

    The phylogenetic relationships of notoungulates, an extinct group of predominantly South American herbivores, remain poorly resolved with respect to both other placental mammals and among one another. Most previous phylogenetic analyses of notoungulates have not included characters of the internal cranium, not least because few such features, including the bony labyrinth, have been described for members of the group. Here we describe the inner ears of the notoungulates Altitypotherium chucalensis (Mesotheriidae), Pachyrukhos moyani (Hegetotheriidae) and Cochilius sp. (Interatheriidae) based on reconstructions of bony labyrinths obtained from computed tomography imagery. Comparisons of the bony labyrinths of these taxa with the basally diverging notoungulate Notostylops murinus (Notostylopidae), an isolated petrosal from Itaboraí, Brazil, referred to Notoungulata, and six therian outgroups, yielded an inner ear character matrix of 25 potentially phylogenetically informative characters, 14 of them novel to this study. Two equivocally optimized character states potentially support a pairing of Mesotheriidae and Hegetotheriidae, whereas four others may be diagnostic of Notoungulata. Three additional characters are potentially informative for diagnosing more inclusive clades: one for crown Placentalia; another for a clade containing Kulbeckia, Zalambdalestes, and Placentalia; and a third for Eutheria (crown Placentalia plus stem taxa). Several other characters are apomorphic for at least one notoungulate in our study and are of potential interest for broader taxonomic sampling within Notoungulata to clarify currently enigmatic interrelationships. Measures of the semicircular canals were used to infer agility (e.g. capable of quick movements vs. lethargic movements) of these taxa. Agility scores calculated from these data generally corroborate interpretations based on postcranial remains of these or closely related species. We provide estimates of the low-frequency hearing limits in notoungulates based on the ratio of radii of the apical and basal turns of the cochlea. These limits range from 15 Hz in Notostylops to 149 Hz in Pachyrukhos, values comparable to the Asian elephant (Elephas maximus) and the California sea lion (Zalophus californianus) when hearing in air, respectively. PMID:24102069

  7. Placentation and fetal membrane development in the South American coati, Nasua nasua (Mammalia, Carnivora, Procyonidae)

    PubMed Central

    2014-01-01

    Background Placental research in carnivores has concentrated on domestic species, which have zonary, labyrinthine placentas with an endotheliochorial barrier. Although the coati, Nasua nasua, is a widely distributed species in South America, data on the development of the placenta and the fetal membranes in this species are very sparse. Findings Four placentas from mid-gestation to near term were collected from wild individuals and were investigated based on gross morphology, histology, immunohistochemistry and electron microscopy. The available data support the concept that the ancestral condition of placentation in carnivores is phylogenetically characterized by a zonary and labyrinthine placental type with an endotheliochorial fetomaternal barrier, comprising extended epitheliochorial and haemochorial zones, such as hemophagous organs for iron supply and histiotrophe uptake and a yolk sac placenta. Conclusions Because of the foundational mechanisms that lead to the considerable complexity of fetomaternal contact zones in carnivores have not been studied, carnivores are interesting animal models for interhaemal barrier differentiation. PMID:24969476

  8. Identification of specialists and abundance-occupancy relationships among intestinal bacteria of Aves, Mammalia, and Actinopterygii

    EPA Science Inventory

    The coalescence of next generation DNA sequencing methods, ecological perspectives, and bioinformatics analysis tools is rapidly advancing our understanding of the evolution and function of vertebrate-associated bacterial communities. Delineating host-microbial associations has a...

  9. Bone Inner Structure Suggests Increasing Aquatic Adaptations in Desmostylia (Mammalia, Afrotheria)

    PubMed Central

    Hayashi, Shoji; Houssaye, Alexandra; Nakajima, Yasuhisa; Chiba, Kentaro; Ando, Tatsuro; Sawamura, Hiroshi; Inuzuka, Norihisa; Kaneko, Naotomo; Osaki, Tomohiro

    2013-01-01

    Background The paleoecology of desmostylians has been discussed controversially with a general consensus that desmostylians were aquatic or semi-aquatic to some extent. Bone microanatomy can be used as a powerful tool to infer habitat preference of extinct animals. However, bone microanatomical studies of desmostylians are extremely scarce. Methodology/Principal Findings We analyzed the histology and microanatomy of several desmostylians using thin-sections and CT scans of ribs, humeri, femora and vertebrae. Comparisons with extant mammals allowed us to better understand the mode of life and evolutionary history of these taxa. Desmostylian ribs and long bones generally lack a medullary cavity. This trait has been interpreted as an aquatic adaptation among amniotes. Behemotops and Paleoparadoxia show osteosclerosis (i.e. increase in bone compactness), and Ashoroa pachyosteosclerosis (i.e. combined increase in bone volume and compactness). Conversely, Desmostylus differs from these desmostylians in displaying an osteoporotic-like pattern. Conclusions/Significance In living taxa, bone mass increase provides hydrostatic buoyancy and body trim control suitable for poorly efficient swimmers, while wholly spongy bones are associated with hydrodynamic buoyancy control in active swimmers. Our study suggests that all desmostylians had achieved an essentially, if not exclusively, aquatic lifestyle. Behemotops, Paleoparadoxia and Ashoroa are interpreted as shallow water swimmers, either hovering slowly at a preferred depth, or walking on the bottom, and Desmostylus as a more active swimmer with a peculiar habitat and feeding strategy within Desmostylia. Therefore, desmostylians are, with cetaceans, the second mammal group showing a shift from bone mass increase to a spongy inner organization of bones in their evolutionary history. PMID:23565143

  10. New species of Agriotherium (Mammalia, Carnivora) from the late Miocene to early Pliocene of central Myanmar

    NASA Astrophysics Data System (ADS)

    Ogino, Shintaro; Egi, Naoko; Zin-Maung-Maung-Thein; Thaung-Htike; Takai, Masanaru

    2011-08-01

    Here we describe a new species of giant short-faced fossil bears, Agriotheriummyanmarensis sp. nov. (Ursidae, Carnivora), from the latest Miocene to early Pliocene Irrawaddy sediments in the Chaingzauk area, central Myanmar. A. myanmarensis has a short mandible and a deep premasseteric fossa, both of which are the typical feature of Agriotherium. There are two specimens discovered so far: in the type specimen the inferior border of the mandibular corpus is rectilinearly-shaped, the m1 talonid is rather reduced, m1 metaconid larger than the entoconid-entoconulid ridge, the diastema between canine and p4 is very short, and the postcanine teeth are so reduced that existing cheek teeth are very crowded. Agriotherium had been widely distributed from the late Miocene through Pleistocene in Europe, East Asia (China), North America, and South Africa, but no fossil record has been reported from Southeast Asia. Except its extreme short snout, A. myanmarensis is most similar to that of the European form, Agriotheriuminsigne, rather than to the Asian species from Siwalik or China, such as Agriotheriumpalaeindicus, Agriotheriumsivalensis, and Agriotheriuminexpetans, suggesting the phylogenetic closeness to the European rather than to the South/East Asian forms.

  11. Effects of different land cover, habitat fragmentation, and ant colonies on the distribution and abundance of shrews in southern California

    USGS Publications Warehouse

    Laakkonen, J.; Fisher, R.N.; Case, T.J.

    2001-01-01

    Eggs or empty shells of the American woodcockwere collected from 10 states in 1971and shell thickness (mean of clutch means) was compared with that of eggs collected from 16 states during the years 1859-1939. The 1971 shells (n = 91) from hatched eggs or those containing fully developed embryos were about i0 percent thinner (P<0.001) than both unembryonated shells (n = 26) from the same year and the 1859-1939 shells (n = 169) from essentially unembryonated eggs. The difference is attributed to the transfer of calcium from the shells to the embryos and not to environmental pollutants.

  12. The differential antiemetic properties of GLP-1 receptor antagonist, exendin (9-39) in Suncus murinus (house musk shrew).

    PubMed

    Chan, Sze Wa; Lu, Zengbing; Lin, Ge; Yew, David Tai Wai; Yeung, Chi Kong; Rudd, John A

    2014-08-01

    The use of glucagon-like peptide-1 (7-36) amide (GLP-1) receptor agonists for the treatment of type 2 diabetes mellitus is commonly associated with nausea and vomiting. Previous studies using Suncus murinus revealed that the GLP-1 receptor agonist, exendin-4, induces emesis via the brainstem and/or hypothalamus. The present study investigated the mechanism of exendin-4-induced emesis in more detail. Ondansetron (1mg/kg, s.c.) and CP-99,994 (10mg/kg, s.c) failed to reduce emesis induced by exendin-4 (3nmol, i.c.v.), suggesting that 5-HT3 and NK1 receptors are not involved in the mechanism. In other studies, the GLP-1 receptor antagonist, exendin (9-39), antagonised emesis and c-Fos expression in the brainstem and the paraventricular hypothalamus induced by the chemotherapeutic drug cisplatin (30mg/kg, i.p.; p<0.05), but not the emesis induced by nicotine (5mg/kg, s.c.; p>0.05), or copper sulphate pentahydrate (120mg/kg, p.o.; p>0.05). GLP-1 receptors may therefore represent a potential target for drugs to prevent chemotherapy-induced emesis in situations where 5-HT3 and NK1 receptor antagonists fail. PMID:24726308

  13. Updating the evolutionary history of Carnivora (Mammalia): a new species-level supertree complete with divergence time estimates

    PubMed Central

    2012-01-01

    Background Although it has proven to be an important foundation for investigations of carnivoran ecology, biology and evolution, the complete species-level supertree for Carnivora of Bininda-Emonds et al. is showing its age. Additional, largely molecular sequence data are now available for many species and the advancement of computer technology means that many of the limitations of the original analysis can now be avoided. We therefore sought to provide an updated estimate of the phylogenetic relationships within all extant Carnivora, again using supertree analysis to be able to analyze as much of the global phylogenetic database for the group as possible. Results In total, 188 source trees were combined, representing 114 trees from the literature together with 74 newly constructed gene trees derived from nearly 45,000 bp of sequence data from GenBank. The greater availability of sequence data means that the new supertree is almost completely resolved and also better reflects current phylogenetic opinion (for example, supporting a monophyletic Mephitidae, Eupleridae and Prionodontidae; placing Nandinia binotata as sister to the remaining Feliformia). Following an initial rapid radiation, diversification rate analyses indicate a downturn in the net speciation rate within the past three million years as well as a possible increase some 18.0 million years ago; numerous diversification rate shifts within the order were also identified. Conclusions Together, the two carnivore supertrees remain the only complete phylogenetic estimates for all extant species and the new supertree, like the old one, will form a key tool in helping us to further understand the biology of this charismatic group of carnivores. PMID:22369503

  14. Generalism as a subsistence strategy: advantages and limitations of the highly flexible feeding traits of Pleistocene Stephanorhinus hundsheimensis (Rhinocerotidae, Mammalia)

    NASA Astrophysics Data System (ADS)

    Kahlke, Ralf-Dietrich; Kaiser, Thomas M.

