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1

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

USGS Publications Warehouse

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.

Woodman, Neal; Gaffney, Sarah A.

2014-01-01

2

Phylogeny and Evolution of African Shrews (Mammalia: Soricidae) Inferred from 16s rRNA Sequences  

Microsoft Academic Search

Current phylogenetic hypotheses on the African Crocidurinae (Soricidae) are based upon morpho-anatomical, karyological, and allozyme studies. The present study attempts to resolve the interrelationships among African Crocidurinae and their relationships to Eurasian Crocidurinae and to the subfamily Soricinae, on the basis of partial mitochondrial 16s rRNA sequences (549 bp). This is the first molecular study to include all but one

Sophie Quérouil; Rainer Hutterer; Patrick Barrière; Marc Colyn; Julian C. Kerbis Peterhans; Erik Verheyen

2001-01-01

3

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

USGS Publications Warehouse

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.

Woodman, Neal; Stephens, Ryan B.

2010-01-01

4

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

USGS Publications Warehouse

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.

Woodman, N.

2002-01-01

5

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

USGS Publications Warehouse

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.

Woodman, N.

2003-01-01

6

Taxonomy and evolutionary relationships of Phillips’ small-eared shrew, Cryptotis phillipsii (Schaldach, 1966), from Oaxaca, Mexico (Mammalia: Insectivora: Soricidae)  

E-print Network

subspecies), and the monotypic Cryptotis goodwini comprised the C. mexicana-group. Based on cranial and postcranial morphology (in particular, unique modifications of the fore- limb) and biogeographic patterns, we (Woodman & Timm 1999) recently revised... agreed with Choate's as- sessment, referring material from the Sierra de Cuatro Venados and the Sierra de Mia- huatlan to the species Cryptotis peregrina (Woodman & Timm 1999). Cranially, the shrews previously considered by Choate (1970...

Woodman, Neal; Timm, Robert M.

2000-07-01

7

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

USGS Publications Warehouse

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.

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

2012-01-01

8

Revision of the extant taxa of the genus Notiosorex (Mammalia: Insectivora: Soricidae)  

E-print Network

We evaluated the taxonomic status of three specimens of gray shrews, Notiosorex (Insectivora: Soricidae), collected in isolated mountain valleys in Tamaulipas, Mexico, with specimens referable to the Recent taxa N. crawfordi ...

Carraway, Leslie N.; Timm, Robert M.

2000-04-01

9

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

USGS Publications Warehouse

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).

Woodman, Neal

2012-01-01

10

Spatial analysis of species richness of shrews (Soricomorpha: Soricidae) in North America north of Mexico  

Microsoft Academic Search

We used geographic ranges of North American shrews and environmental data to better understand spatial distribution of species\\u000a richness in the Soricidae. Richness was examined as a function of latitude and longitude and was compared with climatic variables\\u000a at random points (?90 km apart). Latitudinal trend in richness was parabolic with a maximum near 48°N, consistent with the\\u000a general hypothesis

Jesse Berman; Timothy McCay; Peter Scull

2007-01-01

11

Phylogeographical footprints of the Strait of Gibraltar and Quaternary climatic fluctuations in the western Mediterranean: a case study with the greater white-toothed shrew, Crocidura russula (Mammalia: Soricidae)  

Microsoft Academic Search

We used mitochondrial cyt b sequences to investigate the phylogenetic relationships of Crocidura russula ( sensu lato ) populations across the Strait of Gibraltar, western Europe, Maghreb, and the Mediterranean and Atlantic islands. This revealed very low genetic divergence between European and Moroccan populations. The application of a molecular clock previously calibrated for shrews suggested that the separation of European

JEAN-FRANÇOIS COSSON; RAINER HUTTERER; ROLAND LIBOIS; MAURIZIO SARÀ; PETER VOGEL

12

Molecular Phylogeny of Short-Tailed Shrews, Blarina (Insectivora: Soricidae)  

Microsoft Academic Search

Phylogenetic relationships among the three described species of short-tailed shrews (genus Blarina) were inferred based on mitochondrial DNA sequences of 16S rRNA (506 bp) and cytochrome b (1137 bp) from 38 specimens representing B. brevicauda, B. hylophaga, and B. carolinensis, from across their range in North America. Phylogenetic analyses of both data sets combined followed tests showing lack of incongruence

Sara V. Brant; Guillermo Ort??

2002-01-01

13

Molecular phylogeny of short-tailed shrews, Blarina (Insectivora: Soricidae).  

PubMed

Phylogenetic relationships among the three described species of short-tailed shrews (genus Blarina) were inferred based on mitochondrial DNA sequences of 16S rRNA (506 bp) and cytochrome b (1137 bp) from 38 specimens representing B. brevicauda, B. hylophaga, and B. carolinensis, from across their range in North America. Phylogenetic analyses of both data sets combined followed tests showing lack of incongruence between these fragments. Analysis of substitution patterns indicated saturation of transitions at third codon positions in cytochrome b when Blarina sequences were compared to those of Sorex and Cryptotis, used as outgroups. Maximum-likelihood and weighted parsimony supported the monophyly of the genus and placed B. hylophaga as its basal branch, sister to B. brevicauda + B. carolinensis. Phylogeographic analysis revealed a significant partition between eastern and western populations of B. carolinensis and B. brevicauda, on either side of the Mississippi basin. These results are discussed in relation to cytogenetic, morphological, and fossil data. PMID:11820838

Brant, Sara V; Ortí, Guillermo

2002-02-01

14

High-latitude diversification within Eurasian least shrews and Alaska tiny shrews (Soricidae)  

E-print Network

Biology, University of New Mexico, Albuquerque, NM 87131, USA (AGH, SOM, JAC) Department of Biomedical recently in Alaska and described based on morphological characters as Sorex yukonicus. This species on genetic variability through a phylogeographic analysis of both species of shrew using evidence from 3

15

Helminths of the vagrant shrew, Sorex vagrans , from western Montana, USA  

Microsoft Academic Search

A total of 19 helminth species (1 trematode, 11 cestodes, 7 nematodes) were collected from 45 vagrant shrews, Sorex vagrans (Mammalia, Soricidae), in western Montana, USA. One trematode (Brachylaima sp.), 2 cestodes (Paruterina candelabraria, Staphylocystoides longi), and 6 nematodes (Baruscapillaria rauschi, Eucoleus oesophagicola, Longistriata meylani, Paracrenosoma sp., Parastrongyloides winchesi, Pseudophysaloptera formosana) are reported for the first time from this host.

John M. Kinsella

2007-01-01

16

Fine structure of the submandibular salivary gland of the venomous short-tailed shrew, Blarina brevicauda Say (Insectivora: Soricidae).  

PubMed

Adult male short-tailed shrews, Blarina brevicauda, (Insectivora: Soricidae) were trapped in Virginia and Pennsylvania, anesthetized, and perfused via the left ventricle of the heart with fixative. The submandibular glands were dissected free and prepared for transmission electron microscopy. The lobular, compound tubuloacinar glands had secretory endpieces consisting of seromucous acini and serous tubules connected to intercalated ducts, granular ducts, striated ducts, and excretory ducts. The general cytology of the submandibular gland of Blarina shared morphological characters with individuals in several other mammalian orders and yet differed in many ways from another Insectivore, the European hedgehog, Erinaceus europaeus. PMID:8398545

Carson, K A; Rose, R K

1993-01-01

17

First evidence of poisonous shrews with an envenomation apparatus  

Microsoft Academic Search

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\\u000a from two Early Pleistocene cave deposits of the Sierra de Atapuerca in Burgos, Spain. The two soricine taxa from Atapuerca\\u000a have evolved specialized teeth as EAs, which

Gloria Cuenca-Bescós; Juan Rofes

2007-01-01

18

The morphology of hymenolepidid and dilepidid cestodes from common and pygmy shrews (Soricidae) in southeast England.  

PubMed

One hundred and six of 109 common shrews (Sorex araneus) and 62 of 72 pygmy shrews (S. minutus), obtained by Longworth trapping in Southeast England, were infected with cestodes. Ten species were recovered: Choanotaenia hepatica and Hymenolepis prolifer (found in S. araneus); Choanotaenia crassiscolex, Hymenolepis furcata, H. jacutensis, H. schaldybini, H. scutigera, H. singularis, H. diaphana and H. infirma (in both hosts). The morphology, taxonomy and ecology of these species are discussed and the findings of the present study are discussed with reference to previous studies of the helminth fauna of British shrews. Cysticercoids of C. crassiscolex were found in the snail, Vitrina pellucida, and cysticercoids of H. schaldybini in the staphylinid beetle, Anthobium unicolor. PMID:7829846

Roots, C D; Lewis, J W; Churchfield, J S

1994-09-01

19

The maritime shrew, Sorex maritimensis (Insectivora: Soricidae): a newly recognized Canadian endemic  

Microsoft Academic Search

Previous morphological and cytological analyses have suggested that the arctic shrew (Sorex arcticus )a s currently recognized may be two distinct species. Specifically, those studies demonstrated considerable differentiation between the putative subspecies S. a. maritimensis and one or both of the other two subspecies, S. a. arcticus and S. a. laricorum. Phylogenetic analysis of 546 base pairs of cytochrome b

Donald T. Stewart; Neil D. Perry; Luca Fumagalli

2002-01-01

20

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

USGS Publications Warehouse

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.

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

2011-01-01

21

Karyotypes of shrews of the genera Cryptotis and Blarina (mammalia: Soricidae)  

Microsoft Academic Search

Summary Cryptotis parva has a diploid number of 52 and a fundamental number of 50. Blarina brevicauda in Nebraska and Pennsylvania has a diploid number of 49 or 50 and a fundamental number of 48. Blarina carolinensis in Nebraska and Kansas has a diploid number of 52 and a fundamental number of 62. The X-chromosome in all 3 species is

H. H. Genoways; J. C. Patton; J. R. Choate

1977-01-01

22

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

USGS Publications Warehouse

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.

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

2014-01-01

23

First results on the feeding ecology of sympatric shrews (Insectivora: Soricidae) in the Tai National Park, Ivory Coast  

Microsoft Academic Search

The feeding ecology of a multi-species community of shrews inhabiting secondary forest and cacao-coffee plantations in the\\u000a Tai National Park (Ivory Coast) was investigated. A total of 553 shrews were captured and 194 alimentary tracts were examined.\\u000a Ten species were found, includingSylvisorex megalura and nine species ofCrocidura, forming a series with respect to body size. New ecological data on these

Sara Churchfield; Patrick Barrière; Rainer Hutterer; Marc Colyn

2004-01-01

24

Characterisation of a unique dipeptidase allele in an insular population of masked shrews, Sorex cinereus (Insectivora: Soricidae)  

Microsoft Academic Search

The masked shrew, Sorex cinereus, is found in extremely high densities on Bon Portage Island, off the southern coast of Nova Scotia, Canada. This population is sustained by abundant amphipods and kelp flies living in large beds of decaying seaweed. Littoral feeding has not been demonstrated in other Sorex cinereus populations. This population is also distinct in that it contains

Iain S. MacPherson; Donald T. Stewart

2003-01-01

25

Population genetic structure of Sorex unguiculatus and Sorex caecutiens (Soricidae, Mammalia) in Hokkaido, based on microsatellite DNA polymorphism  

Microsoft Academic Search

We investigated the genetic structure of Sorex unguiculatus and Sorex caecutiens populations in Hokkaido, Japan, using hypervariable microsatellite DNA markers. We used five microsatellite loci to type 475 S. unguiculatus individuals from 20 localities on the Hokkaido mainland and four localities from each of four offshore islands (and 11 shrews from one locality in southern Sakhalin for a particular analysis).

Yukako Naitoh; Satoshi D. Ohdachi

2006-01-01

26

Phylogeography of the dusky shrew, Sorex monticolus (Insectivora, Soricidae): insight into deep and shallow history in northwestern North America.  

PubMed

Phylogenetic relationships among the dusky shrew (Sorexmonticolus) and eight related species (S. bairdi, S. bendirii, S. neomexicanus, S.ornatus, S. pacificus, S. palustris, S. sonomae and S.vagrans) were assessed using sequences from the mitochondrial cytochrome b gene (801 bp). Analyses using parsimony and maximum likelihood revealed significant molecular variation not reflected in previous morphological studies of these species. Conversely, three morphologically defined species (S.bairdi, S.neomexicanus and S.pacificus) were poorly differentiated. Sorexornatus and S.vagrans represented basal taxa for a more inclusive group that included: (i) a widespread Continental clade containing S.monticolus (Arizona to Alaska, including S. neomexicanus); (ii) a Coastal clade containing S.monticolus (Oregon to south-east Alaska, including S. bairdi and S. pacificus); (iii) the semiaquatic species (S. bendirii and S. palustris); and (iv) S.sonomae. Additional subdivision was observed within the Continental clade corresponding to populations from the northern and southern Rocky Mountains. Average uncorrected sequence divergence between the Coastal and Continental clades was 5.3% (range 4.5-6.2%), which exceeds many interspecific comparisons within this species complex and within the genus Sorex. Lack of resolution of internal nodes within topologies suggests a deep history of rapid diversification within this group. Late Pleistocene/Holocene glacial perturbations are reflected in the shallow phylogeographic structure within these clades in western North America. Our results suggest also that S. monticolus is not monophyletic under current taxonomic nomenclature. This perspective on phylogeographic history was developed within a growing comparative framework for other organisms in western North America. PMID:11380879

Demboski, J R; Cook, J A

2001-05-01

27

Biogeographical and Evolutionary Relationships Among Central American Small-Eared Shrews of the Genus Cryptotis (Mammalia: Insectivora: Soricidae)  

E-print Network

Cryptotis gracilis (20).—COSTA RICA: CARTAGO: Volcán Irazú, Finca Coliblanco, 2350 m (2 UMMZ); Volcán Irazú, .25 mi N of San Juan Chicoa, 2860 m (1 UMMZ); Volcán Irazú, 2500 m (1 KU); Volcán Turrialba, Hacienda El Retiro, 2590 m (4 UMMZ). SAN JÓSE: Cerro..., 3) the Volcán Irazú/Volcán Turrialba complex in the Central Cordillera, and 4) the Talamancan Cordillera of southern Costa Rica and the adjoining Chiriqui Cordillera of westernmost Panama (Fig. 9). Further study of specimens from these regions...

Woodman, Neal

1992-09-09

28

Geographic variation and evolutionary relationships among broad-clawed shrews of the Cryptotis goldmani–group (Mammalia: Insectivora: Soricidae)  

E-print Network

. James W. Bee (KU unpublished field cat- alog, 1954, 1955) recorded taking Sorex verae- pacis, Microtus guatemalensis, Peromyscus gua- temalensis, Reithrodontomys microdon, Reithro- dontomys sumichrasti, and Reithrodontomys ten- uirostris along..., Peromyscus levipes, Reithrodontomys fulvescens, Reithrodontomys mexicanus, R. sumichrasti, and Scotinomy tegui- na. Reproductive data for Cryptotis goodwini goodwini are lacking. Our inspection of study skins of males taken from 4 to 15 January (n = 6...

Woodman, Neal; Timm, Robert M.

1999-01-01

29

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

USGS Publications Warehouse

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.

Woodman, Neal

2013-01-01

30

First evidence of poisonous shrews with an envenomation apparatus  

NASA Astrophysics Data System (ADS)

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.

Cuenca-Bescós, Gloria; Rofes, Juan

2007-02-01

31

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

PubMed Central

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

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

2012-01-01

32

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

Microsoft Academic Search

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

Alessio Mortelliti; Luigi Boitani

2009-01-01

33

Maximal enzyme activities, and myoglobin and glutathione concentrations in heart, liver and skeletal muscle of the Northern Short-tailed shrew ( Blarina brevicauda; Insectivora: Soricidae)  

Microsoft Academic Search

We measured the enzymes of glycolysis, Krebs Cycle, ?-oxidation and electron transport in the heart, liver and skeletal muscle of the Northern Short-tailed Shrew, Blarina brevicauda. Additionally, we measured the amount of myoglobin in skeletal and heart muscle as well as the concentration of glutathione in heart. The picture that emerges is of an aerobically well-endowed animal with constrained anaerobic

J. M. Stewart; A. K. Woods; J. A. Blakely

2005-01-01

34

Coccidian parasites (Apicomplexa: Eimeriidae) from insectivores. III. Seven new species in shrews (Soricidae: Soricinae) from Canada, Japan, and the United States.  

PubMed

Since May 1979, 458 shrews (Blarina sp. and Sorex spp.) representing 20 species collected in Canada, Japan, and the United States were examined for coccidia; 110 (24%) had oocysts in their feces, including 8 of 21 (38%) B. brevicauda from Massachusetts, Ohio, Pennsylvania, and Vermont; 2 of 7 (29%) S. caecutiens from Hokkaido and Honshu; 14 of 63 (22%) S. cinereus from Colorado, New Mexico, Pennsylvania, Vermont, Manitoba, and Ontario; 3 of 7 (43%) S. fontinalis from Pennsylvania; 11 of 16 (69%) S. fumeus from Massachusetts, Minnesota, Pennsylvania, Vermont, and Ontario; 1 of 4 (25%) S. haydeni from Minnesota; 6 of 8 (75%) S. longirostris from Florida and Virginia; 1 of 2 (50%) S. ornatus from California; 5 of 12 (42%) S. pacificus from California and Oregon; 13 of 41 (32%) S. palustris from California, Colorado, and New Mexico; 1 of 2 (50%) S. tenellus from California; 11 of 105 (10%) S. trowbridgii from California, Oregon, and Washington; 10 of 48 (21%) S. unguiculatus from Hokkaido; and 24 of 112 (21%) S. vagrans from Arizona, California, Colorado, New Mexico, Oregon, and Washington. The following coccidians were identified from infected shrews: Eimeria brevicauda n. sp. from B. brevicauda; Eimeria fumeus n. sp. from S. fumeus, S. pacificus, S. unguiculatus, and S. vagrans; Eimeria inyoni n. sp. from S. tenellus; Eimeria palustris n. sp. from S. cinereus, S. fontinalis, S. fumeus, S. haydeni, S. longirostris, S. ornatus, S. pacificus, S. palustris, S. tenellus, S. trowbridgii, and S. vagrans; Eimeria vagrantis n. sp. from S. fumeus, S. trowbridgii, and S. vagrans; Isospora brevicauda n. sp. from B. brevicauda; and Isospora palustris n. sp. from S. pacificus, S. palustris, S. trowbridgii, S. unguiculatus, and S. vagrans. The world literature on coccidian parasites of shrews (16 eimerians and 3 isosporans exclusive of the 7 new species described here) is reviewed. PMID:3572649

Hertel, L A; Duszynski, D W

1987-02-01

35

Evolution of mtDNA D-loop sequences and their use in phylogenetic studies of shrews in the subgenus Otisorex (Sorex: Soricidae: Insectivora).  

PubMed

mtDNA D-loop sequences were examined in shrews of the genus Sorex. All specimens possessed an array of tandem repeats in which each repeat was 78 to 80 base pairs (bp) in length. Each specimen also possessed a 76-bp imperfect copy of the tandem repeats. Three observations are consistent with the tandem repeats being the product of concerted evolution: (1) the repeats are capable of forming secondary structures; (2) there was minimal sequence divergence between tandem repeats within individuals; and (3) although the tandem repeats and the imperfect repeat presumably arose due to a duplication event in an ancestor of the shrews, the imperfect repeat per se was not copied in any of the specimens observed. Interspecific homology can therefore be assumed for the imperfect repeat. Furthermore, given the apparent high rate of concerted evolution within a genome, tandem repeats in different individuals may be compared as though only a single copy were present. By including data from the imperfect repeat, the last tandem repeat, and the surrounding unique sequence cladistic and genetic distance approaches to phylogeny reconstruction indicated two sister groups within the subgenus Otisorex. One group was composed of Sorex fumeus and the S. cinereus species complex and the other group was composed of S. hoyi, S. monticolus, S. vagrans, and S. palustris. Resolution of relationships among recently evolved taxa demonstrated the usefulness of selected regions of the D-loop for molecular systematic studies. PMID:8025728

Stewart, D T; Baker, A J

1994-03-01

36

Maximal enzyme activities, and myoglobin and glutathione concentrations in heart, liver and skeletal muscle of the Northern Short-tailed shrew (Blarina brevicauda; Insectivora: Soricidae).  

PubMed

We measured the enzymes of glycolysis, Krebs Cycle, beta-oxidation and electron transport in the heart, liver and skeletal muscle of the Northern Short-tailed Shrew, Blarina brevicauda. Additionally, we measured the amount of myoglobin in skeletal and heart muscle as well as the concentration of glutathione in heart. The picture that emerges is of an aerobically well-endowed animal with constrained anaerobic capacity as indicated by small activities of glycolytic enzymes and creatine kinase. Lipid metabolism and amino acid transamination, as well as gluconeogenesis, are predominant in processing carbon resources and probably reflect the large contribution lipid and protein make to the diet of this carnivore. The citrate synthase activity is the largest of any reported value for vertebrate heart (250 U/g). The additional, very active cytochrome c oxidase activity (220 U/g) and large myoglobin concentrations (8 mg/g) in heart are clearly the underpinnings of the rapid metabolic rates reported for small insectivores. The potential for generation of reactive oxygen species must be great since the total glutathione concentration (165 mumol/g) is 300-fold greater in shrew hearts than in hearts of rats. PMID:15914053

Stewart, J M; Woods, A K; Blakely, J A

2005-07-01

37

Novel hantavirus in the flat-skulled shrew (Sorex roboratus). Vector Borne Zoonotic Dis  

E-print Network

Genetically distinct hantaviruses have been identified recently in multiple species of shrews (Order Soricomorpha, Family Soricidae) in Eurasia and North America. To corroborate decades-old reports of hantaviral antigens in shrews from Russia, archival liver and lung tissues from 4 Siberian large-toothed shrews (Sorex

Hae Ji Kang; Satoru Arai; Andrew G. Hope; Joseph A. Cook; Richard Yanagihara; Key Words Hantavirus—pcr—zoonosis

2010-01-01

38

Short Report: Phylogenetically Distinct Hantaviruses in the Masked Shre w( Sorex cinereus) and Dusky Shrew (Sorex monticolus) in the United States  

Microsoft Academic Search

A limited search for hantaviruses in lung and liver tissues of Sorex shrews (family Soricidae, subfamily Soricinae) revealed phylogenetically distinct hantaviruses in the masked shrew (Sorex cinereus) from Minnesota and in the dusky shrew (Sorex monticolus) from New Mexico and Colorado. The discovery of these shrew-borne hantaviruses, named Ash River virus and Jemez Springs virus, respectively, challenges the long-held dogma

Satoru Arai; Shannon N. Bennett; Laarni Sumibcay; Joseph A. Cook; Jin-Won Song; Andrew Hope; Cheryl Parmenter; Vivek R. Nerurkar; Terry L. Yates; Richard Yanagihara

2008-01-01

39

JA (2001) Phylogeography of the dusky shrew, Sorex monticolus (Insectivora, Soricidae): insight into deep and shallow history in northwestern North America  

E-print Network

Phylogenetic relationships among the dusky shrew (Sorex monticolus) and eight related species (S. bairdi, S. bendirii, S. neomexicanus, S. ornatus, S. pacificus, S. palustris, S. sonomae and S. vagrans) were assessed using sequences from the mitochondrial cytochrome b gene (801 bp). Analyses using parsimony and maximum likelihood revealed significant molecular variation not reflected in previous morphological studies of these species. Conversely, three morphologically defined species (S. bairdi, S. neomexicanus and S. pacificus) were poorly differentiated. Sorex ornatus and S. vagrans represented basal taxa for a more inclusive group that included: (i) a widespread Continental clade containing S. monticolus (Arizona to Alaska, including S. neomexicanus); (ii) a Coastal clade containing S. monticolus (Oregon to south-east Alaska, including S. bairdi and S. pacificus); (iii) the semiaquatic species (S. bendirii and S. palustris); and (iv) S. sonomae. Additional subdivision was observed within the Continental clade corresponding to populations from the northern and southern Rocky Mountains. Average uncorrected sequence divergence between the Coastal and Continental clades was 5.3 % (range 4.5–6.2%), which exceeds many interspecific comparisons within this species

John R. Demboski; Joseph A. Cook

40

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

PubMed Central

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 (= event–pairs) 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

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

2004-01-01

41

Novel Hantavirus in the Flat-Skulled Shrew (Sorex roboratus)  

PubMed Central

Abstract Genetically distinct hantaviruses have been identified recently in multiple species of shrews (Order Soricomorpha, Family Soricidae) in Eurasia and North America. To corroborate decades-old reports of hantaviral antigens in shrews from Russia, archival liver and lung tissues from 4 Siberian large-toothed shrews (Sorex daphaenodon), 5 Eurasian least shrews (Sorex minutissimus), 12 flat-skulled shrews (Sorex roboratus), and 18 tundra shrews (Sorex tundrensis), captured in the Sakha Republic in northeastern Siberia during July and August 2006, were analyzed for hantavirus RNA by reverse transcription–polymerase chain reaction. A novel hantavirus, named Kenkeme virus, was detected in a flat-skulled shrew. Sequence analysis of the full-length S and partial M and L segments indicated that Kenkeme virus was genetically and phylogenetically distinct from Seewis virus harbored by the Eurasian common shrew (Sorex araneus), as well as all other rodent-, soricid-, and talpid-borne hantaviruses. PMID:20426682

Kang, Hae Ji; Arai, Satoru; Hope, Andrew G.; Cook, Joseph A.

2010-01-01

42

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

PubMed Central

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

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

2012-01-01

43

Phylogenetically distinct hantaviruses in the masked shrew (Sorex cinereus) and dusky shrew (Sorex monticolus) in the United States.  

PubMed

A limited search for hantaviruses in lung and liver tissues of Sorex shrews (family Soricidae, subfamily Soricinae) revealed phylogenetically distinct hantaviruses in the masked shrew (Sorex cinereus) from Minnesota and in the dusky shrew (Sorex monticolus) from New Mexico and Colorado. The discovery of these shrew-borne hantaviruses, named Ash River virus and Jemez Springs virus, respectively, challenges the long-held dogma that rodents are the sole reservoir hosts and forces a re-examination of their co-evolutionary history. Also, studies now underway are aimed at clarifying the epizootiology and pathogenicity of these new members of the genus Hantavirus. PMID:18256444

Arai, Satoru; Bennett, Shannon N; Sumibcay, Laarni; Cook, Joseph A; Song, Jin-Won; Hope, Andrew; Parmenter, Cheryl; Nerurkar, Vivek R; Yates, Terry L; Yanagihara, Richard

2008-02-01

44

Short Report: Phylogenetically Distinct Hantaviruses in the Masked Shrew (Sorex cinereus) and Dusky Shrew (Sorex monticolus) in the United States  

PubMed Central

A limited search for hantaviruses in lung and liver tissues of Sorex shrews (family Soricidae, subfamily Soricinae) revealed phylogenetically distinct hantaviruses in the masked shrew (Sorex cinereus) from Minnesota and in the dusky shrew (Sorex monticolus) from New Mexico and Colorado. The discovery of these shrew-borne hantaviruses, named Ash River virus and Jemez Springs virus, respectively, challenges the long-held dogma that rodents are the sole reservoir hosts and forces a re-examination of their co-evolutionary history. Also, studies now underway are aimed at clarifying the epizootiology and pathogenicity of these new members of the genus Hantavirus. PMID:18256444

Arai, Satoru; Bennett, Shannon N.; Sumibcay, Laarni; Cook, Joseph A.; Song, Jin-Won; Hope, Andrew; Parmenter, Cheryl; Nerurkar, Vivek R.; Yates, Terry L.; Yanagihara, Richard

2008-01-01

45

Ultrastructure of the Eimer's organs of the Japanese shrew mole, Urotrichus talpoides (Insectivora, Mammalia) and their changes following infraorbital axotomy.  

PubMed

The Eimer's organ and adjacent structures and their changes after infraorbital axotomy was examined with LM, TEM and SEM in the Japanese shrew mole, Urotrichus talpoides. Approximately 3,000 of Eimer's organ covers the hairless snout tip of this animal. It protrudes to the corium from epidermis, and consists of column-shaped core and the cylindrical peripheral structures. About a dozen of naked fibers ascend vertically in the core; one or a few of them runs amidst the core and the others along its circumferential part. Each fiber has shelf-like endings one in each of 5 to 7 succeeding cells in the upper part of the core. At the uppermost part of the core structure is an opaque degenerating cell. Neurites were considered to grow up with the epidermal cells to which their endings are attached. This pattern of nerve ending was clearly observed for the first time in this study. Usually 3 Merkel cells lie at the base of an Eimer's organ contacting with a soup-plate-shape nerve terminal. In the dermis, an encapsulated corpuscle enveloping a nerve endings is found underneath each Eimer's organ. After axotomy, ipsilateral nerve fibers and their endings totally disappeared from Eimer's organ in a week. Perforation in the domes, flattening of the dome surface, and degeneration of the encapsulated corpuscles appeared on the transected side. In addition to this, several features of degeneration also appeared on the contralateral side. It might be considered as an effect of disuse from the disorders of the other side. PMID:3400878

Shibanai, S

1988-01-01

46

Muscle aging and oxidative stress in wild-caught shrews  

Microsoft Academic Search

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 (<18months) 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

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

2010-01-01

47

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

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.

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

2013-01-01

48

Evidence for gene flow in parasitic nematodes between two host species of shrews  

Microsoft Academic Search

We describe the genetic structure of populations of the intestinal nematode Longistriata caudabullata (Trichostrongyloidea: Heligmosomidae), a common parasite of short-tailed shrews (genus Blarina , Insectivora: Soricidae). Parasites and hosts were collected from a transect across a contact zone between two species of hosts, Blarina brevicauda and B. hylo- phaga, in central North America. An 800-base pairs (bp) fragment of the

Sara V. Brant; Guillermo Orti

2003-01-01

49

Muscle aging and oxidative stress in wild-caught shrews.  

PubMed

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 (<18months) 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 2x 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

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

2010-04-01

50

Muscle Aging and Oxidative Stress in Wild-Caught Shrews  

PubMed Central

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

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

2010-01-01

51

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

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

2012-01-01

52

Sorex rohweri sp. nov. (Mammalia, Soricidae) from northwestern North America  

Microsoft Academic Search

Sorex rohweri sp. nov. is described on the basis of a series of specimens from the Olympic Peninsula and adjacent western regions of Washington State, USA, and southwestern British Columbia, Canada. It has been misidentified as Sorex cinereus Kerr, 1792, which occurs in the Cascade Range in west-central Washington, in coastal British Columbia, and regions farther to the northeast. The

R. L. Rausch; Jean. E. Feagin; Virginia R. Rausch

2007-01-01

53

Short Report: Phylogenetically Distinct Hantaviruses in the Masked Shrew (Sorex cinereus) and Dusky Shrew (Sorex monticolus) in the United States  

E-print Network

Abstract. A limited search for hantaviruses in lung and liver tissues of Sorex shrews (family Soricidae, subfamily Soricinae) revealed phylogenetically distinct hantaviruses in the masked shrew (Sorex cinereus) from Minnesota and in the dusky shrew (Sorex monticolus) from New Mexico and Colorado. The discovery of these shrew-borne hantaviruses, named Ash River virus and Jemez Springs virus, respectively, challenges the long-held dogma that rodents are the sole reservoir hosts and forces a re-examination of their co-evolutionary history. Also, studies now underway are aimed at clarifying the epizootiology and pathogenicity of these new members of the genus Hantavirus. Based on phylogenetic analyses of full-length viral genomic sequences and host mitochondrial DNA (mtDNA) sequences, hantaviruses segregate into clades that parallel the evolution of murinae, arvicolinae, neotominae, and sigmodontinae rodents. 1–4 Whether insectivores (or soricomorphs), which are sympatric with rodents, are involved in the evolutionary origins of hantaviruses has not been systematically studied, despite previous reports of hantavirus antigens in tissues of the Eurasian common shrew (Sorex araneus), alpine

Satoru Arai; Shannon N. Bennett; Laarni Sumibcay; Joseph A. Cook; Jin-won Song; Andrew Hope; Cheryl Parmenter; Vivek R. Nerurkar; Terry L. Yates; Richard Yanagihara

54

Leptospira spp. in Rodents and Shrews in Germany  

PubMed Central

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

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

2014-01-01

55

Leptospira spp. in rodents and shrews in Germany.  

PubMed

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

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

2014-08-01

56

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

PubMed Central

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

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

57

Evidence for gene flow in parasitic nematodes between two host species of shrews.  

PubMed

We describe the genetic structure of populations of the intestinal nematode Longistriata caudabullata (Trichostrongyloidea: Heligmosomidae), a common parasite of short-tailed shrews (genus Blarina, Insectivora: Soricidae). Parasites and hosts were collected from a transect across a contact zone between two species of hosts, Blarina brevicauda and B. hylophaga, in central North America. An 800-base pairs (bp) fragment of the ND4 mitochondrial DNA (mtDNA) gene was sequenced for 28 worms and a 783-bp fragment of the mtDNA control region was analysed for 16 shrews. Phylogenetic analyses of mtDNA sequences revealed reciprocal monophyly for the shrew species, concordant with morphological diagnosis, and supported the idea that the transect cuts through a secondary contact zone between well-differentiated B. brevicauda and B. hylophaga. In contrast to this pattern, the parasitic nematode mtDNA phylogeny was not subdivided according to host affiliation. Genealogical discordance between parasite and host phylogenies suggests extensive gene flow among parasites across the host species boundary. PMID:12969487

Brant, Sara V; Ortí, Guillermo

2003-10-01

58

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

E-print Network

of New Mexico, Albuquerque, NM 87131, USA, Alaska Science Center, US Geological Survey, 4210 University Drive, Anchorage, AK 99508, USA, Department of Biomedical Sciences, Tufts University Cummings School, species movements, community turnover and diversification and yet in many respects these dynamics

59

American Society of Mammalogists A New Species of Shrew (Soricidae, Insectivora) from Alaska  

E-print Network

to be widespread, but scarce, from Scandinavia to the Bering Strait. In September 1993, a single speci- men of tiny with an Eurasian affiliation on the eastern side of the Bering Strait. The recent biota on either side of the Bering Strait, originating in the Pleistocene glacial refug- ium known as Beringia (Chernyavsky, 1984

Sullivan, Jack

60

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

USGS Publications Warehouse

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.