    2011-08-01

    The so-called Hundsheim rhinoceros, Stephanorhinus hundsheimensis, was a very common faunal element of the Early to early Middle Pleistocene period in the western Palaearctic. In this study, individuals from two different central European populations of the Hundsheim rhinoceros were analysed in order to determine whether their local dietary signals could reflect differing food availability between the two populations, and whether such information could provide a better understanding of the ecological role of S. hundsheimensis within corresponding faunal assemblages, and of its principal subsistence strategy in the western Palaearctic. The mesowear traits observed in the studied S. hundsheimensis populations have been interpreted as representing biome-specific signals, indicating grassland vegetation at the site of Senborn, and dense to open forests at Voigtstedt (both localities in Germany). The analyses performed on the fossil rhino material demonstrate the most pronounced dietary variability ever established for a single herbivorous ungulate species by mesowear studies. This variability ranges from an attrition dominated grazing regime, to a one of predominantly browsing, and characterises S. hundsheimensis as the most ecologically tolerant rhinoceros of the Palaearctic Plio-Pleistocene. Although such dietary flexibility proved an effective enough subsistence strategy over a period of 600-900 ka (1.4/1.2-0.6/0.5 Myr) in the western Palaearctic, the situation changed dramatically after 0.6 Myr BP, when the new species of rhinoceroses, Stephanorhinus hemitoechus and Stephanorhinus kirchbergensis, appeared and started to compete for both the grass and the browse. For the generalist S. hundsheimensis, this bilateral interference was detrimental to its success in all of its habitats. The successful competition of specialised forms of rhinoceroses, which might have originated as a result of the development of 100 ka periodicity in the global climatic record, is proposed as the main reason for the extinction of S. hundsheimensis during the early Middle Pleistocene.

  15. Molecules, morphometrics and new fossils provide an integrated view of the evolutionary history of Rhinopomatidae (Mammalia: Chiroptera)

    PubMed Central

    Hulva, Pavel; Hor?ek, Ivan; Benda, Petr

    2007-01-01

    Background The Rhinopomatidae, traditionally considered to be one of the most ancient chiropteran clades, remains one of the least known groups of Rhinolophoidea. No relevant fossil record is available for this family. Whereas there have been extensive radiations in related families Rhinolophidae and Hipposideridae, there are only a few species in the Rhinopomatidae and their phylogenetic relationship and status are not fully understood. Results Here we present (a) a phylogenetic analysis based on a partial cytochrome b sequence, (b) new fossils from the Upper Miocene site Elaiochoria 2 (Chalkidiki, Greece), which represents the first appearance datum of the family based on the fossil record, and (c) discussion of the phylogeographic patterns in both molecular and morphological traits. We found deep divergences in the Rhinopoma hardwickii lineage, suggesting that the allopatric populations in (i) Iran and (ii) North Africa and the Middle East should have separate species status. The latter species (R. cystops) exhibits a shallow pattern of isolation by distance (separating the Middle East and the African populations) that contrasts with the pattern of geographic variation in the morphometrical traits. A deep genetic gap was also found in Rhinopoma muscatellum (Iran vs. Yemen). We found only minute genetic distance between R. microphyllum from the Levant and India, which fails to support the sub/species distinctness of the Indian form (R. microphyllum kinneari). Conclusion The mtDNA survey provided phylogenetic tree of the family Rhinopomatidae for the first time and revealed an unexpected diversification of the group both within R. hardwickii and R. muscatellum morphospecies. The paleobiogeographic scenario compiled in respect to molecular clock data suggests that the family originated in the region south of the Eocene Western Tethyan seaway or in India, and extended its range during the Early Miocene. The fossil record suggests a Miocene spread into the Mediterranean region, followed by a post-Miocene retreat. Morphological analysis compared with genetic data indicates considerable phenotypic plasticity in this group. PMID:17868440

  16. Molecular phylogenetic reconstructions identify East Asia as the cradle for the evolution of the cosmopolitan genus Myotis (Mammalia, Chiroptera).

    PubMed

    Ruedi, Manuel; Stadelmann, Benot; Gager, Yann; Douzery, Emmanuel J P; Francis, Charles M; Lin, Liang-Kong; Guilln-Servent, Antonio; Cibois, Alice

    2013-12-01

    Sequences of the mitochondrial cytochrome b (1140 bp) and nuclear Rag 2 (1148 bp) genes were used to assess the evolutionary history of the cosmopolitan bat genus Myotis, based on a worldwide sampling of over 88 named species plus 7 species with uncertain nomenclature. Phylogenetic reconstructions of this comprehensive taxon sampling show that most radiation of species occurred independently within each biogeographic region. Our molecular study supports an early divergence of species from the New World, where all Nearctic and Neotropical species plus a lineage from the Palaearctic constitute a monophyletic clade, sister to the remaining Old World taxa. The major Old World clade includes all remaining Eurasian taxa, most Oriental species, one Oceanian, and all Ethiopian species. Another lineage, including M. latirostris from Taiwan, appears at the base of these two major biogeographic clades and, because it bears nyctalodont molars, could be considered as a distinct genus. However, this molar configuration is also found in crown-group species, indicating that these dental characters are variable in the genus Myotis and may confound interpretation of the fossil record. Molecular datings suggest an origin of all recent Myotis in the early Miocene (about 21MYA with 95% highest posterior density interval 23-20MYA). This period was characterized by a global climatic cooling that reduced the availability of tropical habitats and favoured the development of more temperate vegetation. This sharp climatic change might have triggered the evolution of Myotis in the Northern continents, because Myotis ancestors seem to have been well adapted and successful in such temperate habitats. Ancestral area reconstructions based on the molecular phylogeny suggest that the eastern portion of the Asian continent was an important center of origin for the early diversification of all Myotis lineages, and involved relatively few subsequent transcontinental range expansions. PMID:23988307

  17. Genetic divergence and phylogeography in the genus Nyctalus (Mammalia, Chiroptera): implications for population history of the insular bat Nyctalus azoreum.

    PubMed

    Salgueiro, P; Ruedi, M; Coelho, M M; Palmeirim, J M

    2007-06-01

    We used three mitochondrial DNA fragments with different substitution rates (ND1, Cyt b and the CR) to infer phylogenetic relationships among six species of the genus Nyctalus, and compare levels of genetic divergence between the insular, vulnerable Nyctalus azoreum and its continental counterpart to assess the origins of the Azorean bat. The larger species found throughout the Palaearctic region (N. lasiopterus, N. aviator and N. noctula) share a unique chromosome formula (2n=42) and form a monophyletic clade in our reconstructions. Nyctalus plancyi (=velutinus), a Chinese taxon with 2n=36 chromosomes, is sometimes included in N. noctula, but is genetically very divergent from the latter and deserves full species status. All Cyt b and CR haplotypes of N. azoreum are closely related and only found in the Azores archipelago, but when compared to continental sequences of N. leisleri, levels of mtDNA divergence are unusually low for mammalian species. This contrasts with the high level of differentiation that N. azoreum has attained in its morphology, ecology, and echolocation calls, suggesting a recent split followed by fast evolutionary change. The molecular data suggest that N. azoreum originated from a European population of N. leisleri, and that the colonisation of the Azores occurred at the end of the Pleistocene. The Madeiran populations of N. leisleri also appear to have a European origin, whereas those of the Canary Islands probably came from North Africa. In spite of its recent origin and low genetic divergence, the Azorean bat is well differentiated and consequently represents a unique evolutionary unit with great conservation value. PMID:16941086

  18. Island history affects faunal composition: the treeshrews (Mammalia: Scandentia: Tupaiidae) from the Mentawai and Batu Islands, Indonesia

    USGS Publications Warehouse

    Sargis, Eric J.; Woodman, Neal; Morningstar, Natalie C.; Reese, Aspen T.; Olson, Link E.

    2014-01-01

    The Mentawai and Batu Island groups off the west coast of Sumatra have a complicated geological and biogeographical history. The Batu Islands have shared a connection with the Sumatran ‘mainland’ during periods of lowered sea level, whereas the Mentawai Islands, despite being a similar distance from Sumatra, have remained isolated from Sumatra, and probably from the Batu Islands as well. These contrasting historical relationships to Sumatra have influenced the compositions of the respective mammalian faunas of these island groups. Treeshrews (Scandentia, Tupaiidae) from these islands have, at various times in their history, been recognized as geographically circumscribed populations of a broadly distributed Tupaia glis, subspecies, or distinct species. We used multivariate analyses of measurements from the skull and hands to compare the island populations from Siberut (Mentawai Islands) and Tanahbala (Batu Islands) with the geographically adjacent species from the southern Mentawai Islands (T. chrysogaster) and Sumatra (T. ferruginea). Results from both the skull and manus of the Siberut population show that it is most similar to T. chrysogaster, whereas the Tanahbala population is more similar to T. ferruginea, confirming predictions based on island history. These results are further corroborated by mammae counts. Based on these lines of evidence, we include the Siberut population in T. chrysogaster and the Tanahbala population in T. ferruginea. Our conclusions expand the known distributions of both the Mentawai and Sumatran species. The larger geographical range of the endangered T. chrysogaster has conservation implications for this Mentawai endemic, so populations and habitat should be re-evaluated on each of the islands it inhabits. However, until such a re-evaluation is conducted, we recommend that the IUCN Red List status of this species be changed from ‘Endangered’ to ‘Data Deficient’.

  19. Rediscovery of Biswamoyopterus (Mammalia: Rodentia: Sciuridae: Pteromyini) in Asia, with the description of a new species from Lao PDR.

    PubMed

    Sanamxay, Daosavanh; Douangboubpha, Bounsavane; Bumrungsri, Sara; Xayavong, Sysouphanh; Xayaphet, Vilakhan; Satasook, Chutamas; Bates, Paul J J

    2013-01-01

    A new species of the flying squirrel genus Biswamoyopterus is described from Lao PDR. It is based on a single specimen collected from a local food market at Ban Thongnami, Pak Kading District, Bolikhamxai Province. The new taxon shows close affinities to Biswamoyopterus biswasi, which is only known from the holotype collected in 1981, 1250 km from the current locality, in Arunachal Pradesh, Northeast India. However, it differs substantially in pelage colour, most particularly on the ventral surfaces of the body, patagia, tail membrane, and tail. The single specimen was found in an area of central Lao PDR, which is characterised by its extensive limestone karst formations and which is home to other rare endemic rodents, including the Khanyou (Laonastes aenigmamus) nd the Lao limestone rat (Saxatilomyspaulinae). PMID:26473234

  20. A new microphallid (Digenea) species from Lontra provocax (Mammalia: Mustelidae) from freshwater environments of northwestern Patagonia (Argentina).

    PubMed

    Flores, Vernica R; Brugni, Norma L; Pozzi, Carla M

    2012-10-01

    A new microphallid species of Maritrema is described from the native southern river otter, Lontra provocax (Thomas). A naturally infected otter was found dead in the Nahuel Huapi National Park, Argentina. Ovigerous adult worms were recovered from the anterior portion of the intestine. Specimens of Maritrema huillini n. sp. have an unarmed genital pore and glabrous cirrus. They can be distinguished from all other species in the genus by having a long intestinal ceca extending up to three-quarters of the testes length to the level of the posterior border of the testes and a metraterm composed of a proximal sphincter, a non-muscular sac, and a distal muscular portion. This microphallid is the first species recovered from a South American eutherian host and the first digenean recorded for L. provocax. PMID:22540416

  1. Chewing through the Miocene: an examination of the feeding musculature in the ground sloth Hapalops from South America (Mammalia: Pilosa)

    PubMed Central

    Naples, Virginia L.; McAfee, Robert K.

    2014-01-01

    Hapalops, a smaller-sized and early sloth of the Megatheroidea, appeared in the middle Miocene Santa Cruz formation of Argentina. This genus is part of the group from which later, larger megatheroids arose, i.e., Nothrotheriops and Megatherium. Many cranial characters support this idea; however Hapalops is not merely a smaller antecedent of the later forms. Specifically, Hapalops retains short anterior caniniform teeth, and a temporomandibular joint elevated above the cheek tooth row; a combination distinct among sloths. An elevated temporomandibular joint occurs in Bradypus, a tree sloth with anterior chisel-shaped teeth instead of caniniforms, and the tree sloth Choloepus, which is aligned with the megalonychids, has anterior caniniforms. Hapalops has an elongated zygomatic ascending process that is reminiscent of that in Bradypus; however, the Bradypus skull is extremely foreshortened while that of Hapalops is elongated, as in nothrotheres, but not deepened as in megatheres. Previous work identified many sloth cranial character complexes, and functional limitations on skull feature combinations. The unique Hapalops character patterns indicate a selective feeder with a mediolaterally oriented grinding stroke during mastication. PMID:25075299

  2. Cranial and mandibular shape variation in the genus Carollia (Mammalia: Chiroptera) from Colombia: biogeographic patterns and morphological modularity

    PubMed Central

    Pérez-Torres, Jairo; Wilson, Laura A. B.

    2015-01-01

    Neotropical bats of the genus Carollia are widely studied due to their abundance, distribution and relevance for ecosystems. However, the ecomorphological boundaries of these species are poorly differentiated, and consequently correspondence between their geographic distribution, ecological plasticity and morphological variation remains unclear. In this study, patterns of cranial and mandibular morphological variation were assessed for Carollia brevicauda, C. castanea and C. perspicillata from Colombia. Using geometric morphometrics, morphological variation was examined with respect to: differences in intraspecific variation, morphological modularity and integration, and biogeographic patterns. Patterns of intraspecific variation were different for each species in both cranial and mandibular morphology, with functional differences apparent according to diet. Cranial modularity varied between species whereas mandibular modularity did not. High cranial and mandibular correlation reflects Cranium-Mandible integration as a functional unit. Similarity between the biogeographic patterns in C. brevicauda and C. perspicillata indicates that the Andes do not act as a barrier but rather as an independent region, isolating the morphology of Andean populations of larger-bodied species. The biogeographic pattern for C. castanea was not associated with the physiography of the Andes, suggesting that large body size does not benefit C. brevicauda and C. perspicillata in maintaining homogeneous morphologies among populations. PMID:26413433

  3. The sweet spot of a biological hammer: the centre of percussion of glyptodont (Mammalia: Xenarthra) tail clubs

    PubMed Central

    Blanco, R. Ernesto; Jones, Washington W.; Rinderknecht, Andrés

    2009-01-01

    The importance of the centre of percussion (CP) of some hand-held sporting equipment (such as tennis rackets and baseball bats) for athletic performance is well known. In order to avoid injuries it is important that powerful blows are located close to the CP. Several species of glyptodont (giant armoured mammals) had tail clubs that can be modelled as rigid beams (like baseball bats) and it is generally assumed that these were useful for agonistic behaviour. However, the variation in tail club morphology among known genera suggests that a biomechanical and functional analysis of these structures could be useful. Here, we outline a novel method to determine the CP of the glyptodont tail clubs. We find that the largest species had the CP very close to the possible location of horny spikes. This is consistent with the inference that they were adapted to delivering powerful blows at that point. Our new analysis reinforces the case for agonistic use of tail clubs in several glyptodont species. PMID:19710060

  4. [Decorative forms of hamsters Phodopus (Mammalia, Cricetinae): an analysis of genetic lines distribution and peculiarities of hair changes].

    PubMed

    Feoktistova, N Iu; Chernova, O F; Meshcherski?, I G

    2012-01-01

    Three species of dwarf hamsters (genus Phodopus, family Cricetidae) inhabit some regions of Russia, Kazakhstan, Mongolia, and China, each having quite extensive range. In recent decades, the dwarf hamsters became widely spread all over the world, initially as laboratory animals and later as popular pets. By now, there is lot of decorative breed lines and colored forms of these animals. Comparison of mtDNA nucleotide sequences of dwarf hamsters acquired in pet shops of some countries in Europe, South-East Asia and North America with distribution of mtDNA haplotypes within natural ranges showed the limitation of decorative line founders' points of origin by one region for each of the species. All haplotypes found in decorative Dzungarian hamsters (Ph. sungorus) purchased ounside Russia coincide with or are significantly close to haplotypes spread in the southern part of West Siberia (Russia) and adjacent regions of Kazakhstan; haplotypes of decorative Campbell's hamster (Ph. campbelli) belong to haplogroup of this species natural populations inhabiting South Tyva (Russia); and all studied decorative Desert hamsters (Ph. roborovskii) had one hapotype specific for South-Eastern Kazakhstan. The review of the history of researches on dwarf hamsters biology allows to determine delivery of hamsters from mentioned regions to scientific laboratories and zoos by certain expeditions and/or researchers. Unlike hamsters with natural hair color, the colored hamsters have no normal hair. Their hair is dull and straggly. The hair differentiation (presence of different hair types and their size characteristics) gets broken and results in deformation, bending, and splitting of the shaft, cracks in cuticle, change of configuration and location of medulla, uneven development of cortex. It is assumed that these destructive changes are associated with genetic characteristics of these hamsters' colored forms. PMID:22590908

  5. Novel gene conversion between X-Y homologues located in the nonrecombining region of the Y chromosome in Felidae (Mammalia)

    PubMed Central

    Pecon Slattery, Jill; Sanner-Wachter, Leslie; O'Brien, Stephen J.

    2000-01-01

    Genes located on the mammalian Y chromosome outside of the pseudoautosomal region do not recombine with those on the X and are predicted to either undergo selection for male function or gradually degenerate because of an accumulation of deleterious mutations. Here, phylogenetic analyses of X-Y homologues, Zfx and Zfy, among 26 felid species indicate two ancestral episodes of directed genetic exchange (ectopic gene conversion) from X to Y: once during the evolution of pallas cat and once in a common predecessor of ocelot lineage species. Replacement of the more rapidly evolving Y homologue with the evolutionarily constrained X copy may represent a mechanism for adaptive editing of functional genes on the nonrecombining region of the mammalian Y chromosome. PMID:10805789

  6. A Systematic Study on Tooth Enamel Microstructures of Lambdopsalis bulla (Multituberculate, Mammalia) - Implications for Multituberculate Biology and Phylogeny

    PubMed Central

    Mao, Fangyuan; Wang, Yuanqing; Meng, Jin

    2015-01-01

    Tooth enamel microstructure is a reliable and widely used indicator of dietary interpretations and data for phylogenetic reconstruction, if all levels of variability are investigated. It is usually difficult to have a thorough examination at all levels of enamel structures for any mammals, especially for the early mammals, which are commonly represented by sparse specimens. Because of the random preservation of specimens, enamel microstructures from different teeth in various species are often compared. There are few examples that convincingly show intraspecific variation of tooth enamel microstructure in full dentition of a species, including multituberculates. Here we present a systematic survey of tooth enamel microstructures of Lambdopsalis bulla, a taeniolabidoid multituberculate from the Late Paleocene Nomogen Formation, Inner Mongolia. We examined enamel structures at all hierarchical levels. The samples are treated differently in section orientations and acid preparation and examined using different imaging methods. The results show that, except for preparation artifacts, the crystallites, enamel types, Schmelzmuster and dentition types of Lambdopsalis are relatively consistent in all permanent teeth, but the prism type, including the prism shape, size and density, may vary in different portions of a single tooth or among different teeth of an individual animal. The most common Schmelzmuster of the permanent teeth in Lambdopsalis is a combination of radial enamel in the inner and middle layers, aprismatic enamel in the outer layer, and irregular decussations in tooth crown area with great curvature. The prism seam is another comparably stable characteristic that may be a useful feature for multituberculate taxonomy. The systematic documentation of enamel structures in Lambdopsalis may be generalized for the enamel microstructure study, and thus for taxonomy and phylogenetic reconstruction, of multituberculates and even informative for the enamel study of other early mammals. PMID:26020958

  7. A new species of nectar-feeding bat, genus Lonchophylla, from western Colombia and western Ecuador (Mammalia: Chiroptera: Phyllostomidae)

    USGS Publications Warehouse

    Woodman, N.

    2007-01-01

    The twelve recognized species of nectar-feeding bats of the genus Lonchophylla occur in low- and middle-elevation, humid, Neotropical forests. Morphological and morphometrical analyses of specimens formerly lumped with Lonchophylla mordax O. Thomas (1903) support recognition of Lonchophylla concava Goldman (1914) as a separate species and reveal a third species from the western Pacific lowlands of Colombia and Ecuador that I describe herein as Lonchophylla jornicata. This new species is morphologically similar to Lonchophylla concava but is distinctively larger than that species. Tests for sexual dimorphism within these and other species of Lonchophyllini suggest a tendency for females to have slightly longer, narrower skulls, higher coronoid processes of the mandible, and longer forearms than males.

  8. The Effects of Feeding Unpredictability and Classical Conditioning on Pre-Release Training of White-Lipped Peccary (Mammalia, Tayassuidae)

    PubMed Central

    Nogueira, Selene S. C.; Abreu, Shauana A.; Peregrino, Helderes; Nogueira-Filho, Srgio L. G.

    2014-01-01

    Some authors have suggested that environmental unpredictability, accompanied by some sort of signal for behavioral conditioning, can boost activity or foster exploratory behavior, which may increase post-release success in re-introduction programs. Thus, using white-lipped peccary (Tayassu pecari), a vulnerable Neotropical species, as a model, we evaluated an unpredictable feeding schedule. Associating this with the effect of classical conditioning on behavioral activities, we assessed the inclusion of this approach in pre-release training protocols. The experimental design comprised predictable feeding phases (control phases: C1, C2 and C3) and unpredictable feeding phases (U1- signaled and U2- non-signaled). The animals explored more during the signaled and non-signaled unpredictable phases and during the second control phase (C2) than during the other two predictable phases (C1 and C3). The peccaries also spent less time feeding during the signaled unpredictable phase (U1) and the following control phase (C2) than during the other phases. Moreover, they spent more time in aggressive encounters during U1 than the other experimental phases. However, the animals did not show differences in the time they spent on affiliative interactions or in the body weight change during the different phases. The signaled unpredictability, besides improving foraging behavior, showing a prolonged effect on the next control phase (C2), also increased the competition for food. The signaled feeding unpredictability schedule, mimicking wild conditions by eliciting the expression of naturalistic behaviors in pre-release training, may be essential to fully prepare them for survival in the wild. PMID:24475072

  9. Taxonomic status and paleoecology of Rusingoryx atopocranion (Mammalia, Artiodactyla), an extinct Pleistocene bovid from Rusinga Island, Kenya

    NASA Astrophysics Data System (ADS)

    Faith, J. Tyler; Choiniere, Jonah N.; Tryon, Christian A.; Peppe, Daniel J.; Fox, David L.

    2011-05-01

    Rusingoryx atopocranion is a poorly known extinct alcelaphine bovid, documented in Pleistocene deposits associated with Middle Stone Age artifacts on Rusinga Island, Kenya. Following its initial description, Rusingoryx was subsumed into Megalotragus, which includes the extinct giant wildebeests, on the basis of its cranial architecture. Renewed investigations of the Pleistocene deposits on Rusinga Island recovered a large sample of Rusingoryx specimens that provide new taxonomic and paleoecological insight. This study (1) reviews the morphological and phylogenetic evidence concerning the taxonomic status of Rusingoryx and (2) evaluates its paleoecology and dietary habits . The morphology and phylogenetic data indicate that Rusingoryx is distinct from Megalotragus; they likely shared a common ancestor in the late Pliocene. Ecomorphology and mesowear analysis point to a specialized grazing adaptation, and its association with arid-adapted ungulates suggests a preference for arid grasslands. The confirmation of Rusingoryx as a valid taxonomic entity, together with the presence of other extinct taxa (including Megalotragus) on Rusinga Island, suggests an increasingly complex pattern of ungulate biogeography and extinctions in the late Quaternary of East Africa. Rusingoryx appears to have been part of an arid-adapted faunal community that potentially persisted in East Africa until the onset of the Holocene.

  10. The occurrence of bothriodontines (Artiodactyla, Mammalia) in the Paleogene of Asia with special reference to Elomeryx: Paleobiogeographical implications

    NASA Astrophysics Data System (ADS)

    Ducrocq, S.; Lihoreau, F.