Woodman, N.

2004-01-01

61

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

PubMed Central

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

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

2013-01-01

62

Novel Hantavirus in the Flat-Skulled Shrew (Sorex roboratus)  

E-print Network

) in the dusky shrew (Sorex monticolus) (Arai et al. 2008a), and Imjin virus (MJNV) in the Ussuri whiteNovel Hantavirus in the Flat-Skulled Shrew (Sorex roboratus) Hae Ji Kang,1 Satoru Arai,2 Andrew G liver and lung tissues from 4 Siberian large-toothed shrews (Sorex daphaenodon), 5 Eurasian least shrews

63

The Taming of the Shrew  

NASA Astrophysics Data System (ADS)

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.

Gad-El-Hak, M.

1996-11-01

64

Shrews — Small Insectivores with Polyphasic Patterns  

Microsoft Academic Search

\\u000a Daily activity patterns of shrews are controlled by metabolic requirements commensurate with their diminutive body mass and\\u000a resultant high surfaceto-mass ratios: they must forage often to avoid exhaustion of their energy stores. To remain homeothermic,\\u000a shrews must partition a 24-h period into multiple bouts of foraging, rest, and sleep.

Joseph F. Merritt; Stephen H. Vessey

65

Short Report: Phylogenetically Distinct Hantaviruses in the Masked Shrew (Sorex cinereus) and Dusky Shrew (Sorex monticolus) in the United States  

E-print Network

Shrew (Sorex monticolus) in the United States Satoru Arai, Shannon N. Bennett, Laarni Sumibcay, Joseph A hantaviruses in the masked shrew (Sorex cinereus) from Minnesota and in the dusky shrew (Sorex monticolus) fromShort Report: Phylogenetically Distinct Hantaviruses in the Masked Shrew (Sorex cinereus) and Dusky

66

The neurobiology of Etruscan shrew active touch  

PubMed Central

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 36°C to 24°C, 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

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

2011-01-01

67

Rediscovery of Enders’s small-eared shrew, Cryptotis endersi (Insectivora: Soricidae), with a redescription of the species  

E-print Network

C77C97C109C109C46 C98C105C111C108C46 C54C55 C40C50C48C48C50C41 C51C55C50C177C51C55C55 C77C97C109C109C97C108C105C97C110 C66C105C111C108C111C103C121 C227 C85C114C98C97C110 C38 C70C105C115C99C104C101C114 C86C101C114C108C97C103 C104C116C116C112C58C47C47...C119C119C119C46C117C114C98C97C110C102C105C115C99C104C101C114C46C100C101C47C106C111C117C114C110C97C108C115C47C109C97C109C109C98C105C111C108 C90C101C105C116C115C99C104C114C105C102C116 C102C117C200C114C83C97C200C117C103C101C116C105C101C114C107C117C110C...

Pine, Ronald H.; Woodman, Neal; Timm, Robert M.

2002-12-01

68

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

Microsoft Academic Search

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

Sara V. Brant; Guillermo Orti

2003-01-01

69

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

PubMed

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

Brant, Sara V; Ortí, Guillermo

2003-06-01

70

Active Touch During Shrew Prey Capture  

PubMed Central

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

Munz, Martin; Brecht, Michael; Wolfe, Jason

2010-01-01

71

Shrew metabolic rates and thyroxine utilization.  

PubMed

Elevated basal metabolic rates (BMR) in shrews have been observed for over 40 years, yet no one has investigated the physiological basis for this phenomenon. This paper reports on investigations of thyroid function in a shrew (Sorex vagrans), and in three rodent species for comparison. The utilization rate of thyroxine in shrews is found to be much higher than for any of the rodents, and is correlated with BMR expressed as a percentage of the predicted BMR. It is concluded that the unusually high thyroxine utilization rates of Sorex are an important, if not the sole, determinant of their elevated metabolic rates. PMID:6147226

Tomasi, T

1984-01-01

72

Tripartite genetic subdivisions in the ornate shrew (Sorex ornatus)  

Microsoft Academic Search

We examined cytochrome b sequence variation in 251 ornate shrews ( Sorex ornatus ) from 20 localities distributed throughout their geographical range. Additionally, vagrant ( S. vagrans ) and montane ( S. monticolus ) shrews from four localities were used as outgroups. We found 24 haplotypes in ornate shrews from California (USA) and Baja California (Mexico) that differed by 1-31

Jesus E. Maldonado; Carles VilA; Robert K. Wayne

2001-01-01

73

Arsenic speciation, distribution, and bioaccessibility in shrews and their food.  

PubMed

Shrews (Sorex cinereus) collected at a historic mine in Nova Scotia, Canada, had approximately twice the arsenic body burden and 100 times greater daily intake of arsenic compared with shrews from a nearby uncontaminated background site. Shrews store arsenic as inorganic and simple methylated arsenicals. Much of the arsenic associated with their primary food source, i.e., small invertebrates, may be soil adsorbed to their exoskeletons. A physiologically based extraction test estimated that 47 ± 2% of invertebrate arsenic is bioaccessible in the shrew gastrointestinal tract. Overall, shrews appear to be efficient at processing and excreting inorganic arsenic. PMID:21986782

Moriarty, Maeve M; Koch, Iris; Reimer, Kenneth J

2012-04-01

74

Shrews in Managed Northern Hardwood Stands in the Allegheny Mountains of West Virginia  

E-print Network

. Capture frequency of masked shrews (Sorex cinereus), smoky shrews (S. fumeus), and northern short (S. dispar) and pygmy shrews (S. hoyi), both habitat specialists that our survey did not target, were

75

Newfound Hantavirus in Chinese Mole Shrew, Vietnam  

PubMed Central

Sequence analysis of the full-length medium segment and the partial small and large segments of a hantavirus, detected by reverse transcription–PCR 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

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

2007-01-01

76

Late Cenozoic History of the Genus Micromys (Mammalia, Rodentia) in Central Europe  

E-print Network

Late Cenozoic History of the Genus Micromys (Mammalia, Rodentia) in Central Europe Ivan Hora´cek1, Nadachowski A (2013) Late Cenozoic History of the Genus Micromys (Mammalia, Rodentia) in Central Europe. PLo

Horacek, Ivan

77

Tree shrew database (TreeshrewDB): a genomic knowledge base for the Chinese tree shrew.  

PubMed

The tree shrew (Tupaia belangeri) is a small mammal with a close relationship to primates and it has been proposed as an alternative experimental animal to primates in biomedical research. The recent release of a high-quality Chinese tree shrew genome enables more researchers to use this species as the model animal in their studies. With the aim to making the access to an extensively annotated genome database straightforward and easy, we have created the Tree shrew Database (TreeshrewDB). This is a web-based platform that integrates the currently available data from the tree shrew genome, including an updated gene set, with a systematic functional annotation and a mRNA expression pattern. In addition, to assist with automatic gene sequence analysis, we have integrated the common programs Blast, Muscle, GBrowse, GeneWise and codeml, into TreeshrewDB. We have also developed a pipeline for the analysis of positive selection. The user-friendly interface of TreeshrewDB, which is available at http://www.treeshrewdb.org, will undoubtedly help in many areas of biological research into the tree shrew. PMID:25413576

Fan, Yu; Yu, Dandan; Yao, Yong-Gang

2014-01-01

78

Lung parasites of shrews from Pennsylvania.  

PubMed

We examined lung parasites of three species of soricids, Sorex cinereus (n = 58), Sorex fumeus (n = 23) and Blarina brevicauda (n = 45) collected from Pennsylvania (USA), from 1990 to 1995. Yeast-like cells of Hisfoplasma capsulatum var. capsulatum were found in lung sections stained with Grocott's modification of Gomori's methenamine silver, periodic acid-Schiff, Giemsa, and hematoxylin-eosin in two (3%) S. cinereus, eight (35%) S. fumeus and two (4%) B. brevicauda. The number of spores of H. capsulatum in the lungs was low and no inflammatory reaction was evident. The infection was not disseminated to other organs. This is the first report of H. capsulatum infection in any species of shrews of the genus Sorex and the prevalence in S. fumeus was remarkably high compared to those reported for other wild mammals. A nematode, possibly Angiostrongylus michiganensis, was found in the lungs of one S. fumeus on necropsy and in a stained lung section of one S. cinereus. In both cases the host was also infected with the fungus. Pneumocystis carinii, which is the most common lung parasite in Sorex araneus (the numerically dominant Eurasian species of shrew), was not found in any of the North American species of shrew examined in this study. PMID:9131560

Laakkonen, J; Haukisalmi, V; Merritt, J F

1997-04-01

79

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

Microsoft Academic Search

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°C. Digesta passage rate trials were conducted before metabolic testing to estimate the minimum fasting time required for water shrews to achieve

R. W. Gusztak; R. A. MacArthur; K. L. Campbell

2005-01-01

80

Hantavirus in northern short-tailed shrew, United States.  

PubMed

Phylogenetic analyses, based on partial medium- and large-segment sequences, support an ancient evolutionary origin of a genetically distinct hantavirus detected by reverse transcription-PCR in tissues of northern short-tailed shrews (Blarina brevicauda) captured in Minnesota in August 1998. To our knowledge, this is the first evidence of hantaviruses harbored by shrews in the Americas. PMID:18252128

Arai, Satoru; Song, Jin-Won; Sumibcay, Laarni; Bennett, Shannon N; Nerurkar, Vivek R; Parmenter, Cheryl; Cook, Joseph A; Yates, Terry L; Yanagihara, Richard

2007-09-01

81

Hantavirus in Northern Short-tailed Shrew, United States  

PubMed Central

Phylogenetic analyses, based on partial medium- and large-segment sequences, support an ancient evolutionary origin of a genetically distinct hantavirus detected by reverse transcription–PCR in tissues of northern short-tailed shrews (Blarina brevicauda) captured in Minnesota in August 1998. To our knowledge, this is the first evidence of hantaviruses harbored by shrews in the Americas. PMID:18252128

Arai, Satoru; Song, Jin-Won; Sumibcay, Laarni; Bennett, Shannon N.; Nerurkar, Vivek R.; Parmenter, Cheryl; Cook, Joseph A.; Yates, Terry L.

2007-01-01

82

Tactile experience shapes prey-capture behavior in Etruscan shrews  

PubMed Central

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

Anjum, Farzana; Brecht, Michael

2012-01-01

83

Tactile guidance of prey capture in Etruscan shrews  

PubMed Central

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

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

2006-01-01

84

Tripartite genetic subdivisions in the ornate shrew (Sorex ornatus).  

PubMed

We examined cytochrome b sequence variation in 251 ornate shrews (Sorex ornatus) from 20 localities distributed throughout their geographical range. Additionally, vagrant (S. vagrans) and montane (S. monticolus) shrews from four localities were used as outgroups. We found 24 haplotypes in ornate shrews from California (USA) and Baja California (Mexico) that differed by 1-31 substitutions in 392 bp of mitochondrial DNA (mtDNA) sequence. In a subset of individuals, we sequenced 699 bp of cytochrome b to better resolve the phylogeographic relationships of populations. The ornate shrew is phylogeographically structured into three haplotype clades representing southern, central and northern localities. Analysis of allozyme variation reveals a similar pattern of variation. Several other small California vertebrates have a similar tripartite pattern of genetic subdivision. We suggest that topographic barriers and expansion and contraction of wetland habitats in the central valley during Pleistocene glacial cycles account for these patterns of genetic variation. Remarkably, the northern ornate shrew clade is phylogenetically clustered with another species of shrew suggesting that it may be a unique lowland form of the vagrant shrew that evolved in parallel to their southern California counterparts. PMID:11251793

Maldonado, J E; Vilà, C; Wayne, R K

2001-01-01

85

Phylogenetic relationships among Nearctic shrews of the genus Sorex (Insectivora, Soricidae) inferred from combined cytochrome b and inter-SINE fingerprint data using Bayesian analysis.  

PubMed

The field of molecular systematics has relied heavily on mitochondrial DNA (mtDNA) analysis since its inception. Despite the obvious utility of mtDNA, such data inevitably only presents a limited (i.e., single genome) perspective on species evolution. A combination of mitochondrial and nuclear markers is essential for reconstructing more robust phylogenetic trees. To evaluate the utility of one category of nuclear marker (short interspersed elements or SINEs) for resolving phylogenetic relationships, we constructed an inter-SINE fingerprint for nine putative species of the genus Sorex. In addition, we analyzed 1011 nucleotides of the cytochrome b gene. Traditional neighbor-joining and maximum parsimony analyses were applied to the individual cytochrome b and inter-SINE fingerprint data sets, along with Bayesian analysis to the combined data sets. We found inter-SINE fingerprinting to be an effective species level marker; however, we were unable to reconstruct deeper branching patterns within the Sorex genus using these data. The combined data analyzed under a Bayesian analysis showed higher levels of structuring within the Otisorex subgenus, most notably recognizing a monophyletic group consisting of sister-taxa S. palustris and S. monticolus, S. cinereus and S. haydeni, and S. hoyi. An additional noteworthy result was the detection of an historic mitochondrial introgression event between S. monticolus and S. palustris. When combining disparate data sets, we emphasize researcher diligence as certain types of data and processes may overly influence the analysis. However, there is considerable phylogenetic potential stemming from inter-SINE fingerprinting. PMID:17275347

Shafer, Aaron B A; Stewart, Donald T

2007-07-01

86

Phylogenetic relationships among Nearctic shrews of the genus Sorex (Insectivora, Soricidae) inferred from combined cytochrome b and inter-SINE fingerprint data using Bayesian analysis  

Microsoft Academic Search

The field of molecular systematics has relied heavily on mitochondrial DNA (mtDNA) analysis since its inception. Despite the obvious utility of mtDNA, such data inevitably only presents a limited (i.e., single genome) perspective on species evolution. A combination of mitochondrial and nuclear markers is essential for reconstructing more robust phylogenetic trees. To evaluate the utility of one category of nuclear

Aaron B. A. Shafer; Donald T. Stewart

2007-01-01

87

Barrelettes without barrels in the American water shrew.  

PubMed

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

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

2013-01-01

88

Barrelettes without Barrels in the American Water Shrew  

PubMed Central

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

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

2013-01-01

89

DESCRIPTION AND MOLECULAR DIFFERENTIATION OF A NEW STAPHYLOCYSTOIDES (CYCLOPHYLLIDEA: HYMENOLEPIDIDAE) FROM THE DUSKY SHREW SOREX  

E-print Network

: HYMENOLEPIDIDAE) FROM THE DUSKY SHREW SOREX MONTICOLUS IN SOUTHEAST ALASKA Stephen E. Greiman, Vasyl V. Tkach gulyaevi n. sp. is described based on specimens obtained from the dusky shrew Sorex monticolus collected information on shrew helminths is completely lacking. In the summer of 2011 we collected helminths of Sorex

90

Genetic diversity and phylogeography of Seewis virus in the Eurasian common shrew in Finland and Hungary  

Microsoft Academic Search

Recent identification of a newfound hantavirus, designated Seewis virus (SWSV), in the Eurasian common shrew (Sorex araneus), captured in Switzerland, corroborates decades-old reports of hantaviral antigens in this shrew species from Russia. To ascertain the spatial or geographic variation of SWSV, archival liver tissues from 88 Eurasian common shrews, trapped in Finland in 1982 and in Hungary during 1997, 1999

Hae Ji Kang; Satoru Arai; Andrew G Hope; Jin-Won Song; Joseph A Cook; Richard Yanagihara

2009-01-01

91

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

Microsoft Academic Search

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

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

2008-01-01

92

EXTREME MALE-BIASED INFECTIONS OF MASKED SHREWS BY BLADDER NEMATODES  

E-print Network

) intensity in Nova Scotian masked shrews (Sorex cinereus) was related to these variables. We collected, Capillaria, intensity of infection, Liniscus, masked shrews, sex-biased parasitism, Sorex cinereus Numerous] maseri Rausch and Rausch) intensity in host masked shrews (Sorex cinereus Kerr). Although previous

Shutler, Dave

93

Effects of late quaternary climate change on Palearctic shrews.  

PubMed

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 50 000 years 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

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

94

Evolutionary Morphology of the Tenrecoidea (Mammalia) Hindlimb Skeleton  

E-print Network

Evolutionary Morphology of the Tenrecoidea (Mammalia) Hindlimb Skeleton Justine A. Salton1y of traits appear to be phylogenetically constrained, particularly at the upper ankle joint (Salton in the tenrecoid tarsus (Salton and Szalay, 2004) prob- ably extend to differences in the knee and hip joints

Sargis, Eric J.

95

Beitr. Palont., 26:195, Wien 2001 Gulo gulo (Mustelidae, Mammalia) im Jungpleistozn  

E-print Network

Beitr. Paläont., 26:1­95, Wien 2001 Gulo gulo (Mustelidae, Mammalia) im Jungpleistozän Mitteleuropas von Doris D�PPES*) D�PPES, D., 2001. Gulo gulo (Mustelidae, Mammalia) im Jungpleistozän Mitteleuropas. -- Beitr. Paläont., 26:1­95, Wien. Inhalt 1. Biologie des rezenten Gulo gulo (LINNAEUS, 1758

Döppes, Doris

96

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

PubMed Central

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

2013-01-01

97

Circadian rhythms in the short-tailed shrew, Blarina brevicauda.  

PubMed

Circadian rhythms of wheel running and feeding were measured in the short-tailed shrew. Shrews were strongly nocturnal, and their activity rhythms entrained to both long-day (LD 16:8) and short-day (LD 6:18) photocycles. Under conditions of continuous light (LL) or darkness (DD), the activity rhythms free-ran with average periodicities of 25.1 hours and 24.1 hours, respectively. In LL the level of activity was depressed, and in some cases wheel running was completely inhibited. No significant sex differences were observed in the period or amplitude of the monitored circadian rhythms. All shrews fed throughout the day and night; however, unlike in previous reports, ultradian periods of feeding behavior were not found. The results are related to Aschoff's four observations for the effect of light on activity rhythms in nocturnal rodents. PMID:2255728

Antipas, A J; Madison, D M; Ferraro, J S

1990-08-01

98

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

PubMed

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

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

2005-02-01

99

Neuropeptide alterations in the tree shrew hypothalamus during volatile anesthesia  

E-print Network

Neuropeptide alterations in the tree shrew hypothalamus during volatile anesthesia Laetitia perception and brain cognitive state. Prolonged general anesthesia has an impact on many of these processes anesthesia administered accompanying a neurosurgical procedure. Using a predicted-peptide database and hybrid

100

Cortical organization in shrews: evidence from five species.  

PubMed

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

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

1999-07-19

101

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

USGS Publications Warehouse

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.

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

2003-01-01

102

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

PubMed

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

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

1990-10-01

103

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

USGS Publications Warehouse

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.

Blus, L.J.

1978-01-01

104

Muscle senescence in short-lived wild mammals, the soricine shrews Blarina brevicauda and Sorex palustris  

Microsoft Academic Search

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

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

2009-01-01

105

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

PubMed Central

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

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

2009-01-01

106

Journal of East African Natural History 99(1): 18 (2010) SENGI (ELEPHANT-SHREW) OBSERVATIONS FROM  

E-print Network

Journal of East African Natural History 99(1): 1­8 (2010) SENGI (ELEPHANT-SHREW) OBSERVATIONS FROM unique and rare species, including sengis or elephant-shrews (Macroscelidea). Based on recent surveys, distribution, elephant-shrew, Macroscelidea, Rhynchocyon #12;2 S. Andanje, B.R. Agwanda, G.W. Ngaruiya, R. Amin

107

Body Temperature and Behavior of Tree Shrews and Flying Squirrels in a Thermal Gradient  

Microsoft Academic Search

Refinetti, R. Body temperature and behavior of tree shrews and flying squirrels in a thermal gradient. Physiol Behav 63(4) 517–520, 1998. 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

Roberto Refinetti

1998-01-01

108

Bone-marrow mesenchymal stem cell transplantation to treat diabetic nephropathy in tree shrews.  

PubMed

Diabetic nephropathy (DN) is a common microvascular complication of diabetes. We used a new DN model in tree shrews to validate the use of bone-marrow mesenchymal stem cell (BM-MSC) transplantation to treat DN. The DN tree shrew model was established by a high-sugar and high-fat diet and four injections of streptozotocin. 4',6-Diamidino-2-phenylindole labelled BM-MSCs were injected into tree shrews. The DN tree shrew model was successfully established. Blood glucose was significantly increased ( p < 0.01) during the entire experiment. DN tree shrews showed dyslipidemia, insulin resistance and increased 24-h proteinuria. At 21 days after BM-MSC transplantation, glucose and levels of triglycerides, total cholesterol and 24-h urine volume were lower than in tree shrews with DN alone ( p < 0.01) but were still higher than control values ( p < 0.01). Levels of creatinine and urea nitrogen as well as 24-h proteinuria were lower for DN tree shrews with BM-MSCs transplantation than DN alone ( p < 0.05). High-sugar and high-fat diet combined with STZ injection can induce a tree shrew model of DN. BM-MSCs injection can home to damaged kidneys and pancreas, for reduced 24-h proteinuria and improved insulin resistance. PMID:24867093

Pan, Xing-Hua; Yang, Xiao-Yan; Yao, Xiang; Sun, Xiao-Mei; Zhu, Lu; Wang, Jin-Xiang; Pang, Rong-Qing; Cai, Xue-Min; Dai, Jie-Jie; Ruan, Guang-Ping

2014-07-01

109

Muscle aging and oxidative stress in wild-caught shrews Allyson G. Hindle a,  

E-print Network

January 2010 Keywords: Senescence Antioxidant Breath-hold diving Redox Apoptosis Sorex palustris Blarina- 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

Campbell, Kevin L.

110

Seewis virus, a genetically distinct hantavirus in the Eurasian common shrew (Sorex araneus)  

Microsoft Academic Search

More than 20 years ago, hantaviral antigens were reported in tissues of the Eurasian common shrew (Sorex araneus), Eurasian water shrew (Neomys fodiens) and common mole (Talpa europea), suggesting that insectivores, or soricomorphs, might serve as reservoirs of unique hantaviruses. Using RT-PCR, sequences of a genetically distinct hantavirus, designated Seewis virus (SWSV), were amplified from lung tissue of a Eurasian

Jin-Won Song; Se Hun Gu; Shannon N Bennett; Satoru Arai; Maria Puorger; Monika Hilbe; Richard Yanagihara

2007-01-01

111

Extreme Male-Biased Infections of Masked Shrews by Bladder Nematodes  

Microsoft Academic Search

Intensity of parasitic infection (number of parasites per host) can vary by date, and with host age and sex. We tested whether variation in bladder nematode (Liniscus [= Capillaria] maseri) intensity in Nova Scotian masked shrews (Sorex cinereus) was related to these variables. We collected a total of 117 shrews on 8 different sampling occasions between mid-May and mid-August. Univariate

Krystyna M. Cowan; Dave Shutler; Thomas B. Herman; Donald T. Stewart

2007-01-01

112

Population dynamics and foraging of Sorex cinereus (masked shrew) in the boreal forest of eastern Canada  

Microsoft Academic Search

The ecology of shrews is better understood in the boreal forest of Eurasia than in simi- lar regions of North America. In this study, the abundance, reproduction, population structure, and diet of Sorex cinereus (Masked shrew) were analyzed in jack pine plan- tations in the southern boreal forest of eastern Canada over two years. Abundance of S. cinereus showed variations

M. Isabel Bellocq; Sandy M. Smith

113

A climate for speciation: Rapid spatial diversification within the Sorex cinereus complex of shrews  

E-print Network

A climate for speciation: Rapid spatial diversification within the Sorex cinereus complex of shrews in rapid radiations of a number of organisms. Shrews of the Sorex cinereus complex have long challenged successive glacial and interglacial phases each promoted divergence. The Sorex cinereus complex constitutes

114

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

PubMed Central

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

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

2014-01-01

115

Late Pleistocene potential distribution of the North African sengi or elephant-shrew  

E-print Network

Late Pleistocene potential distribution of the North African sengi or elephant-shrew Elephantulus Desert was recently proposed as the agent of vicariant speciation in the North African elephant studies. Key words: sengi, elephant-shrew, vicariant speciation, ecological niche modelling, Last Glacial

116

Population dynamics of the northern short-tailed shrew, Blarina brevicauda: insights from a 25-year  

E-print Network

Population dynamics of the northern short-tailed shrew, Blarina brevicauda: insights from a 25-year demography of the northern short-tailed shrew, Blarina brevicauda (Say, 1823), was studied for 25 years, Blarina brevicauda (Say, 1823), a été étudiée pendant 25 ans dans des habitats de pâturin, de luzerne et d

Oli, Madan K.

117

Seewis virus, a genetically distinct hantavirus in the Eurasian common shrew (Sorex araneus)  

PubMed Central

More than 20 years ago, hantaviral antigens were reported in tissues of the Eurasian common shrew (Sorex araneus), Eurasian water shrew (Neomys fodiens) and common mole (Talpa europea), suggesting that insectivores, or soricomorphs, might serve as reservoirs of unique hantaviruses. Using RT-PCR, sequences of a genetically distinct hantavirus, designated Seewis virus (SWSV), were amplified from lung tissue of a Eurasian common shrew, captured in October 2006 in Graubünden, Switzerland. Pair-wise analysis of the full-length S and partial M and L segments of SWSV indicated approximately 55%–72% similarity with hantaviruses harbored by Murinae, Arvicolinae, Neotominae and Sigmodontinae rodents. Phylogenetically, SWSV grouped with other recently identified shrew-borne hantaviruses. Intensified efforts are underway to clarify the genetic diversity of SWSV throughout the geographic range of the Eurasian common shrew, as well as to determine its relevance to human health. PMID:17967200

Song, Jin-Won; Gu, Se Hun; Bennett, Shannon N; Arai, Satoru; Puorger, Maria; Hilbe, Monika; Yanagihara, Richard

2007-01-01

118

CXC Chemokine CXCL12 and Its Receptor CXCR4 in Tree Shrews (Tupaia belangeri): Structure, Expression and Function  

PubMed Central

Chemokines are small secreted proteins functionally involved in the immune system's regulation of lymphocyte migration across numerous mammalian species. Given its growing popularity in immunological models, we investigated the structure and function of chemokine CXCL12 protein in tree shrews. We found that CXCL12 and its receptor CXCR4 in tree shrew had structural similarities to their homologous human proteins. Phylogenetic analysis supports the view that tree shrew is evolutionarily-close to the primates. Our results also showed that the human recombinant CXCL12 protein directly enhanced the migration of tree shrew's lymphocytes in vitro, while AMD3100 enhanced the mobilization of hematopoietic progenitor cells (HPCs) from bone marrow into peripheral blood in tree shrew in vivo. Collectively, these findings suggested that chemokines in tree shrews may play the same or similar roles as those in humans, and that the tree shrew is a viable animal model for studying human immunological diseases. PMID:24858548

Meng, Shengke; Zhang, Lichao; Wang, Wenxue; Jiang, Zongmin; Yu, Min; Cui, Qinghua; Li, Meizhang

2014-01-01

119

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

PubMed

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

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

2008-01-15

120

Positively selected genes of the Chinese tree shrew (Tupaia belangeri chinensis) locomotion system.  

PubMed

While the recent release of the Chinese tree shrew (Tupaia belangeri chinensis) genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome may facilitate new insights into the applicability of this model. For example, though the tree shrew has a rapid rate of speed and strong jumping ability, there are limited studies on its locomotion ability. In this study we used the available Chinese tree shrew genome information and compared the evolutionary pattern of 407 locomotion system related orthologs among five mammals (human, rhesus monkey, mouse, rat and dog) and the Chinese tree shrew. Our analyses identified 29 genes with significantly high ? (Ka/Ks ratio) values and 48 amino acid sites in 14 genes showed significant evidence of positive selection in the Chinese tree shrew. Some of these positively selected genes, e.g. HOXA6 (homeobox A6) and AVP (arginine vasopressin), play important roles in muscle contraction or skeletal morphogenesis. These results provide important clues in understanding the genetic bases of locomotor adaptation in the Chinese tree shrew. PMID:24866495

Fan, Yu; Yu, Dan-Dan; Yao, Yong-Gang

2014-05-18

121

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

PubMed Central

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

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

2008-01-01

122

Diversification processes in an island radiation of shrews  

E-print Network

al. 1995; Walce 1860). Dynamic geologial and climatic histories have 5 ombined to generate a mtrix of islands in whih the spatil distribution of trrestrial 6 habitas ha ben altred extensively through time (Bird et al. 2005; Hal 1998; Heney 7 1985..., and fossil dates of shrews from the continent are older than those in Eurasia, 20 the group my have originatd in Africa (or perhaps westrn Eurasia) and colonized est 21 Asia reltively recently (Butler 1998; Dubey et al. 2007b, 2008; Hutterer 2005; Storch et...

Esselstyn, Jacob Aaron

2010-04-22

123

Host switch during evolution of a genetically distinct hantavirus in the American shrew mole (Neurotrichus gibbsii)  

PubMed Central

A genetically distinct hantavirus, designated Oxbow virus (OXBV), was detected in tissues of an American shrew mole (Neurotrichus gibbsii), captured in Gresham, Oregon, in September 2003. Pairwise analysis of full-length S- and M- and partial L-segment nucleotide and amino acid sequences of OXBV indicated low sequence similarity with rodent-borne hantaviruses. Phylogenetic analyses using maximum-likelihood and Bayesian methods, and host-parasite evolutionary comparisons, showed that OXBV and Asama virus, a hantavirus recently identified from the Japanese shrew mole (Urotrichus talpoides), were related to soricine shrew-borne hantaviruses from North America and Eurasia, respectively, suggesting parallel evolution associated with cross-species transmission. PMID:19394994

Kang, Hae Ji; Bennett, Shannon N.; Dizney, Laurie; Sumibcay, Laarni; Arai, Satoru; Ruedas, Luis A.; Song, Jin-Won; Yanagihara, Richard

2009-01-01

124

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

PubMed Central

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

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

125

Development of heterodont dentition in house shrew (Suncus murinus).  

PubMed

Mammalian heterodont dentition comprises incisors, canines, premolars, and molars. Although there has been intensive research, the patterning of these specific tooth types has not yet been elucidated. In order for the gene expression data to be linked with tooth type determination, it is first necessary to determine precisely the incisor-, canine-, premolar-, and molar-forming regions in the jaw primordia. To accomplish this, we studied dentition development in the house shrew (Suncus murinus), which has retained all the tooth types, using three-dimensional reconstructions from serial histological sections and the Sonic hedgehog (Shh) expression patterns. Before the appearance of morphological signs of odontogenesis, Shh expression localized to the presumptive tooth-forming regions, in which the mesial and distal expression domains corresponded to the incisor- and premolar-forming regions, respectively. The upper incisor region was found to extend across the boundary between the frontonasal and the maxillary processes. The canine-forming regions later appeared in the intermediate portions of the maxillary and the mandibular processes. The molar-forming regions later appeared distal to the initially demarcated tooth-forming regions by secondary extension of the distal ends. The demarcation visualized by the Shh expression pattern in the jaw primordia of the house shrew probably represents the basic developmental pattern of mammalian heterodont dentition. PMID:18028049

Yamanaka, Atsushi; Yasui, Kinya; Sonomura, Takahiro; Uemura, Masanori

2007-12-01

126

The annular hematoma of the shrew yolk-sac placenta.  

PubMed

The annular hematoma of the shrew, Blarina brevicauda, is a specialized portion of the yolk-sac wall. In this study, we have examined the fine structure of the different cellular components of the anular hematoma. Small pieces of the gestation sacs from seven pregnant shrews were fixed in glutaraldehyde and osmium tetroxide and processed for transmission electron microscopy. In the area of the trophoblastic curtain, the maternal capillary endothelial cells were hypertrophied and syncytial trophoblast surrounded the capillaries. Cellular trophoblast covered part of the luminal surface of the curtain region, whereas masses of apparently degenerating syncytium were present on other areas of the surface. Maternal erythrocytes, released into the uterine lumen from the curtain region, were phagocytized and degraded by the columnar cells of the trophoblastic annulus. No evidence of iron or pigment accumulation was evident in the parietal endodermal cells underlying the annular trophoblast. Parietal endodermal cells were characterized by cuboidal shape, widely dilated intercellular spaces, and cytoplasm containing granular endoplasmic reticulum. Endodermal cells of the visceral yolk-sac accumulated large numbers of electron-dense granules as well as glycogen in their cytoplasm. Hemopoietic areas and vitelline capillaries were found subjacent to the visceral endoderm. The various portions of the yolk-sac wall of Blarina appear to perform complementary functions which are probably important in maternal-fetal iron transfer. PMID:677046

King, B F; Enders, A C; Wimsatt, W A

1978-05-01

127

Factors Influencing the Variation in Capture Rates of Shrews in Southern California, USA  

E-print Network

Introduction Because of various methodological and biological reasons, detailed density estimates of shrews are rare, and usually do not include analysis of the variation in densities (Smallwood and Smith 2001). Since shrews typically die rapidly in traps, their density estimates are usually based on removal trapping. In general, removal methods with shrews have generated higher density estimates than live-trapping (Smallwood and Smith 2001). However, without separate assessment using trap lines to detect shrews immigrating into the trapped area, the effective trapping area cannot be defined (Sarrazin and Bider 1973, Bury and Corn 1987), making it problematic to convert numbers to density. The use of trapping methods other than the preferred pitfall techniques (Smallwood and Smith 2001) usually under- [157] Acta Theriologica 48 (2): 157--166, 2003. PL ISSN 0001--7051 * Present address: Finnish Forest Research Institute, P.O. Box 18, FIN--01301, Vantaa, Finland, e-amil: juha.laakkon

Juha Laakkonen; Robert N. Fisher; Ted J. Case; Laakkonen J; Fisher R. N

2003-01-01

128

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

E-print Network

of echolocation, sonar, or electroreception was inves- tigated by testing for ultrasonic and audible calls above for echolocation, sonar, or electroreception. However, water shrews vigorously attacked brief sudden water

Campbell, Kevin L.

129

Genetic diversity and phylogeography of Seewis virus in the Eurasian common shrew in Finland and Hungary  

PubMed Central

Recent identification of a newfound hantavirus, designated Seewis virus (SWSV), in the Eurasian common shrew (Sorex araneus), captured in Switzerland, corroborates decades-old reports of hantaviral antigens in this shrew species from Russia. To ascertain the spatial or geographic variation of SWSV, archival liver tissues from 88 Eurasian common shrews, trapped in Finland in 1982 and in Hungary during 1997, 1999 and 2000, were analyzed for hantavirus RNAs by reverse transcription-polymerase chain reaction. SWSV RNAs were detected in 12 of 22 (54.5%) and 13 of 66 (19.7%) Eurasian common shrews from Finland and Hungary, respectively. Phylogenetic analyses of S- and L-segment sequences of SWSV strains, using maximum likelihood and Bayesian methods, revealed geographic-specific genetic variation, similar to the phylogeography of rodent-borne hantaviruses, suggesting long-standing hantavirus-host co-evolutionary adaptation. PMID:19930716

2009-01-01

130

Ticks and fleas of shrews in Appalachian Georgia and North Carolina.  

PubMed

Ticks (Acari: Ixodidae) and fleas (Insecta: Siphonaptera) were recovered from 8 smoky shrews, Sorex fumeus Miller, and 9 northern short-tailed shrews, Blarina brevicauda (Say), trapped at elevations of 720-1,310 m in Macon and Jackson counties in western North Carolina and Union County in northern Georgia from April 1994 to August 1995. The ticks Ixodes angustus Neumann and Ixodes woodi Bishopp, and the flea Corrodopsylla curvata (Rothschild), were recovered from smoky shrews. The same 2 tick species, in addition to the fleas, Ctenophthalmus pseudagyrtes Baker and Doratopsylla blarinae Fox, were recovered from northern short-tailed shrews. New state records for I. angustus from Georgia and I. woodi from North Carolina are established. PMID:8691385

McCay, T S; Durden, L A

1996-08-01

131

THE OCCURRENCE OF A SPOROZOAN IN THE MYOCARDIUM OF SHORT-TAILED SHREW (Blarina brevicauda)  

Microsoft Academic Search

A cyst was observed in the cardiac musculature of a short-tailed shrew (B\\/anna brevicauda) during a survey on the helminth fauna of the species in Connecticut. Histologically this organism resembled a species of Sarcocystis.

J. E. HUFFMAN; D. E. ROSCOE

132

Seewis Virus: Phylogeography of a Shrew-Borne Hantavirus in Siberia, Russia  

PubMed Central

Abstract Background Hantaviral antigens were originally reported more than 20 years ago in tissues of the Eurasian common shrew (Sorex araneus), captured in European and Siberian Russia. The recent discovery of Seewis virus (SWSV) in this soricid species in Switzerland provided an opportunity to investigate its genetic diversity and geographic distribution in Russia. Methods Lung tissues from 45 Eurasian common shrews, 4 Laxmann's shrews (Sorex caecutiens), 3 Siberian large-toothed shrews (Sorex daphaenodon), 9 pygmy shrews (Sorex minutus), 28 tundra shrews (Sorex tundrensis), and 6 Siberian shrews (Crocidura sibirica), captured in 11 localities in Western and Eastern Siberia during June 2007 to September 2008, were analyzed for hantavirus RNA by reverse transcription–polymerase chain reaction. Results Hantavirus L and S segment sequences, detected in 11 S. araneus, 2 S. tundrensis, and 2 S. daphaenodon, were closely related to SWSV, differing from the prototype mp70 strain by 16.3–20.2% at the nucleotide level and 1.4–1.7% at the amino acid level. Alignment and comparison of nucleotide and amino acid sequences showed an intrastrain difference of 0–11.0% and 0% for the L segment and 0.2–8.5% and 0% for the S segment, respectively. Phylogenetic analysis, using neighbor-joining, maximum-likelihood, and Bayesian methods, showed geographic-specific clustering of SWSV strains in Western and Eastern Siberia. Conclusions This is the first definitive report of shrew-borne hantaviruses in Siberia, and demonstrates the impressive distribution of SWSV among phylogenetically related Sorex species. Coevolution and local adaptation of SWSV genetic variants in specific chromosomal races of S. araneus may account for their geographic distribution. PMID:20426688

Abramov, Sergey A.; Gutorov, Valery V.; Dupal, Tamara A.; Krivopalov, Anton V.; Panov, Victor V.; Danchinova, Galina A.; Vinogradov, Vladislav V.; Luchnikova, Ekaterina M.; Hay, John; Kang, Hae Ji; Yanagihara, Richard

2010-01-01

133

Prey size, prey nutrition, and food handling by shrews of different body sizes  

Microsoft Academic Search

We tested some predictions relating metabolic constraints of foraging behavior and prey selection by comparing food handling and utilization in four sympatric shrew species: Sorex minutus (mean body mass = 3.0 g), S. araneus (8.0 g), Neomys anomalus (10.0 g), and N. fodiens (14.4 g). Live fly larvae, mealworm larvae, and aquatic arthropods were offered to shrews as small prey

Leszek Rychlik

2002-01-01

134

Patterns of Sequence Variation in the Mitochondrial D-Loop Region of Shrews  

Microsoft Academic Search

Direct sequencing of the mitochondrial displacement loop (D-loop) of shrews (genus Sorex) for the region between the tRNA pro and the conserved sequence block-F revealed variable numbers of 79-bp tandem repeats. These repeats were found in all 19 individuals sequenced, representing three subspecies and one closely related species of the masked shrew group (Sorex cineretrs cinereus, S. c. miscix, S.

Donald T. Stewart; Allan J. Baker

1994-01-01

135

New infectious spirochete isolated from short-tailed shrews and white-footed mice.  

PubMed Central

A spirochete with two periplasmic flagella was isolated from the blood or tissues of spleens and kidneys from short-tailed shrews (Blarina brevicauda) and white-footed mice (Peromyscus leucopus) in Connecticut and Minnesota. After inoculation, the shrew-mouse spirochete infected Swiss mice and Syrian hamsters. This spirochete is morphologically and serologically distinct from the species of Treponema, Borrelia, Leptospira, and Spirochaeta examined. Images PMID:3305565

Anderson, J F; Johnson, R C; Magnarelli, L A; Hyde, F W; Andreadis, T G

1987-01-01

136

Growth, development and maintenance of American water shrews (Sorex palustris) in captivity  

Microsoft Academic Search

This paper documents a cost-effective method for the long-term housing and main- tenance of water shrews. Wild-caught American water shrews (Sorex palustris) were success- fully maintained in this set up for up to 2 years, suggesting a maximum lifespan of 28 months for this species in captivity. In addition, we describe the postnatal growth and development of S. palustris based

Roman W. Gusztak; Kevin L. Campbell

2004-01-01

137

New infectious spirochete isolated from short-tailed shrews and white-footed mice.  

PubMed

A spirochete with two periplasmic flagella was isolated from the blood or tissues of spleens and kidneys from short-tailed shrews (Blarina brevicauda) and white-footed mice (Peromyscus leucopus) in Connecticut and Minnesota. After inoculation, the shrew-mouse spirochete infected Swiss mice and Syrian hamsters. This spirochete is morphologically and serologically distinct from the species of Treponema, Borrelia, Leptospira, and Spirochaeta examined. PMID:3305565

Anderson, J F; Johnson, R C; Magnarelli, L A; Hyde, F W; Andreadis, T G

1987-08-01

138

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

PubMed

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

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

139

Chemoarchitecture of layer 4 isocortex in the American water shrew (Sorex palustris).  

PubMed

We examined the chemoarchitecture of layer 4 isocortex and the number of myelinated nerve fibers of selected cranial nerves in the American water shrew (Sorex palustris). This study took advantage of the opportunity to examine juvenile brain tissue, which often reveals the most distinctive cortical modules related to different sensory representations. Flattened cortical sections were processed for the metabolic enzyme cytochrome oxidase, revealing a number of modules and septa. Subdivisions related to sensory representations were tentatively identified by performing microelectrode recordings in a single adult shrew in this study, combined with microelectrode recordings and anatomical findings from a previous investigation. Taken together, these results suggest that characteristic chemoarchitectonic borders in the shrew neocortex can be used to delineate and quantify cortical areas. The most obvious subdivisions in the water shrew include a relatively small primary visual cortex which responded to visual stimuli, a larger representation of vibrissae in the primary somatosensory cortex, and a prominent representation of oral structures apparent in the more rostral-lateral cortex. A presumptive auditory area was located in the far caudal cortex. These findings for the cortex are consistent with counts from optic, auditory and trigeminal nerves, suggesting that somatosensory inputs dominate the shrew's senses whereas visual and auditory inputs play a small role in navigation and in finding prey. More generally, we find that shrews share unusual features of cortical organization with moles, supporting their close taxonomic relationship. PMID:21985842

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

2011-01-01

140

Molecular phylogeny of a newfound hantavirus in the Japanese shrew mole (Urotrichus talpoides)  

PubMed Central

Recent molecular evidence of genetically distinct hantaviruses in shrews, captured in widely separated geographical regions, corroborates decades-old reports of hantavirus antigens in shrew tissues. Apart from challenging the conventional view that rodents are the principal reservoir hosts, the recently identified soricid-borne hantaviruses raise the possibility that other soricomorphs, notably talpids, similarly harbor hantaviruses. In analyzing RNA extracts from lung tissues of the Japanese shrew mole (Urotrichus talpoides), captured in Japan between February and April 2008, a hantavirus genome, designated Asama virus (ASAV), was detected by RT-PCR. Pairwise alignment and comparison of the S-, M-, and L-segment nucleotide and amino acid sequences indicated that ASAV was genetically more similar to hantaviruses harbored by shrews than by rodents. However, the predicted secondary structure of the ASAV nucleocapsid protein was similar to that of rodent- and shrew-borne hantaviruses, exhibiting the same coiled-coil helix at the amino terminus. Phylogenetic analyses, using the maximum-likelihood method and other algorithms, consistently placed ASAV with recently identified soricine shrew-borne hantaviruses, suggesting a possible host-switching event in the distant past. The discovery of a mole-borne hantavirus enlarges our concepts about the complex evolutionary history of hantaviruses. PMID:18854415

Arai, Satoru; Ohdachi, Satoshi D.; Asakawa, Mitsuhiko; Kang, Hae Ji; Mocz, Gabor; Arikawa, Jiro; Okabe, Nobuhiko; Yanagihara, Richard

2008-01-01

141

Livestock grazing intensity affects abundance of Common shrews (Sorex araneus) in two meadows in Denmark  

PubMed Central

Background Current nature conservation in semi-natural grasslands often includes grazing and hay cutting, as well as the abandonment of draining. Semi-natural grassland and in particular meadows constitute important habitat type for a large number of animal species in today's fragmented and intensively cultivated landscape of Europe. Here we focus on the population characteristics of Common shrews Sorex araneus in relation to livestock grazing intensity in two wet meadows in western Denmark. Results High grazing intensity had a significant negative effect on Common shrew number compared to low grazing intensity and no grazing. Common shrew abundance was generally, but not significantly, higher on the low grazing intensity plots than on the ungrazed controls. No differences in body mass, sex ratio, or reproductive output between Common shrew individuals from the various grazing treatments were found. Conclusion No negative effects of low intensity grazing on Common shrew abundance were found compared to the ungrazed control. Low intensity grazing thus seems a suitable management regime for Common shrews, when grazing is needed as part of the meadow management scheme. High intensity grazing on the other hand is not a suitable management tool. PMID:19152713

Schmidt, Niels M; Olsen, Henrik; Leirs, Herwig

2009-01-01

142

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

PubMed Central

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

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

2012-01-01

143

Patterns of sequence variation in the mitochondrial D-loop region of shrews.  

PubMed

Direct sequencing of the mitochondrial displacement loop (D-loop) of shrews (genus Sorex) for the region between the tRNA(Pro) and the conserved sequence block-F revealed variable numbers of 79-bp tandem repeats. These repeats were found in all 19 individuals sequenced, representing three subspecies and one closely related species of the masked shrew group (Sorex cinereus cinereus, S. c. miscix, S. c. acadicus, and S. haydeni) and an outgroup, the pygmy shrew (S. hoyi). Each specimen also possessed an adjacent 76-bp imperfect copy of the tandem repeats. One individual was heteroplasmic for length variants consisting of five and seven copies of the 79-bp tandem repeat. The sequence of the repeats is conducive to the formation of secondary structure. A termination-associated sequence is present in each of the repeats and in a unique sequence region 5' to the tandem array as well. Mean genetic distance between the masked shrew taxa and the pygmy shrew was calculated separately for the unique sequence region, one of the tandem repeats, the imperfect repeat, and these three regions combined. The unique sequence region evolved more rapidly than the tandem repeats or the imperfect repeat. The small genetic distance between pairs of tandem repeats within an individual is consistent with a model of concerted evolution. Repeats are apparently duplicated and lost at a high rate, which tends to homogenize the tandem array. The rate of D-loop sequence divergence between the masked and pygmy shrews is estimated to be 15%-20%/Myr, the highest rate observed in D-loops of mammals. Rapid sequence evolution in shrews may be due either to their high metabolic rate and short generation time or to the presence of variable numbers of tandem repeats. PMID:8121290

Stewart, D T; Baker, A J

1994-01-01

144

NEW SKULLS OF KOLPOCHOERUS PHACOCHOEROIDES (SUIDAE, MAMMALIA) FROM THE LATE PLIOCENE OF AHL AL OUGHLAM,  

E-print Network

1 NEW SKULLS OF KOLPOCHOERUS PHACOCHOEROIDES (SUIDAE, MAMMALIA) FROM THE LATE PLIOCENE OF AHL AL of contents INTRODUCTION 2 SYSTEMATIC PALEONTOLOGY-Genus Kolpochoerus 3 Currently recognised species 4 Sexual Sciences de l'Archéologie et du Patrimoine of Rabat. It is the richest fossil locality of the North African

Boyer, Edmond

145

Phylogeny of the Procyonidae (Mammalia: Carnivora): Molecules, morphology and the Great American Interchange  

Microsoft Academic Search

The Procyonidae (Mammalia: Carnivora) have played a central role in resolving the controversial systematics of the giant and red pandas, but phylogenetic relationships of species within the family itself have received much less attention. Cladistic analyses of morphological characters conducted during the last two decades have resulted in topologies that group ecologically and morphologically similar taxa together. Specifically, the highly

Klaus-Peter Koepfli; Matthew E. Gompper; Eduardo Eizirik; Cheuk-Chung Ho; Leif Linden; Jesus E. Maldonado; Robert K. Wayne

2007-01-01

146

Topografia do cone medular no ratão-do-banhado ( Myocastor coypus Molina, 1782 - Rodentia: Mammalia)  

Microsoft Academic Search

Topography of the medullar cone in nutria (Myocastor coypus Molina, 1782 - Rodentia: Mammalia). Aiming to investigate the topography of the medullar cone, ten adult nutria (Myocastor coypus), eight male and two female, were previously fixed in 10% aqueous formalin solution, maintained in similar solution and dissected. After the dissection the following data were noted: a) the medullar cone apex

Gilberto Valente Machado; Josy Alvarenga Cal; Arlei José Birck

147

Un Ailurinae (Mammalia, Carnivora, Ailuridae) dans le Miocène moyen de Four (Isère, France)  

Microsoft Academic Search

An Ailurinae (Mammalia, Carnivora, Ailuridae) in the middle Miocene of Four (Isère, France). An upper molar of an Ailurinae is described from the middle Miocene of Four, a locality near La Grive-Saint-Alban (Isère, France). This new miocene tooth is different from Magerictis imperialensis Ginsburg, Morales, Soria & Herraez, 1997 from the middle Miocene of Madrid (Spain). Its overall qua- drangular

Léonard GINSBURG; Olivier MARIDET; Pierre MEIN

148

Physical and morphological aspects of the eye of the manatee trichechus inunguis natterer 1883: (Sirenia: Mammalia)  

Microsoft Academic Search

The eyes and aspects of vision of the Amazonian manatee Trichechus inunguis NATTERER 1883: (Sirenia: mammalia) have been examined in five animals, in relation to previous findings for sirenians. This paper presents a review of previous findings confirming those upon gross ocular anatomy, retinal histology and ocular refraction. The confirmation of a primarily rod retina, high receptor: ganglion cell ratio

David Piggins; W. R. A. Muntz; Robin C. Best

1983-01-01

149

Chronic Psychosocial Stress Causes Apical Dendritic Atrophy of Hippocampal CA3 Pyramidal Neurons in Subordinate Tree Shrews  

Microsoft Academic Search

We have shown previously that repeated laboratory restraint stress or daily corticosterone administration affects the struc- ture of CA3 hippocampal neurons in rats. In the present study, we investigated the effect of repeated daily psychosocial stress on the structure of hippocampal CA3 pyramidal neurons in male tree shrews (Tupaia belangeri). Male tree shrews develop social hierarchies in which subordinates show

Ana Maria Magarinos; Bruce S. McEwen; Gabriele Flugge; Eberhard Fuchs

1996-01-01

150

LONGEVITY OF THE NORTHERN SHORT-TAIL SHREW (BLARINA BREVICAUDA) AT RICE CREEK FIELD STATION, SUNY OSWEGO  

Microsoft Academic Search

Long-term longitudinal studies can provide information on habitat quality over time. The Short-tailed shrew (Blarina brevicauda) is carnivorous, abundant in most habitats and lives 18 months or less. Ageing criteria based on weight or reproductive condition provide unreliable results since shrews are nearly adult weight at emergence from the nest and can begin reproduction shortly thereafter. The only reliable ageing

Sara Ressing

151

Drug Target Mining and Analysis of the Chinese Tree Shrew for Pharmacological Testing  

PubMed Central

The discovery of new drugs requires the development of improved animal models for drug testing. The Chinese tree shrew is considered to be a realistic candidate model. To assess the potential of the Chinese tree shrew for pharmacological testing, we performed drug target prediction and analysis on genomic and transcriptomic scales. Using our pipeline, 3,482 proteins were predicted to be drug targets. Of these predicted targets, 446 and 1,049 proteins with the highest rank and total scores, respectively, included homologs of targets for cancer chemotherapy, depression, age-related decline and cardiovascular disease. Based on comparative analyses, more than half of drug target proteins identified from the tree shrew genome were shown to be higher similarity to human targets than in the mouse. Target validation also demonstrated that the constitutive expression of the proteinase-activated receptors of tree shrew platelets is similar to that of human platelets but differs from that of mouse platelets. We developed an effective pipeline and search strategy for drug target prediction and the evaluation of model-based target identification for drug testing. This work provides useful information for future studies of the Chinese tree shrew as a source of novel targets for drug discovery research. PMID:25105297

Liu, Jie; Lee, Wen-hui; Zhang, Yun

2014-01-01

152

Attempted isolation of Blastomyces dermatitidis from native shrews in northern Wisconsin, USA.  

PubMed

The precise ecological niche of Blastomyces dermatitidis is unknown. The related dimorphic fungus, Paracoccidioides brasiliensis, has been isolated from South American ground-dwelling insectivorous armadillos. We attempted to isolate Blastomyces from shrews, North American ground-dwelling insectivores that have been shown to harbor Histoplasma capsulatum in endemic areas. Forty-seven masked shrews (Sorex cinereus) and 13 northern short-tailed shrews (Blarina brevicauda) were collected in endemic areas of northern Wisconsin and Michigan using pitfall traps. Specimens were collected between 1998 and summer 2002, stored frozen, then necropsied. Cultures of nasopharynx, lungs, liver, spleen and large and small bowel were placed on yeast extract phosphate agar with one or two drops of ammonium hydroxide. Cultures for Blastomyces were negative from all 60 shrews and two deer mice (Peromyscus maniculatus) and three southern red-backed voles (Clethrionomys gapperi), which were trapped inadvertently. Histological examination of 36 of these specimens revealed no Blastomyces yeast forms. Northern Wisconsin shrews do not appear to be carriers of B. dermatitidis. PMID:16178369

Baumgardner, Dennis J; Summerbell, Richard; Krajden, Sigmund; Alexopoulou, Iakovina; Agrawal, Bobby; Bergeson, Mitch; Fuksa, Milan; Bemis, Christina; Baumgardner, Mark A

2005-08-01

153

unknown title  

E-print Network

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

S. A. Sonsthagen; G. K. Sage; M. Fowler; A. G. Hope; J. A. Cook; S. L. Talbot; Conservation Genet Resour; Conservation Genet Resour

2012-01-01

154

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

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

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

1994-08-01

155

Muscle senescence in short-lived wild mammals, the soricine shrews Blarina brevicauda and Sorex palustris.  

PubMed

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 (H(0): 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: approximately 50%; B. brevicauda: approximately 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 ( approximately 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

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

2009-06-01

156

Ultrastructural localization of tyrosine hydroxylase in tree shrew nucleus accumbens core and shell.  

PubMed

Many behavioral, physiological, and anatomical studies utilize animal models to investigate human striatal pathologies. Although commonly used, rodent striatum may not present the optimal animal model for certain studies due to a lesser morphological complexity than that of non-human primates, which are increasingly restricted in research. As an alternative, the tree shrew could provide a beneficial animal model for studies of the striatum. The gross morphology of the tree shrew striatum resembles that of primates, with separation of the caudate and putamen by the internal capsule. The neurochemical anatomy of the ventral striatum, specifically the nucleus accumbens, has never been examined. This major region of the limbic system plays a role in normal physiological functioning and is also an area of interest for human striatal disorders. The current study uses immunohistochemistry of calbindin and tyrosine hydroxylase (TH) to determine the ultrastructural organization of the nucleus accumbens core and shell of the tree shrew (Tupaia glis belangeri). Stereology was used to quantify the ultrastructural localization of TH, which displays weaker immunoreactivity in the core and denser immunoreactivity in the shell. In both regions, synapses with TH-immunoreactive axon terminals were primarily symmetric and showed no preference for targeting dendrites versus dendritic spines. The results were compared to previous ultrastructural studies of TH and dopamine in rat and monkey nucleus accumbens. Tree shrews and monkeys show no preference for the postsynaptic target in the shell, in contrast to rats which show a preference for synapsing with dendrites. Tree shrews have a ratio of asymmetric to symmetric synapses formed by TH-immunoreactive terminals that is intermediate between rats and monkeys. The findings from this study support the tree shrew as an alternative model for studies of human striatal pathologies. PMID:24769226

McCollum, L A; Roberts, R C

2014-06-20

157

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

PubMed Central

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 Côte 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

2011-01-01

158

The morphogenesis of the arteries of the pelvic extremity. A comparative study of mammals with special reference to the tree shrew Tupaia belangeri (Tupaiidae, Scandentia, Mammalia).  

PubMed

The ontogeny of the arteries of the pelvic extremity of Tupaia belangeri was investigated by light microscopy on the basis of serial sections of 30 embryos, dating from day 17 to day 42 post-copulation. In Tupaia, the gestational period takes approximately 43 days. Additionally, a 3-D reconstruction of the pelvic region and the right leg of a 22-day embryo was prepared. The arteries of an adult Tupaia were studied on the basis of a corrosion cast. The results were compared with the ontogeny of the arterial system of other mammals. In the 17-day embryo, the anlage of the pelvic extremity is penetrated by a capillary plexus. In the 18-day embryo, the a. ischiadica reaches the pelvic limb bud, representing the primary axial artery. On day 19, its r. perforans tarsi extends from the plantar to the dorsal aspect of the foot plate. The a. ischiadica is the main artery of the leg until the stage of the 22-day embryo. Afterwards, the peripheral arteries supplied by it are taken over by the a. iliaca externa and its extension, the a. femoralis. The a. iliaca externa springs from the a. iliaca communis in the 19-day embryo. From day 21 to day 22, the capillary plexus, which is nourished by the a. femoralis, closely approaches the a. ischiadica, and finally, a connecting branch joins the a. ischiadica. The a. ischiadica is then reduced to the a. glutea caudalis, and the aa. femoralis, poplitea profunda (at the cranial aspect of the m. popliteus), and interossea become the main arteries of the pelvic extremity. The a. poplitea superficialis, lying at the caudal aspect of the m. popliteus, and its continuation in the crural region, the a. peronea, develop until the 25-day embryo. The a. peronea gives rise to an r. perforans which penetrates the membrana interossea towards the dorsum of the foot. As a result of a shift of the origin of the a. iliaca externa in the proximal direction, the length of the a. iliaca communis gradually decreases until, on day 24, the a. iliaca externa springs directly from the lateral wall of the aorta. In the 20-day embryo, the a. iliaca externa gives rise to an a. circumflexa ilium profunda towards the lateral pelvic wall, and in 23-day embryos, to the a. profunda femoris. The main branches of the a. profunda femoris develop until day 24. At the same time, the aa. circumflexa femoris lateralis and nutricia ossis femoris arise from the a. femoralis. The a. saphena, which is already recognizable in the 23-day embryo, gives rise to the a. genus descendens, and as an a. plantaris medialis, to four aa. digitales plantares communes (I-IV) at the planta pedis. The development of the a. tibialis cranialis on day 25 takes place independently and without any topographic relation to the a. saphena, which functionally replaces the a. tibialis cranialis in some other mammals. In the 26-day embryo, the aa. peronea and tibialis cranialis extend to the dorsum of the foot where they continue as the aa. dorsales pedis profunda and superficialis. The fourth main artery of the lower leg, the a. caudalis femoris, which is first observed in the 20-day embryo, reaches the lateral aspect of the foot on day 24. Its r. calcaneus runs to the planta pedis. In 30-day embryos, the aa. digitales plantares propriae have differentiated. The corresponding dorsal arteries and the superficial plantar vascular are develop until day 35, so that all important arteries of the pelvic extremity, which are seen in the corrosion cast of the adult, are recognizable. Among the embryos and the adult Tupaia studied, individual variation is minimal. The developmental stage at which the arteries of the leg acquired a secondary vascular wall was ascertained. Only a vessel with a primary vascular wall can dissolve into a capillary plexus later on (e.g., a. interossea). In contrast, the course of an artery which has acquired a secondary vascular wall is determined, because modifications of the course of a vessel often need a capillary plexus as an intermediate st PMID:9816724

Funke, C; Kuhn, H J

1998-01-01

159

New Views on Tree Shrews: The Role of Tupaiids in Primate Supraordinal Relationships  

E-print Network

that these fossils should not be allocated to a new genus be- cause they are virtually identical to Tupaia.12- ing Tupaia was discovered in Pliocene sediments.29 The Miocene fossils were attributed to a new taxonARTICLES New Views on Tree Shrews: The Role of Tupaiids in Primate Supraordinal Relationships ERIC

Sargis, Eric J.

160

Prey size selection and competition in the common shrew ( Sorex araneus L.)  

Microsoft Academic Search

1.We examine the idea that predators may sometimes use a rule of thumb (in this case prey size) to estimate relative prey profitability for optimizing diet selection. We provided adult common shrews with a choice between large and small pieces of mealworm, where large pieces were less profitable than small, because of handling time characteristics.2.The tendency for animals to prefer

C. J. Barnard; C. A. J. Brown

1981-01-01

161

Synaptic Organization of Connections between the Temporal Cortex and Pulvinar Nucleus of the Tree Shrew  

Microsoft Academic Search

We examined the synaptic organization of reciprocal connections between the temporal cortex and the dorsal (Pd) and central (Pc) subdivisions of the tree shrew pulvinar nucleus, regions innervated by the medial and lateral superior colliculus, respectively. Both Pd and Pc subdivisions project topographically to 2 separate regions of the temporal cortex; small injections of anterograde tracers placed in either Pd

Ranida D. Chomsung; Haiyang Wei; Jonathan D. Day-Brown; Heywood M. Petry; Martha E. Bickford

2010-01-01

162

Mitochondrial DNA variation in water shrews (Sorex palustris, Sorex bendirii) from western  

E-print Network

Mitochondrial DNA variation in water shrews (Sorex palustris, Sorex bendirii) from western North of Sorex palustris Richardson, 1828 and 6 specimens of Sorex bendirii (Merriam, 1884) from 20 locations the Coastal and the Cordilleran clades was 3.1%. Sorex palustris brooksi, a subspecies endemic to Vancouver

Baker, Robert J.

163

The neurobiology and behavior of the American water shrew (Sorex palustris).  

PubMed

American water shrews (Sorex palustris) are aggressive predators that dive into streams and ponds to find prey at night. They do not use eyesight for capturing fish or for discriminating shapes. Instead they make use of vibrissae to detect and attack water movements generated by active prey and to detect the form of stationary prey. Tactile investigations are supplemented with underwater sniffing. This remarkable behavior consists of exhalation of air bubbles that spread onto objects and are then re-inhaled. Recordings for ultrasound both above and below water provide no evidence for echolocation or sonar, and presentation of electric fields and anatomical investigations provide no evidence for electroreception. Counts of myelinated fibers show by far the largest volume of sensory information comes from the trigeminal nerve compared to optic and cochlear nerves. This is in turn reflected in the organization of the water shrew's neocortex, which contains two large somatosensory areas and much smaller visual and auditory areas. The shrew's small brain with few cortical areas may allow exceptional speed in processing sensory information and producing motor output. Water shrews can accurately attack the source of a water disturbance in only 50 ms, perhaps outpacing any other mammalian predator. PMID:23397460

Catania, Kenneth C

2013-06-01

164

Evolutionary biogeography of water shrews ( Neomys spp.) in the western Palaearctic Region  

Microsoft Academic Search

We studied the morphology, DNA sequence, and Recent and Pleistocene distributions of three species of the water shrew genus Neomys (N. fodiens, N. anomalus, and N. teres) represented by samples from the Balkans and Asia Minor. Adaptations to semi-aquatic life (large body size, fringes of stiff hairs bordering the hind foot, and a tail keel) were most developed in N.

B. Krystufek; A. Davison; H. I. Griffiths

2000-01-01

165

Chemoarchitecture of Layer 4 Isocortex in the American Water Shrew (Sorex palustris)  

Microsoft Academic Search

We examined the chemoarchitecture of layer 4 isocortex and the number of myelinated nerve fibers of selected cranial nerves in the American water shrew (Sorex palustris). This study took advantage of the opportunity to examine juvenile brain tissue, which often reveals the most distinctive cortical modules related to different sensory representations. Flattened cortical sections were processed for the metabolic enzyme

Duncan B. Leitch; Danielle Gauthier; Diana K. Sarko; Kenneth C. Catania

2011-01-01

166

Distribution, Habitat Use, and Identification of Masked Shrews, Sorex cinereus and Sorex haydeni, in Minnesota  

Microsoft Academic Search

A BSTRACT.—Several studies support specific status for the prairie form of Sorex cinereus, designated as Sorex haydeni. Evidence for introgression between these species has been found in Alberta despite significant sequence differences (>15%) in mitochondrial DNA. We identified to species 94 masked shrews using mtDNA and morphological criteria to assess the distribution of these two species in Minnesota and to

ANJA K. BRUNET; ROBERT M. ZINK; KRISTIN M. KRAMER

167

Molecular phylogeny of long-tailed shrews (genus Sorex) from México and Guatemala  

E-print Network

We present a molecular phylogeny of North American species of long-tailed shrews of the genus Sorex. Our focus is on Mexican and Guatemalan species to begin understanding their evolutionary relationships and to test the validity of nominal species. Seventy-seven sequences of the mitochondrial cytochrome b gene were analyzed, including 19 specimens representing nine Mexican and one Guatemalan species. Phylogenetic analyses using parsimony, maximum likelihood and Bayesian approaches revealed two major clades of North American species, all within the subgenus Otisorex. The first major clade includes S. trowbridgii and southern species (S. macrodon from Oaxaca; S. veraecrucis from Nuevo León, Michoacán, Chiapas, S. saussurei from Jalisco and Guatemala; S. veraepacis from Guerrero and Guatemala). Relatively deep branches among taxa characterize this clade and suggest that their early divergence from other North American shrews was soon after arrival of the ancestral stock from the Beringian region. The other major clade includes all other North American species of Sorex we examined, with two Mexican species, S. milleri and S. emarginatus, grouped in a subclade with the S. cinereus complex. Sorex veraecrucis is not, however, a monophyletic taxon because specimens of this nominal species were included in both the major clades. The Isthmus of Tehuantepec has likely played a role as a biogeographic barrier in the evolutionary history of Mexican shrews. This study of mitochondrial variation in southern North American shrews of the genus Sorex indicates there is substantial, previously

Martha Esteva; Fernando A. Cervantes; Sara V. Brant; Joseph A. Cook

168

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

Microsoft Academic Search

We trapped shrews at six 9.3 ha plots from which logs 210 cm diameter (coarse woody debris; CWD) had been manually removed and six control plots in managed loblolly pine (Pinus taeda) forests of the southeastern coastal plain, USA. Trapping was conducted seasonally between antumn 1997 and summer 2001. Capture rates of Cryptotis'parvu were lower at plots from which CWD

Timothy S. MCC

169

Olfactory mucosa ultrastructure in the short-tailed shrews, Blarina brevicauda and Blarina carolinensis.  