    2006-10-01

    Anthracotheriid remains from several Paleogene localities of central and eastern Asia have been re-examined. Several fossil remains attributed to the genera Bothriodon, Brachyodus and Hyoboops can be referred to Elomeryx which extends the geographical distribution of the genus to the whole area of Asia. These results demonstrate the role that Asia played in the biogeographical history of mammals and further support the proposed origin of North American Elomeryx from an Asian ancestor.

  11. First discovery of Helohyidae (Artiodactyla, Mammalia) in the Late Eocene of Thailand: a possible transitional form for Anthracotheriidae

    NASA Astrophysics Data System (ADS)

    Ducrocq, Stéphane; Chaimanee, Yaowalak; Suteethorn, Varavudh; Jaeger, Jean-Jacques

    1997-09-01

    Dental remains of the earliest known helohyid artiodactyl are described from the Late Eocene of Krabi in South Thailand. This new form, Progenitohyus thailandicus n.g. n.sp., is distinct from Gobiohyus, a specialized genus from the Middle Eocene of Mongolia, and it displays strong affinities with the primitive anthracotheriid Siamotherium krabiense from Krabi. Both Thai species certainly testify to an ancestor-descendant relationship, but an even earlier differentiation of Helohyidae and Anthracotheriidae should be searched for in the Middle Eocene or even earlier.

  12. A Peculiar New Pampatheriidae (Mammalia: Xenarthra: Cingulata) from the Pleistocene of Argentina and Comments on Pampatheriidae Diversity

    PubMed Central

    Scillato-Yané, Gustavo Juan; Soibelzon, Esteban

    2015-01-01

    Pampatheriidae are a group of cingulates native to South American that are known from the middle Miocene to the lower Holocene. Two genera have been recognized between the lower Pleistocene and the lower Holocene: Pampatherium Gervais and Ameghino (Ensenadan, Bonaerian and Lujanian, lower Pleistocene–lower Holocene) and Holmesina Simpson (Blancan, Irvingtonian, upper Pliocene–lower Holocene). They have been mainly differentiated by their osteoderm morphology and cranio-dental characters. These taxa had a wide latitudinal distribution, extending from the southern part of South America (Península Valdés, Argentina) to North America (Florida, USA). In this contribution, we describe a new genus and species of Pampatheriidae for the lower and middle Pleistocene of Buenos Aires Province and for the upper Pleistocene of Santa Fe Province (Argentina).The new taxon is represented by disarticulated osteoderms, one skull element, two thoracic vertebrae and a right femur and patella. It has extremely complex osteoderm ornamentations and particular morphological characters of the cranial element and femur that are not found in any other species of the family. This new taxon, recorded in the lower–middle Pleistocene (Ensenadan Stage/Age) and in the upper Pleistocene–early Holocene (Lujanian Stage/Age), is incorporated to the Pleistocene mammal assemblage of South America. Finally, the Pampatheriidae diversity is greater during the Lujanian Stage/Age than the Ensenadan Stage/Age. PMID:26083486

  13. The Adaptive Significance of Enamel Loss in the Mandibular Incisors of Cercopithecine Primates (Mammalia: Cercopithecidae): A Finite Element Modelling Study

    PubMed Central

    Kupczik, Kornelius; Lev-Tov Chattah, Netta

    2014-01-01

    In several primate groups enamel is reduced or absent from the lingual (tongue) side of the mandibular incisor crowns akin to other placental and marsupial mammalian groups such as rodents, lagomorphs and wombats. Here we investigate the presumed adaptation of crowns with unilateral enamel to the incision of tough foods in cercopithecines, an Old World monkey subfamily, using a simulation approach. We developed and validated a finite element model of the lower central incisor of the rhesus macaque (Macaca mulatta) with labial enamel only to compute three-dimensional displacements and maximum principal stresses on the crown subjected to compressive loads varying in orientation. Moreover, we developed a model of a macaque incisor with enamel present on both labial and lingual aspects, thus resembling the ancestral condition found in the sister taxon, the leaf-eating colobines. The results showed that, concomitant with experimental results, the cercopithecine crown with unilateral enamel bends predominantly towards the inside of the mouth, while displacements decreased when both labial and lingual enamel are present. Importantly, the cercopithecine incisor crown experienced lower maximum principal stress on the lingual side compared to the incisor with enamel on the lingual and labial aspects under non-axial loads directed either towards the inside or outside of the mouth. These findings suggest that cercopithecine mandibular incisors are adapted to a wide range of ingestive behaviours compared to colobines. We conclude that the evolutionary loss of lingual enamel in cercopithecines has conferred a safeguard against crown failure under a loading regime assumed for the ingestion (peeling, scraping) of tough-skinned fruits. PMID:24831704

  14. Mammals from ‘down under’: a multi-gene species-level phylogeny of marsupial mammals (Mammalia, Metatheria)

    PubMed Central

    Kilpatrick, C. William; Agnarsson, Ingi

    2015-01-01

    Marsupials or metatherians are a group of mammals that are distinct in giving birth to young at early stages of development and in having a prolonged investment in lactation. The group consists of nearly 350 extant species, including kangaroos, koala, possums, and their relatives. Marsupials are an old lineage thought to have diverged from early therian mammals some 160 million years ago in the Jurassic, and have a remarkable evolutionary and biogeographical history, with extant species restricted to the Americas, mostly South America, and to Australasia. Although the group has been the subject of decades of phylogenetic research, the marsupial tree of life remains controversial, with most studies focusing on only a fraction of the species diversity within the infraclass. Here we present the first Methaterian species-level phylogeny to include 80% of the extant marsupial species and five nuclear and five mitochondrial markers obtained from Genbank and a recently published retroposon matrix. Our primary goal is to provide a summary phylogeny that will serve as a tool for comparative research. We evaluate the extent to which the phylogeny recovers current phylogenetic knowledge based on the recovery of “benchmark clades” from prior studies—unambiguously supported key clades and undisputed traditional taxonomic groups. The Bayesian phylogenetic analyses recovered nearly all benchmark clades but failed to find support for the suborder Phalagiformes. The most significant difference with previous published topologies is the support for Australidelphia as a group containing Microbiotheriidae, nested within American marsupials. However, a likelihood ratio test shows that alternative topologies with monophyletic Australidelphia and Ameridelphia are not significantly different than the preferred tree. Although further data are needed to solidify understanding of Methateria phylogeny, the new phylogenetic hypothesis provided here offers a well resolved and detailed tool for comparative analyses, covering the majority of the known species richness of the group. PMID:25755933

  15. The clavicles of Smilodon fatalis and Panthera atrox (Mammalia: Felidae) from Rancho La Brea, Los Angeles, California.

    PubMed

    Hartstone-Rose, Adam; Long, Ryan C; Farrell, Aisling B; Shaw, Christopher A

    2012-09-01

    The Rancho La Brea collections at the George C. Page Museum in Los Angeles, California, contain the largest single inventory of Smilodon fatalis remains representing virtually every bone in the skeleton. Eighteen clavicles of two distinctive shapes have been recovered from historical and recent excavations at Rancho La Brea. In this study, we identify these specimens to species through comparison of their morphology and morphological variability with clavicles found in modern felids. This study includes a reevaluation of clavicles that have been previously assigned to S. fatalis, which are more likely to be those of Panthera atrox, and the description of pantherine cat clavicles. A previously undescribed sample of clavicles not only includes some of the same pantherine morph but also 10 specimens, herein assigned to S. fatalis, which are morphologically distinctive and significantly smaller than the previously described specimens. In addition, we report unexpected variations between clavicles of Panthera leo and P. tigris: the clavicles of P. leo closely resemble those of the large Rancho La Brea clavicle morph-which presumably belongs to P. atrox-thus supporting a P. leo/P. atrox clade. We report distinctive morphology of the clavicles of Acinonyx jubatus. Possible functional and phylogenic significance of felid clavicles is suggested. PMID:22592918

  16. Hares on ice: phylogeography and historical demographics of Lepus arcticus, L. othus, and L. timidus (Mammalia: Lagomorpha).

    PubMed

    Waltari, Eric; Cook, Joseph A

    2005-09-01

    Phylogeographical investigations of arctic organisms provide spatial and temporal frameworks for interpreting the role of climate change on biotic diversity in high-latitude ecosystems. Phylogenetic analyses were conducted on 473 base pairs of the mitochondrial control region in 192 arctic hares (Lepus arcticus, Lepus othus, Lepus timidus) and two individual Lepus townsendii. The three arctic hare species are closely related. All L. othus individuals form one well-supported clade, L. arcticus individuals form two well-supported clades, and L. timidus individuals are scattered throughout the phylogeny. Arctic hare distribution was altered dramatically following post-Pleistocene recession of continental ice sheets. We tested for genetic signatures of population expansion for hare populations now found in deglaciated areas. Historical demographic estimates for 12 arctic hare populations from throughout their range indicate that L. arcticus and L. othus persisted in two separate North American arctic refugia (Beringia and High Canadian Arctic) during glacial advances of the Pleistocene, while the high genetic diversity in L. timidus likely reflects multiple Eurasian refugia. PMID:16101770

  17. The northernmost record of Catagonus stenocephalus (Lund in Reinhardt, 1880) (Mammalia, Cetartiodactyla) and its palaeoenvironmental and palaeobiogeographical significance

    NASA Astrophysics Data System (ADS)

    Avilla, Leonardo S.; Mller, Lisiane; Gasparini, German M.; Soibelzon, Leopoldo; Absolon, Bruno; Pgo, Frederico Bonissoni; Silva, Rafael C.; Kinoshita, Angela; Graciano Figueiredo, Ana Maria; Baffa, Oswaldo

    2013-03-01

    During fieldwork carried out in January 2009 at Aurora do Tocantins (Tocantins State, northern Brazil), we recovered a fragmentary right maxilla (UNIRIO-PM 1006) of Catagonus stenocephalus from a sedimentary deposit of presumed late Pleistocene age in a karstic cave. This paper aims to: (1) provide the first record of C. stenocephalus in the northern region of Brazil (and consequently, also the northernmost one); (2) update the geographic distribution of C. stenocephalus; (3) present a date for the specimen; and (4) discuss the palaeoenvironmental and palaeobiogeographical implications of the finding. The species C. stenocephalus (Lund) is known from the Bonaerian (middle Pleistocene) and Lujanian (late Pleistocene to earliest Holocene) ages in Argentina, Uruguay, Brazil and Bolivia. The new record presented here extends the geographical distribution of C. stenocephalus more than 1000 km north from the former northernmost record (caves of Lagoa Santa region). Peccaries of the genus Catagonus have several morphological features associated with cursorial habits in relatively open and dry environments. The new distributional range of C. stenocephalus is coincident with the Chacoan subregion, characterized by dry climates and open areas. As the studied material comes from the top of the carbonate layer, this may suggest that the deposition of the C. stenocephalus remains described here is synchronous with the onset of a wetter climate phase. This argument is also in accordance with the datation results, around 20 ky BP, just after the last glacial maximum. This increasingly wet climate, which may also be related to the climatic changes that occurred during the late Pleistocene/early Holocene, could be a factor in the extinction of C. stenocephalus in South America.

  18. Didelphidae marsupials (Mammalia, Didelphimorphia) from the late Pleistocene deposit of the Gruta dos Moura Cave, northern Brazil.