PubMed

The olfactory mucosae of the northern short-tailed shrew, Blarina brevicauda, and the southern short-tailed shrew, Blarina carolinensis, were examined by light and electron microscopy. A well-developed olfactory epithelium was observed that included all of the cells necessary to provide for a sensitive olfactory system, suggesting that olfaction plays a major role in the behavior of these animals. There were no significant differences between the olfactory mucosae of these two species. The general features of the olfactory epithelium in these shrews were similar to those reported for several other macrosmatic mammals. A new type of supporting cell, called the light supporting cell, was observed in these shrews. The light supporting cell cytoplasm exhibited very little staining by light microscopy and had low electron density by transmission electron microscopy compared to that of the more common dark supporting cell. The light supporting cell had a convex apical surface with microvilli and lacked the large amounts of smooth endoplasmic reticulum (SER) typical of the apical cytoplasm of the dark supporting cell. In the lamina propria of the mucosa, the Bowman's glands consisted of two cell types, one with electron-lucent, alcian blue-positive granules, and the other with electron-dense PAS-positive granules. The cell with electron-lucent granules contained large amounts of SER and small clumps of rough ER. The cells with electron-dense granules had large amounts of RER and little SER. PMID:12221510

Byrum, L J; Carson, K A; Rose, R K

2001-12-01

170

Ultrastructure of the stomach of the small short-tailed shrew, Blarina brevicauda c.  

PubMed

The normal gastric ultrastructure has been characterized for the small short-tailed shrew, Blarina brevicauda c., which is a primitive eutherian and one of the smallest living mammals with extraordinarily high metabolic rate. In general the cell types present and cytologic character of gastric mucosal, submucosal, and muscularis cells were similar to that reported for other more advanced small mammalian species. Chief cells, endocrine cells, and lamina proprial elements were morphologically identical to their counterpart in rats, ferrets and other small carnivores. Distinctive cytologic features in this species of shrew included the scanty monolayer or small number of mucous granules in the simple columnar surface epithelial cells of the mucosa, and the thin elongated shape of their microvilli. Dense bodies were absent in the parietal cell mitochondria of the shrew, though usually abundant in other mammalian parietal cells. Our data indicate few morphologic specializations in the shrew stomach which can be correlated with their high rate of food assimilation and metabolic demands, though future studies of mucosal biochemistry and lower gut morphology may reveal such adaptations. PMID:4020920

Pfeiffer, C J; Keith, J C

1985-07-01

171

Short-Tailed Shrews (Blarina brevicauda) Exhibit Unusual Behavior in an Urban Environment  

Microsoft Academic Search

Ecological studies typically stress the use of habitats by wildlife in natural environments. However, in urban environments, habitat use may be altered, or it may be easier to discern use or behaviors overlooked in more natural settings. This note details unique observations of the northern short-tailed shrew (Blarina brevicauda) congregating around a bird feeder, living in a flower bed isolated

Virgil Brack Jr

172

DEMOGRAPHY OF SHORT-TAILED SHREW POPULATIONS LIVING ON PCB CONTAMINATED SITES  

Microsoft Academic Search

In ecological risk assessment, a key necessity is to understand how contaminants known to have negative impact on laboratory mammals affect the population demography of mammals living in their natural environment. We examined the demography of six local populations of the short-tailed shrew (Blarina brevicauda) living in eastern deciduous forest palustrine habitat along the Housatonic River, Massachusetts on soils contaminated

RUDY BOONSTRA

2002-01-01

173

Colonization of Ireland: revisiting 'the pygmy shrew syndrome' using mitochondrial, Y chromosomal and microsatellite markers  

PubMed Central

There is great uncertainty about how Ireland attained its current fauna and flora. Long-distance human-mediated colonization from southwestern Europe has been seen as a possible way that Ireland obtained many of its species; however, Britain has (surprisingly) been neglected as a source area for Ireland. The pygmy shrew has long been considered an illustrative model species, such that the uncertainty of the Irish colonization process has been dubbed ‘the pygmy shrew syndrome'. Here, we used new genetic data consisting of 218 cytochrome (cyt) b sequences, 153 control region sequences, 17 Y-intron sequences and 335 microsatellite multilocus genotypes to distinguish between four possible hypotheses for the colonization of the British Isles, formulated in the context of previously published data. Cyt b sequences from western Europe were basal to those found in Ireland, but also to those found in the periphery of Britain and several offshore islands. Although the central cyt b haplotype in Ireland was found in northern Spain, we argue that it most likely occurred in Britain also, from where the pygmy shrew colonized Ireland as a human introduction during the Holocene. Y-intron and microsatellite data are consistent with this hypothesis, and the biological traits and distributional data of pygmy shrews argue against long-distance colonization from Spain. The compact starburst of the Irish cyt b expansion and the low genetic diversity across all markers strongly suggests a recent colonization. This detailed molecular study of the pygmy shrew provides a new perspective on an old colonization question. PMID:21673740

McDevitt, A D; Vega, R; Rambau, R V; Yannic, G; Herman, J S; Hayden, T J; Searle, J B

2011-01-01

174

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

PubMed Central

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 virus–host relationship. PMID:21896819

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

2011-01-01

175

Short report: Genetic diversity of Thottapalayam virus, a Hantavirus harbored by the Asian house shrew (Suncus murinus) in Nepal.  

PubMed

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 virus-host relationship. PMID:21896819

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

2011-09-01

176

Varied behavioral responses induced by morphine in the tree shrew: a possible model for human opiate addiction  

PubMed Central

Tree shrews represent a suitable animal model to study the pathogenesis of human diseases as they are phylogenetically close to primates and have a well-developed central nervous system that possesses many homologies with primates. Therefore, in our study, we investigated whether tree shrews can be used to explore the addictive behaviors induced by morphine. Firstly, to investigate the psychoactive effect of morphine on tree shrews’ behavior, the number of jumping and shuttling, which represent the vertical and horizontal locomotor activity respectively, was examined following the injection of different dosage of morphine. Our results showed intramuscular (IM) injection of morphine (5 or 10 mg/kg) significantly increased the locomotor activity of tree shrews 30–60 min post-injection. Then, using the conditioned place preference/aversion (CPP/CPA) paradigm, we found morphine-conditioned tree shrews exhibited place preference in the morphine-paired chamber on the test day. In addition, naloxone-precipitated withdrawal induced place aversion in the chronic morphine-dependent tree shrews. We evaluated the craving for morphine drinking by assessing the break point that reflects the maximum effort animals will expend to get the drug. Our data showed the break point was significantly increased when compared to the baseline on the 1st, 7th and 14th day after the abstinence. Moreover, in the intravenous morphine self-administration experiment, tree shrews conditioned with morphine responded on the active lever significantly more frequently than on the inactive lever after training. These results suggest that tree shrew may be a potential candidate for study the addictive behaviors and the underling neurological mechanisms. PMID:25294994

Shen, Fang; Duan, Ying; Jin, Shubo; Sui, Nan

2014-01-01

177

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

PubMed Central

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 14–16 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

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

2009-01-01

178

Diverse Interleukin-7 mRNA Transcripts in Chinese Tree Shrew (Tupaia belangeri chinensis)  

PubMed Central

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

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

2014-01-01

179

Structure of corneal layers, collagen fibrils, and proteoglycans of tree shrew cornea  

PubMed Central

Purpose The stroma is the major part of the cornea, in which collagen fibrils and proteoglycans are distributed uniformly. We describe the ultrastructure of corneal layers, collagen fibrils (CF), and proteoglycans (PGs) in the tree shrew cornea. Methods Tree shrew corneas (5, 6, and 10 week old animals) and normal human corneas (24, 25, and 54 years old) were fixed in 2.5% glutaraldehyde containing cuprolinic blue in a sodium acetate buffer. The tissue was processed for electron microscopy. The ‘iTEM Olympus Soft Imaging Solutions GmbH’ program was used to measure the corneal layers, collagen fibril diameters and proteoglycan areas. Results The tree shrew cornea consists of 5 layers: the epithelium, Bowman’s layer, stroma, Descemet’s membrane, and endothelium. The epithelium was composed of squamous cells, wing cells and basal cells. The Bowman’s layer was 5.5±1.0 µm thick and very similar to a normal human Bowman’s layer. The stroma was 258±7.00 µm thick and consisted of collagen fibril lamellae. The lamellae were interlaced with one another in the anterior stroma, but ran parallel to one another in the middle and posterior stroma. Collagen fibrils were decorated with proteoglycan filaments with an area size of 390 ±438 nm2. The collagen fibril had a minimum diameter of 39±4.25 nm. The interfibrillar spacing was 52.91±6.07 nm. Within the collagen fibrils, very small electron-dense particles were present. Conclusions The structure of the tree shrew cornea is very similar to that of the normal human cornea. As is the case with the human cornea, the tree shrew cornea had a Bowman's layer, lamellar interlacing in the anterior stroma and electron-dense particles within the collagen fibrils. The similarities of the tree shrew cornea with the human cornea suggest that it could be a good structural model to use when studying changes in collagen fibrils and proteoglycans in non-genetic corneal diseases, such as ectasia caused after LASIK (laser-assisted in situ keratomileusis). PMID:21921979

Almubrad, Turki

2011-01-01

180

Airoldi, J.-P. & Flury, B. (1988). An application of common principal component analysis to cranial morphometry of Microtus californicus and M. ochrogaster (Mammalia, Rodentia). J.  

E-print Network

morphometry of Microtus californicus and M. ochrogaster (Mammalia, Rodentia). J. Zool., Lond. 216 (1) : 21 males and females of Microtus californicus and M. ochrogaster is presented, comparing PCA, CPC

Airoldi, Jean-Pierre

181

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

PubMed Central

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

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

182

Scanning electron microscopic study on pineal vascularization of the common tree shrew (Tupaia glis).  

PubMed

The detailed blood supply including microvascularization of pineal gland in the common tree shrew (Tupaia glis) was investigated using a vascular corrosion cast technique in conjunction with scanning electron microscopy. Adult common tree shrews of both sexes, divided into 3 groups, were injected with red latex, blue vinyl resin, and Batson's No. 17 plastic mixture for the studies of arterial supply, venous drainage, and microvasculature of the pineal gland, respectively. It was found that the pineal gland is a highly vascularized organ. It receives two to four branches from the medial posterior choroidal arteries. Two types of capillary arrangements, fan-like and network, are observed. As in the human, usually one and occasionally two pineal veins, draining directly into the great cerebral vein of Galen, are observed. A pineal portal system is not demonstrated. PMID:2056434

Chunhabundit, P; Somana, R

1991-03-01

183

Risk-sensitive foraging behaviour of the round-eared elephant shrew ( Macroscelides proboscideus )  

Microsoft Academic Search

We examined the risk-sensitive foraging behaviour of the round-eared elephant shrew by open-economy choice experiments, in which animals were deprived of food immediately prior to experiments but given food ad libitum afterwards, to test the energy budget rule. The energy budget rule states that if an animal's (daily) energy budget is negative it should behave in a risk-prone manner. A

M. J. Lawes; M. R. Perrin

1995-01-01

184

Habitat Associations of Vancouver Island Water Shrews in Restored and Natural Stream Habitats  

Microsoft Academic Search

The Vancouver Island water shrew (Sorex palustris brooksi)1 is a rare subspecies found only on Vancouver Island, British Columbia. It is a riparian specialist, specially adapted to a semi-aquatic lifestyle and strongly associated with the land\\/water interface. Human-related activities on Vancouver Island have resulted in the loss or degradation of habitat for S. p. brooksi. Mitigation efforts aimed at stream

VANESSA J. CRAIG; STEVEN F. WILSON

185

Early-life nutritional environment and spatial navigation in the water shrew, Sorex palustris (Insectivora).  

PubMed

Studies were conducted to study the effects of early-life nutritional environment on spatial navigation ability in the water shrew (Sorex palustris), as well as to provide information on life history traits and husbandry. The mean longevity of males and females in captivity was 652.3 +/- 33.8 SD and 616.2 +/- 22.5 days, respectively. Litter sizes ranged from 5 to 8 and neonatal mass ranged from 0.71 to 0.83 g. Spatial navigation was examined by use of the Morris water apparatus, where animals were required to locate the position of an escape platform in a circular tank of water. The platform was visible (proximal cue version of the task) in some tests. In other tests it was hidden beneath the surface (distal cue version) by making the water opaque using a non-toxic white dye. The tank was divided into 4 quadrants and the position of the plafform in any quadrant could be fixed for any subject or varied between subjects. Early-life under-nutrition was achieved by maintaining some shrews on a restricted diet (received half the amount of food as did controls). Under-nutrition was found to have an adverse effect on spatial navigation. Regardless of nutritional status, shrews were able to locate a hidden plafform that was placed at the center of a given quadrant more rapidly (escape latency) when it was visible (44 to 69 sec) than when it was hidden (83 to 164 sec). Results also showed that these shrews utilize both proximal and distal cues in this spatial task. Control subjects spent more time at a location where the platform had been in a previous test (69% of the trial period) than their undernourished counterparts (45 to 51%). This is the first experimental analysis of spatial navigation and the effects of early-life under-nutrition on this task, for S. palustris. PMID:15907068

Punzo, F

2004-10-01

186

Factors affecting the distribution of Sorex samniticus , an endemic Italian shrew, in an heterogeneous landscape  

Microsoft Academic Search

We studied the factors affecting the distribution of an endemic shrewSorex samniticus Altobello, 1926 in the Province of Siena, central Italy. Distribution data were obtained by examining pellets from 31 barn\\u000a owlTyto alba sites (roosts) over a period spanning from 1974 to 2005. We constructed a model using logistic regression analysis on presence\\/absence\\u000a data. Results show that an increase in

Alessio Mortelliti; Giovanni Amori; Giampiero Sammuri; Luigi Boitani

2007-01-01

187

A NEW LATE MIOCENE SPECIES OF PARACOLOBUS AND OTHER CERCOPITHECOIDEA (MAMMALIA: PRIMATES) FOSSILS FROM LEMUDONG'O, KENYA  

Microsoft Academic Search

The Colobinae (Mammalia: Primates) are relatively unknown from the middle to late Miocene of eastern Africa. When they appear in the Pliocene fossil record they are unambiguous and fairly diverse taxonomically, geographically, and ecologically. The primate fauna from the late Miocene of Lemudong'o is dominated by colobines and therefore represents one of the richest fossil assemblages yet published of this

LESLEA J. HLUSKO

188

Nuclear DNA phylogeny of the squirrels (Mammalia: Rodentia) and the evolution of arboreality from c-myc and RAG1  

E-print Network

Nuclear DNA phylogeny of the squirrels (Mammalia: Rodentia) and the evolution of arboreality from c 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

Steppan, Scott

189

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

Microsoft Academic Search

Pterygodermatites (Mesopectines) nycticebi (Mönnig, 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

Yatsukaho Ikeda; Akiko Fujisaki; Koichi Murat; Hideo Hasegawa

190

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

PubMed Central

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

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

2009-01-01

191

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

SciTech Connect

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.

Randolph, J.C.

1980-01-01

192

Distribution of lectin binding in the testes of the musk shrew, Suncus murinus.  

PubMed Central

Distribution of lectin binding in the testis of the musk shrew, Suncus murinus, was investigated by light and transmission electron microscopy. Not only spermatogenic cells but also Sertoli cells bound some lectins. Canavalia ensiformis agglutinin (Con A) and wheat germ agglutinin (WGA, Triticum vulgaris), indicating the presence of D-mannose and N-acetyl-D-glucosamine respectively, showed an intense reaction in the acrosomal region of early to late spermatids. Ricinus communis agglutinin I (RCA-I), peanut agglutinin (PNA, Arachis hypogaea), Bauhinia purpurea agglutinin (BPA), soybean agglutinin (SBA, Glycine max), revealing the presence of D-galactose and/or N-acetyl-D-galactosamine, bound to the acrosomal region from Golgi to acrosome-phase spermatids and abruptly decreased in intensity in maturation-phase spermatids. GS-II, indicating the presence of N-acetyl-D-glucosamine, gave an intense reaction only in the acrosome of acrosome-phase spermatids. These findings demonstrate that the appearance/disappearance of some glycoconjugates in the spermatid acrosome occurs in the musk shrew during acrosomal formation. Additionally, RCA-I, PNA and BPA revealed a strong reaction in the cytoplasm of Sertoli cells. The reaction that was observed in the intramembranous region of Sertoli cell cytoplasm at the electron microscope level appeared from stages VIII to XIII but not from stages I to VII. This finding suggests that glycoconjugates containing D-galactose may change stage-dependently in the musk shrew Sertoli cell. Images Fig. 1 Fig. 2 Fig. 3 PMID:7591995

Kurohmaru, M; Kobayashi, H; Kanai, Y; Hattori, S; Nishida, T; Hayashi, Y

1995-01-01

193

Cardiac musculature of the cranial vena cava in the common tree shrew (Tupaia glis).  

PubMed Central

Cardiac musculature of the cranial vena cava in the common tree shrew (Tupaia glis) was examined by light and transmission electron microscopy. The common tree shrew has well developed cardiac myocyte layers in the tunica media of the cranial vena cava, extending from the right atrium to the root of the subclavian vein. Because the common tree shrew belongs to a primitive group of mammals, the occurrence of cardiac musculature in the cranial vena cava may be a common feature in lower mammals. The development of this musculature indicates that active contraction of the cranial vena cava wall occurs in this species. Electron micrographs showed the typical ultrastructure of myocytes and nerve endings. These observations suggest that this musculature may serve as a regulatory pump for the return of venous blood to the right atrium and as a blood reservoir system under conditions of rapid heart rate. Additionally, the presence of atrial natriuretic polypeptide (ANP) was also demonstrated in the myocytes of the vena cava immunohistochemically. These findings show that the cardiac endocrine organ for ANP develops even in the principal veins including the cranial vena cava. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7591997

Endo, H; Maeda, S; Kimura, J; Yamada, J; Rerkamnuaychoke, W; Chungsamarnyart, N; Tanigawa, M; Kurohmaru, M; Hayashi, Y; Nishida, T

1995-01-01

194

How did pygmy shrews colonize Ireland? Clues from a phylogenetic analysis of mitochondrial cytochrome b sequences.  

PubMed Central

There is a long-standing debate as to how Ireland attained its present fauna; we help to inform this debate with a molecular study of one species. A 1110 base pair fragment of the mitochondrial cytochrome b gene was sequenced in 74 specimens of the pygmy shrew, Sorex minutus, collected from throughout its western Palaearctic range. Phylogenetic analysis of these sequences revealed several well-supported lineages. Most of the 65 haplotypes belonged to a northern lineage, which ranged from Britain in the west to Lake Baikal in the east. The other lineages were largely limited to Iberia, Italy and the Balkans. One exception, however, was a lineage found in both Ireland and Andorra. This affinity, and the large difference between the mitochondrial sequences of Irish and British individuals, suggest that pygmy shrews did not colonize Ireland via a land connection from Britain, as has been previously supposed, but instead were introduced by boat from southwest continental Europe. All the Irish pygmy shrews analysed were identical or very similar in cytochrome b sequence, suggesting an extreme founding event. PMID:12908980

Mascheretti, Silvia; Rogatcheva, Margarita B; Gunduz, Islam; Fredga, Karl; Searle, Jeremy B

2003-01-01

195

Cardiac ultrastructure and electrocardiogram of the short-tailed shrew, Blarina brevicauda.  

PubMed

The smaller species of shrews have been of considerable interest to scientists because of their high rate of metabolism, structure-functional and behavioral adaptations to support their energy demands. The present data are the first detailed cardiac ultrastructural findings and electrocardiographic (ECG) data of adult and immature small short-tailed shrews, Blarina brevicauda. The heart is morphologically elongated and heart rates in excess of 900 b/min were observed, but ECG components and pattern are non-distinctive for this species. Ultrastructurally, the sarcomeres, tubular and sarcotubular systems and Purkinje cells resemble closely those observed in larger, less active mammals. Several distinctive features resembling those seen in some other shrews or hummingbirds exist, including reduced quantities of myocyte glycogen, irregularly shaped and tightly packed mitochondria, increased neural and vascular elements in the myocardium, and small size and unusual dispersion of atrial specific granules. These morphologic findings suggest that the remarkable physiologic performance of the heart of Blarina brevicauda is supported by a combination of macroscopic, histologic and cellular adaptations. PMID:8269404

Pfeiffer, C J; Keith, J C

1993-10-01

196

Pulmonary appendix of the short-tailed shrew (Blarina): a unique immunologic organ.  

PubMed

The right bronchus of the short-tailed shrew, Blarina brevicauda, terminates in a nonrespiratory pulmonary appendix (PA) containing two bronchial extensions. The experimentally demonstrated ability of these structures to collect and peristaltically expel aspirated material was initially assumed to be a sufficient reason for their developmental persistence, but as bronchus associated lymphoid tissue (BALT) became a subject of immunologic interest in other species, a possible immunologic role for the concentrations of BALT observed in the shrew PA were investigated. As the BALT of the PA contained many well-differentiated plasma cells and numerous particle-containing macrophages, 6-mu paraffin sections were treated with an immunoperoxidase avidin-biotin preparation that chromogenically identified alpha chains of IgA in many of the PA plasma cells and their associated luminal secretions. Also, vascular injections revealed that the PA had a complex relationship with anastomotic sinusoids connecting the bronchial and pulmonary circulation systems, and scanning electron microscopy showed that the luminal epithelial surfaces of the PA were virtually identical to the scattered BALT aggregates in the bronchi of other animals. It thus appeared that these unique structures in the shrew are morphologically and topographically suited to receive aspirated antigens that induce secretory IgA production, while possibly providing other humoral and cellular immunologic products to the general circulation. PMID:11870601

Parke, Wesley Wilkin

2002-03-01

197

The taming of the shrew milk teeth Elina Jarvinen,a, Kaisa Valimaki,b Marja Pummila,a Irma Thesleff,a and Jukka Jernvalla  

E-print Network

The taming of the shrew milk teeth Elina Ja¨rvinen,a,� Kaisa Va¨lima¨ki,b Marja Pummila,a Irma dentition is the evolutionary reduction of tooth number and replace- ment. Because mice do not replace teeth. Historically, shrews have been reported to initiate the development of several, milk or deciduous teeth

Merilä, Juha

198

Phylogeography of the mole-shrew ( Anourosorex yamashinai ) in Taiwan: implications of interglacial refugia in a high-elevation small mammal  

Microsoft Academic Search

To test the Pleistocene interglacial refugia hypothesis with a high-elevation mammal, we studied the phylogeography of the mole-shrew ( Anourosorex yamashinai ) using partial mitochondrial cytochrome b gene sequences (737 bases). This shrew is endemic to Taiwan. It is mainly distributed in the highlands from 1000 to 2500 m in elevation. We examined 103 specimens from 24 localities in three

SHOU-LI YUAN; LIANG-KONG LIN; TATSUO OSHIDA

199

Accumulation of chlorine-36 ring-labeled DDT residues in various tissues of two species of shrew  

Microsoft Academic Search

Storage of DDT [trichloro-bis-(p-chlorophenyl) ethane] residues by the shrew species,Blarina brevicauda andSorex cinereus, was studied in a 4.05-hectare old-field ecosystem, treated in June, 1969, with36Cl-ring-labeled DDT at a dosage of 0.92 kilograms per hectare. The mean radioactive DDT-derived residue contents ofBlarina liver (10 ppm), muscle (10 ppm), brain (4 ppm), and fat (135 ppm) of resident shrews were the same

D. J. Forsyth; T. J. Peterle

1973-01-01

200

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

NASA Astrophysics Data System (ADS)

The Mission Paléoanthropologique Franco-Tchadienne (MPFT) found a new species of Orycteropodidae (Mammalia, Tubulidentata) in the Kollé 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 Kollé 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.

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

2004-12-01

201

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

SciTech Connect

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.

Bosveld, A.T.C.; Bie, P. de; Weggemans, J. [Inst. for Forestry and Nature Research, Wageningen (Netherlands); Murk, A. [Agricultural Univ., Wageningen (Netherlands). Dept. of Toxicology

1995-12-31

202

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

SciTech Connect

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.

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

2004-01-01

203

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

PubMed

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

Schneiderová, Irena; Zouhar, Jan

2014-01-01

204

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

PubMed Central

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

Schneiderová, Irena; Zouhar, Jan

2014-01-01

205

Differential protein expression in Tree Shrew sclera during development of lens-induced myopia and recovery  

PubMed Central

Purpose The tree shrew model of refractive development is particularly useful because, like humans, tree shrews have a fibrous sclera. Selective changes in some candidate extracellular matrix proteins and mRNAs have been found in the sclera during the development of, and recovery from, induced myopia. We undertook a more neutral proteomic analysis using two-dimensional gel electrophoresis and mass spectrometry to identify scleral proteins that are differentially expressed during the development of, and recovery from, lens-induced myopia. Methods Five tree shrews (Tupaia glis belangeri) wore a monocular –5 D lens for 4 days, starting 24 days after natural eye opening. At the end of this time, all treated eyes had partially compensated for the lens and were –3.5±0.7 D (mean ± SEM) myopic relative to the untreated fellow control eyes. An additional five animals wore a –5 D lens for 11–13 days, followed by 4 days of recovery without the –5 D lens. The amount of recovery was 1.6±0.4 D. Scleral proteins from both groups were then isolated and resolved by two-dimensional gel electrophoresis and spots that were differentially expressed were identified by mass spectrometry. Results The scleral protein profile typically displayed ~700 distinct protein spots within the pH 5–8 range. Comparison of the treated-eye and control-eye scleras of the lens-compensation animals revealed five spots that were significantly differentially expressed in all five pairs of eyes; all were downregulated 1.2 to 1.7 fold in the treated eye. These proteins were identified as: pigment epithelium-derived factor (PEDF), procollagen I ?1, procollagen I ?2, and thrombospondin I (two spots). In the recovering eyes, the two thrombospondin I spots remained lower in abundance while PEDF and the procollagens were no longer downregulated. In addition, 78 kDa glucose-regulated protein (GRP 78), a member of the heat shock protein 70 family, was slightly upregulated 1.3 fold. Conclusions We found consistent results across animals that were of a magnitude consistent with the physiologically small changes to the focal plane of these eyes. Changes in collagen confirm previous findings, but downregulation of thrombospondin I adds detail to our understanding of the chain of signals that regulates scleral creep rate. The differential changes in PEDF and GRP 78 were not expected, based on previous studies, and demonstrate the utility of the proteomic approach in tree shrew sclera. PMID:17893659

Norton, Thomas T.

2007-01-01

206

Molecular Ecology (2001) 10, 12271240 2001 Blackwell Science Ltd  

E-print Network

Phylogeography of the dusky shrew, Sorex monticolus (Insectivora, Soricidae): insight into deep and shallow 99775­6960, USA Abstract Phylogenetic relationships among the dusky shrew (Sorex monticolus) and eight. bairdi, S. neomexicanus and S. pacificus) were poorly differentiated. Sorex ornatus and S. vagrans

207

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

ERIC Educational Resources Information Center

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…

Takahashi, Makoto; Ushitani, Tomokazu; Fujita, Kazuo

2008-01-01

208

Eimeria Korros and E. Modesta Spp. N. (Protozoa: Eimeriidae) from a Snake and a Tree Shrew in South Vietnam.  

National Technical Information Service (NTIS)

Two new coccidia are described from vertebrates of Vietnam: Eimeria korros sp.n. from a snake, Ptayas korros, and Eimeria modesta sp. n. from the tree shrew, Tupaia glis modesta. Endogenous reproduction of the snake Eimeria occurred in the gall bladder ep...

P. F. D. Van Peenen, P. F. Ryan, T. J. McIntyre

1967-01-01

209

Short-term response of shrews to prescribed fire and mechanical fuel reduction in a Southern Appalachian upland hardwood forest  

Microsoft Academic Search

As part of the multidisciplinary National Fire and Fire Surrogate study, we used drift fences with pitfall traps from May to September 2003 and 2004 to determine how three fuel reduction techniques affected shrews in the Southern Appalachian Mountains of North Carolina. Ground-dwelling macroarthropods also were collected from a subset of pitfall traps to assess relative prey availability among the

Cathryn H. Greenberg; Stanlee Miller; Thomas A. Waldrop

2007-01-01

210

Neurogenesis in the Dentate Gyrus of the Adult Tree Shrew Is Regulated by Psychosocial Stress and NMDA Receptor Activation  

Microsoft Academic Search

These studies were designed to determine whether adult neu- rogenesis occurs in the dentate gyrus of the tree shrew, an animal phylogenetically between insectivores and primates, and to explore the possibility that this process is regulated by stressful experiences and NMDA receptor activation. We per- formed immunohistochemistry for cell-specific markers and the thymidine analog bromodeoxyuridine (BrdU), a marker of DNA

Elizabeth Gould; Bruce S. McEwen; Patima Tanapat; Liisa A. M. Galea; Eberhard Fuchs

1997-01-01

211

Managing for Habitat Heterogeneity in Grassland Agro-Ecosystems Influences the Abundance of Masked Shrews (Sorex cinereus)  

Microsoft Academic Search

Many agri-environment programs prescribe modified farming practices and provision of heterogeneous habitat types, such as fallow field edges and shelterbelts. The conservation benefit of these actions to biodiversity has been well described. However, the response of insectivorous small mammals to habitat heterogeneity in agro-ecosystems has received little empirical attention. We compared the abundance of the masked shrew (Sorex cinereus) between

Joseph J. Nocera; Kimberly L. Dawe

2008-01-01

212

Tree shrews (Tupaia belangeri) exhibit novelty preference in the novel location memory task with 24-h retention periods.  

PubMed

Novelty preference is pervasive in mammalian species, and describes an inherent tendency to preferentially explore novelty. The novel location memory task studied here assesses the ability of animals to form accurate memories of a spatial configuration, consisting of several identical objects placed within an arena. Tree shrews were first familiarized with a particular object configuration during several sessions, and then an object was displaced during a test session. Tree shrews exhibited enhanced exploration when confronted with this novel configuration. The most reliable indicator associated with novelty preference was an enhancement in directed exploration towards the novel object, although we also observed a non-specific overall increase in exploration in one experiment. During the test session, we also observed an exploration of the location, which had previously been occupied by the displaced object, an effect termed empty quadrant. Our behavioral findings suggest multiple stages of spatial memory formation in tree shrews that are associated with various forms of behavioral responses to novelty. Reduced novelty preference has been linked to major depressive disorder in human patients. Given the established social conflict depression model in tree shrews, we anticipate that the study of the neural circuits of novelty preference and their malfunction during depression may have implications for understanding or treating depression in humans. PMID:24782805

Nair, Jayakrishnan; Topka, Marlene; Khani, Abbas; Isenschmid, Manuela; Rainer, Gregor

2014-01-01

213

Journal of East African Natural History 95(2): 111115 (2006) A POTENTIALLY NEW GIANT SENGI (ELEPHANT-SHREW) FROM  

E-print Network

. They are part of an early placental radiation of African mammals, the Afrotheria, which includes elephants, seaJournal of East African Natural History 95(2): 111­115 (2006) A POTENTIALLY NEW GIANT SENGI (ELEPHANT-SHREW) FROM THE UDZUNGWA MOUNTAINS, TANZANIA Francesco Rovero Sezione di Zoologia dei Vertebrati

214

Distinct Innate Immune Responses in Human Macrophages and Endothelial Cells Infected with Shrew-borne Hantaviruses  

PubMed Central

Although hantaviruses have been previously considered as rodent-borne pathogens, recent studies demonstrate genetically distinct hantaviruses in evolutionarily distant non-rodent reservoirs, including shrews, moles and bats. The immunological responses to these newfound hantaviruses in humans are unknown. We compared the innate immune responses to Imjin virus (MJNV) and Thottapalayam virus (TPMV), two shrew-borne hantaviruses, with that toward two rodent-borne hantaviruses, pathogenic Hantann virus (HTNV) and nonpathogenic Prospect Hill virus (PHV). Infection of human macrophages and endothelial cells with either HTNV or MJNV triggered productive viral replication and up-regulation of anti-viral responsive gene expression from day 1 to day 3 postinfection, compared with PHV and TPMV. Furthermore, HTNV, MJNV and TPMV infection led to prolonged increased production of pro-inflammatory cytokines from days 3 to 7 postinfection. By contrast, PHV infection failed to induce pro-inflammatory responses. Distinct patterns of innate immune activation caused by MJNV suggest that it might be pathogenic to humans. PMID:22944108

Shin, Ok Sarah; Yanagihara, Richard; Song, Jin-Won

2013-01-01

215

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

PubMed

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

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

216

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

USGS Publications Warehouse

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).

Woodman, N.

2005-01-01

217

Anaplasma phagocytophilum strains from voles and shrews exhibit specific ankA gene sequences  

PubMed Central

Background Anaplasma phagocytophilum is a Gram-negative bacterium that replicates obligate intracellularly in neutrophils. It is transmitted by Ixodes spp. ticks and causes acute febrile disease in humans, dogs, horses, cats, and livestock. Because A. phagocytophilum is not transmitted transovarially in Ixodes spp., it is thought to depend on reservoir hosts to complete its life cycle. In Europe, A. phagocytophilum was detected in roe deer, red deer, wild boars, and small mammals. In contrast to roe deer, red deer and wild boars have been considered as reservoir hosts for granulocytic anaplasmosis in humans, dogs, and horses according to groESL- and ankA-based genotyping. A. phagocytophilum variants infecting small mammals in Europe have not been characterized extensively to date. Results We amplified the total ankA open reading frames of 27 strains from voles and shrews. The analysis revealed that they harboured A. phagocytophilum strains that belonged to a distinct newly described ankA gene cluster. Further, we provide evidence that the heterogeneity of ankA gene sequences might have arisen via recombination. Conclusions Based on ankA-based genotyping voles and shrews are unlikely reservoir hosts for granulocytic anaplasmosis in humans, dogs, horses, and livestock in Europe. PMID:24283328

2013-01-01

218

Demography of short-tailed shrew populations living on polychlorinated biphenyl-contaminated sites.  

PubMed

In ecological risk assessment, a key necessity is to understand how contaminants known to have negative impact on laboratory mammals affect the population demography of mammals living in their natural environment. We examined the demography of six local populations of the short-tailed shrew (Blarina brevicauda) living in eastern deciduous forest palustrine habitat along the Housatonic River (MA, USA) on soils contaminated with a range of polychlorinated biphenyl (PCB) concentrations (1.5-38.3 ppm). The objective of the study was to assess whether PCBs adversely affect the population demography of these small mammals living in their natural environment. Blarina were selected for study because they would be expected to readily bioaccumulate PCBs from the soil. Populations were intensively live trapped on 1-ha grids from spring to autumn 2001. There was no relationship between any demographic parameter and PCB soil concentrations. Densities were high (usually exceeding 20/ha, and on two grids exceeded 60/ha in summer); survival was good (typically 60-75% per 30 d); and sex ratio, reproduction rates, growth rates, and body mass were within the ranges reported in the literature. Thus, these shrew populations showed no detectable impact on their population demography from living on PCB-contaminated sites. PMID:12785599

Boonstra, Rudy; Bowman, Lanna

2003-06-01

219

Genetic diversity of Imjin virus in the Ussuri white-toothed shrew (Crocidura lasiura) in the Republic of Korea, 2004-2010  

Microsoft Academic Search

Recently, Imjin virus (MJNV), a genetically distinct hantavirus, was isolated from lung tissues of the Ussuri white-toothed shrew (Crocidura lasiura) captured near the demilitarized zone in the Republic of Korea. To clarify the genetic diversity of MJNV, partial M- and L-segment sequences were amplified from lung tissues of 12 of 37 (32.4%) anti-MJNV IgG antibody-positive Ussuri white-toothed shrews captured between

Se Hun Gu; Hae Ji Kang; Luck Ju Baek; Ji Yun Noh; Heung-Chul Kim; Terry A Klein; Richard Yanagihara; Jin-Won Song

2011-01-01

220

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

USGS Publications Warehouse

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.

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

2001-01-01

221

Gene expression signatures in tree shrew choroid in response to three myopiagenic conditions.  

PubMed

We examined gene expression in tree shrew choroid in response to three different myopiagenic conditions: minus lens (ML) wear, form deprivation (FD), and continuous darkness (DK). Four groups of tree shrews (n=7 per group) were used. Starting 24 days after normal eye opening (days of visual experience [DVE]), the ML group wore a monocular -5D lens for 2 days. The FD group wore a monocular translucent diffuser for 2 days. The DK group experienced continuous darkness binocularly for 11 days, starting at 17 DVE. An age-matched normal group was examined at 26 DVE. Quantitative PCR was used to measure the relative (treated eye vs. control eye) differences in mRNA levels in the choroid for 77 candidate genes. Small myopic changes were observed in the treated eyes (relative to the control eyes) of the ML group (-1.0±0.2D; mean±SEM) and FD group (-1.9±0.2D). A larger myopia developed in the DK group (-4.4±1.0D) relative to Normal eyes (both groups, mean of right and left eyes). In the ML group, 28 genes showed significant differential mRNA expression; eighteen were down-regulated. A very similar pattern occurred in the FD group; twenty-seven of the same genes were similarly regulated, along with five additional genes. Fewer expression differences in the DK group were significant compared to normal or the control eyes of the ML and FD groups, but the pattern was similar to that of the ML and FD differential expression patterns. These data suggest that, at the level of the choroid, the gene expression signatures produced by "GO" emmetropization signals are highly similar despite the different visual conditions. PMID:25072854

He, Li; Frost, Michael R; Siegwart, John T; Norton, Thomas T

2014-09-01

222

Vol. 32, no. 1, pp. 1-14 December 15, 2008 NEW PRIMATES (MAMMALIA) FROM THE EARLY AND MIDDLE EOCENE OF  

E-print Network

with the description of five new fossil primates from the early and middle Eocene of Pakistan. In- cluded among this sample are three adapiforms (including a new genus and three new species), and two omomyiforms (one newVol. 32, no. 1, pp. 1-14 December 15, 2008 NEW PRIMATES (MAMMALIA) FROM THE EARLY AND MIDDLE EOCENE

Licciardi, Joseph M.

223

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

E-print Network

distribution of terrestrial habitats has been altered extensively through time (Heaney 1985; Hall 1998; Voris 2000; Bird et al. 2005). The processes of volcanic uplift and repeated sea level fluctuations represent potential mechanisms promoting evolutionary... et al. 1998; Hutterer 2005; Dubey et al. 2007, 2008). Dubey et al. (2007) estimated the divergence of African from Eurasian Cro- cidura at 5.4–10.7 million years ago (mya), thus the entire history of shrew evolution in Southeast Asia likely took place...

Esselstyn, Jacob Aaron; Timm, Robert M.; Brown, Rafe M.

2009-10-01

224

Blarina toxin, a mammalian lethal venom from the short-tailed shrew Blarina brevicauda: Isolation and characterization  

Microsoft Academic Search

Venomous mammals are rare, and their venoms have not been characterized. We have purified and characterized the blarina toxin (BLTX), a lethal mammalian venom with a tissue kallikrein-like activity from the submaxillary and sublingual glands of the short-tailed shrew Blarina brevicauda. Mice administered BLTX i.p. developed irregular respiration, paralysis, and convulsions before dying. Based on the amino acid sequence of

Masaki Kita; Yasuo Nakamura; Yuushi Okumura; Satoshi D. Ohdachi; Yuichi Oba; Michiyasu Yoshikuni; Hiroshi Kido; Daisuke Uemura

2004-01-01

225

Population dynamics of the northern short-tailed shrew, Blarina brevicauda : insights from a 25-year study  

Microsoft Academic Search

Abstract: The population demography of the northern short-tailed shrew, Blarina brevicauda (Say, 1823), was studied for 25 years in bluegrass, alfalfa, and tallgrass habitats in east-central Illinois. The population in bluegrass had higher over-winter population density, began increasing earlier in the year, peaked earlier in the year, had higher mean monthly densities and amplitudes of fluctuation, and remained higher for

Lowell L. Getz; Joyce E. Hofmann; Betty McGuire; Madan K. Oli

2004-01-01

226

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

PubMed

Pterygodermaties (Mesopectines) nycticebi (Mönnig, 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

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

2003-06-01

227

Phylogeny of the Procyonidae (Mammalia: Carnivora): molecules, morphology and the Great American Interchange.  

PubMed

The Procyonidae (Mammalia: Carnivora) have played a central role in resolving the controversial systematics of the giant and red pandas, but phylogenetic relationships of species within the family itself have received much less attention. Cladistic analyses of morphological characters conducted during the last two decades have resulted in topologies that group ecologically and morphologically similar taxa together. Specifically, the highly arboreal and frugivorous kinkajou (Potos flavus) and olingos (Bassaricyon) define one clade, whereas the more terrestrial and omnivorous coatis (Nasua), raccoons (Procyon), and ringtails (Bassariscus) define another clade, with the similar-sized Nasua and Procyon joined as sister taxa in this latter group. These relationships, however, have not been tested with molecular sequence data. We examined procyonid phylogenetics based on combined data from nine nuclear and two mitochondrial gene segments totaling 6534bp. We were able to fully resolve relationships within the family with strongly supported and congruent results from maximum parsimony, maximum likelihood, minimum evolution, and Bayesian analyses. We identified three distinct lineages within the family: a (Nasua, Bassaricyon) clade, a (Bassariscus, Procyon) clade, and a Potos lineage, the last of which is sister to the other two clades. These findings, which are in strong disagreement with prior fossil and morphology-based assessments of procyonid relationships, reemphasize the morphological and ecological flexibility of these taxa. In particular, morphological similarities between unrelated genera possibly reflect convergence associated with similar lifestyles and diets rather than ancestry. Furthermore, incongruence between the molecular supermatrix and a morphological character matrix comprised mostly of dental characters [Baskin, J.A., 2004. Bassariscus and Probassariscus (Mammalia, Carnivora, Procyonidae) from the early Barstovian (Middle Miocene). J. Vert. Paleo. 24, 709-720] may be due to non-independence among atomized dental characters that does not take into account the high developmental genetic correlation of these characters. Finally, molecular divergence dating analyses using a relaxed molecular clock approach suggest that intergeneric and intrageneric splits in the Procyonidae mostly occurred in the Miocene. The inferred divergence times for intrageneric splits for several genera whose ranges are bisected by the Panamanian Isthmus is significant because they suggest diversification well precedes the Great American Interchange, which has long been considered a primary underlying mechanism for procyonid evolution. PMID:17174109

Koepfli, Klaus-Peter; Gompper, Matthew E; Eizirik, Eduardo; Ho, Cheuk-Chung; Linden, Leif; Maldonado, Jesus E; Wayne, Robert K

2007-06-01

228

Modulation of Glycosaminoglycan Levels in Tree Shrew Sclera during Lens-Induced Myopia Development and Recovery  

PubMed Central

Purpose In juvenile tree shrews, positioning a negative-power lens in front of an eye produces a hyperopic shift in refractive state and causes a compensatory increase in axial length over several days so that the eye is myopic when the lens is removed. During negative lens compensation, the scleral extracellular matrix is remodeled. A biomechanical property of the sclera, creep rate, increases; during recovery from induced myopia, the creep rate decreases below normal levels. Changes in glycosaminoglycan (GAG) levels, including those of hyaluronan, may participate in these changes in creep rate and, in turn, participate in controlling the axial length and refractive state. This study investigated the unsulfated and sulfated GAG composition of the sclera during compensation for a -5 diopter (D) lens and during recovery. Methods Capillary electrophoresis was used to assess the relative levels (ng/mg dry scleral weight) of unsulfated GAGs (hyaluronan [HA] and chondroitin [C0S]), sulfated GAGs (chondroitin-4-sulfate [C4S], chondroitin-6-sulfate [C6S], and dermatan sulfate [DS]) in the sclera of groups of tree shrews (n = 5 per group) that wore a monocular -5 D lens for 1, 2, 4, or 11 days or had 11 days of -5 D lens wear followed by 1, 2, or 4 days of recovery from lens wear. The fellow eye served as an untreated control. Groups of normal and plano lens-treated animals provided age-matched values. Results Expressed as a fraction of dry weight, levels of HA were lower after 1, 4, and 11 days of -5 D lens wear. Levels of C0S, C6S, and C4S were significantly lower after 4 and 11 days of lens wear. After 1 and 2 days of recovery, GAG levels in the treated eyes were not significantly different from those in control eyes. After 4 recovery days, HA levels were lower, but the levels of all other GAGs were not different in the recovering and control eyes. Some binocular changes also occurred. Conclusions The rapid differential decrease in HA levels during negative lens compensation and the absence of any difference after just 1 day of recovery suggest that HA levels may play a previously unrecognized early role in regulating the biomechanical property (creep rate) of the sclera. The reduced levels of the other GAGs, which occur when creep rate is at its peak elevation, and their rapid return to normal after 1 day of recovery suggest that they may also participate in regulating this biomechanical property of the sclera. PMID:17591859

Moring, Anisha G.; Baker, John R.; Norton, Thomas T.

2007-01-01

229

Species of coccidia (Apicomplexa: Eimeriidae) in shrews from Alaska, U.S.A., and northeastern Siberia, Russia, with description of two new species.  

PubMed

Fecal samples (n = 636) from 10 species of shrews collected in Alaska (n = 540) and northeastern Siberia (n = 96) were examined for the presence of coccidia (Apicomplexa: Eimeriidae). Five distinct oocyst morphotypes were observed. Three types were consistent with oocysts of previously recognized coccidia species from other shrew hosts. These were Eimeria inyoni, E. vagrantis, and Isospora brevicauda, originally described from the inyo shrew (Sorex tenellus), dusky shrew (S. monticolus), and northern short-tailed shrew (Blarina brevicauda), respectively. We found 5 new host records for E. inyoni, 3 for E. vagrantis, and 3 for I. brevicauda. The 2 additional oocyst morphotypes, both from the tundra shrew (Sorex tundrensis), are putative new species. Sporulated oocysts of Eimeria beringiacea n. sp. are subspheroidal, 17.7 x 15.6 microm (14-24 x 13-20 microm) with a length (L)/width (W) ratio of 1.1 (1.0-1.4); these lack a micropyle (M), an oocyst residuum (OR), and a polar granule (PG). Sporocysts are ellipsoidal, 10.3 x 6.1 microm (7-14 x 4-8 microm), with a L/W ratio of 1.7 (1.3-2.3) and have a Stieda body (SB), Substieda body (SSB), and sporocyst residuum (SR). Oocysts of Eimeria tundraensis n. sp. are spheroidal to subspheroidal, 24.8 x 23.5 microm (23-26 x 22-25 microm), with a L/W ratio of 1.1 (1.0-1.2); these lack a M and OR, but a single PG is present. Sporocysts are elongate ellipsoidal, 15.4 x 8.3 microm (13-17 x 7-9 microm), with a L/W ratio of 1.9 (1.4-2.1) and have a SB, SSB, and SR. PMID:18576829

Lynch, A J; Duszynski, D W

2008-08-01

230

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

USGS Publications Warehouse

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.

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

2012-01-01

231

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

PubMed

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

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

2012-09-01

232

Aspects of masticatory form and function in common tree shrews, Tupaia glis.  

PubMed

Tree shrews have relatively primitive tribosphenic molars that are apparently similar to those of basal eutherians; thus, these animals have been used as a model to describe mastication in early mammals. In this study the gross morphology of the bony skull, joints, dentition, and muscles of mastication are related to potential jaw movements and cuspal relationships. Potential for complex mandibular movements is indicated by a mobile mandibular symphysis, shallow mandibular fossa that is large compared to its resident condyle, and relatively loose temporomandibular joint ligaments. Abrasive tooth wear is noticeable, and is most marked at the first molars and buccal aspects of the upper cheek teeth distal to P2. Muscle morphology is basically similar to that previously described for Tupaia minor and Ptilocercus lowii. However, in T. glis, an intraorbital part of deep temporalis has the potential for inducing lingual translation of its dentary, and the large medial pterygoid has extended its origin anteriorly to the floor of the orbit, which would enhance protrusion. The importance of the tongue and hyoid muscles during mastication is suggested by broadly expanded anterior bellies of digastrics, which may assist mylohyoids in tensing the floor of the mouth during forceful tongue actions, and by preliminary electromyography, which suggests that masticatory muscles alone cannot fully account for jaw movements in this species. PMID:6854653

Fish, D R

1983-04-01

233

Radiation ecology issues associated with murine rodents and shrews in the Chernobyl exclusion zone.  

PubMed

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 h(-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 h(-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 h(-1), respectively. Contributions of individual radiation sources into the total absorbed dose are described. PMID:21878767

Gaschak, Sergey P; Maklyuk, Yulia A; Maksimenko, Andrey M; Bondarkov, Mikhail D; Jannik, G Timothy; Farfán, Eduardo B

2011-10-01

234

[Soricinia sawadai sp. n. (Cyclophyllidea: Hymenolepididae), a new cestode species from the shrews of Sakhalin Island].  

PubMed

A new species Soricinia sawadai sp. n. parasitizing shrews of Sakhalin Island (Sores unguiculatus and S. caecutiens) is described. The new species differs from other species of the genus Soricinia Spassky et Spasskaja, 1954 in having specific armament and size of the cirrus. Soricinia sawadai sp. n. differs from S. aurita (Irzhavsky et al., 2005) in having half size of the ovary (0.076-0.08 x 0.03-0.038 versus 0.135-0.14 x 0.037-0.04) and the cirrus bursa extending into the aporal fraction of the middle part of segment. The new species differs from S. quarta (Karpenko, 1983) in having half size of the cirrus (0.025-0.026 versus 0.05-0.055) and half number of hexacants in uterine segments (20-22 versus 40-45). The new species differs from S. infirma (Zarnowski, 1955) in having other cirrus armament, larger number of segments and lesser number of hexacants. The species Insectivorolepis macracetobulosa Sawada et Koyasu, 1991 parasitizing Sorex unguiculatus on Hokkaido Island is synonymized with Soricinia quarta. The species Insectivorolepis macracetobulosa sensu Sawada et Harada, 1993 parasitizing Sorex shinto shinto on Honshu Island is described as a separate species Soricinia haradai sp. n. PMID:20795487

Zubova, O A; Guliaev, V D; Kornienko, S A

2010-01-01

235

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

SciTech Connect

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.

Farfan, E.; Jannik, T.

2011-10-01

236

Convergent evolution of novel protein function in shrew and lizard venom.  

PubMed

How do proteins evolve novel functions? To address this question, we are studying the evolution of a mammalian toxin, the serine protease BLTX [1], from the salivary glands of the North American shrew Blarina brevicauda. Here, we examine the molecular changes responsible for promoting BLTX toxicity. First, we show that regulatory loops surrounding the BLTX active site have evolved adaptively via acquisition of small insertions and subsequent accelerated sequence evolution. Second, these mutations introduce a novel chemical environment into the catalytic cleft of BLTX. Third, molecular-dynamic simulations show that the observed changes create a novel chemical and physical topology consistent with increased enzyme catalysis. Finally, we show that a toxic serine protease from the Mexican beaded lizard (GTX) [2] has evolved convergently through almost identical functional changes. Together, these results suggest that the evolution of toxicity might be predictable-arising via adaptive structural modification of analogous labile regulatory loops of an ancestral serine protease-and thus might aid in the identification of other toxic proteins. PMID:19879144

Aminetzach, Yael T; Srouji, John R; Kong, Chung Yin; Hoekstra, Hopi E

2009-12-01

237

Autoradiographic Quantification of Muscarinic Cholinergic Synaptic Markers in Bat, Shrew, and Rat Brain*  

E-print Network

We employed radioligand binding autoradiography to determine the distributions of pre- and postsynaptic cholinergic radioligand binding sites in the brains of two species of bat, one species of shrew, and the rat. High affinity choline uptake sites were measured with [3H]hemicholinium, and presynaptic cholinergic vesicles were identified with [3H]vesamicol. Muscarinic cholinergic receptors were determined with [3H]scopolamine. The distribution patterns of the three cholinergic markers were simitar in all species examined, and identified known major cholinergic pathways on the basis of enrichments in both pre- and postsynaptic markers. In addition, there was excellent agreement, both within and across species, in the regional distributions of the two presynaptic cholinergic markers. Our results indicate that pharmacological identifiers of cholinergic pathways and synapses, including the cholinergic vesicle transport site, and the organizations of central nervous system cholinergic pathways are phylogenetically conserved among eutherian mammals. KEY WORDS: Vesamicol; hemicholinium-3; scopolamine; muscarinic receptor; high-affinity choline uptake; cholinergic vesicle.

Roger L. Albin; Morgan M. Howl; Donald S. Higgins; Kirk A. Frey

1993-01-01

238

Spatio-temporal patterns of habitat use in voles and shrews modified by density, season and predators.  

PubMed

1.?Although the intrinsic habitat preferences of a species can be considered to be fixed, the realized habitat use depends on the prevailing abiotic and biotic conditions. Often the core habitats are occupied by dense and stable populations, while marginal habitats become occupied only at times of high density. In a community of interacting species, habitat uses of different species become inter-related, for example an increased density of a strong competitor forcing a weaker competitor to use more marginal habitats. 2.?We studied the spatio-temporal distribution patterns of three common small mammal species, the bank vole Myodes glareolus; the field vole Microtus agrestis; and the common shrew Sorex araneus, in a 4-year trapping study carried out on six large islands, each containing a mixture of three main habitat types (forest, field and clear-cut). We experimentally released least weasels (Mustela n. nivalis) to some of the islands to see how the focal species respond to increased predation pressure. 3.?Both vole species were largely restricted to their core habitats (bank voles to forests and field voles to fields) at times of low population density. With increasing density, the relative habitat use of both species increased in the clear-cut areas. The common shrew was a generalist in its habitat use at all population densities. 4.?The release of the weasels changed the habitat use of all study species. 5.?The vole species showed a stronger aggregated pattern than the common shrew, especially at low population density. The vole aggregations remained in the same localities between seasons, except in the case of bank voles after the weasels were released. 6.?Bank voles and field voles avoided each other at high density. 7.?We conclude that intrinsically differential habitat requirements and flexibility to modify habitat use facilitate the coexistence of the two competing vole species in mosaic landscapes consisting of boreal forests and open habitats. PMID:22325037

Sundell, Janne; Church, Christina; Ovaskainen, Otso

2012-07-01

239

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

PubMed Central

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

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

240

Gene expression signatures in tree shrew choroid during lens-induced myopia and recovery.  

PubMed

Gene expression in tree shrew choroid was examined during the development of minus-lens induced myopia (LIM, a GO condition), after completion of minus-lens compensation (a STAY condition), and early in recovery (REC) from induced myopia (a STOP condition). Five groups of tree shrews (n = 7 per group) were used. Starting 24 days after normal eye-opening (days of visual experience [DVE]), one minus-lens group wore a monocular -5 D lens for 2 days (LIM-2), another minus-lens group achieved stable lens compensation while wearing a monocular -5 D lens for 11 days (LIM-11); a recovery group also wore a -5 D lens for 11 days and then received 2 days of recovery starting at 35 DVE (REC-2). Two age-matched normal groups were examined at 26 DVE and 37 DVE. Quantitative PCR was used to measure the relative differences in mRNA levels in the choroid for 77 candidate genes that were selected based on previous studies or because a whole-transcriptome analysis suggested their expression would change during myopia development or recovery. Small myopic changes were observed in the treated eyes of the LIM-2 group (-1.0 ± 0.2 D; mean ± SEM) indicating eyes were early in the process of developing LIM. The LIM-11 group exhibited complete refractive compensation (-5.1 ± 0.2 D) that was stable for five days. The REC-2 group recovered by 1.3 ± 0.3 D from full refractive compensation. Sixty genes showed significant mRNA expression differences during normal development, LIM, or REC conditions. In LIM-2 choroid (GO), 18 genes were significantly down-regulated in the treated eyes relative to the fellow control eyes and 10 genes were significantly up-regulated. In LIM-11 choroid (STAY), 10 genes were significantly down-regulated and 12 genes were significantly up-regulated. Expression patterns in GO and STAY were similar, but not identical. All genes that showed differential expression in GO and STAY were regulated in the same direction in both conditions. In REC-2 choroid (STOP), 4 genes were significantly down-regulated and 18 genes were significantly up-regulated. Thirteen genes showed bi-directional regulation in GO vs. STOP. The pattern of differential gene expression in STOP was very different from that in GO or in STAY. Significant regulation was observed in genes involved in signaling as well as extracellular matrix turnover. These data support an active role for the choroid in the signaling cascade from retina to sclera. Distinctly different treated eye vs. control eye mRNA signatures are present in the choroid in the GO, STAY, and STOP conditions. The STAY signature, present after full compensation has occurred and the GO visual stimulus is no longer present, may participate in maintaining an elongated globe. The 13 genes with bi-directional expression differences in GO and STOP responded in a sign of defocus-dependent manner. Taken together, these data further suggest that a network of choroidal gene expression changes generate the signal that alters scleral fibroblast gene expression and axial elongation rate. PMID:24742494

He, Li; Frost, Michael R; Siegwart, John T; Norton, Thomas T

2014-06-01

241

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

PubMed Central

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

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

242

Comparative morphology and morphometry of the nasal fossae of four species of North American shrews (Soricinae).  

PubMed

The present study compares the morphology of the nasal conchae and the relative development (i.e., surface area and neurosensory cell number) of the olfactory epithelium between four species of shrews occupying different ecotopes (Blarina brevicauda, Sorex cinereus, S. fumeus, S. palustris). The number of olfactory cells was corrected for split cell error. Data were analyzed by using size indices based on the allometric method. The convoluted shape of the maxilloturbinal in Blarina, with large respiratory epithelial surface area, could not be related with certainty to the subterranean ecotope. From the comparison between Soricinae and Crocidurinae, one major difference concerned the shape and attachment of ectoturbinal 3. Differences in the relative development of the olfactory organ are discussed with regard to differences in the use of chemical signals. The semi-fossorial B. brevicauda, with the more developed olfactory organ, is reported to possess more scent-glands and to manifest active scent-marking behaviors and fecal deposits associated with territoriality. The two terrestrial species, S. cinereus and S. fumeus, have olfactory epithelia showing an intermediate development. Published accounts of fewer scent-glands and a lack of active scent-marking behavior indicate a lesser use of olfactory communication in these two species where mutual avoidance seems the rule. Indication of an even more reduced use of olfactory signals in social interactions by the semiaquatic S. palustris is suggested by its least-developed olfactory epithelium. The comparison between Soricinae and Crocidurinae supports a relationship between the development of the olfactory organ and the relative use of olfactory communication known to occur in social interactions. PMID:2618929

Larochelle, R; Baron, G

1989-11-01

243

Diffuse and Specific Tectopulvinar Terminals in the Tree Shrew: Synapses, Synapsins, and Synaptic Potentials  

PubMed Central

The pulvinar nucleus of the tree shrew receives both topographic (specific) and nontopographic (diffuse) projections from superior colliculus (SC), which form distinct synaptic arrangements. We characterized the physiological properties of these synapses and describe two distinct types of excitatory postsynaptic potentials (EPSPs) that correlate with structural properties of the specific and diffuse terminals. Synapses formed by specific terminals were found to be significantly longer than those formed by diffuse terminals. Stimulation of these two terminal types elicited two types of EPSPs that differed in their latency and threshold amplitudes. In addition, in response to repetitive stimulation (0.5–20 Hz) one type of EPSP displayed frequency-dependent depression whereas the amplitudes of the second type of EPSP were not changed by repetitive stimulation of up to 20Hz. To relate these features to vesicle release, we compared the synapsin content of terminals in the pulvinar nucleus and the dorsal lateral geniculate (dLGN) by combining immunohistochemical staining for synapsin I or II with staining for the type 1 or type 2 vesicular glutamate transporters (markers for corticothalamic and tectothalamic/retinogeniculate terminals, respectively). We found that retinogeniculate terminals do not contain either synapsin I or synapsin II, corticothalamic terminals in the dLGN and pulvinar contain synapsin I, but not synapsin II, whereas tectopulvinar terminals contain both synapsin I and synapsin II. Finally, both types of EPSPs showed a graded increase in amplitude with increasing stimulation intensity, suggesting convergence; this was confirmed using a combination of anterograde tract tracing and immunocytochemisty. We suggest that the convergent synaptic arrangements, as well as the unique synapsin content of tectopulvinar terminals, allow them to relay a dynamic range of visual signals from the SC. PMID:21858222

Wei, Haiyang; Masterson, Sean P.; Petry, Heywood M.; Bickford, Martha E.

2011-01-01

244

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

Microsoft Academic Search

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

S. DUBEY; J. F. COSSON; E. MAGNANOU; V. VOHRALÍK; P. BENDA; D. FRYNTA; R. HUTTERER; V. VOGEL; P. VOGEL

2007-01-01

245

Splenic Mass of Masked Shrews, Sorex cinereus, in Relation to Body Mass, Sex, Age, Day of the Year, and Bladder Nematode, Liniscus (=Capillaria) maseri, Infection  

Microsoft Academic Search

The spleen is an important organ of vertebrates. Splenic mass can change in response to a variety of factors. We tested whether splenic mass of masked shrews, Sorex cinereus, was related to sex, age, time of the year, or intensity of bladder nematode (Liniscus (Capil- laria) maseri) infection, after controlling for host body mass. For fe- males, body mass was

Krystyna M. Cowan; Dave Shutler; Thomas B. Herman; Donald T. Stewart

2009-01-01

246

Description and molecular differentiation of a new Staphylocystoides (Cyclophyllidea: Hymenolepididae) from the dusky shrew Sorex monticolus in Southeast Alaska.  

PubMed

Staphylocystoides gulyaevi n. sp. is described based on specimens obtained from the dusky shrew Sorex monticolus collected on Sukkwan Island, southeast Alaska. Staphylocystoides gulyaevi n. sp. is compared with other North American members of the genus having 10 rostellar hooks. The new species is morphologically similar to Staphylocystoides parvissima and Staphylocystoides asketus. The uterus in S. gulyaevi n. sp. develops much more rapidly, and a well-developed uterus appears abruptly after it is barely visible in a previous proglottid. In S. parvissima the uterus grows gradually, and its early development is seen in several proglottids. At the level of pre-gravid proglottids the uterus of S. gulyaevi n. sp. occupies only the middle field of the proglottid, while in S. parvissima it fills the whole proglottid including lateral fields. The rostellar hooks in the new species are significantly smaller in size than in S. asketus. Additionally, the new species has fewer proglottids than S. asketus, while having a similar strobila length. Molecular comparison, using 3 genes (28s rDNA, cox1, and nad1), between S. gulyaevi n. sp. and S. parvissima, further corroborates the status of S. gulyaevi n. sp. as a new species. The new species is the seventh species of Staphylocystoides found in North America and the first cestode or any helminth reported from shrews in southeast Alaska. PMID:23919726

Greiman, Stephen E; Tkach, Vasyl V; Cook, Joseph A

2013-12-01

247

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

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

Darmani, Nissar A; Crim, Jennifer L

2005-01-01

248

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

PubMed

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

McAfee, Robert K

2011-10-01

249

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

NASA Astrophysics Data System (ADS)

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).

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

2007-01-01

250

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

PubMed Central

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

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

2012-01-01

251

A new species of coccidia (Apicomplexa: Eimeriidae) from Cordillera striped shrew-rat, Chrotomys whiteheadi (Rodentia: Muridae), from the Philippines.  

PubMed

During July 2011, a single Cordillera striped shrew-rat (Chrotomys whiteheadi) was collected from the Philippines and its faeces examined for coccidian parasites. It harboured an eimerian that we describe here as new. Oocysts of Eimeria macarthuri sp. n. were spheroidal to subspheroidal with a bi-layered wall and measured (length × width, L × W) 18.2 × 17.0 ?m, with an L/W ratio of 1.1. A micropyle, oocyst residuum and polar granule were absent. Sporocysts were ovoidal, 9.0 × 6.4 ?m, with an L/W ratio of 1.3. A nipple-like Stieda body was present as well as a substieda body. A granular sporocyst residuum was present. To our knowledge, E. macarthuri represents the only coccidian ever described from a rodent of the Philippines. PMID:25236280

McAllister, Chris T; Seville, R Scott; Duszynski, Donald W; Bush, Sarah E

2014-10-01

252

A new hantavirus from the stripe-backed shrew (Sorex cylindricauda) in the People's Republic of China.  

PubMed

Inspired by the recent discovery of genetically distinct hantaviruses from insectivore species worldwide, we performed a small-scale search for insectivore-borne hantaviruses. In this paper, we report the discovery of a new hantavirus, which was designated the Qian Hu Shan virus (QHSV). This virus was detected in the lung tissues of three stripe-backed shrews (Sorex cylindricauda), which were captured in the Yunnan Province, China. The full-length S genomic segment of the representative QHSV strain YN05-284 was 1661 nucleotides and is predicted to encode a nucleocapsid protein of 429 amino acids that starts at nucleotide position 48. It exhibited the highest similarity with other Sorex-related hantaviruses, with 68.1%-72.8% nucleotide and 71.9%-84.4% amino acid sequence identities. An analysis of a 1430-nucleotide region of the partial M segment exhibited approximately 54.4%-79.5% nucleotide and 43.2%-90.8% amino acid sequence identities to other hantaviruses. A comparison of a 432-nucleotide region of the L segment also showed similar degrees of identity, with 68.9%-78.4% nucleotide and 71.1%-93.8% amino acid sequence identities to other hantaviruses. Phylogenetic analyses using Bayesian methods indicated that QHSV shared the most recent common ancestor with other Sorex-related hantaviruses. The host was identified using a morphological assessment and verified using mitochondrial cytochrome b (mt-Cyt b) gene sequencing. A pair-wise comparison of the 1140-nucleotide mt-Cyt b gene sequence from the host demonstrated that the host was close to S. cylindricauda from Nepal with 94.3% identity. The virus-host association tanglegram, which was constructed using the Dendroscope software, indicated that the QHSV phylogeny and the host phylogeny were approximately matched, which suggests no evidence of host switching for QHSV. Our results contribute to a wider viewpoint regarding the heterogeneity of viruses that infect shrews. PMID:24553099

Zuo, Shu-Qing; Gong, Zheng-Da; Fang, Li-Qun; Jiang, Jia-Fu; Zhang, Jiu-Song; Zhao, Qiu-Min; Cao, Wu-Chun

2014-05-12

253

The X-autosome translocation in the common shrew ( Sorex araneus L.): late replication in female somatic cells and pairing in male meiosis  

Microsoft Academic Search

Common shrews have an XX\\/XY1Y2 sex chromosome system, with the “X” chromosome being a translocation (tandem fusion) between the “original” X and an autosome; in males this autosome is represented by the Y2 chromosome. From G-banded chromosomes, the Y2 is homologous to the long arm and centromeric part of the short arm of the X. The region of the X

Svetlana D. Pack; Pavel M. Borodin; Oleg L. Serov; Jeremy B. Searle

1993-01-01

254

Brevinema andersonii gen. nov., sp. nov., an infectious spirochete isolated from the short-tailed shrew (Blarina brevicauda) and the white-footed mouse (Peromyscus leucopus).  