    PubMed

    Nova, Patricia Villa; Avilla, Leonardo S; Oliveira, Édison V

    2015-03-01

    The present study acknowledges the diversity of fossil marsupials from the Gruta dos Moura cave, as well as environmental and climatic aspects during the Quaternary. The results show that this is the largest diversity of Pleistocene marsupials recorded in a single cave: Didelphis albiventris, D. aurita, Gracilinanus agilis, G. microtarsus, Marmosa murina, Monodelphis brevicaudata, M. domestica and Sairadelphys tocantinensis. Furthermore, the described specimens are also part of the only fossil assemblage unequivocally referable to the late Pleistocene. Paleontological studies suggest an intimate association with dry and open environments with high abundance of water sources. Since most of the identified taxa are characteristic of open forests and gallery forests, this could represent the actual environment around the Gruta dos Moura cave. Recent studies identified sympatric occurrences between species from open and dry environments and species from humid forests that were identified among our material and are characteristic of humid regions. Therefore, these species could inhabit gallery forests and capons, or even ecotones, inside a dry and open environment. Moreover, the extinction of Sairadelphys could also indicate that the climatic and environmental conditions changed or that the past environment was more heterogeneous than the current environment of the region. PMID:25806985

  19. A Systematic Study on Tooth Enamel Microstructures of Lambdopsalis bulla (Multituberculate, Mammalia)--Implications for Multituberculate Biology and Phylogeny.

    PubMed

    Mao, Fangyuan; Wang, Yuanqing; Meng, Jin

    2015-01-01

    Tooth enamel microstructure is a reliable and widely used indicator of dietary interpretations and data for phylogenetic reconstruction, if all levels of variability are investigated. It is usually difficult to have a thorough examination at all levels of enamel structures for any mammals, especially for the early mammals, which are commonly represented by sparse specimens. Because of the random preservation of specimens, enamel microstructures from different teeth in various species are often compared. There are few examples that convincingly show intraspecific variation of tooth enamel microstructure in full dentition of a species, including multituberculates. Here we present a systematic survey of tooth enamel microstructures of Lambdopsalis bulla, a taeniolabidoid multituberculate from the Late Paleocene Nomogen Formation, Inner Mongolia. We examined enamel structures at all hierarchical levels. The samples are treated differently in section orientations and acid preparation and examined using different imaging methods. The results show that, except for preparation artifacts, the crystallites, enamel types, Schmelzmuster and dentition types of Lambdopsalis are relatively consistent in all permanent teeth, but the prism type, including the prism shape, size and density, may vary in different portions of a single tooth or among different teeth of an individual animal. The most common Schmelzmuster of the permanent teeth in Lambdopsalis is a combination of radial enamel in the inner and middle layers, aprismatic enamel in the outer layer, and irregular decussations in tooth crown area with great curvature. The prism seam is another comparably stable characteristic that may be a useful feature for multituberculate taxonomy. The systematic documentation of enamel structures in Lambdopsalis may be generalized for the enamel microstructure study, and thus for taxonomy and phylogenetic reconstruction, of multituberculates and even informative for the enamel study of other early mammals. PMID:26020958

  20. Diet and habitat of toxodont megaherbivores (Mammalia, Notoungulata) from the late Quaternary of South and Central America

    NASA Astrophysics Data System (ADS)

    MacFadden, Bruce J.

    2005-09-01

    The toxodont megaherbivores Toxodon and Mixotoxodon were endemic to South and Central America during the late Quaternary. Isotopic signatures of 47 toxodont teeth were analyzed to reconstruct diet and ancient habitat. Tooth enamel carbon isotope data from six regions of South and Central America indicate significant differences in toxodont diet and local vegetation during the late Quaternary. Toxodonts ranged ecologically from C 3 forest browsers in the Amazon (mean ? 13C = -13.4), to mixed C 3 grazers and/or browsers living either in C 3 grasslands, or mixed C 3 forested and grassland habitats in Honduras (mean ? 13C = -9.3), Buenos Aires province, Argentina (? 13C = -8.7), and Bahia, Brazil (mean ? 13C = -8.6), to predominantly C 4 grazers in northern Argentina (? 13C = -4.4), to specialized C 4 grazers in the Chaco of Bolivia (? 13C = -0.1). Although these toxodonts had very high-crowned teeth classically interpreted for grazing, the isotopic data indicate that these megaherbivores had the evolutionary capacity to feed on a variety of dominant local vegetation. In the ancient Amazon region, carbon isotope data for the toxodonts indicate a C 3-based tropical rainforest habitat with no evidence for grasslands as would be predicted from the Neotropical forest refugia hypothesis.

  1. Mixed infection in the anteater Tamandua tetradactyla (Mammalia: Pilosa) from Par State, Brazil: Trypanosoma cruzi, T. rangeli and Leishmania infantum.

    PubMed

    De Arajo, Vitor Antnio L; Boit, Mariana C; Cupolillo, Elisa; Jansen, Ana Maria; Roque, Andr Luiz R

    2013-04-01

    Some Trypanosoma and Leishmania species are multi-host parasites whose distribution overlaps in several parts of the Brazilian Amazon basin. Despite being a common trait among wild mammals, mixed infections and their consequences for the host's health and parasite transmission are still a poorly known phenomenon. Here we describe a triple mixed infection - Trypanosoma cruzi, T. rangeli and Leishmania infantum - in a bone marrow sample from an anteater Tamandua tetradactyla captured in a house backyard from the endemic Abaetetuba municipality in the Amazon basin. T. cruzi was also isolated from blood samples. The mini-exon multiplex PCR characterization detected the infection by T. rangeli and T. cruzi (TcI genotype), while L. infantum infection was confirmed by an ITS-PCR followed by amplicon sequencing. This is the first description of T. rangeli isolation from bone marrow and the first report of L. infantum infection in xenarthrans. The implications of this finding are discussed considering the influence of mixed infections in the role of this mammal species as a putative reservoir host of these 3 trypanosomatid species. PMID:23253893

  2. Cranial Remain from Tunisia Provides New Clues for the Origin and Evolution of Sirenia (Mammalia, Afrotheria) in Africa

    PubMed Central

    Benoit, Julien; Adnet, Sylvain; El Mabrouk, Essid; Khayati, Hayet; Ben Haj Ali, Mustapha; Marivaux, Laurent; Merzeraud, Gilles; Merigeaud, Samuel; Vianey-Liaud, Monique; Tabuce, Rodolphe

    2013-01-01

    Sea cows (manatees, dugongs) are the only living marine mammals to feed solely on aquatic plants. Unlike whales or dolphins (Cetacea), the earliest evolutionary history of sirenians is poorly documented, and limited to a few fossils including skulls and skeletons of two genera composing the stem family of Prorastomidae (Prorastomus and Pezosiren). Surprisingly, these fossils come from the Eocene of Jamaica, while stem Hyracoidea and Proboscidea - the putative sister-groups to Sirenia - are recorded in Africa as early as the Late Paleocene. So far, the historical biogeography of early Sirenia has remained obscure given this paradox between phylogeny and fossil record. Here we use X-ray microtomography to investigate a newly discovered sirenian petrosal from the Eocene of Tunisia. This fossil represents the oldest occurrence of sirenians in Africa. The morphology of this petrosal is more primitive than the Jamaican prorastomids one, which emphasizes the basal position of this new African taxon within the Sirenia clade. This discovery testifies to the great antiquity of Sirenia in Africa, and therefore supports their African origin. While isotopic analyses previously suggested sirenians had adapted directly to the marine environment, new paleoenvironmental evidence suggests that basal-most sea cows were likely restricted to fresh waters. PMID:23342128

  3. Population structure of Lankatrematoides gardneri (Digenea: Opisthotrematidae) in the pancreas of the dugong (Dugong dugon) (Mammalia: Sirenia).

    PubMed

    Blair, D; Hudson, B E

    1992-12-01

    The distribution among size and reproductive classes of the digenean Lankatrematoides gardneri was recorded from the pancreatic ducts of 41 dugongs from the Gulf of Papua, Papua New Guinea. Infrapopulation sizes ranged from 5 to 921 worms and showed no correlation with host age, sex, or month of capture. Immature worms tended to be concentrated in intermediate size classes, the largest immatures being no more numerous than matures. The mean proportion of mature worms in the 29 infrapopulations containing them was small (9.8%). Mature worms were significantly greater in mass than the largest immatures. There is evidence of an interaction between the presence or absence of mature worms and the distribution of immatures among classes. PMID:1491302

  4. Shippingport, Kentucky, is the type locality for the white-footed mouse, Peromyscus leucopus (Rafinesque, 1818) (Mammalia: Rodentia: Cricetidae)

    USGS Publications Warehouse

    Woodman, Neal

    2015-01-01

    The white-footed mouse, Musculus leucopus Rafinesque, 1818 (= Peromyscus leucopus), is a common small mammal that is widespread in the eastern and central United States. Its abundance in many habitats renders it ecologically important, and its status as a reservoir for hantavirus and Lyme disease gives the species medical and economic significance. The recognition of two cytotypes and up to 17 morphological subspecies of P. leucopus indicates considerable variation in the species, and to understand this variation, it is important that the nominate subspecies be adequately defined so as to act as a standard for comparison. Relevant to this standard for the white-footed mouse is its type locality, which has generally been accepted to be either the vague "pine barrens of Kentucky" or the mouth of the Ohio River. Newly assembled information regarding the life and travels of Constantine S. Rafinesque, the North American naturalist who described P. leucopus, establishes that Rafinesque observed this species in July 1818 while visiting Shippingport, Kentucky, which is now within the city limits of Louisville, Jefferson Co., Kentucky. Shippingport is therefore the actual type locality for this species.

  5. A new form of the mole vole Ellobius tancrei Blasius, 1884 (Mammalia, Rodentia) with the lowest chromosome number.

    PubMed

    Bakloushinskaya, Irina; Romanenko, Svetlana A; Serdukova, Natalia A; Graphodatsky, Alexander S; Lyapunova, Elena A

    2013-01-01

    The subterranean mole vole, Ellobius tancrei, with aspecific variability in autosomes (2n = 31-54) and unusual sex chromosomes (XX in males and females), represents an amazing model for studying the role of chromosome changes in speciation. New materials from the upper reaches of the Surkhob River in the Pamiro-Alay mountains resulted in the discovery of a new form with 2n = 30. The application of Zoo-FISH and G-banding methods allowed the detection of 13 pairs of autosomes as Robertsonian metacentrics originated after fusions of acrocentrics of an assumed ancestral karyotype of Ellobius tancrei with 2n = 54. The sex chromosomes (XX, in both sexes) and one pair of acrocentric autosomes are the only acrocentrics in this karyotype, and the set with 2n = 30 possesses the lowest possible chromosome number among populations of Ellobius tancrei. PMID:24260698

  6. Cranial remain from Tunisia provides new clues for the origin and evolution of Sirenia (Mammalia, Afrotheria) in Africa.

    PubMed

    Benoit, Julien; Adnet, Sylvain; El Mabrouk, Essid; Khayati, Hayet; Ben Haj Ali, Mustapha; Marivaux, Laurent; Merzeraud, Gilles; Merigeaud, Samuel; Vianey-Liaud, Monique; Tabuce, Rodolphe

    2013-01-01

    Sea cows (manatees, dugongs) are the only living marine mammals to feed solely on aquatic plants. Unlike whales or dolphins (Cetacea), the earliest evolutionary history of sirenians is poorly documented, and limited to a few fossils including skulls and skeletons of two genera composing the stem family of Prorastomidae (Prorastomus and Pezosiren). Surprisingly, these fossils come from the Eocene of Jamaica, while stem Hyracoidea and Proboscidea--the putative sister-groups to Sirenia--are recorded in Africa as early as the Late Paleocene. So far, the historical biogeography of early Sirenia has remained obscure given this paradox between phylogeny and fossil record. Here we use X-ray microtomography to investigate a newly discovered sirenian petrosal from the Eocene of Tunisia. This fossil represents the oldest occurrence of sirenians in Africa. The morphology of this petrosal is more primitive than the Jamaican prorastomids' one, which emphasizes the basal position of this new African taxon within the Sirenia clade. This discovery testifies to the great antiquity of Sirenia in Africa, and therefore supports their African origin. While isotopic analyses previously suggested sirenians had adapted directly to the marine environment, new paleoenvironmental evidence suggests that basal-most sea cows were likely restricted to fresh waters. PMID:23342128

  7. Occurrence of the Indian genus Hemibos (Bovini, Bovidae, Mammalia) at the Early-Middle Pleistocene transition in Italy

    NASA Astrophysics Data System (ADS)

    Martnez-Navarro, Bienvenido; Palombo, Maria Rita

    2004-05-01

    The morphology of the horn-core structure and section shape of the Bos galerianus type specimen, as well as the general anatomy of the frontal and occipital areas of the skull, suggest that the skull is better attributed to the Indian genus Hemibos. This finding contributes to our understanding of faunal dispersal patterns into Europe at the Early-Middle Pleistocene transition.