PubMed

A spirochete which infects short-tailed shrews (Blarina brevicauda) and white-footed mice (Peromyscus leucopus) has been shown previously to be ultrastructurally and serologically distinct from other spirochetes. Two of the original isolates from Connecticut and Minnesota and 16 new isolates obtained from shrews captured in Minnesota were characterized phenotypically and genetically in this study. A comparative analysis of the 16S rRNA sequences of two shrew isolates and one mouse isolate and the 16S rRNA sequences of 16 other spirochetes and Escherichia coli revealed that these organisms exhibited low levels of similarity (range of similarity values, 73.9 to 77.8%; average level of similarity, 74.7%). The shrew and mouse isolates which we examined formed a deeply branching subgroup that was clearly distinct from the other genera of spirochetes examined. These and other results indicated that the new spirochetes represent a unique taxon in the order Spirochaetales. Accordingly, we propose that they should be classified as members of a new genus, Brevinema. The three strains of Brevinema which we examined had 16S rRNA sequences that were nearly identical. We also compared these isolates by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, fatty acid and enzyme analyses, restriction endonuclease analysis, and Southern hybridization and found that the levels of genetic and phenotypic homogeneity among the strains were very high. We concluded that the isolates which we examined were members of a single species, for which we propose the name Brevinema andersonii. The type strain of Brevinema andersonii is CT11616 (= ATCC 43811).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7857811

Defosse, D L; Johnson, R C; Paster, B J; Dewhirst, F E; Fraser, G J

1995-01-01

255

Soricid response to forest stand age in southern Appalachian cove hardwood communities  

Microsoft Academic Search

Monthly from May 1994 until April 1995, we examined four age classes (15, 25, 50, and > 85 years old) of southern Appalachian cove hardwood stands in the Chattahoochee National Forest of Georgia to determine the effects of even-aged forest management (clearcutting) on the relative abundance of shrews (Insectivora: Soricidae). Stands were sampled using drift-fence\\/pitfall trap methodologies. During 60 060

William M. Ford; Joshua Laerm; Katherine G. Barker

1997-01-01

256

Is there an association of Pneumocystis infection with the presence of arena-, hanta-, and poxvirus antibodies in wild mice and shrews in Finland?  

PubMed

As part of studies on the nature of the endemic virus infections in natural rodent hosts, the possible association of cyst forms of Pneumocystis spp. with the presence of hanta-, cowpox-, and arenavirus antibodies in wild mice (Apodemus flavicollis, N=105; Apodemus agrarius, N=63; Micromys minutus, N=50) and the common shrew (Sorex araneus, N=101) was studied in south-central Finland. One hantavirus (Saaremaa virus, SAAV) seropositive A. agrarius, and 2 cowpoxvirus (CPXV) seropositive S. araneus were detected, and antibodies against an arenavirus (Lymphocytic choriomeningitis virus, LCMV) were found in all 3 mouse species but not in shrews. Cyst forms of Pneumocystis spp. were detected in all species except A. agrarius. There was no significant association between virus antibodies (LCMV in mice, and CPXV in shrews) and cyst forms of Pneumocystis in any of the species. Concurrent presence of virus antibodies (LCMV) and cyst forms of Pneumocystis were detected only in 1 M. minutus. In conclusion, we found no evidence of any association between Pneumocystis and antibodies to any of the viruses tested. PMID:16556344

Laakkonen, J; Kallio, E R; Kallio-Kokko, H; Vapalahti, O; Vaheri, A; Henttonen, H

2006-04-01

257

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

USGS Publications Warehouse

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.

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

1998-01-01

258

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

PubMed

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

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

2007-06-01

259

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

PubMed Central

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

Siegwart, John T.; Norton, Thomas T.

2007-01-01

260

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

PubMed Central

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

Siegwart, John T.; Norton, Thomas T.

2007-01-01

261

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

PubMed Central

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

2013-01-01

262

Blarina toxin, a mammalian lethal venom from the short-tailed shrew Blarina brevicauda: Isolation and characterization.  

PubMed

Venomous mammals are rare, and their venoms have not been characterized. We have purified and characterized the blarina toxin (BLTX), a lethal mammalian venom with a tissue kallikrein-like activity from the submaxillary and sublingual glands of the short-tailed shrew Blarina brevicauda. Mice administered BLTX i.p. developed irregular respiration, paralysis, and convulsions before dying. Based on the amino acid sequence of purified protein, we cloned the BLTX cDNA. It consists of a prosequence and an active form of 253 aa with a typical catalytic triad of serine proteases, with a high identity with tissue kallikreins. BLTX is an N-linked microheterogeneous glycoprotein with a unique insertion of 10 residues, L(106)TFFYKTFLG(115). BLTX converted kininogens to kinins, which may be one of the toxic pathogens, and had dilatory effects on the blood vessel walls. The acute toxicity and proteolytic activity of BLTX were strongly inhibited by aprotinin, a kallikrein inhibitor, suggesting that its toxicity is due to a kallikrein-like activity of the venom. PMID:15136743

Kita, Masaki; Nakamura, Yasuo; Okumura, Yuushi; Ohdachi, Satoshi D; Oba, Yuichi; Yoshikuni, Michiyasu; Kido, Hiroshi; Uemura, Daisuke

2004-05-18

263

Fiber type distribution in the shoulder muscles of the tree shrew, the cotton-top tamarin, and the squirrel monkey related to shoulder movements and forelimb loading.  

PubMed

Muscle fiber type composition of intrinsic shoulder muscles was examined in tree shrews, cotton-top tamarins, and squirrel monkeys with respect to their shoulder kinematics and forelimb loading during locomotion. Enzyme- and immunohistochemical techniques were applied to differentiate muscle fiber types on serial cross-sections of the shoulder. In the majority of the shoulder muscles, the proportions of fatigue resistant slow-twitch fibers (SO) and fatigable fast-twitch fibers (FG) were inversely related to each other, whereas the percentage of intermediate FOG-fibers varied independently. A segregation of fatigue resistant SO-fibers into deep muscle regions is indicative of differential activation of histochemically distinct muscle regions in which deep regions stabilize the joint against gravitational loading. In all three species, this antigravity function was demonstrated for both the supraspinatus and the cranial subscapularis muscle, which prevent passive joint flexion during the support phase of the limb. The infraspinatus muscle showed a high content of SO-fibers in the primate species but not in the tree shrew, which demonstrates the "new" role of the infraspinatus muscle in joint stabilization related to the higher degree of humeral protraction in primates. In the tree shrew and the cotton-top tamarin, a greater proportion of the body weight is carried on the forelimb, but the squirrel monkey exhibits a weight shift to the hind limbs. The lower amount of forelimb loading is reflected by an overall lower proportion of fatigue resistant muscle fibers in the shoulder muscles of the squirrel monkey. Several muscles such as the deltoid no longer function as joint stabilizers and allow the humerus to move beyond the scapular plane. These differences among species demonstrate the high plasticity of the internal muscle architecture and physiology which is suggested to be the underlying reason for different muscle activity patterns in homologous muscles. Implications for the evolution of new locomotor modes in primates are discussed. PMID:17289114

Schmidt, Manuela; Schilling, Nadja

2007-04-01

264

Splenic mass of masked shrews, Sorex cinereus, in relation to body mass, sex, age, day of the year, and bladder nematode, Liniscus (=Capillaria) maseri, infection.  

PubMed

The spleen is an important organ of vertebrates. Splenic mass can change in response to a variety of factors. We tested whether splenic mass of masked shrews, Sorex cinereus, was related to sex, age, time of the year, or intensity of bladder nematode (Liniscus [=Capillaria] maseri) infection, after controlling for host body mass. For females, body mass was a strong predictor of splenic mass. For males, splenic masses were greater later in the year and in more heavily infected males. The latter appeared to represent a threshold response wherein only the most heavily infected individuals had enlarged spleens. PMID:18576853

Cowan, Krystyna M; Shutler, Dave; Herman, Thomas B; Stewart, Donald T

2009-02-01

265

Physiological characteristics of gastric contractions and circadian gastric motility in the free-moving conscious house musk shrew (Suncus murinus).  

PubMed

Although many studies have demonstrated the physiological action of motilin on the migrating motor complex, the precise mechanisms remain obscure. To obtain new insights into the mechanisms, we focused on the house musk shrew (Suncus murinus, suncus used as a laboratory name) as a small model animal for in vivo motilin study, and we studied the physiological characteristics of suncus gastrointestinal motility. Strain gauge transducers were implanted on the serosa of the gastric body and duodenum, and we recorded gastrointestinal contractions in the free-moving conscious suncus and also examined the effects of intravenous infusion of various agents on gastrointestinal motility. During the fasted state, the suncus stomach and duodenum showed clear migrating phase III contractions (intervals of 80-150 min) as found in humans and dogs. Motilin (bolus injection, 100-300 ng/kg; continuous infusion, 10-100 ng·kg(-1)·min(-1)) and erythromycin (80 ?g·kg(-1)·min(-1)) induced gastric phase III contractions, and motilin injection also increased the gastric motility index in a dose-dependent manner (P < 0.05, vs. saline). Pretreatment with atropine completely abolished the motilin-induced gastric phase III contractions. On the other hand, in the free-feeding condition, the suncus showed a relatively long fasting period in the light phase followed by spontaneous gastric phase III contractions. The results suggest that the suncus has almost the same gastrointestinal motility and motilin response as those found in humans and dogs, and we propose the suncus as a new small model animal for studying gastrointestinal motility and motilin in vivo. PMID:20686171

Sakahara, Satoshi; Xie, Zuoyun; Koike, Kanako; Hoshino, Satoya; Sakata, Ichiro; Oda, Sen-ichi; Takahashi, Toku; Sakai, Takafumi

2010-10-01

266

Thalamic Burst Firing Propensity: a Comparison of the Dorsal Lateral Geniculate and Pulvinar Nuclei in the Tree Shrew  

PubMed Central

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 over 70% of recorded neurons. Using immunohistochemistry, western blot techniques, unbiased stereology, confocal and electron microscopy, we found that pulvinar neurons expressed more T-type calcium channels (Cav 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

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

2011-01-01

267

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

PubMed Central

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

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

2013-01-01

268

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

PubMed

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

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

2012-08-15

269

Genetic diversity of Imjin virus in the Ussuri white-toothed shrew (Crocidura lasiura) in the Republic of Korea, 2004-2010  

PubMed Central

Recently, Imjin virus (MJNV), a genetically distinct hantavirus, was isolated from lung tissues of the Ussuri white-toothed shrew (Crocidura lasiura) captured near the demilitarized zone in the Republic of Korea. To clarify the genetic diversity of MJNV, partial M- and L-segment sequences were amplified from lung tissues of 12 of 37 (32.4%) anti-MJNV IgG antibody-positive Ussuri white-toothed shrews captured between 2004 and 2010. A 531-nucleotide region of the M segment (coordinates 2,255 to 2,785) revealed that the 12 MJNV strains differed by 0-12.2% and 0-2.3% at the nucleotide and amino acid levels, respectively. A similar degree of nucleotide (0.2-11.9%) and amino acid (0-3.8%) difference was found in a 632-nucleotide length of the L segment (coordinates 962 to 1,593) of nine MJNV strains. Phylogenetic analyses, based on the partial M and L segments of MJNV strains generated by the neighbor-joining and maximum likelihood methods, showed geographic-specific clustering, akin to the phylogeography of rodent-borne hantaviruses. PMID:21303516

2011-01-01

270

Extreme environmental change and evolution: stress-induced morphological variation is strongly concordant with patterns of evolutionary divergence in shrew mandibles.  

PubMed Central

Morphological structures often consist of simpler traits which can be viewed as either integrated (e.g. correlated due to functional interdependency) or non-integrated (e.g. functionally independent) traits. The combination of a long-term stabilizing selection on the entire structure with a short-term directional selection on an adaptively important subset of traits should result in long historical persistence of integrated functional complexes, with environmentally induced variation and macroevolutionary change confined mostly to non-integrated traits. We experimentally subjected populations of three closely related species of Sorex shrews to environmental stress. As predicted, we found that most of the variation in shrew mandibular shape was localized between rather than within the functional complexes; the patterns of integration did not change between the species. The stress-induced variation was confined to nonintegrated traits and was highly concordant with the patterns of evolutionary change--species differed in the same set of non-integrated traits which were most sensitive to stress within each species. We suggest that low environmental and genetic canalization of non-integrated traits may have caused these traits to be most sensitive not only to the environmental but also to genetic perturbations associated with stress. The congruence of stress-induced and between-species patterns of variation in non-integrated traits suggests that stress-induced variation in these traits may play an important role in species divergence. PMID:10722219

Badyaev, A V; Foresman, K R

2000-01-01

271

Purification and characterisation of blarinasin, a new tissue kallikrein-like protease from the short-tailed shrew Blarina brevicauda: comparative studies with blarina toxin.  

PubMed

A new tissue kallikrein-like protease, blarinasin, has been purified from the salivary glands of the short-tailed shrew Blarina brevicauda. Blarinasin is a 32-kDa N-glycosylated protease with isoelectric values ranging between 5.3 and 5.7, and an optimum pH of 8.5 for enzyme activity. The cloned blarinasin cDNA coded for a pre-pro-sequence and a mature peptide of 252 amino acids with a catalytic triad typical for serine proteases and 43.7-54.0% identity to other mammalian tissue kallikreins. Blarinasin preferentially hydrolysed Pro-Phe-Arg-4-methylcoumaryl-7-amide (MCA) and N-tert-butyloxycarbonyl-Val-Leu-Lys-MCA, and preferentially converted human high-molecular-weight kininogen (HK) to bradykinin. The activity of blarinasin was prominently inhibited by aprotinin (K(i) =3.4 nM). A similar kallikrein-like protease, the lethal venom blarina toxin, has previously been purified from the salivary glands of the shrew Blarina and shows 67.9% identity to blarinasin. However, blarinasin was not toxic in mice. Blarinasin is a very abundant kallikrein-like protease and represents 70-75% of kallikrein-like enzymes in the salivary gland of B. brevicauda. PMID:15843162

Kita, Masaki; Okumura, Yuushi; Ohdachi, Satoshi D; Oba, Yuichi; Yoshikuni, Michiyasu; Nakamura, Yasuo; Kido, Hiroshi; Uemura, Daisuke

2005-02-01

272

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

PubMed Central

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

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

2013-01-01

273

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

PubMed Central

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

Siegwart, John T.; Norton, Thomas T.

2010-01-01

274

Neoskrjabinolepis nuda n. sp. from shrews on Sakhalin Island, Russia, with a taxonomic review of Neoskrjabinolepis Spasskii, 1947 (Cestoda: Cyclophyllidea: Hymenolepididae).  

PubMed

Neoskrjabinolepis (Neoskrjabinolepidoides) nuda n. sp. is described from the shrews Sorex unguiculatus (type-host), S. gracillimus, S. isodon and S. caecutiens on Sakhalin Island, Russia. The new species is characterised by: rostellar hooks 40-44 microm long and provided with small epiphyseal thickening of the handle; a long (95-100 microm) cirrus consisting of basal region with claw-shaped spines, a parabasal region with thin needle-shaped spines and an unarmed distal region; a cirrus-sac extending well into the median field; and 15-22 eggs per gravid uterus. A review of the species of Neoskrjabinolepis Spasskii, 1947 is presented. Currently, this genus includes nine species and is divided in two subgenera on the basis of strobilar development, which is gradual in the subgenus Neoskrjabinolepis (four species) and serial in the subgenus Neoskrjabinolepidoides Kornienko, Gulyaev & Mel'nikova, 2006 (five species). An amended generic diagnosis and an identification key to Neoskrjabinolepis spp. are presented. PMID:18427960

Kornienko, Svetlana A; Gulyaev, Vladimir D; Mel'nikova, Yulia A; Georgiev, Boyko B

2008-06-01

275

Alterations in Protein Expression in Tree Shrew Sclera during Development of Lens-Induced Myopia and Recovery  

PubMed Central

Purpose. During the development of, and recovery from, negative lens-induced myopia there is regulated remodeling of the scleral extracellular matrix (ECM) that controls the extensibility of the sclera. Difference gel electrophoresis (DIGE) was used to identify and categorize proteins whose levels are altered in this process. Methods. Two groups of five tree shrews started monocular lens wear 24 days after eye opening (days of visual experience [VE]). The lens-induced myopia (LIM) group wore a ?5 D lens for 4 days. The recovery (REC) group wore a ?5 D lens for 11 days and then recovered for 4 days. Two normal groups (28 and 39 days of VE; n = 5 each) were also examined, age-matched to each of the treatment groups. Refractive and A-scan measures confirmed the effect of the treatments. Scleral proteins were isolated and resolved by DIGE. Proteins that differed in abundance were identified by mass spectrometry. Ingenuity pathway analysis was used to investigate potential biological pathway interactions. Results. During normal development (28–39 days of VE), eight proteins decreased and one protein increased in relative abundance. LIM-treated eyes were myopic and longer than control eyes; LIM-control eyes were slightly myopic compared with 28N eyes, indicating a yoking effect. In both the LIM-treated and the LIM-control eyes, there was a general downregulation from normal of proteins involved in transcription, cell adhesion, and protein synthesis. Additional proteins involved in cell adhesion, actin cytoskeleton, transcriptional regulation, and ECM structural proteins differed in the LIM-treated eyes versus normal but did not differ in the control eyes versus normal. REC-treated eyes were recovering from the induced myopia. REC-control eye refractions were not significantly different from the 39N eyes, and few proteins differed from age-matched normal eyes. The balance of protein expression in the REC-treated eyes, compared with normal eyes and REC-control eyes, shifted toward upregulation or a return to normal levels of proteins involved in cell adhesion, cell division, cytoskeleton, and ECM structural proteins, including upregulation of several cytoskeleton-related proteins not affected during myopia development. Conclusions. The DIGE procedure revealed new proteins whose abundance is altered during myopia development and recovery. Many of these are involved in cell-matrix adhesions, cytoskeleton, and transcriptional regulation and extend our understanding of the remodeling that controls the extensibility of the sclera. Reductions in these proteins during minus lens wear may produce the increased scleral viscoelasticity that results in faster axial elongation. Recovery is not a mirror image of lens-induced myopia—many protein levels, decreased during LIM, returned to normal, or slightly above normal, and additional cytoskeleton proteins were upregulated. However, no single protein or pathway appeared to be responsible for the scleral changes during myopia development or recovery. PMID:22039233

Norton, Thomas T.

2012-01-01

276

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

PubMed Central

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

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

2011-01-01

277

Surveillance of endoparasitic infections and the first report of Physaloptera sp. and Sarcocystis spp. in farm rodents and shrews in central Taiwan.  

PubMed

A total of 95 rodents and shrews including 82 Rattus norvegicus, 7 Rattus rattus, and 6 Suncus murinus were trapped from different localities of Taichung, Taiwan. The overall prevalence of parasites was 93.7%. The infection rates for R. norvegicus, R. rattus, and S. murinus were 93.9%, 85.7%, and 100%, respectively. The rats were infected with four cestodes, Taenia taeniaeformis (48.4%), Hymenolepis diminuta (38.9%), Hymenolepis nana (5.3%), and Raillietina celebensis (45.3%); ten nematodes, Angiostrongylus cantonensis (16.8%), Capillaria hepatica (49.5%), Gongylonema neoplasticum (1.1%), Heterakis spumosa (35.8%), Nippostrongylus brasiliensis (57.9%), Physaloptera sp. (1.1%), Strongyloides ratti (81.1%), Syphacia muris (2.1%), Trichosomoides crassicauda (29.5%), and Trichurus sp. (1.1%), and one protozoan, Sarcocystis spp. (33.7%). Physaloptera sp. from S. murinus and Sarcocystis spp. from both R. norvegicus and R. rattus were reported for the first time in Taiwan. The importances of zoonotic species were discussed. PMID:19194075

Tung, Kwong-Chung; Hsiao, Fun-Chun; Yang, Cheng-Hsiung; Chou, Chi-Chung; Lee, Wei-Ming; Wang, Kai-Sung; Lai, Cheng-Hung

2009-01-01

278

Synaptonemal complex analysis of interracial hybrids between the Moscow and Neroosa chromosomal races of the common shrew Sorex araneus showing regular formation of a complex meiotic configuration (ring-of-four)  

PubMed Central

Abstract Immunocytochemical and electron microscopic analysis of synaptonemal complexes (SCs) was carried out for the first time in homozygotes and complex Robertsonian heterozygotes (hybrids) of the common shrew, Sorex araneus Linnaeus, 1758, from a newly discovered hybrid zone between the Moscow and the Neroosa chromosomal races. These races differ in four monobrachial homologous metacentrics, and closed SC tetravalent is expected to be formed in meiosis of a hybrid. Indeed, such a multivalent was found at meiotic prophase I in hybrids. Interactions between multivalent and both autosomes and/or the sex chromosomes were observed. For the first time we have used immunocytochemical techniques to analyse asynapsis in Sorex araneus and show that the multivalent pairs in an orderly fashion with complete synapsis. Despite some signs of spermatocytes arrested in the meiotic prophase I, hybrids had large number of active sperm. Thus, Moscow – Neroosa hybrid males that form a ring-of-four meiotic configuration are most likely not sterile. Our results support previous demonstrations that monobrachial homology of metacentrics of the common shrew does not lead to complete reproductive isolation between parapatric chromosomal races of the species. PMID:24260670

Matveevsky, Sergey N.; Pavlova, Svetlana V.; Maret M. Acaeva; Oxana L. Kolomiets

2012-01-01

279

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

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 II? (Ca2+/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 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 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 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 CaMKII? and ERK1/2, which contribute to the 5-HT3R-mediated, 2-Me-5-HT-evoked emesis. PMID:25121483

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

2014-01-01

280

The historical biogeography of Mammalia  

PubMed Central

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

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

2011-01-01

281

The historical biogeography of Mammalia.  

PubMed

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

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

2011-09-12

282

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

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

Ray, Andrew P.; Darmani, Nissar A.

2009-01-01

283

Evolutionary Insights from a Genetically Divergent Hantavirus Harbored by the European Common Mole (Talpa europaea)  

PubMed Central

Background The discovery of genetically distinct hantaviruses in shrews (Order Soricomorpha, Family Soricidae) from widely separated geographic regions challenges the hypothesis that rodents (Order Rodentia, Family Muridae and Cricetidae) are the primordial reservoir hosts of hantaviruses and also predicts that other soricomorphs harbor hantaviruses. Recently, novel hantavirus genomes have been detected in moles of the Family Talpidae, including the Japanese shrew mole (Urotrichus talpoides) and American shrew mole (Neurotrichus gibbsii). We present new insights into the evolutionary history of hantaviruses gained from a highly divergent hantavirus, designated Nova virus (NVAV), identified in the European common mole (Talpa europaea) captured in Hungary. Methodology/Principal Findings Pair-wise alignment and comparison of the full-length S- and L-genomic segments indicated moderately low sequence similarity of 54–65% and 46–63% at the nucleotide and amino acid levels, respectively, between NVAV and representative rodent- and soricid-borne hantaviruses. Despite the high degree of sequence divergence, the predicted secondary structure of the NVAV nucleocapsid protein exhibited the characteristic coiled-coil domains at the amino-terminal end, and the L-segment motifs, typically found in hantaviruses, were well conserved. Phylogenetic analyses, using maximum-likelihood and Bayesian methods, showed that NVAV formed a distinct clade that was evolutionarily distant from all other hantaviruses. Conclusions Newly identified hantaviruses harbored by shrews and moles support long-standing virus-host relationships and suggest that ancestral soricomorphs, rather than rodents, may have been the early or original mammalian hosts. PMID:19582155

Kang, Hae Ji; Bennett, Shannon N.; Sumibcay, Laarni; Arai, Satoru; Hope, Andrew G.; Mocz, Gabor; Song, Jin-Won; Cook, Joseph A.; Yanagihara, Richard

2009-01-01

284

Reproduction in the arctic shrew, Sorex arcticus  

E-print Network

with or replaced the dominant species. Litter provided dense cover throughout the year. Microtus pennsylvanicus was the most common small mammal taken throughout the study. For details on the vegetation, climate, soils, and other mammals of the management area.... 1980. Dispersal in meadow voles, Mi- crotus pennsylvanicus. Unpubl. Ph.D. dissert., Univ. Minnesota, Minneapolis, 111 pp. BAIRD, D. D., AND E. C. BIRNEY. 1982. Character- istics of dispersing meadow voles Microtus penn- sylvanicus. Amer. Midland...

Baird, Donna Day; Timm, Robert M.; Nordquist, Gerda E.

1983-05-01

285

Blood parasites of shrews from Pennsylvania.  

PubMed

We examined 30 Sorex cinereus, 5 Sorex fumeus, and 21 Blarina brevicauda collected from Pennsylvania in 1995 for blood parasites. Trypomastigotes of Trypanosoma sp. were visible in 13% of the S. cinereus. Ten percent of S. cinereus, 20% of S. fumeus, and 14% of B. brevicauda were infected with Bartonella sp. (or spp.). In S. cinereus, we detected no concurrent Trypanosoma and Bartonella infections. PMID:9920338

Laakkonen, J; Haukisalmi, V; Merritt, J F

1998-12-01

286

Automating analog design: Taming the shrew  

NASA Technical Reports Server (NTRS)

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.

Barlow, A.

1990-01-01

287

LUNG PARASITES OF SHREWS FROM PENNSYLVANIA  

Microsoft Academic Search

ABSTRA(:T: We exarnimied lmmngparasites of three species of soricids, Sore.? cinereus (ii = 58), Sorexfirneus (in = 23) and Blarina brevicauda (in = 45) collected from Penmnsvhvania (USA), fromnn 1990 to 1995. Yeast-like cells of Histoplasina capsulatuin var. capsulatuin were found innInning sections stained with Grocott's nnnodificationof Gonnnori's mniethenamnnine silver,periodic acid-Schiff, Giemnisa, and hematoxylin-eosin in two (3%) S. cinereus, eight

Juha Laakkonen; Voitto Haukisalmi; Joseph F. Merritt

288

Arthritis in a Glyptodont (Mammalia, Xenarthra, Cingulata)  

PubMed Central

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

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

2014-01-01

289

EVOLUTIONARY RELATIONSHIPS IN MACROTUS (MAMMALIA: CHIROPTERA) : BIOCHEMICAL  

E-print Network

- vespertilionid bats, Pipistrellus hsperus edge of changing patterns of genotype and Myotis californicus were of the New World populations of Myotis velifer (a vesper- leaf-nosed bats of the genus Macrotus by tilionid estimates of of Macrotus californicus (a phyllostomatid genic heterozygosity in vertebrate popula- #12

Baker, Robert J.

290

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

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

Wallis, Michael

2008-01-15

291

Proceedings of the South Dakota Academy of Science,Vol. 81 (2002) 147 VARIATION IN SMALL MAMMAL RICHNESS AMONG  

E-print Network

) (38%), short- tailed shrews (Blarina brevicauda) (38%), masked shrews (Sorex cinereus) (12%), meadow, ecotypes, masked shrew, Peromyscus maniculatus, short-tailed shrew, small mammals, Sorex cinerus

292

Molecular evidence for multiple origins of Insectivora and for a new order of endemic African insectivore mammals  

PubMed Central

The traditional views regarding the mammalian order Insectivora are that the group descended from a single common ancestor and that it is comprised of the following families: Soricidae (shrews), Tenrecidae (tenrecs), Solenodontidae (solenodons), Talpidae (moles), Erinaceidae (hedgehogs and gymnures), and Chrysochloridae (golden moles). Here we present a molecular analysis that includes representatives of all six families of insectivores, as well as 37 other taxa representing marsupials, monotremes, and all but two orders of placental mammals. These data come from complete sequences of the mitochondrial 12S rRNA, tRNA-Valine, and 16S rRNA genes (2.6 kb). A wide range of different methods of phylogenetic analysis groups the tenrecs and golden moles (both endemic to Africa) in an all-African superordinal clade comprised of elephants, sirenians, hyracoids, aardvark, and elephant shrews, to the exclusion of the other four remaining families of insectivores. Statistical analyses reject the idea of a monophyletic Insectivora as well as traditional concepts of the insectivore suborder Soricomorpha. These findings are supported by sequence analyses of several nuclear genes presented here: vWF, A2AB, and ?-? hemoglobin. These results require that the order Insectivora be partitioned and that the two African families (golden moles and tenrecs) be placed in a new order. The African superordinal clade now includes six orders of placental mammals. PMID:9707584

Stanhope, Michael J.; Waddell, Victor G.; Madsen, Ole; de Jong, Wilfried; Hedges, S. Blair; Cleven, Gregory C.; Kao, Diana; Springer, Mark S.

1998-01-01

293

[First record of Van sung's shrew (Chodsigoa caovansunga) in China].  

PubMed

On December 5, 2012, a specimen of Chodsigoa caovansunga Lunde, Musser and Son, 2003 was collected at Manhao, Gejiu, Yunnan (N23Degrees Celsius00'43.0'', E103Degrees Celsius26'18.9'', 350 m asl). This finding is the first recorded distribution of C. caovansunga in China and outside of the type locality (Mt. Tay Con Linh II, Ha Giang, Vietnam). The length of the head, body, tail and condylo-incisive are longer than those of the specimens from type locality in Vietnam, indicating a generally larger size. Likewise, the cyt-b sequence (GenBank accession number: JX508288) is 98.6% similar to specimens from type locality. The habitat of collection site was a ravine rain forest with banana plantation nearby. PMID:23019038

He, Kai; Deng, Ke; Jiang, Xue-Long

2012-10-01

294

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

ERIC Educational Resources Information Center

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)

Williams, Michael

1990-01-01

295

Epidemiology of Bartonella infection in rodents and shrews in Taiwan.  

PubMed

During the period of August 2002 and November 2004, an epidemiological investigation for Bartonella infection was conducted in small mammals in Taiwan. Using whole blood culture on chocolate agar plates, Bartonella species were successfully isolated from 41.3% of the 310 animals tested. The isolation rate of Bartonella species varied among different animal species, including 52.7% of the 169 Rattus norvegicus, 28.6% of the 126 Sucus murinus, 10% of the 10 Rattus rattus and 66.7% of the three Rattus losea. Bacteremia prevalence also varied with the origin of the animals, as 56.2% of the animals captured on farms, 38.6% of the ones captured at harbour sites and 11.8% of the animals captured from urban areas were bacteremic. Through molecular analysis of the gltA gene and 16S/23S intergenic spacer region, genetic diversity of Bartonella organisms was identified, including strains closely related to Bartonella tribocorum, Bartonella grahamii, Bartonella elizabethae, Bartonella phoceensis and Bartonella rattimassiliensis. Moreover, this is the first report of zoonotic B. elizabethae and B. grahamii identified in R. losea, the lesser rice-field rat. Various Bartonella species were identified in R. norvegicus, compared to 97.2% of Suncus murinus with unique Bartonella species. By indirect immunofluorescence antibody test, using various rodent Bartonella species as antigens, consistently low percentage of seropositivity implied that small mammals may play a role as competent reservoirs of Bartonella species in Taiwan. Future studies need to be conducted to determine whether these Bartonella species would be responsible for human cases of unknown fever or febrile illness in Taiwan, especially zoonotic B. elizabethae and B. grahamii. PMID:19538457

Hsieh, J-W; Tung, K-C; Chen, W-C; Lin, J-W; Chien, L-J; Hsu, Y-M; Wang, H-C; Chomel, B B; Chang, C-C

2010-09-01

296

HABITS OF THE SHORT-TAILED SHREW, BLARINA BREVICAUDA (SAY)  

Microsoft Academic Search

The following notes are presented in the hopes that they may be of interest to students of the smaller mammals. The observations submitted here have been made over a period of six years, commencing in 1924 and continued as time permitted. MOLTING. Molting appears to take place without regard to season, and specimens taken in December and June alike show

W. J. HAMILTON

297

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

PubMed

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

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

2002-11-01

298

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

PubMed Central

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

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

2002-01-01

299

Blarina hylophaga (Soricomorpha: Soricidae) CODY W. THOMPSON, JERRY R. CHOATE*, HUGH H. GENOWAYS, AND ELMER J. FINCK  

E-print Network

, subfamily Soricinae, tribe Blarinini (Hutterer 2005; Repenning 1967). The genus Blarina includes 4 species-sized species of the genus Blarina (Choate et al. 1994; Jones et al. 1985; Jones and Birney 1988; Jones

Hayssen, Virginia

300

BIOLOGICAL EVOLUTION Origin and Evolution of Animals  

E-print Network

Acanthodii Chondrichthyes Osteichthyes Amphibia Reptilia Mammalia Aves Fossil record of vertebrates #12;Mammalia Reptilia Aves Amphibia Osteichthyes Acantodii Placodermi Chondrichthyes Agnatha Sarcopterygii

Cooper, Brenton G.

301

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

NASA Astrophysics Data System (ADS)

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.

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

2008-09-01

302

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

Microsoft Academic Search

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

Karen D. Stone; Joseph A. Cook

2002-01-01

303

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

PubMed

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

Stone, Karen D; Cook, Joseph A

2002-08-01

304

Odobenocetops peruvianus, the Walrus-Convergent Delphinoid (Mammalia: Cetacea)  

E-print Network

.C. 20560-0121, and LaboratoJ)' o/Evolutionary Biology, Department ofAnatomy, College of }vledicine, Howard as orientation guides for the mouth and vibrissal array. Introduction Abundant remains of fossil odontocete cetaceans have been found in the rocks of the Pisco Formation near the southern coast of Peru. Although

305

Catalogue of Fossil Mammalia in the British Museum, Part I  

Microsoft Academic Search

IN the review of the above work in a late number of NATURE (vol. xxxi. p. 597) the reviewer entertains such a complete misapprehension of my system of naming the premolar teeth of typical heterodont Eutherian mammals that I must beg space to correct it.

Richard Lydekker

1885-01-01

306

Evolutionary morphology of the Tenrecoidea (Mammalia) hindlimb skeleton.  

PubMed

The tenrecs of Central Africa and Madagascar provide an excellent model for exploring adaptive radiation and functional aspects of mammalian hindlimb form. The pelvic girdle, femur, and crus of 13 tenrecoid species, and four species from the families Solenodontidae, Macroscelididae, and Erinaceidae, were examined and measured. Results from qualitative and quantitative analyses demonstrate remarkable diversity in several aspects of knee and hip joint skeletal form that are supportive of function-based hypotheses, and consistent with studies on nontenrecoid eutherian postcranial adaptation. Locomotor specialists within Tenrecoidea exhibit suites of characteristics that are widespread among eutherians with similar locomotor behaviors. Furthermore, several characters that are constrained at the subfamily level were identified. Such characters are more indicative of postural behavior than locomotor behavior. PMID:19107938

Salton, Justine A; Sargis, Eric J

2009-03-01

307

Postcanine Dental Form in the Mustelidae and Viverridae (Carnivora: Mammalia)  

E-print Network

with diet. The fourth upper premolar (P4 ) and the first lower molar (M1) form the carnivoran carnassial teeth that prim- itively contain elongated shearing surfaces, whereas the more posterior molars on the molars. On the other hand, loss of shearing function and emphasis of crushing surfaces reaches an ex

Meyers, Ron

308

Evolution of chromosomal variation in cottontails, genus Sylvilagus (Mammalia: Lagomorpha)  

Microsoft Academic Search

Chromosomes from cultured fibroblasts of four cottontail species (Sylvilagus audubonii, 2n = 42; S. idahoensis, 2n = 44; S. nuttallii, 2n = 42; and S. palustris, 2n = 38) were analyzed using G- and C-banding techniques. The evolutionary restructuring of the genomes of these species was traced by comparing their banded chromosomes to those of Lepus saxatilis, a species of

T. J. Robinson; F. F. B. Elder; J. A. Chapman

1984-01-01

309

RNA Interference in Mammalia Cells by RNA-3'-PNA Chimeras  

PubMed Central

The discovery of siRNAs as the mediators of RNA interference has led to an increasing interest in their therapeutic applications. Chemical modifications are introduced into siRNAs to optimize the potency, the stability and the pharmacokinetic properties in vivo. Here, we synthesize and test the effects of RNA-3’-PNA chimeras on siRNA functioning and stability. We demonstrate that the chemical modifications are compatible with the siRNA machinery, because all the PNA-modified siRNAs can efficiently mediate specific gene silencing in mammalian cells. Furthermore, we find that the modification on the sense strand of siRNA results in an increased persistence of the activity, whereas modification on both strands results in enhanced nuclease resistance in serum. PMID:19325750

Potenza, Nicoletta; Moggio, Loredana; Milano, Giovanna; Salvatore, Vincenzo; Di Blasio, Benedetto; Russo, Aniello; Messere, Anna

2008-01-01

310

Investigacin, Biodiversidad y Desarrollo MAMMALIA, CHIROPTERA, PHYLLOSTOMIDAE, Lonchophylla pattoni  

E-print Network

, Colombia. 3. Programa de Biología con �nfasis en Recursos Naturales, Universidad Tecnológica del Chocó, Quibdó, Colombia. e-mail: almajior@hotmail.com Fecha de recibido: Enero 1, 2009 Fecha de aprobación peninsular projection (Figure 2); broadly inflated pterygoid process; deep basis- phenoidpits

Baker, Robert J.

311

Shared Ancestry between a Newfound Mole-Borne Hantavirus and Hantaviruses Harbored by Cricetid Rodents ?†  

PubMed Central

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

Kang, Hae Ji; Bennett, Shannon N.; Hope, Andrew G.; Cook, Joseph A.; Yanagihara, Richard

2011-01-01

312

rIc. IL1 Dorsalvicw ofskulls of(A) round-earcd elephant-shrew (Maloslides proboscdeus) and (B) castern rock elephant-shrew (Elephantulus myuns)  

E-print Network

on the substrate' In the wild, foot-drumming occurs during agonistic encounters, when the animal is agitated, and $en it "rr.'orr-rrt.tt a predator (Rathbun, 1979; Roeper, 1981)' This drumming is emitted in a series of one or more bouts, each bout consisting"of one or more foot drums, usually 25-50 ms apart' F'2ch

313

Response to Interrupted Hyperopia after Restraint of Axial Elongation in Tree Shrews  

PubMed Central

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

Siegwart, John T.; Norton, Thomas T.

2012-01-01

314

LowRate TCPTargeted Denial of Service Attacks (The Shrew vs. the Mice and Elephants) y  

E-print Network

and kills much larger animals with a venomous bite. Permission to make digital or hard copies of all or part be detected, the attacker identified, and the effects of the attack mitigated (see for example, [6, 22, 30), typically 10's to 100's of msec, TCP performs additive­increase multiplicative­decrease (AIMD) control

Knightly, Edward W.

315

Species interactions during diversification and community assembly in an island radiation of shrews.  

E-print Network

support through DEB 0743491 and 0640737 to RMB and Graduate Research and International Postdoctoral (OISE 0965856) fellowships to JAE. Additional financial support was provided by the American Society of Mammalogists and E. Raymond Hall Fund... primarily across geographic barriers with little change in ecologically important traits, competition has the potential to prevent speciation, by limiting the ability of individual species to expand over barriers into the range of other, closely related...

Brown, Rafe M.

2011-01-01

316

The origin of the Osorian shrew (Crocidura osorio) from Gran Canaria resolved using mtDNA  

Microsoft Academic Search

Crocidura osorio was first described in 1989 as an endemic species confined to the islands of Gran Canaria and (possibly) Tenerife. However phenotypic differences between C. osorio and other species are small leading to doubts over its taxonomic status. This is resolved using mtDNA. Over 1120 base pairs from the cytochrome b and 16S rRNA regions of the mtDNA of

Obdulia Molina; Richard P. Brown; Nicolás M. Suárez; José J. Pestano

2003-01-01

317

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...

318

RANGE EXTENSION AND NOTES ON THE SHREW SOREX CINEREUS IN OHIO  

Microsoft Academic Search

In the course of trapping old fields on 3, 4, and 5 December 1962, fifteen Sorex cinereus were caught in Butler Township, Mercer County, 1.6 miles north of the town of Coldwater, Ohio. This is an extension 85 miles to the southwest of the range for the species in Ohio. Included are reproductive data, weights, and measurements, as well as

JACK L. GOTTSCHANG

319

Noradrenalin induces thermogenesis in a phylogenetically ancient eutherian mammal, the rock elephant shrew, Elephantulus myurus  

Microsoft Academic Search

The evolution of endothermy is thought to have been facilitated by the advent of endothermic energy sources such as brown\\u000a adipose tissue (BAT), the principal site of non-shivering thermogenesis (NST). In marsupials, heat is primarily produced through\\u000a shivering and NST in skeletal muscle because BAT is either absent or appears to be non-functional. The most basal group of\\u000a the eutherian

Nomakwezi Mzilikazi; Barry G. Lovegrove

2006-01-01

320

Flying lemurs - the "flying tree shrews"? Molecular cytogenetic evidence for a Scandentia-Dermoptera sister clade  

E-print Network

, Rodentia, Carnivora). Proc Biol Soc Wash 2003, 116:699-709. 64. Nie W, Wang J, O'Brien PCM, Fu B, Tian Y, Ferguson-Smith MA, Yang F: The genome phylogeny of domestic cat, red panda and five mustelid species revealed by comparative chromosome painting and G... , Ferguson-Smith MA: A complete compara- tive chromosome map for the dog, red fox and human and its integration with canine genetic maps. Genomics 1999, 62:189-202. 39. Robinson TJ, Fu B, Ferguson-Smith MA, Yang F: Cross-species chromosome painting...

Nie, Wenhui; Fu, Beiyuan; O'Brien, Patricia C M; Wang, Jinhuan; Su, Weiting; Tanomtong, Alongklod; Volobouev, Vitaly; Ferguson-Smith, Malcolm A; Yang, Fengtang

2008-05-01

321

The use of albendazole for the treatment of trematodiasis in two tree shrews (Tupala glis)  

USGS Publications Warehouse

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.

Beehler, B.A.; Tuggle, B.N.

1983-01-01

322

Evolutionary biogeography of water shrews (Neomys spp.) in the western Palaearctic Region  

E-print Network

body size, fringes of stiff hairs bordering the hind foot, and a tail keel) were most developed in N to the evolutionary biogeography of Anatolian Turkey and vice-versa. We here report the results of investigations

Davison, Angus

323

Morphological diversity and ecological similarity: versatility of muscular and skeletal morphologies enables ecological convergence in shrews  

Microsoft Academic Search

Summary 1. Ecological convergence in morphology among taxa of distinct evolutionary histories is a common illustration of the efficacy of natural selection. Ecological convergence is often enabled by functional redundancy of complex morphological structures, such that modification of existing morphologies in response to similar functional requirements can lead to the devel- opment and evolution of morphological diversity. Thus, studies of

Rebecca L. Young; Michael J. Sweeney; Alexander V. Badyaev

2009-01-01

324

Food of Vagrant Shrews (Sorex vagrans) Irom Grant County, Oregon, as Relaled to Livestock Grazing Pressures  

Microsoft Academic Search

Maior foods of the vagrant shrcat (Sorcx ltagrdnt) in a relatively non-gtazed potior of a mountain meadow itr Grant County wete earthworms, spiders, crickets, caterpillars, moths, slugs and snails. and Juoe beetles and their larvae. ln two similat areas subjected to greater recent grazing, flightless lorms (except caterpillars) were much less used; tbey were replaced primarily by caterpillars and flying

John O. Whitake; Stephen P. Cross; Chris Maserl

1983-01-01

325

DOI 10.1515/mammalia-2011-0138Mammalia 2013; 77(1): 2130 Arielle Waldstein Parsons*, Theodore R. Simons, Allan F. O'Connell Jr. and  

E-print Network

of an isolated, unmanaged raccoon Procyon lotor (Procyonidae, Carnivora) population on the Outer Banks of North Carolina Abstract: Raccoons (Procyon lotor) are highly adapt- able meso-carnivores that inhabit many-carnivore; Procyon lotor; raccoon. *Corresponding author: Arielle Waldstein Parsons, US Geological Survey, North

Simons, Theodore R.

326

Inferring host specificity and network formation through agent-based models: tick-mammal interactions in Borneo.  

PubMed

Patterns of host-parasite association are poorly understood in tropical forests. While we typically observe only snapshots of the diverse assemblages and interactions under variable conditions, there is a desire to make inferences about prevalence and host-specificity patterns. We studied the interaction of ticks with non-volant small mammals in forests of Borneo. We inferred the probability of species interactions from individual-level data in a multi-level Bayesian model that incorporated environmental covariates and advanced estimates for rarely observed species through model averaging. We estimated the likelihood of observing particular interaction frequencies under field conditions and a scenario of exhaustive sampling and examined the consequences for inferring host specificity. We recorded a total of 13 different tick species belonging to the five genera Amblyomma, Dermacentor, Haemaphysalis, Ixodes, and Rhipicephalus from a total of 37 different host species (Rodentia, Scandentia, Carnivora, Soricidae) on 237 out of 1,444 host individuals. Infestation probabilities revealed most variation across host species but less variation across tick species with three common rat and two tree shrew species being most heavily infested. Host species identity explained ca. 75 % of the variation in infestation probability and another 8-10 % was explained by local host abundance. Host traits and site-specific attributes had little explanatory power. Host specificity was estimated to be similarly low for all tick species, which were all likely to infest 34-37 host species if exhaustively sampled. By taking into consideration the hierarchical organization of individual interactions that may take place under variable conditions and that shape host-parasite networks, we can discern uncertainty and sampling bias from true interaction frequencies, whereas network attributes derived from observed values may lead to highly misleading results. Multi-level approaches may help to move this field towards inferential approaches for understanding mechanisms that shape the strength and dynamics in ecological networks. PMID:23108423

Wells, Konstans; O'Hara, Robert B; Pfeiffer, Martin; Lakim, Maklarin B; Petney, Trevor N; Durden, Lance A

2013-06-01

327

Geographic and host range of the nematode Soboliphyme baturini across Beringia.  

PubMed

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

Koehler, Anson V A; Hoberg, Eric P; Dokuchaev, Nikolai E; Cook, Joseph A

2007-10-01

328

Comparative anatomy and systematic implications of the turbinal skeleton in lagomorpha (mammalia).  

PubMed

In order to elucidate the systematic relevance of the turbinal skeleton in Lagomorpha the ethmoidal regions of 6 ochotonid, 21 leporid, and 2 outgroup species (Sciurus vulgaris, Tupaia sp.) species were investigated by high-resolution computed tomography (?CT). Number and shape of turbinals correspond to major clades and to several genera. All Lagomorpha under study have a deeply excavated nasoturbinal that is continuous with the lamina semicircularis; a feature likely to be an autapomorphy of lagomorphs. In particular, the olfactory turbinals (frontoturbinals, ethmoturbinals, and interturbinals) provide new systematic information. The plesiomorphic lagomorph pattern comprises two frontoturbinals, three ethmoturbinals, and one interturbinal between ethmoturbinal I and II. Ochotonidae are derived from the lagomorph goundplan by loss of ethmoturbinal III; an interturbinal between the two frontoturbinals is an autapomorphy of Leporidae. Pronolagus is apomorphic in having a very slender first ethmoturbinal, but shows a puzzling pattern in decreasing the number of turbinals. Pronolagus rupestris and Romerolagus diazi have independently reduced their turbinals to just two fronto- and two ethmoturbinals, which is the lowest number among the sampled lagomorphs. In contrast, the more derived leporid genera under study (Oryctolagus, Caprolagus, Sylvilagus, and Lepus) show a tendency to increase the number of turbinals, either by developing an ethmoturbinal IV (Caprolagus hispidus, Lepus arcticus) or by additional interturbinals. Intraspecific variation was investigated in Ochotona alpina, Oryctolagus cuniculus, and Lepus europaeus and is restricted to additional interturbinals in the frontoturbinal recess of the two leporids. Anat Rec, 297:2031-2046, 2014. © 2014 Wiley Periodicals, Inc. PMID:25312363

Ruf, Irina

2014-11-01

329

Chromosome painting among Proboscidea, Hyracoidea and Sirenia: Support for Paenungulata (Afrotheria, Mammalia) but not Tethytheria  

USGS Publications Warehouse

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.

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

330

Sphiggurus vestitus pruinosus (Mammalia, Rodentia, Erethizontidae): The Karyotype and its Phylogenetic Implications, Descriptive Notes  

Microsoft Academic Search

Sphiggurus vestitus pruinosus, a porcupine from western Venezuela, has a karyotype with a diploid number (2n) of 42, and a fundamental number (FN) of 76. The autosomes consist of 34 metacentric and submetacentric, 2 subacrocentric, and 4 acrocentric chromosomes. The X?chromosome is submetacentric, and the Y?chromosome is acrocentric. This karyotype is identical in gross morphology to that of the North

J. L. Concepcion; J. Molinari

1991-01-01

331

Rhinocerotidae (Mammalia) from the Late Miocene of Bulgaria DENIS GERAADS, Paris, and NIKOLA SPASSOV, Sofia  

E-print Network

kiliasi, a species for which a new sub-genus, Eochilotherium, is established. Some fragmentary remains is well represented at Kalimantsi, but this genus probably deserves revision. An unexpected discovery, as it is unlikely that the main fossil faunas are very different in age. It also reflects the geographic position

Paris-Sud XI, Université de

332

Digital dissection of the masticatory muscles of the naked mole-rat, Heterocephalus glaber (Mammalia, Rodentia)  

PubMed Central

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

Faulkes, Chris G.

2014-01-01

333

A new middle eocene whale (Mammalia: Cetacea: Archaeoceti) and associated biota from Georgia  

USGS Publications Warehouse

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.

Hulbert, R.C., Jr.; Petkewich, R.M.; Bishop, G.A.; Bukry, D.; Aleshire, D.P.

1998-01-01

334

Philodryas chamissonis (Reptilia: Squamata: Colubridae) preys on the arboreal marsupial Dromiciops gliroides (Mammalia: Microbiotheria: Microbiotheriidae).  

PubMed

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 Chillán, 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

Muñoz-Leal, S; Ardiles, K; Figueroa, R A; González-Acuña, D

2013-02-01

335

Paroodectes feisti , der erste Miacide (Carnivora, Mammalia) aus dem Mittel-Eozän von Messel  

Microsoft Academic Search

\\u000a Abstract  From the Middle Eocene (Lower Lutetian) Oil Shale of Messel near Darmstadt (South-Hesse) the first completely preserved Miacid\\u000a is described. The systematic position of the Miacidae is discussed before. A short review of the paleogeographic (North-America,\\u000a Eurasia) and stratigraphic (L. Paleocene — U. Eocene, ? U. Oligocene) distribution is given; the fossil record of European\\u000a species is more detailed. The

Rainer Springhorn

1980-01-01

336

Late Cenozoic History of the Genus Micromys (Mammalia, Rodentia) in Central Europe  

PubMed Central

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 Csarnóta 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

Horacek, Ivan; Knitlova, Marketa; Wagner, Jan; Kordos, Laszlo; Nadachowski, Adam

2013-01-01

337

DNA Profiling of B Chromosomes from the Yellow-necked Mouse Apodemus flavicollis (Rodentia, Mammalia)  

PubMed Central

Using AP-PCR-based DNA profiling we examined some structural features of B chromosomes from yellow-necked mice Apodemus flavicollis. Mice harboring one, two, or three or lacking B chromosomes were examined. Chromosomal structure was scanned for variant bands by using a series of arbitrary primers and from these, informative bands were selected. The selection criteria used were the ability to differentiate between individuals of the species, to detect markers common for both A and B chromosomes, and, importantly, to differentiate between A- and B-chromosome sets. In addition to primers, profiling conditions were found to be critical for meeting the selection criteria. Primers and analysis conditions that demonstrated structural characteristics unique to the B-chromosome set are described. These characteristics included variant bands as qualitative parameters and altered electrophoretic band intensities as quantitative distinctions estimated by integration of densitometric profiles of electrophoretograms. B chromosome-specific molecular markers are easy to detect by AP-PCR-based DNA profiling in the presence of a full set of A chromosomes. Models for the origin of yellow-necked mouse B chromosomes are discussed in the context of presented data. PMID:10645950

Tani?, Nikola; Dedovi?, Nasta; Vujos?evi?, Mladen; Dimitrijevi?, Bogomir

2000-01-01

338

Definition, Diagnosis, and Origin of Mammalia Author(s): Timothy Rowe  

E-print Network

Paleontology, Vol. 8, No. 3 (Sep. 23, 1988), pp. 241-264 Published by: The Society of Vertebrate Paleontology Paleontology is collaborating with JSTOR to digitize, preserve and extend access to Journal of Vertebrate Paleontology. http://www.jstor.org #12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;#12;

Sullivan, Jack

339

Didymoconus (Mammalia: Didymoconidae) from Lanzhou Basin, China and its stratigraphic and ecological significance  

Microsoft Academic Search

A partial skull and lower jaw with associated postcranial skeleton of Didymoconus berkeyi Matthew and Granger, 1924 was recently collected from the late Oligocene of Lanzhou Basin, Gansu Province, China. Besides being the first discovery of this genus in the Lanzhou Basin, the new material of Didymoconus represents the most complete individual of this species. The new specimen is paleomagnetically

Xiaoming Wang; William Downs; Junyi Xie; Guangpu Xie

2001-01-01

340

Review and analysis of the radiation of the south American Hystricognathi (Mammalia, Rodentia)  

NASA Astrophysics Data System (ADS)

The fossil record of the first genera of each family of South American Hystricognathi rodents is reviewed. On this basis the main events for the radiation of the infraorder on this continent are recognized. Two main events can be identified: the first occurs probably during the Eocene-Oligocene boundary, and the second at the Middle-Late Miocene boundary.

Guiomar Vucetich, Marìa; Verzi, Diego H.; Hartenberger, Jean-Louis

1999-11-01

341

Mandible shape and dwarfism in squirrels (Mammalia, Rodentia): interaction of allometry and adaptation  

NASA Astrophysics Data System (ADS)

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.

Hautier, Lionel; Fabre, Pierre-Henri; Michaux, Jacques

2009-06-01

342

Description de la radiation des Rodentia (Mammalia) du Paléocène supérieur au Miocène; incidences phylogénétiques  

NASA Astrophysics Data System (ADS)

Reviewing the ancestor-descendant relationships of first genera representatives of 52 fossil and extant families of rodents allow the building of a phylogenetic tree of Rodentia. The shaping of this tree suggests the distribution of these families in six suborders and six infraorders.

Hartenberger, Jean-Louis

1998-03-01

343

Dental microwear patterns of extant and extinct Muridae (Rodentia, Mammalia): ecological implications  

NASA Astrophysics Data System (ADS)

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 Saïdomys 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.

Gomes Rodrigues, Helder; Merceron, Gildas; Viriot, Laurent

2009-04-01

344

First Castorid (Mammalia, Rodentia) from the Middle Miocene of Southeast Asia  

NASA Astrophysics Data System (ADS)

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.

Suraprasit, Kantapon; Chaimanee, Yaowalak; Martin, Thomas; Jaeger, Jean-Jacques

2011-04-01

345

Placentation and fetal membrane development in the South American coati, Nasua nasua (Mammalia, Carnivora, Procyonidae)  

PubMed Central

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

2014-01-01

346

Home range and social behavior of three species of European Pitymys (Mammalia, Rodentia)  

Microsoft Academic Search

Habits, home range, and social behavior of three species of voles of the genus Pitymys, P. multiplex, P. subterraneus, and P. savii, were studied in Tessin (Switzerland) by radioactive tagging. P. multiplex and P. savii are fossorial and often use the burrow systems of moles (Talpa); P. subterraneus moves around on the surface under dense vegetation. Males and females of

Marco Salvioni

1988-01-01

347

Phylogeographic Patterns and Evolution of the Mitochondrial DNA Control Region in Two Neotropical Cats (Mammalia, Felidae)  

Microsoft Academic Search

.   The ocelot (Leopardus pardalis) and margay (L. wiedii) are sister-species of Neotropical cats which evolved from a lineage that migrated into South America during the formation\\u000a of the Panamanian land bridge 3–5 million years ago. Patterns of population genetic divergence of each species were studied\\u000a by phylogenetic analyses of mitochondrial DNA (mtDNA) control region sequences in individuals sampled across

Eduardo Eizirik; Sandro L. Bonatto; Warren E. Johnson; Peter G. Crawshaw Jr.; Jean Cristophe Vié; Dulce M. Brousset; Stephen J. O'Brien; Francisco M. Salzano

1998-01-01

348

First record of Dinofelis (Felidae, Mammalia) from North Africa Denis GERAADS  

E-print Network

dorsally by a forward extension of the supramastoid crest, stretching under the external auditory meatus tooth fragments, and a skull fragment with the auditory region, including the petrosal. Description (FALCONER & CAUTLEY, 1836, Figs. 1-2, reproduced in Werdelin & Lewis, 2001, Fig. 33). The auditory region

Paris-Sud XI, Université de

349

Earliest record of rhinocerotoids (Mammalia: Perissodactyla) from Switzerland: systematics and biostratigraphy  

Microsoft Academic Search

Earliest rhinocerotoids from Switzerland are reviewed on the basis of dental remains from the earliest Oligocene north-central\\u000a Jura Molasse localities of Bressaucourt (MP21\\/22) and Kleinblauen (top MP22). The record in Bressaucourt is restricted to\\u000a Ronzotherium and Cadurcotherium, representing Switzerland’s oldest, well-dated post-“Grande Coupure” large mammal association, the only occurrence of Cadurcotherium, and the earliest occurrence of rhinocerotoids in Switzerland. The

Damien Becker

2009-01-01

350

Island history affects faunal composition: the treeshrews (Mammalia: Scandentia: Tupaiidae) from the  

E-print Network

coast of Sumatra have a complicated geological and biogeographical history. The Batu Islands have shared, 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

Olson, Link

351

New remains of Astraponotus (Mammalia, Astrapotheria) and considerations on Astrapothere cranial evolution  

Microsoft Academic Search

Astraponotus Ameghino, 1901, the only valid Mustersan (late Eocene) astrapothere, typifies the Ameghino’s “Capas Astraponotenses”. This taxon is traditionally interpreted as structurally ancestral to all the Oligocene–Miocene astrapotheriids. However,\\u000a it was imperfectly known: only isolated teeth and very partial mandibles have hitherto been described. In this contribution\\u000a we provide the first description of the skull, mandible, and complete dentition of

Alejandro G. Kramarz; Mariano Bond; Analia M. Forasiepi

2011-01-01

352

Geometric morphometric study of the skull shape diversification in Sciuridae (Mammalia, Rodentia).  

PubMed

It is generally accepted that the high phenotypic diversity of mammals is a combined result of developmental constraint and ecological adaptation, although the influence of these endogenous and exogenous factors varies in different mammal groups. The rodent family Sciuridae represents an ideal candidate for examining phenotypic diversity in relation to phylogeny and ecological adaptations. In the present study, we investigate the effects of phylogeny and lifestyle on the skull shape in different species of Sciuridae by applying geometric morphometric methods. In addition, we investigate the importance of allometry on sciurid skull shape, because results from geometric morphometrics sometimes dispute those of traditional morphometry. Here, we identify significant associations between patristic distances obtained from molecular phylogeny and shape distances in all 3 views of the cranium and the lateral view of the mandible. Multivariate regression demonstrates that shape differences among lifestyle categories are substantial, especially in the dorsal and ventral structures after the influence of phylogeny is taken into account. Allometry plays an important role in the shape variation, although its importance on different skull structures varies. Our results indicate that complex structures of this highly diverse mammal group, which occupies different niches, are affected by ecological factors and developmental constraint. PMID:24952964

Lu, Xuefei; Ge, Deyan; Xia, Lin; Huang, Chengming; Yang, Qisen

2014-06-01

353

Phenotypic Convergence in Genetically Distinct Lineages of a Rhinolophus Species Complex (Mammalia, Chiroptera)  

PubMed Central

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

Jacobs, David S.; Babiker, Hassan; Bastian, Anna; Kearney, Teresa; van Eeden, Rowen; Bishop, Jacqueline M.

2013-01-01

354

A new species of Murina (Mammalia: Chiroptera: Vespertilionidae) from peninsular Thailand.  

PubMed

A new species of Murina belonging to 'suilla-group' is described based on two specimens collected with harp traps in lowland evergreen forest in the southernmost part of peninsular Thailand. Morphology and molecular (mitochondrial COI) data suggest that the new species is most closely related to M. eleryi, which is currently known from Indochina. The new species, however, can be distinguished by the size and shape of the upper canine, the shape of the upper and lower premolars, and the colour of the ventral pelage. Additional data on bacular morphology, echolocation, ecology, and distribution are included. PMID:25113497

Soisook, Pipat; Karapan, Sunate; Satasook, Chutamas; Bates, Paul J J

2013-01-01

355

Bats (Mammalia: Chiroptera) in native and reforested areas in Rancho Alegre, Paraná, Brazil.  

PubMed

Abstract: Generally, natural environments have been transformed into small forest remnants, with the consequent habitat loss and species extinction. The North Paraná State is not an exception, since only 2 to 4% of the original ecosystem occurs in small fragments of Stational Semidecidual Forest. We studied the species richness and abundance of bats in two forest fragments from the Fazenda Congonhas, in Rancho Alegre city, Parana State, Brazil. Four samplings were undertaken in a legally protected native area (107.8 ha) and in a reforested area (11.8 ha) between April 2007 and March 2008. Samplings began at nightfall and lasted six hours,during two consecutive nights in each location. The individuals were captured using eight mist nets, with the same capture effort in both environments. A total of 397 individuals, 14 species and 10 genera were captured in the native area; while in the reforested area, 105 individuals, six species and four genera. Artibeus lituratus was the most common species in both fragments (n = 328, 65.3%), followed by Artibeus fimbriatus (n = 44, 8.8%) and Artibeus jamaicensis (n = 30, 6.0%). Other species including Platyrrhinus lineatus, Carollia perspicillata, Sturnira lilium, Chrotopterus aurintus, Desmodus rotundus, Michronycteris megalotis, Phyllostomus hastatus, Phyllostomus discolor, Myoti levis, Myotis nigricans and Lasiurus blossevillii, accounted for 19.9% of the captures. The native area presented higher values of species richness (S = 14) and diversity (H' = 1.4802) in comparison to the reforested area (S = 6, H '= 0.57015). The t-test evidenced a significant difference between diversity among the sites (t = 7.1075). Chao 1 index indicated that the sampling effort recorded approximately 78% from the total species richness for the native area and 75% for the reforested area. Therefore, the preservation of the forest fragment is essential since it provides habitat for a diverse community of bats. Forest management and reforestation actions may prevent drastic changes in the microclimate of neighboring areas within the forest fragment, and could allow the occupation of available niches in the area, by opportunistic and generalist species. PMID:21246993

Gallo, Patricia Helena; dos Reis, Nelio Roberto; Andrade, Fabio Rodrigo; de Almeida, Inaê Guion

2010-12-01

356

First detailed reconstruction of the karyotype of Trachypithecus cristatus (Mammalia: Cercopithecidae)  

PubMed Central

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

2013-01-01

357

The evolution of fossoriality and the adaptive role of horns in the Mylagaulidae (Mammalia: Rodentia)  

PubMed Central

Ceratogaulus, a member of the extinct fossorial rodent clade Mylagaulidae, is the only known rodent with horns and the smallest known horned mammal. The function of the large, dorsally projecting nasal horns on this burrowing animal has been the subject of wide speculation among palaeontologists; suggested uses range from sexual combat to burrowing. Mammals have evolved adaptations for digging repeatedly; horns and other cranial appendages have also evolved numerous times. These two adaptations co-occur in mammals extremely rarely: only two fossil genera (Ceratogaulus and the xenarthran Peltephilus) and no extant mammals are both horned and fossorial. Tracing the evolution of fossoriality in aplodontoid rodents (the larger clade to which Ceratogaulus belongs) reveals that Ceratogaulus descended from ancestors who dug by head-lifting. Whereas this suggests an obvious explanation for the horns of this rodent, evidence from functional morphology, anatomy, phylogeny and geologic context indicates that the horns in Ceratogaulus were used for defence, rather than digging, and evolved to offset increased predation costs associated with spending more time foraging above ground as body size increased. PMID:16087426

Hopkins, Samantha S.B

2005-01-01

358

A new immigrant mustelid (Carnivora, Mammalia) from the middle Miocene Temblor Formation of central California  

E-print Network

of Vertebrate Paleontology, Natural History Museum of LosHistory, Wash- ington, DC, USA UCMP: University of California Museum of Paleontology,Paleontology in Berkeley, California. Comparative materials are housed at the Natural History

Tseng, Zhijie Jack; Wang, Xiaoming; Stewart, J. D.

2009-01-01

359

NEW CHALICOTHERIIDAE (PERISSODACTYLA, MAMMALIA) FROM THE LATE MIOCENE OF DENIS GERAADS  

E-print Network

of Paleontology (Branch of the National Museum of Natural History, Sofia), ASSENOVGRAD, Bulgaria Running title; 2 National Museum of Natural History, 1, Tsar Osvoboditel blvd, 1000 SOFIA, Bulgaria; 3 Museum, published in "Journal of Vertebrate Paleontology 21, 3 (2001) 596-606" #12;2 ABSTRACT-Few fossils have been

Paris-Sud XI, Université de

360

NEW CRANIAL AND POSTCRANIAL REMAINS OF LATE PALEOCENE PLESIADAPIDAE ("PLESIADAPIFORMES," MAMMALIA) FROM NORTH  

E-print Network

Professor of Paleontology, Professor of Geology, Biology, and Anthropology, Director of Museum of Paleontology, University of Michigan, Ann Arbor This dissertation is accepted by the Graduate School Lawrence. An understanding of plesiadapid evolutionary history is important for investigations into the origin of extant

Boyer, Doug M.