  8. Case 3018. Cervus gouazoubira Fischer, 1814 (currently Mazama gouazoubira; Mammalia, Artiodactyla): proposed conservation as the correct original spelling

    USGS Publications Warehouse

    Gardner, A.L.

    1999-01-01

    The purpose of this application is to conserve the spelling of the specific name of Cervus gouazoubira Fischer, 1814 for the brown brocket deer of South America (family Cervidae). This spelling, rather than the original gouazoubira, has been in virtually universal usage for almost 50 years.

  9. A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids

    PubMed Central

    Tanaka, Yoshihiro; Kohno, Naoki

    2015-01-01

    The modern walrus, Odobenus rosmarus, is specialized and only extant member of the family Odobenidae. They were much more diversified in the past, and at least 16 genera and 20 species of fossil walruses have been known. Although their diversity increased in the late Miocene and Pliocene (around 8–2 Million years ago), older records are poorly known. A new genus and species of archaic odobenid, Archaeodobenus akamatsui, gen. et sp. nov. from the late Miocene (ca. 10.0–9.5 Ma) top of the Ichibangawa Formation, Hokkaido, northern Japan, suggests rapid diversification of basal Miocene walruses. Archaeodobenus akamatsui is the contemporaneous Pseudotaria muramotoi from the same formation, but they are distinguishable from each other in size and shape of the occipital condyle, foramen magnum and mastoid process of the cranium, and other postcranial features. Based on our phylogenetic analysis, A. akamatsui might have split from P. muramotoi at the late Miocene in the western North Pacific. This rapid diversification of the archaic odobenids occurred with a combination of marine regression and transgression, which provided geological isolation among the common ancestors of extinct odobenids. PMID:26244784

  10. Mammals from 'down under': a multi-gene species-level phylogeny of marsupial mammals (Mammalia, Metatheria).

    PubMed

    May-Collado, Laura J; Kilpatrick, C William; Agnarsson, Ingi

    2015-01-01

    Marsupials or metatherians are a group of mammals that are distinct in giving birth to young at early stages of development and in having a prolonged investment in lactation. The group consists of nearly 350 extant species, including kangaroos, koala, possums, and their relatives. Marsupials are an old lineage thought to have diverged from early therian mammals some 160 million years ago in the Jurassic, and have a remarkable evolutionary and biogeographical history, with extant species restricted to the Americas, mostly South America, and to Australasia. Although the group has been the subject of decades of phylogenetic research, the marsupial tree of life remains controversial, with most studies focusing on only a fraction of the species diversity within the infraclass. Here we present the first Methaterian species-level phylogeny to include 80% of the extant marsupial species and five nuclear and five mitochondrial markers obtained from Genbank and a recently published retroposon matrix. Our primary goal is to provide a summary phylogeny that will serve as a tool for comparative research. We evaluate the extent to which the phylogeny recovers current phylogenetic knowledge based on the recovery of "benchmark clades" from prior studies-unambiguously supported key clades and undisputed traditional taxonomic groups. The Bayesian phylogenetic analyses recovered nearly all benchmark clades but failed to find support for the suborder Phalagiformes. The most significant difference with previous published topologies is the support for Australidelphia as a group containing Microbiotheriidae, nested within American marsupials. However, a likelihood ratio test shows that alternative topologies with monophyletic Australidelphia and Ameridelphia are not significantly different than the preferred tree. Although further data are needed to solidify understanding of Methateria phylogeny, the new phylogenetic hypothesis provided here offers a well resolved and detailed tool for comparative analyses, covering the majority of the known species richness of the group. PMID:25755933

  11. New data on recently described rodent species Paulina's Limestone Rat Saxatilomys paulinae Musser, Smith, Robinson & Lunde, 2005 (Mammalia: Rodentia)

    PubMed Central

    Nguyen, Nghia Xuan; Ngo, Tuong Xuan; Nguyen, Duy Dinh

    2015-01-01

    Abstract Background Paulina's Limestone Rat Saxatilomys paulinae Musser et al., 2005 was first discovered by Musser et al. (2005) based on specimens from the Khammouane Limestone National Biodiversity Conservation Area (NBCA) in Khammouane Province in central Lao People's Democratic Republic (PDR). This tower karst landscape is part of the Central Indochina Limestone massif, which extends eastward into north-central Vietnam in Quang Binh and Quang Tri Provinces. New information In April 2014, we conducted a rodent survey and collected four (4) whole specimens of Saxatilomys paulinae in Quang Binh province. This is the first record of Saxatilomys paulinae in Vietnam. External and craniodental characteristics of all specimens clearly exhibit the characters of Saxatilomys paulinae as described in Musser et al. (2005)?. The rats are of medium size (HB: 160.3 2.03 mm, T: 192.3 6.69 mm) with some specific morpological characteristics. The external and craniodental measurement of the specimens from Vietnam tend to be larger than those of specimens from Lao. However, this needs to be verified by more studies in future. The habitat of Saxatilomys paulinae in Vietnam is characterized by complicated terrain comprising low karst towers (around 400 m) with steep slopes covered under limestone humid evergreen forest. The forest has been affected by selected timber logging in the past, but still has a complex 4-layer structure. The population of Saxatilomys paulinae in Vietnam is threatened by rodent trapping/snaring and habitat disturbance. More status surveys should be conducted to assess the species distributional range and its population status for undertaking relevant conservation measures. PMID:26023285

  12. Masticatory muscle architecture in the Laotian rock rat Laonastes aenigmamus (Mammalia, Rodentia): new insights into the evolution of hystricognathy

    PubMed Central

    Hautier, Lionel; Saksiri, Soonchan

    2009-01-01

    We present the first descriptive comparison of the skull, mandible and jaw muscles of the recently recovered Laotian rock rat Laonastes aenigmamus. The gross anatomy of five specimens captured in Laos and internal architecture of the jaw musculature were studied using dissections. The following muscles are described: temporal, masseter, pterygoids, digastric, mylohyoid, geniohyoid and transverse mandibular. The description of the masticatory apparatus of L. aenigmamus offers a rare opportunity to assess the order of establishment of the morphological characters during the evolution of Ctenohystrica. Striking convergences have occurred during the evolution of Diatomyidae and L. aenigmamus presents a unique combination of myological features that corresponds to a mixture of sciurognathous and hystricognathous characters. If L. aenigmamus is a sciurognathous rodent, we have to assume that it independently acquired a pars reflexa of the superficial masseter. We show for the first time that the development of this pars reflexa has occurred several times during the evolution of Ctenohystrica and can no longer be considered a synapomorphic feature of Hystricognathi. These results bring new insights into the evolution of hystricognathy and have profound implications for the interpretation of the fossil record of early hystricognath rodents. PMID:19694873

  13. Evolutionary and Biological Implications of Dental Mesial Drift in Rodents: The Case of the Ctenodactylidae (Rodentia, Mammalia)

    PubMed Central

    Gomes Rodrigues, Helder; Solé, Floréal; Charles, Cyril; Tafforeau, Paul; Vianey-Liaud, Monique; Viriot, Laurent

    2012-01-01

    Dental characters are importantly used for reconstructing the evolutionary history of mammals, because teeth represent the most abundant material available for the fossil species. However, the characteristics of dental renewal are presently poorly used, probably because dental formulae are frequently not properly established, whereas they could be of high interest for evolutionary and developmental issues. One of the oldest rodent families, the Ctenodactylidae, is intriguing in having longstanding disputed dental formulae. Here, we investigated 70 skulls among all extant ctenodactylid genera (Ctenodactylus, Felovia, Massoutiera and Pectinator) by using X-ray conventional and synchrotron microtomography in order to solve and discuss these dental issues. Our study clearly indicates that Massoutiera, Felovia and Ctenodactylus differ from Pectinator not only by a more derived dentition, but also by a more derived eruptive sequence. In addition to molars, their dentition only includes the fourth deciduous premolars, and no longer bears permanent premolars, conversely to Pectinator. Moreover, we found that these premolars are lost during adulthood, because of mesial drift of molars. Mesial drift is a striking mechanism involving migration of teeth allowed by both bone remodeling and dental resorption. This dental innovation is to date poorly known in rodents, since it is only the second report described. Interestingly, we noted that dental drift in rodents is always associated with high-crowned teeth favoring molar size enlargement. It can thus represent another adaptation to withstand high wear, inasmuch as these rodents inhabit desert environments where dust is abundant. A more accurate study of mesial drift in rodents would be very promising from evolutionary, biological and orthodontic points of view. PMID:23185576

  14. The complete mitochondrial genome of the Spotted Linsang, Prionodon pardicolor, the first representative from the family Prionodontidae (Mammalia, Carnivora).

    PubMed

    Hassanin, Alexandre; Veron, Géraldine

    2016-03-01

    The complete mitochondrial genome of the Spotted Linsang, Prionodon pardicolor, was sequenced using overlapping PCR products. The genome is 16,718 base pairs in length and contains the 37 genes found in a typical mammalian genome: 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The overall base composition on the L-strand is A: 32.4%, C: 25.0%, G: 13.9%, T: 28.7%. The control region of P. pardicolor includes both RS2 and RS3 tandem repeats. Phylogenetic analyses support a sister relationship with the Felidae. PMID:24937573

  15. The complete mitochondrial genome of the African palm civet, Nandinia binotata, the only representative of the family Nandiniidae (Mammalia, Carnivora).

    PubMed

    Hassanin, Alexandre

    2016-03-01

    Here I report the complete mitochondrial genome of the African palm civet, (Nandinia binotata) as sequenced from overlapping PCR products. The genome is 17,103 bp in length and contains the 37 genes found in a typical mammalian genome: 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The control region of N. binotata includes both RS2 and RS3 tandem repeats. The overall base composition on the L-strand is A: 33.6%, C: 27.3%, G: 13.0%, and T: 26.1%. PMID:24937569

  16. The complete mitochondrial genome of the Servaline Genet, Genetta servalina, the first representative from the family Viverridae (Mammalia, Carnivora).

    PubMed

    Hassanin, Alexandre

    2016-03-01

    Here I report the complete mitochondrial genome of the Servaline Genet, Genetta servalina, as sequenced from overlapping PCR products. The genome is 16,938 base pairs in length and contains the 37 genes found in a typical mammalian genome: 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The control region of G. servalina includes both RS2 and RS3 tandem repeats. The overall base composition on the L-strand is A: 32.8%, C: 25.5%, G: 13.5%, and T: 28.2%. PMID:24937571

  17. Nuclear DNA phylogeny of the squirrels (Mammalia: Rodentia) and the evolution of arboreality from c-myc and RAG1.

    PubMed

    Steppan, Scott J; Storz, Brian L; Hoffmann, Robert S

    2004-03-01

    Although the family Sciuridae is large and well known, phylogenetic analyses are scarce. We report on a comprehensive molecular phylogeny for the family. Two nuclear genes (c-myc and RAG1) comprising approximately 4500 bp of data (most in exons) are applied for the first time to rodent phylogenetics. Parsimony, likelihood, and Bayesian analyses of the separate gene regions and combined data reveal five major lineages and refute the conventional elevation of the flying squirrels (Pteromyinae) to subfamily status. Instead, flying squirrels are derived from one of the tree squirrel lineages. C-myc indels corroborate the sequence-based topologies. The common ancestor of extant squirrels appears to have been arboreal, confirming the fossil evidence. The results also reveal an unexpected clade of mostly terrestrial squirrels with African and Holarctic centers of diversity. We present a revised classification of squirrels. Our results demonstrate the phylogenetic utility of relatively slowly evolving nuclear exonic data even for relatively recent clades. PMID:15012949

  18. Sensitivity of populations of bats (Mammalia: Chiroptera) in relation to human development in northern Paran, southern Brazil.

    PubMed

    Reis, N R; Gallo, P H; Peracchi, A L; Lima, L P; Fregonezi, M N

    2012-08-01

    Most natural forests have been converted for human use, restricting biological life to small forest fragments. Many animals, including some species of bats are disappearing and the list of these species grows every day. It seems that the destruction of the habitat is one of its major causes. This study aimed to analyze how this community of bats was made up in environments with different sizes and quality of habitat. Data from studies conducted in the region of Londrina, Parana, Brazil, from 1982 to 2000 were used. Originally, this area was covered by a semi deciduous forest, especially Aspidosperma polyneuron (Apocynaceae), Ficus insipida (Moraceae), Euterpe edulis (Arecaceae), Croton floribundus (Euforbiaceae), and currently, only small remnants of the original vegetation still exist. The results showed a decline in the number of species caught in smaller areas compared to the largest remnant. In about 18 years of sampling, 42 species of bats were found in the region, representing 67% of the species that occur in Paran and 24.4% in Brazil. There were two species of Noctilionidae; 21 of Phyllostoma; 11 Vespertilionidae and eight Molossidae. Eight of these were captured only in the largest fragment, Mata dos Godoy State Park (680 ha). Ten species had a low capture rate in the smaller areas with less than three individuals. Of the total sampled, 14 species were found in human buildings, and were able to tolerate modified environments, foraging and even using them as shelter. As the size of the forest area increases, there is a greater variety of ecological opportunities and their physical conditions become more stable, i.e., conditions favorable for growth and survival of a greater number of species. Forest fragmentation limits and creates subpopulations, preserving only long-lived K-strategist animals for some time, where the supporting capacity of the environment is a limiting factor. The reduction of habitats, species and genetic diversity resulting from human activities are endangering the future adaptability in natural ecosystems, which promotes the disappearance of low adaptive potential species. PMID:22990822

  19. The highly specialized vocal tract of the male Mongolian gazelle (Procapra gutturosa Pallas, 1777 – Mammalia, Bovidae)

    PubMed Central

    Frey, R; Gebler, A

    2003-01-01

    The entire head and neck of a wild adult male Mongolian gazelle (Procapra gutturosa) was dissected with special reference to its enlarged larynx. Two additional adult male specimens taken from the wild were analysed by computer tomography. The sternomandibularis, omohyoideus, thyrohyoideus and hyoepiglotticus muscles are particularly enlarged and improve laryngeal suspension and stabilization. The epiglottis is exceptionally large. A permanent laryngeal descent is associated with the evolution of an unpaired palatinal pharyngeal pouch. A certain momentary descent seems to occur during vocalization. The high lateral walls of the thyroid cartilage are ventrally connected by a broad keel. The large thyroarytenoid muscle is divided into two portions: a rostral ventricularis and a caudal vocalis muscle. A paired lateral laryngeal ventricle projects between these two muscles. The massive vocal fold is large and lacks any rostrally directed flexible structures. It is supported by a large cymbal-like fibroelastic pad. Vocal tract length was measured in the course of dissection and in computer tomographic images. Two representative spectrograms, one of an adult male and one of a juvenile, recorded in the natural habitat of the Mongolian gazelle are presented. In the spectrograms, the centre frequency of the lowest band is about 500 Hz in the adult male and about 790 Hz in the juvenile. The low pitch of the adult male's call is ascribed to the evolutionary mass increase and elongation of the vocal folds. In the habitat of P. gutturosa a call with a low pitch and, thus, with an almost homogeneous directivity around the head of the vocalizing animal may be optimally suited for multidirectional advertisement calls during the rut. The signal range of an adult male's call in its natural habitat can therefore be expected to be larger than the high-pitched call of a juvenile. PMID:14635800

  20. Early Eocene rodents (Mammalia) from the Subathu Formation of type area (Himachal Pradesh), NW sub-Himalaya, India: Palaeobiogeographic implications

    NASA Astrophysics Data System (ADS)

    Gupta, Smita; Kumar, Kishor

    2015-08-01

    Based on isolated upper cheek teeth, two new early Eocene rodents (Subathumys solanorius gen. et sp. nov. and Subathumys globulus gen. et sp. nov.) and three others (Birbalomys cf. sondaari, Birbalomys sp., cf. Chapattimys sp.) are recorded from the lower-middle part of the Subathu Formation of the type area in Himachal Pradesh, northwestern sub-Himalaya (India). The new rodents exhibit morphological features most similar to the unified ctenodactyloid family Chapattimyidae (including Yuomyidae), which is also represented in the assemblage from the upper part (middle Eocene) of the Subathu Formation. The associated lower cheek teeth are provisionally described as three indeterminate chapattimyid taxa. The new Subathu rodents are somewhat younger than the previously documented early Eocene assemblages from the Indian subcontinent, and are chronologically intermediate between the early Eocene ailuravines from Gujarat in the western peninsular India and the middle Eocene chapattimyids from northwestern India and Pakistan. They suggest that chapattimyids originated in the sub-Himalayan region during the Ypresian, which is earlier than previously believed. The absence of ailuravines in this as well as younger rodent assemblages from the subcontinent seems to suggest that ailuravines (Ischyromyidae), within a relatively short time after their appearance in the peninsular India in the early Eocene, may have been replaced by the indigenous chapattimyids. The co-occurrence in the early Eocene Subathu assemblage of three or more chapattimyids indicates their early radiation and dominance during the early and middle Eocene. This record of rodents opens the possibility of recovery of other small mammal remains in older levels of the Subathu Formation, which will be important for understanding linkage with early Eocene faunas from peninsular India, Europe and North America.

  1. A New Late Miocene Odobenid (Mammalia: Carnivora) from Hokkaido, Japan Suggests Rapid Diversification of Basal Miocene Odobenids.

    PubMed

    Tanaka, Yoshihiro; Kohno, Naoki

    2015-01-01

    The modern walrus, Odobenus rosmarus, is specialized and only extant member of the family Odobenidae. They were much more diversified in the past, and at least 16 genera and 20 species of fossil walruses have been known. Although their diversity increased in the late Miocene and Pliocene (around 8-2 Million years ago), older records are poorly known. A new genus and species of archaic odobenid, Archaeodobenus akamatsui, gen. et sp. nov. from the late Miocene (ca. 10.0-9.5 Ma) top of the Ichibangawa Formation, Hokkaido, northern Japan, suggests rapid diversification of basal Miocene walruses. Archaeodobenus akamatsui is the contemporaneous Pseudotaria muramotoi from the same formation, but they are distinguishable from each other in size and shape of the occipital condyle, foramen magnum and mastoid process of the cranium, and other postcranial features. Based on our phylogenetic analysis, A. akamatsui might have split from P. muramotoi at the late Miocene in the western North Pacific. This rapid diversification of the archaic odobenids occurred with a combination of marine regression and transgression, which provided geological isolation among the common ancestors of extinct odobenids. PMID:26244784

  2. Post-glacial colonization of northwestern North America by the forest-associated American marten (Martes americana, Mammalia: Carnivora: Mustelidae).

    PubMed

    Stone, Karen D; Flynn, Rodney W; Cook, Joseph A

    2002-10-01

    Phylogeographic patterns were used to assess intraspecific diversification of American martens (Martes americana). Within martens, two morphological groups (americana and caurina) have been recognized, though the level of distinction between them has been debated. We examined mitochondrial cytochrome b gene haplotypes from 680 martens to explore the colonization history of the Pacific Northwest and found two clades that correspond to the morphological groups. The widespread americana clade extends from interior Alaska south to Montana and eastward to Newfoundland and New England (i.e. northwestern, north-central and northeastern North America). The caurina clade occurs in western North America, minimally extending from Admiralty Island (southeastern Alaska) south to Oregon and Wyoming. Our data indicated two colonization events for the Pacific Northwest (one by members of each clade) and were consistent with the persistence of populations throughout past glacial periods in eastern and western refugia. Due to vegetational and geological history following the past deglaciation, we hypothesize that martens of the caurina clade spread along the North Pacific Coast, and into southeastern Alaska, earlier than martens of the americana clade. Mismatch distributions for the americana clade were indicative of populations that recently experienced demographic expansion, while mismatch distributions for the caurina clade suggested that populations were at equilibrium. These clades are reciprocally monophyletic and distinctive (interclade divergence ranged from 2.5 to 3.0% (uncorrected p), whereas, intraclade divergence was < 0.7%), and two regions of sympatry have been identified. Genetic signatures of past admixture in hybrid zones may have been extinguished during subsequent glacial periods when ranges contracted. This recurrent pattern of relatively restricted western, or Pacific coastal, lineages and more widespread eastern, or interior continental, lineages exists across broad taxonomic groups and suggests a shared biogeographical history. PMID:12296948

  3. Trypanosoma cruzi Infection in Neotropical Wild Carnivores (Mammalia: Carnivora): At the Top of the T. cruzi Transmission Chain

    PubMed Central

    Rocha, Fabiana Lopes; Roque, Andr Luiz Rodrigues; de Lima, Juliane Saab; Cheida, Carolina Carvalho; Lemos, Frederico Gemesio; de Azevedo, Fernanda Cavalcanti; Arrais, Ricardo Corassa; Bilac, Daniele; Herrera, Heitor Miraglia; Mouro, Guilherme; Jansen, Ana Maria

    2013-01-01

    Little is known on the role played by Neotropical wild carnivores in the Trypanosoma cruzi transmission cycles. We investigated T. cruzi infection in wild carnivores from three sites in Brazil through parasitological and serological tests. The seven carnivore species examined were infected by T. cruzi, but high parasitemias detectable by hemoculture were found only in two Procyonidae species. Genotyping by Mini-exon gene, PCR-RFLP (1f8/Akw21I) and kDNA genomic targets revealed that the raccoon (Procyon cancrivorus) harbored TcI and the coatis (Nasua nasua) harbored TcI, TcII, TcIII-IV and Trypanosoma rangeli, in single and mixed infections, besides four T. cruzi isolates that displayed odd band patterns in the Mini-exon assay. These findings corroborate the coati can be a bioaccumulator of T. cruzi Discrete Typing Units (DTU) and may act as a transmission hub, a connection point joining sylvatic transmission cycles within terrestrial and arboreal mammals and vectors. Also, the odd band patterns observed in coatis isolates reinforce that T. cruzi diversity might be much higher than currently acknowledged. Additionally, we assembled our data with T. cruzi infection on Neotropical carnivores literature records to provide a comprehensive analysis of the infection patterns among distinct carnivore species, especially considering their ecological traits and phylogeny. Altogether, fifteen Neotropical carnivore species were found naturally infected by T. cruzi. Species diet was associated with T. cruzi infection rates, supporting the hypothesis that predator-prey links are important mechanisms for T. cruzi maintenance and dispersion in the wild. Distinct T. cruzi infection patterns across carnivore species and study sites were notable. Musteloidea species consistently exhibit high parasitemias in different studies which indicate their high infectivity potential. Mesocarnivores that feed on both invertebrates and mammals, including the coati, a host that can be bioaccumulator of T. cruzi DTUs, seem to take place at the top of the T. cruzi transmission chain. PMID:23861767

  4. First record of Mylagaulid rodents (Rodentia, Mammalia) from the Miocene of Eastern Siberia (Olkhon Island, Baikal Lake, Irkutsk Region, Russia).

    PubMed

    Tesakov, A S; Lopatin, A V

    2015-01-01

    A new genus and species of rodent, Lamugaulus olkhonensis, belonging to the subfamily Promylagaulinae of the family Mylagaulidae, is described on the basis of isolated teeth from the Khalagay Formation of the Lower Miocene Tagay locality (Olkhon island, Lake Baikal, Irkutsk Region). This is the first record of mylagaulids in Eastern Siberia, significantly expanding the data on the distribution of this mainly North American group of rodents in Asia and showing its presence outside the Central Asian arid zone. PMID:25773245

  5. Revision of the Wind River faunas, early Eocene of central Wyoming. IX - The oldest known hystricomorphous rodent (Mammalia: Rodentia)

    NASA Technical Reports Server (NTRS)

    Dawson, Mary R.; Krishtalka, Leonard; Stucky, Richard K.

    1990-01-01

    The rostral portion of the skull of a new genus and species of rodent, Armintomys tullbergi, from the earliest middle Eocene of the Wind River Basin (Wyoming) provides the geologically oldest known record of the hystricomorphous zygomasseteric structure. Armintomys also preserves the oldest known occurrence of incisor enamel that is transitional from pauciserial to uniserial. Other dental characters include: anteriorly grooved incisor, small premolars, and relatively primitive sciuravidlike molars. Analysis of this unique combination of characters implies that Armintomys is the oldest known myomorph rodent and the only known representative of a new family. Armintomyidae, which is referred, with question, to the myomorph superfamily Dipodoidea. Armintomys is more primitive, especially in premolar retention and structure, than the Bridgerian zapodid Elymys from Nevada, but adds to evidence from the latter for an early origin and radiation of dipodoid rodents.

  6. A Peculiar New Pampatheriidae (Mammalia: Xenarthra: Cingulata) from the Pleistocene of Argentina and Comments on Pampatheriidae Diversity.

    PubMed

    Gis, Flvio; Gonzlez Ruiz, Laureano Ral; Scillato-Yan, Gustavo Juan; Soibelzon, Esteban

    2015-01-01

    Pampatheriidae are a group of cingulates native to South American that are known from the middle Miocene to the lower Holocene. Two genera have been recognized between the lower Pleistocene and the lower Holocene: Pampatherium Gervais and Ameghino (Ensenadan, Bonaerian and Lujanian, lower Pleistocene-lower Holocene) and Holmesina Simpson (Blancan, Irvingtonian, upper Pliocene-lower Holocene). They have been mainly differentiated by their osteoderm morphology and cranio-dental characters. These taxa had a wide latitudinal distribution, extending from the southern part of South America (Pennsula Valds, Argentina) to North America (Florida, USA). In this contribution, we describe a new genus and species of Pampatheriidae for the lower and middle Pleistocene of Buenos Aires Province and for the upper Pleistocene of Santa Fe Province (Argentina).The new taxon is represented by disarticulated osteoderms, one skull element, two thoracic vertebrae and a right femur and patella. It has extremely complex osteoderm ornamentations and particular morphological characters of the cranial element and femur that are not found in any other species of the family. This new taxon, recorded in the lower-middle Pleistocene (Ensenadan Stage/Age) and in the upper Pleistocene-early Holocene (Lujanian Stage/Age), is incorporated to the Pleistocene mammal assemblage of South America. Finally, the Pampatheriidae diversity is greater during the Lujanian Stage/Age than the Ensenadan Stage/Age. PMID:26083486

  7. The adaptive significance of enamel loss in the mandibular incisors of cercopithecine primates (Mammalia: Cercopithecidae): a finite element modelling study.

    PubMed

    Kupczik, Kornelius; Lev-Tov Chattah, Netta

    2014-01-01

    In several primate groups enamel is reduced or absent from the lingual (tongue) side of the mandibular incisor crowns akin to other placental and marsupial mammalian groups such as rodents, lagomorphs and wombats. Here we investigate the presumed adaptation of crowns with unilateral enamel to the incision of tough foods in cercopithecines, an Old World monkey subfamily, using a simulation approach. We developed and validated a finite element model of the lower central incisor of the rhesus macaque (Macaca mulatta) with labial enamel only to compute three-dimensional displacements and maximum principal stresses on the crown subjected to compressive loads varying in orientation. Moreover, we developed a model of a macaque incisor with enamel present on both labial and lingual aspects, thus resembling the ancestral condition found in the sister taxon, the leaf-eating colobines. The results showed that, concomitant with experimental results, the cercopithecine crown with unilateral enamel bends predominantly towards the inside of the mouth, while displacements decreased when both labial and lingual enamel are present. Importantly, the cercopithecine incisor crown experienced lower maximum principal stress on the lingual side compared to the incisor with enamel on the lingual and labial aspects under non-axial loads directed either towards the inside or outside of the mouth. These findings suggest that cercopithecine mandibular incisors are adapted to a wide range of ingestive behaviours compared to colobines. We conclude that the evolutionary loss of lingual enamel in cercopithecines has conferred a safeguard against crown failure under a loading regime assumed for the ingestion (peeling, scraping) of tough-skinned fruits. PMID:24831704

  8. Homeotic Evolution in the Mammalia: Diversification of Therian Axial Seriation and the Morphogenetic Basis of Human Origins

    PubMed Central

    Filler, Aaron G.

    2007-01-01

    Background Despite the rising interest in homeotic genes, little has been known about the course and pattern of evolution of homeotic traits across the mammalian radiation. An array of emerging and diversifying homeotic gradients revealed by this study appear to generate new body plans and drive evolution at a large scale. Methodology/Principal Findings This study identifies and evaluates a set of homeotic gradients across 250 extant and fossil mammalian species and their antecedents over a period of 220 million years. These traits are generally expressed as co-linear gradients along the body axis rather than as distinct segmental identities. Relative position or occurrence sequence vary independently and are subject to polarity reversal and mirroring. Five major gradient modification sets are identified: (1)quantitative changes of primary segmental identity pattern that appeared at the origin of the tetrapods ; (2)frame shift relation of costal and vertebral identity which diversifies from the time of amniote origins; (3)duplication, mirroring, splitting and diversification of the neomorphic laminar process first commencing at the dawn of mammals; (4)emergence of homologically variable lumbar lateral processes upon commencement of the radiation of therian mammals and ; (5)inflexions and transpositions of the relative position of the horizontal septum of the body and the neuraxis at the emergence of various orders of therian mammals. Convergent functional changes under homeotic control include laminar articular engagement with septo-neural transposition and ventrally arrayed lumbar transverse process support systems. Conclusion/Significance Clusters of homeotic transformations mark the emergence point of mammals in the Triassic and the radiation of therians in the Cretaceous. A cluster of homeotic changes in the Miocene hominoid Morotopithecus that are still seen in humans supports establishment of a new hominiform clade and suggests a homeotic origin for the human upright body plan. PMID:17925867

  9. Expanded host diversity and geographic distribution of hantaviruses in sub-Saharan Africa.

    PubMed

    Kang, Hae Ji; Stanley, William T; Esselstyn, Jacob A; Gu, Se Hun; Yanagihara, Richard

    2014-07-01

    The recent discovery of hantaviruses in shrews and bats in West Africa suggests that other genetically distinct hantaviruses exist in East Africa. Genetic and phylogenetic analyses of newfound hantaviruses, detected in archival tissues from the Geata mouse shrew (Myosorex geata) and Kilimanjaro mouse shrew ( Myosorex zinki) captured in Tanzania, expands the host diversity and geographic distribution of hantaviruses and suggests that ancestral shrews and/or bats may have served as the original mammalian hosts of primordial hantaviruses. PMID:24741077

  10. Evaluation of the anti-emetic potential of anti-migraine drugs to prevent resiniferatoxin-induced emesis in Suncus murinus (house musk shrew).

    PubMed

    Cheng, Frankie H M; Andrews, Paul L R; Moreaux, Benoit; Ngan, Man-P; Rudd, John A; Sam, Tasia S W; Wai, Man-K; Wan, Christina

    2005-01-31

    Activation of vanilloid receptors has commonly been used to facilitate neurogenic inflammation and plasma exudation to model components of the pathogenesis of migraine; however, these studies have been performed mainly in species lacking the emetic reflex. In the present studies, therefore, we used Suncus murinus, a species of insectivore capable of emesis, to investigate if the vanilloid receptor agonist resiniferatoxin is capable of modeling the emesis associated with migraine. Resiniferatoxin (100 nmol/kg, s.c.) induced an emetic response that was antagonized significantly (P<0.05) by ruthenium red (1-3 micromol), (2R-trans)-4-[1-[3,5-bis(trifluromethyl)benzoyl]-2-(phenylmethyl)-4-piperidinyl]-N-(2,6-dimethylphenyl)-1-acetamide (S)-hydroxybutanedioate (R116301; 10-100 micromol/kg), and scopolamine (1 micromol/kg), but not by dihydroergotamine (0.3-3 micromol/kg), sumatriptan (1-10 micromol/kg), methysergide (1-10 micromol/kg), tropanyl 3,5-dichlorobenzoate (MDL72222; 3-30 micromol/kg), ondansetron (0.3-3 micromol/kg), metoclopramide (3-30 micromol/kg), domperidone (3-30 micromol/kg), diphenhydramine (1-10 micromol/kg), or indomethacin (3-30 micromol/kg). The failure of a wide range of representative anti-migraine drugs to reduce retching and vomiting limits the use of this model to identify/investigate novel treatments for the emesis (and nausea) associated with migraine attacks in humans. However, the results provide further evidence for the involvement of a novel vanilloid receptor in resiniferatoxin-induced emesis and implicate both tachykinins and acetylcholine in the pathway(s) activated by resiniferatoxin in S. murinus. PMID:15680276

  11. Placental diversity in malagasy tenrecs: placentation in shrew tenrecs (Microgale spp.), the mole-like rice tenrec (Oryzorictes hova) and the web-footed tenrec (Limnogale mergulus).

    PubMed

    Enders, A C; Blankenship, T N; Goodman, S M; Soarimalala, V; Carter, A M

    2007-07-01

    Placentation in tenrecs of the subfamily Oryzorictinae, family Tenrecidae, has not been described previously. The structure of the placenta of this group and especially of the genus Microgale was investigated to determine its similarity or dissimilarity to previously described placentas of the tenrec subfamilies Potamogalinae and Tenrecinae. Fifteen specimens of the genus Microgale ranging from an early yolk sac stage to near term were available for study. Placentation in Microgale was found to be different from other tenrecids in that there is an early simple lateral rather than central haemophagous region. In addition, a more villous portion of the placental disk forms before the formation of a more compact labyrinth. Although the definitive placenta is cellular haemomonochorial, it lacks the spongy zone found in the Tenrecinae. Neither does it resemble the endotheliochorial condition found in the Potamogalinae. Of the two genera of the subfamily Oryzorictinae represented by single specimens, the placenta of Limnogale resembled that of the Microgale but Oryzorictes had several differences including a lobulated placental disk. It is concluded that there is more variation in placentation both within the subfamily Oryzorictinae and within the family Tenrecidae than would ordinarily be expected. PMID:17113148

  12. [The role of hybrid zones in speciation: a case study on chromosome races of the house mouse Mus domesticus and common shrew Sorex araneus].

    PubMed

    Lavrenchenko, L A; Bulatova, N Sh

    2015-01-01

    Although diverse complexes of chromosome races are of rather rare occurrence in mammals, that does not reduce its importance to insignificant phenomenon not worthy of studying as some unique case without direct analogy. Moreover, these complexes present virtually ideal models for estimation of the impact of hybridization on the process of microevolution. The chromosome races are characterized by almost zero level of genetic differentiation and well-defined distinctions, usually induced by chromosome rearrangements only. The presented review shows the valuable contribution of the studies on Sorex araneus and Mus domesticus chromosome Robertsonian systems into our understanding of varied impact