361

Patterns of postnatal development in skulls of lynxes, genus Lynx (Mammalia: Carnivora).  

PubMed

Studies on ossification patterns and other ontogenetic events associated with postnatal cranial growth of wild felids are scarce. An analysis of developmental processes undergone by several cranial structures (presphenoidal and sphenooccipital synchondroses, temporal and sagittal crests, and deciduous and permanent teeth) during postnatal growth has been conducted on a sample of 336 specimens belonging to the four Recent species of lynxes (Lynx pardinus, Lynx lynx, Lynx rufus, and Lynx canadensis). Age has been estimated based on tooth replacement, skull size, and by counting the annual lines of cementum growth. Comparison of the results obtained for each of the four species reveal (1) a single pattern for both tooth replacement and ossification of the sphenooccipital synchondrosis, (2) two ossification patterns for the presphenoidal synchondrosis, (3) a common pattern for development of temporal ridges and sagittal crest showing different degrees of morphological expression, and (4) evidence suggesting the involvement of a heterochronic process, neoteny, in the morphological differentiation of several populations and species of the genus Lynx. These data also support the hypothesis that processes involved in the replacement of carnassials are based on functional requirements. PMID:8765807

Garcia-Perea, R

1996-09-01

362

Europolemur kelleri n. sp. von Messel und ein Nachtrag zu Europolemur koenigswaldi (Mammalia, Primates, Notharctidae, Cercamoniinae)  

Microsoft Academic Search

Kurzfassung  Als achter Primatenfund aus Messel wird ein vollständiger Schädel beschrieben. Nach Größe und Morphologie bezieht er sich\\u000a auf eine neue Art,Europolemur kelleri n. sp. Zu dieser Art sind auch zwei aus Messel bereits beschriebene Skelettfragmente, jeweils Becken, Baculum und Hinterextremitäten\\u000a umfassend (Koenigswald 1979, 1985), sowie eine rechte Vorderextremität aus Zeugo- und Autopodium (Franzen 1988) zu rechnen. In einem Nachtrag werden

Jens Lorenz Franzen

2000-01-01

363

A study on Morphology and Karyology of Prometheomys schaposchnikowi Satunin, 1901 (Mammalia: Rodentia) in Turkey  

Microsoft Academic Search

Karyological, morphological, bacular and phallic aspects of Prometheomys schaposchnikowi were examined based on 22 specimens collected in Ardanuç and Ardahan. The diploid number of chromosomes is 2n=56, the number of autosomal arms is NFa=100, and the fundamental number is NF=104, the X chromosome is a large submetacentric, and the Y chromosome is the smallest metacentric. In adults, sagittal crest begins

Ercüment ÇOLAK

364

The Morphological Analysis of Mus domesticus and Mus macedonicus (Mammalia: Rodentia) in Turkey  

Microsoft Academic Search

We examined 529 specimens of Mus domesticus and Mus macedonicus from Turkey, in terms of their morphological, bacular, and phallic aspects. The zygomatic index (ZI) varied from 0.32 to 0.47 in M. domesticus, and 0.60 to 0.85 in M. macedonicus. The head plus body length\\/tail length (H+B\\/T) index varied from 0.87 to 1.05 in M. domesticus, and 1.08 to 1.78

Ercüment ÇOLAK; Mustafa SÖZEN; Reyhan ÇOLAK; Tolga KANKILIÇ

365

A new species of long-eared bat (Plecotus; Vespertilionidae, Mammalia) from Ethiopia  

Microsoft Academic Search

A new species of Plecotus is described, based on several specimens from southern Ethiopia, the southernmost distribution record of the genus. The new species differs from all known species of Plecotus in size, cranial proportions and pelage coloration. In some metric and qualitative traits (skull size and face shape) it resembles P. auritus. The similarities between these two species may

Sergey V. Kruskop; Leonid A. Lavrenchenko

366

Phylogeny and divergence of the pinnipeds (Carnivora: Mammalia) assessed using a multigene dataset  

PubMed Central

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

Higdon, Jeff W; Bininda-Emonds, Olaf RP; Beck, Robin MD; Ferguson, Steven H

2007-01-01

367

Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae).  

PubMed

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

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

368

First castorid (mammalia, rodentia) from the middle miocene of southeast Asia.  

PubMed

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. PMID:21360164

Suraprasit, Kantapon; Chaimanee, Yaowalak; Martin, Thomas; Jaeger, Jean-Jacques

2011-04-01

369

Late cenozoic history of the genus Micromys (mammalia, rodentia) in Central Europe.  

PubMed

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 Csarnóta 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

Horá?ek, Ivan; Knitlová, Markéta; Wagner, Jan; Kordos, László; Nadachowski, Adam

2013-01-01

370

Evolutionary Relationships between Cranial Shape and Diet in Bats (Mammalia: Chiroptera)  

Microsoft Academic Search

The trophic radiation of new world phyllostomid bats has often been cited as an example of an explosive adaptive radiation. However, among Old World bats a similar radiation into diverse feeding niches such as frugivory, carnivory, insectivory and nectarivory has occurred. Previous analyses of cranial shape in dietary specialists have indicated general trends in cranial shape that seemed to be

Victor Van Cakenberghe; Anthony Herrel; Luis F. Aguirre

371

Chromosomes of some squirrels (mammalia — sciuridae) from the genera Sciurus and Glaucomys  

Microsoft Academic Search

Zusammenfassung Die Analyse der mitotischen Chromosomen beiSciurus carolinensis, S. niger undS. aberti ergibt die diploide Zahl 40 und gleichartige Karyotypen.S. griseus, 2n 40, hat einzigeY Chromosomen und sekundäre Konstriktionen in 4 Autosomen.Glaucomys sabrinus undG. volans, 2n 48, zeigten kleinere Unterschiede der Karyotypen. Taxonomische Bezeichnungen vonSciurus, Glaucomys undTamiasciurus werden erörtert.

C. F. Nadler; D. A. Sutton

1967-01-01

372

A time-calibrated species-level phylogeny of bats (Chiroptera, Mammalia)  

PubMed Central

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

Agnarsson, Ingi; Zambrana-Torrelio, Carlos M.; Flores-Saldana, Nadia Paola; May-Collado, Laura J.

2011-01-01

373

Human Origins and Evolution Humans belong to the Order Primates within the Class Mammalia  

E-print Network

prosimians, clockwise from right: a slow loris; an aye-aye; a ring-tailed lemur How to tell Haplorhine if they are found in the Americas New World monkeys may have prehensile (grabbing) tails; Old World monkeys never do Apes all lack tails!! Family Tarsiidae: Tarsiers New World Monkeys Above: tamarins Below: marmosets #12

Brown, Christopher A.

374

Morphometric study of phylogenetic and ecologic signals in procyonid (mammalia: carnivora) endocasts.  

PubMed

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. Anat Rec, 297:2318-2330, 2014. © 2014 Wiley Periodicals, Inc. PMID:25066912

Ahrens, Heather E

2014-12-01

375

Revision of the Wind River faunas, early Eocene of central Wyoming. X - Bunophorus (Mammalia, Artiodactyla)  

NASA Technical Reports Server (NTRS)

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.

Stucky, Richard K.; Krishtalka, Leonard

1990-01-01

376

Nucleolus organizer regions and B-chromosomes of wood mice (mammalia, rodentia, Apodemus)  

SciTech Connect

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.

Boeskorov, G.G. [Yakutia Institute of Biology, Yakutsk (Russian Federation); Kartavtseva, I.V. [Biological Soil Institute, Vladivostok (Russian Federation); Zagorodnyuk, I.V. [Shmal`gausen Institute of Zoology, Kiev (Ukraine); Belyanin, A.N. [Saratov State Univ. (Russian Federation); Lyapunova, E.A. [Kol`tsov Institute of Developmental Biology, Moscow (Russian Federation)

1995-02-01

377

Landscape correlates of the distribution of coypu Myocastor coypus (Rodentia, Mammalia) in Argentinean Pampas  

Microsoft Academic Search

The coypu is a rodent indigenous to aquatic habitats in southern South America, which is considered a pest where it has been introduced and a valuable furbearer resource within its native range. The objective of this study was to identify the main landscape correlates of coypu distribution in the Pampas. Previous studies provided two non-exclusive hypotheses: (1) if hunting pressure

L. R. Leggieri; M. L. Guichón; M. H. Cassini

2011-01-01

378

C-banded karyotype of Myocastor coypus (Molina, 1782) from Turkey (Mammalia: Rodentia).  

PubMed

The present study reports the C-band patterns of chromosomes of Myocastor coypus from Turkey. The karyotype of M. coypus is comprised of (2n) 42 chromosomes, the number of chromosomal arms (FN) was 83 and the number of autosomal arms (FNa) was 80. The X chromosome was a medium-sized metacentric and the Y chromosome was acrocentric and the smallest in the set. Two metacentric chromosomes have secondary constrictions. Most autosomes in this species were centromeric C-positive and some autosomes had telomeric C-bands. The X chromosome has centromeric heterochromatin, while the Y chromosome appeared to be entirely heterochromatic. PMID:19459458

Iliker, Ay?egül; Arslan, Atilla; Pamuko?lu, Nahit; Albayrak, Irfan

2009-01-01

379

La captura comercial del coypo Myocastor coypus (Mammalia: Myocastoridae) en Laguna Adela, Argentina  

Microsoft Academic Search

We analize commercial harvest of coypus Myocastor coypus in Laguna Adela, Argentina, during 1988. A total of 217 animals was trapped from April to October (?. = 31 per month), with a capture effort of 1768 night?traps (? = 255.57 per month). The capture increased up to a peak in August ? September and was inversely correlated with capture effort.

M. Gorostiague; H. A. Regidor

1993-01-01

380

Postcranial anatomy of Viverravus (Mammalia, Carnivora) and implications for substrate use in basal Carnivora  

Microsoft Academic Search

A postcranial skeleton of the viverravid carnivoran, Viverravus acutus from the early Eocene of Wyoming, is described and compared to contemporary carnivorans (the viverravid Didymictis, and the miacids Miacis and Vulpavus), and to extant taxa belonging to the families Mustelidae, Procyonidae, Canidae, Viverridae, and Herpestidae. Based on humeral and femoral midshaft diameters, body mass for this animal is estimated to

Ronald E. Heinrich; Peter Houde

2006-01-01

381

A new rabbit species (Sylvilagus, Mammalia: Leporidae) from the lowlands of Venezuela.  

PubMed

A new species of Venezuelan rabbit of the genus Sylvilagus from Fundo Millano (08 degrees 46'N and 69 degrees 56'W) and Chorrosco Bajo (08 degrees 05'N and 69 degrees 18'W), between 190 and 120 masl, state of Barinas, is described based on: 1. Body and skull measurements. 2. Coloration patterns of the pelage. 3. Arrangement and length of the color hair bands of dorsal, lateral, ventral nuchal, and gular patches. Body and cranial measurements, and some color patterns of the new species, Sylvilagus varynaensis, were compared with those of the closest relative groups such as S. brasiliensis (from Venezuela and Brazil), S. b. meridensis from the Venezuelan paramos, and three of the most representative groups of S. floridanus (S. f. continentis, S. f. orinoci, and S. f. valenciae). Most of the values recorded for these parameters were significantly higher for the new species (P < 0.005; Student "t" test). Cluster and principal components analysis of the data recorded for cranial characteristics indicated that S. varynaensis is the largest and darkest of the known Venezuelan rabbits, with a broader elongated skull and a different arrangement of the color hair bands. PMID:11795167

Durant, P; Guevara, M A

2001-03-01

382

An anatomical study of the brains of Dipodomys (Mammalia: Rodentia: Heteromyidae).  

PubMed

Whole brains and Nissl-stained serial sections of 3 species of kangaroo rat (Dipodomys spectabilis, D. ordii, D. merriami) were compared for interspecific differences. Neuroanatomical variations were conservative in nature. Examination of the cerebellum revealed possible differences in locomotion and ecology. Dipodomys ordii exhibited more neurological evidence for increased specialization of the hindlimbs, while D. merriami had the least differentiated cerebellar surface, thereby suggesting more stereotyped movements of the hindlimbs. Dipodomys spectabilis had abilities that lie somewhere between those of D. ordii and D. merriami. Stereological analysis demonstrated little difference in the percent of total brain volume comprising the telencephalon, diencephalon, cerebellum, and brain stem; and it revealed the relative position of the cranial nerve nuclei. PMID:507367

Dressler, J B

1979-01-01

383

Phylogeny of the Carnivora (Mammalia): congruence vs incompatibility among multiple data sets.  

PubMed

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

Flynn, J J; Nedbal, M A

1998-06-01

384

Building large trees by combining phylogenetic information: a complete phylogeny of the extant Carnivora (Mammalia).  

PubMed

One way to build larger, more comprehensive phylogenies is to combine the vast amount of phylogenetic information already available. We review the two main strategies for accomplishing this (combining raw data versus combining trees), but employ a relatively new variant of the latter: supertree construction. The utility of one supertree technique, matrix representation using parsimony analysis (MRP), is demonstrated by deriving a complete phylogeny for all 271 extant species of the Carnivora from 177 literature sources. Beyond providing a 'consensus' estimate of carnivore phylogeny, the tree also indicates taxa for which the relationships remain controversial (e.g. the red panda; within canids, felids, and hyaenids) or have not been studied in any great detail (e.g. herpestids, viverrids, and intrageneric relationships in the procyonids). Times of divergence throughout the tree were also estimated from 74 literature sources based on both fossil and molecular data. We use the phylogeny to show that some lineages within the Mustelinae and Canidae contain significantly more species than expected for their age, illustrating the tree's utility for studies of macroevolution. It will also provide a useful foundation for comparative and conservational studies involving the carnivores. PMID:10396181

Bininda-Emonds, O R; Gittleman, J L; Purvis, A

1999-05-01

385

Phylogeny of the Carnivora (Mammalia): Congruence vs Incompatibility among Multiple Data Sets  

Microsoft Academic Search

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

John J. Flynn; Michael A. Nedbal

1998-01-01

386

Discovery of the extinct red panda Parailurus (Mammalia, Carnivora) in Japan  

Microsoft Academic Search

An isolated upper fourth premolar (P4) of the extinct red panda Parailurus was recovered from the Pliocene (3–4 Ma) Ushigakubi Formation near Tochio, Niigata Prefecture, Japan. This is the first report of Parailurus from Asia, a genus previously known from Europe and northwestern North America. The Tochio P4 is about 50 percent larger than that of the extant Ailurus fulgens,

Ichiro Sasagawa; Keiichi Takahashi; Tatsuya Sakumoto; Hideaki Nagamori; Hideo Yabe; Iwao Kobayashi

2003-01-01

387

Red pandas (Mammalia, Carnivora: Parailurus ) in the biomes of North Eurasia and North America  

Microsoft Academic Search

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\\u000a with bamboo bushes were wide-spread in the Holarctic during the Neogene. During the Late Pliocene, due to a gradual cooling\\u000a of the climate, altiplanation, and other factors, their habitat started disintegrating, and

G. G. Matishov; N. P. Kalmykov

2011-01-01

388

Red pandas (Mammalia, Carnivora: Parailurus) in the biomes of North Eurasia and North America  

NASA Astrophysics Data System (ADS)

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.

Matishov, G. G.; Kalmykov, N. P.

2011-05-01

389

Building large trees by combining phylogenetic information: a complete phylogeny of the extant Carnivora (Mammalia)  

Microsoft Academic Search

One way to build larger, more comprehensive phylogenies is to combine the vast amount of phylogenetic information already available. We review the two main strategies for accomplishing this (combining raw data versus combining trees), but employ a relatively new variant of the latter: supertree construction. The utility of one supertree technique, matrix representation using parsimony analysis (MRP), is demonstrated by

OLAF R. P. BININDA-EMONDS; JOHN L. GITTLEMAN; ANDY PURVIS

1999-01-01

390

Rodents and lagomorphs (Mammalia) from the Hemphillian (late Miocene) of Utah  

USGS Publications Warehouse

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.

Korth, W.W.; De Blieux, D. D.

2010-01-01

391

Comparative morphology and evolution of the otic region in toothed whales (Cetacea, Mammalia).  

PubMed

The otic region in the skull of archeocetes and odontocetes is compared and interpreted with special emphasis on the morphology and suspension of the ear bones. In archeocetes, the periotic was obviously separate from the mastoid but still integrated within the skull via a long anterior and posterior process. The rotation of the cochlear part of the periotic was already obvious. The tympanic bone was attached to a decreasing number of neighboring elements, with the periotic becoming more and more important in the later archeocetes. The accessory air sacs of the tympanic cavity had invaded some of the adjacent skeletal elements and attained a moderate-to-remarkable extension. In the evolution of the odontocetes, the periotic and tympanic were successively uncoupled from the skull and combined to a new morphological and functional unit (tympanoperiotic complex). This uncoupling was mainly achieved by shortening the periotical processes and simultaneously extending the tympanic air sacs. For functional reasons, however, the periotic (posterior process) stayed in immediate contact with the mastoid, the latter remaining in the lateral wall of skull. In advanced marine dolphins, the bony sheaths of the accessory air sacs are largely reduced, presumably because of volume fluctuations in the tympanic cavity during diving. The perfect uncoupling of the ear bones from the skull obviously was an essential prerequisite for directional hearing, for effective ultrasound orientation and communication, and finally, for the striking development of the dolphin brain. PMID:3799488

Oelschläger, H A

1986-11-01

392

Evolutionary histories of highly repeated DNA families among the Artiodactyla (Mammalia).  

PubMed

Six highly repeated DNA families were analyzed using Southern blotting and fluorescence in situ hybridization in a comparative study of 46 species of artiodactyls belonging to seven of the eight extant taxonomic families. Two of the repeats, the dispersed bovine-Pst family and the localized 1.715 component, were found to have the broadest taxonomic distributions, being present in all pecoran ruminants (Giraffidae, Cervidae, Antilocapridae, and Bovidae), indicating that these repeats may be 25-40 million years old. Different 1.715 restriction patterns were observed in different taxonomic families, indicating that independent concerted evolution events have homogenized different motifs in different lineages. The other four satellite arrays were restricted to the Bovini and sometimes to the related Boselaphini and Tragelaphini. Results reveal that among the two compound satellites studied, the two components of the 1.711a originated simultaneously, whereas the two components of the 1.711b originated at two different historical times, perhaps as many as 15 million years apart. Systematic conclusions support the monophyly of the infraorder Pecora, the monophyly of the subfamily Bovinae (containing the Boselaphini, Bovini, and Tragelaphini), an inability to resolve any interrelationships among the other tribes of bovids, paraphyly of the genus Bos with respect to Bison, and a lack of molecular variation among two morphologically and ecologically distinct subspecies of African buffaloes (Syncerus caffer cafer and S. c. nanus). Cytogenetically, a reduction in diploid chromosome numbers through centric fusion in derived karyotypes is accompanied by a loss of centromeric satellite DNA. The nilgai karyotype contains an apparent dicentric chromosome as evidenced by the sites of 1.715 hybridization. Telomeric sequences have been translocated to the centromeres without concomitant chromosomal rearrangement in Thompson's gazelle. PMID:8661995

Modi, W S; Gallagher, D S; Womack, J E

1996-03-01

393

A Total Evidence Phylogeny of the Arctoidea (Carnivora: Mammalia): Relationships Among Basal Taxa  

Microsoft Academic Search

A total evidence phylogenetic analysis was performed for 14 extant and 18 fossil caniform genera using a data matrix of 5.6 kbp\\u000a of concatenated sequence data from six independent loci and 80 morphological characters from the cranium and dentition. Maximum\\u000a parsimony analysis recovered a single most parsimonious cladogram (MPC). The topology of the extant taxa in the MPC agreed\\u000a with previous

John A. Finarelli

2008-01-01

394

Comparative Morphology of Premolar Foramen in Lagomorphs (Mammalia: Glires) and Its Functional and Phylogenetic Implications  

PubMed Central

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

Fostowicz-Frelik, ?ucja; Meng, Jin

2013-01-01

395

Evolution and taxonomy of the wild species of the genus Ovis (Mammalia, Artiodactyla, Bovidae).  

PubMed

New insights for the systematic and evolution of the wild sheep are provided by molecular phylogenies inferred from Maximum parsimony, Bayesian, Maximum likelihood, and Neighbor-Joining methods. The phylogeny of the wild sheep was based on cytochrome b sequences of 290 samples representative of most of the sub-species described in the genus Ovis. The result was confirmed by a combined tree based on cytochrome b and nuclear sequences for 79 Ovis samples representative of the robust clades established with mitochondrial data. Urial and mouflon, which are either considered as a single or two separate species, form two monophyletic groups (O. orientalis and O. vignei). Their hybrids appear in one or the other group, independently from their geographic origin. The European mouflon O. musimon is clearly in the O. orientalis clade. The others species, O. dalli, O. canadensis, O. nivicola, and O. ammon are monophyletic. The results support an Asiatic origin of the genus Ovis, followed by a migration to North America through North-Eastern Asia and the Bering Strait and a diversification of the genus in Eurasia less than 3 million years ago. Our results show that the evolution of the genus Ovis is a striking example of successive speciation events occurring along the migration routes propagating from the ancestral area. PMID:19897045

Rezaei, Hamid Reza; Naderi, Saeid; Chintauan-Marquier, Ioana Cristina; Taberlet, Pierre; Virk, Amjad Tahir; Naghash, Hamid Reza; Rioux, Delphine; Kaboli, Mohammad; Pompanon, François

2010-02-01

396

The evolution of orbit orientation and encephalization in the Carnivora (Mammalia)  

PubMed Central

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

Finarelli, John A; Goswami, Anjali

2009-01-01

397

Electroreception and the Feeding Behaviour of Platypus (Ornithorhynchus anatinus: Monotremata: Mammalia)  

Microsoft Academic Search

It has previously been shown that platypus are sensitive to small electrical fields. It was predicted that platypus use their electrosensitivity to locate the source of foodstuffs on the bottom of the freshwater river systems in which they live, because the platypus are nocturnal, and close their eyes, ears and nostrils while underwater. In this paper we demonstrate for the

Paul R. Manger; John D. Pettigrew

1995-01-01

398

New species of Agriotherium (Mammalia, Carnivora) from the late Miocene to early Pliocene of central Myanmar  

NASA Astrophysics Data System (ADS)

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.

Ogino, Shintaro; Egi, Naoko; Zin-Maung-Maung-Thein; Thaung-Htike; Takai, Masanaru

2011-08-01

399

Phylogeography, population history and conservation genetics of jaguars (Panthera onca, Mammalia, Felidae).  

PubMed

The jaguar (Panthera onca), the largest felid in the American Continent, is currently threatened by habitat loss, fragmentation and human persecution. We have investigated the genetic diversity, population structure and demographic history of jaguars across their geographical range by analysing 715 base pairs of the mitochondrial DNA (mtDNA) control region and 29 microsatellite loci in approximately 40 individuals sampled from Mexico to southern Brazil. Jaguars display low to moderate levels of mtDNA diversity and medium to high levels of microsatellite size variation, and show evidence of a recent demographic expansion. We estimate that extant jaguar mtDNA lineages arose 280 000-510 000 years ago (95% CI 137 000-830 000 years ago), a younger date than suggested by available fossil data. No strong geographical structure was observed, in contrast to previously proposed subspecific partitions. However, major geographical barriers such as the Amazon river and the Darien straits between northern South America and Central America appear to have restricted historical gene flow in this species, producing measurable genetic differentiation. Jaguars could be divided into four incompletely isolated phylogeographic groups, and further sampling may reveal a finer pattern of subdivision or isolation by distance on a regional level. Operational conservation units for this species can be defined on a biome or ecosystem scale, but should take into account the historical barriers to dispersal identified here. Conservation strategies for jaguars should aim to maintain high levels of gene flow over broad geographical areas, possibly through active management of disconnected populations on a regional scale. PMID:11251788

Eizirik, E; Kim, J H; Menotti-Raymond, M; Crawshaw, P G; O'Brien, S J; Johnson, W E

2001-01-01

400

The first occurrence of a toxodont (Mammalia, Notoungulata) in the United States  

E-print Network

. BRYANT,2 ROLFE MANDEL,3 KENNETH J. THIES,4 and ALSTON THOMS2; 1Jackson School of Geosciences, University of Texas at Austin, Austin, Texas 78712, U.S.A., erniel@mail.utexas.edu; 2Department of Anthropology, Texas A&M University (TAMU 4352), College...

Lundelius, Ernest; Bryant, Vaughn M.; Mandel, Rolfe; Thies, Kenneth J.; Thoms, Alston

2013-01-08

401

First isolation and genotyping of Toxoplasma gondii from bats (Mammalia: Chiroptera).  

PubMed

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

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

402

Desmodus rotundus (Mammalia: Chiroptera) on the southern coast of Rio de Janeiro state, Brazil.  

PubMed

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

Costa, L M; Esbérard, C E L

2011-08-01

403

The taxonomic status of the Yucatan brown brocket, Mazama pandora (Mammalia: Cervidae)  

USGS Publications Warehouse

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.

Medellin, R.A.; Gardner, A.L.; Aranda, J.M.

1998-01-01

404

Histological patterns of the intestinal attachment of Corynosoma australe (Acanthocephala: Polymorphidae) in Arctocephalus australis (Mammalia: Pinnipedia).  

PubMed

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 Lieberkühn 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

Silva, Renato Z; Pereira, Joaber; Cousin, João Carlos B

2014-12-01

405

The mammary glands of the Amazonian manatee, Trichechus inunguis (Mammalia: Sirenia): morphological characteristics and microscopic anatomy.  

PubMed

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

Rodrigues, Fernanda Rosa; da Silva, Vera Maria Ferreira; Barcellos, José Fernando Marques

2014-08-01

406

Signature information and individual recognition in the isolation calls of Amazonian manatees, Trichechus inunguis (Mammalia: Sirenia)  

Microsoft Academic Search

Acoustic signals are assumed to form the basis of manatee communication. Empirical evidence of individual vocal recognition has been reported. If manatees can recognize one another by acoustical means, it should be possible to identify individual vocal patterns. We recorded vocalizations of 14 individually housed Amazonian manatees and then digitized selected vocalizations, allowing seven variables to be measured and subjected

Renata S. Sousa-Lima; Adriano P. Paglia; Gustavo A. B. Da Fonseca

2002-01-01

407

Molecular evolution of the mitochondrial 12S rRNA in Ungulata (mammalia).  

PubMed

The complete 12S rRNA gene has been sequenced in 4 Ungulata (hoofed eutherians) and 1 marsupial and compared to 38 available mammalian sequences in order to investigate the molecular evolution of the mitochondrial small-subunit ribosomal RNA molecule. Ungulata were represented by one artiodactyl (the collared peccary, Tayassu tajacu, suborder Suiformes), two perissodactyls (the Grevy's zebra, Equus grevyi, suborder Hippomorpha; the white rhinoceros, Ceratotherium simum, suborder Ceratomorpha), and one hyracoid (the tree hyrax, Dendrohyrax dorsalis). The fifth species was a marsupial, the eastern gray kangaroo (Macropus giganteus). Several transition/transversion biases characterized the pattern of changes between mammalian 12S rRNA molecules. A bias toward transitions was found among 12S rRNA sequences of Ungulata, illustrating the general bias exhibited by ribosomal and protein-encoding genes of the mitochondrial genome. The derivation of a mammalian 12S rRNA secondary structure model from the comparison of 43 eutherian and marsupial sequences evidenced a pronounced bias against transversions in stems. Moreover, transversional compensatory changes were rare events within double-stranded regions of the ribosomal RNA. Evolutionary characteristics of the 12S rRNA were compared with those of the nuclear 18S and 28S rRNAs. From a phylogenetic point of view, transitions, transversions and indels in stems as well as transversional and indels events in loops gave congruent results for comparisons within orders. Some compensatory changes in double-stranded regions and some indels in single-stranded regions also constituted diagnostic events. The 12S rRNA molecule confirmed the monophyly of infraorder Pecora and order Cetacea and demonstrated the monophyly of the suborder Ruminantia was not supported and the branching pattern between Cetacea and the artiodacytyl suborders Ruminantia and Suiformes was not established. The monophyly of the order Perissodactyla was evidenced, but the relationships between Artiodactyla, Cetacea, and Perissodactyla remained unresolved. Nevertheless, we found no support for a Perissodactyla + Hyracoidea clade, neither with distance approach, nor with parsimony reconstruction. The 12S rRNA was useful to solve intraordinal relationships among Ungulata, but it seemed to harbor too few informative positions to decipher the bushlike radiation of some Ungulata orders, an event which has most probably occurred in a short span of time between 55 and 70 MYA. PMID:7490777

Douzery, E; Catzeflis, F M

1995-11-01

408

Molecular systematics and phylogeography of the tribe Myonycterini (Mammalia, Pteropodidae) inferred from mitochondrial and nuclear markers.  

PubMed

The tribe Myonycterini comprises five fruit bat species of the family Pteropodidae, which are endemic to tropical Africa. Previous studies have produced conflicting results about their interspecific relationships. Here, we performed a comparative phylogeographic analysis based on 148 complete cytochrome b gene sequences from the three species distributed in West Africa and Central Africa (Myonycteris torquata, Lissonycteris angolensis and Megaloglossus woermanni). In addition, we investigated phylogenetic relationships within the tribe Myonycterini, using a matrix including 29 terminal taxa and 7235 nucleotide characters, corresponding to an alignment of two mitochondrial genes and seven nuclear introns. Our phylogenetic analyses confirmed that the genus Megaloglossus belongs to the tribe Myonycterini. Further, the genus Rousettus is paraphyletic, with R. lanosus, sometimes placed in the genus Stenonycteris, being the sister-group of the tribes Myonycterini and Epomophorini. Our phylogeographic results showed that populations of Myonycteris torquata and Megaloglossus woermanni from the Upper Guinea Forest are highly divergent from those of the Congo Basin Forest. Based on our molecular data, we recommended several taxonomic changes. First, Stenonycteris should be recognized as a separate genus from Rousettus and composed of S. lanosus. This genus should be elevated to a new tribe, Stenonycterini, within the subfamily Epomophorinae. This result shows that the evolution of lingual echolocation was more complicated than previously accepted. Second, the genus Lissonycteris is synonymised with Myonycteris. Third, the populations from West Africa formerly included in Myonycteris torquata and Megaloglossus woermanni are now placed in two distinct species, respectively, Myonycteris leptodon and Megaloglossus azagnyi sp. nov. Our molecular dating estimates show that the three phases of taxonomic diversification detected within the tribe Myonycterini can be related to three distinct decreases in tree cover vegetation, at 6.5-6, 2.7-2.5, and 1.8-1.6Ma. Our results suggest that the high nucleotide distance between Ebolavirus Côte d'Ivoire and Ebolavirus Zaire can be correlated with the Plio/Pleistocene divergence between their putative reservoir host species, i.e., Myonycteris leptodon and Myonycteris torquata, respectively. PMID:23063885

Nesi, Nicolas; Kadjo, Blaise; Pourrut, Xavier; Leroy, Eric; Pongombo Shongo, Célestin; Cruaud, Corinne; Hassanin, Alexandre

2013-01-01

409

Biochemical Systematics and Ecology 31 (2003) 739750 www.elsevier.com/locate/biochemsyseco  

E-print Network

in the following species: pygmy shrew Sorex hoyi Baird, southeastern shrew Sorex longirostris, northern short samples of pygmy shrews Sorex hoyi Baird, northern short-tailed shrews Blarina brevicauda (Say, 1823 morphologically very similar species of Blarina. The mean heterozygosity values for B. brevicauda and S. hoyi were

Sanderson, Mike

410

Low-Rate TCP-Targeted Denial of Service Attacks (The Shrew vs. the Mice and Elephants)  

E-print Network

and kills much larger animals with a venomous bite. Permission to make digital or hard copies of all or part be detected, the attacker identified, and the effects of the attack mitigated (see for example, [6, 22, 30), typically 10's to 100's of msec, TCP performs additive-increase multiplicative-decrease (AIMD) control

Kuzmanovic, Aleksandar

411

The Chronic Psychosocial Stress Paradigm in Male Tree Shrews: Evaluation of a Novel Animal Model for Depressive  

E-print Network

the most common human diseases in that approximately 11% of all adult human beings experience a time period, the stress response per se cannot be regarded as harmful or pathological in itself. Only when demanding), and a long- lasting decrease in the amplitude of the circadian patterns for heart rate and body-core

412

Effects of different land cover, habitat fragmentation, and ant colonies on the distribution and abundance of shrews in southern California  

USGS Publications Warehouse

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.

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

2001-01-01

413

The differential antiemetic properties of GLP-1 receptor antagonist, exendin (9-39) in Suncus murinus (house musk shrew).  

PubMed

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 (1 mg/kg, s.c.) and CP-99,994 (10 mg/kg, s.c) failed to reduce emesis induced by exendin-4 (3 nmol, 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 (30 mg/kg, i.p.; p < 0.05), but not the emesis induced by nicotine (5 mg/kg, s.c.; p > 0.05), or copper sulphate pentahydrate (120 mg/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

Chan, Sze Wa; Lu, Zengbing; Lin, Ge; Yew, David Tai Wai; Yeung, Chi Kong; Rudd, John A

2014-08-01

414

The emetic and anti-emetic effects of the capsaicin analogue resiniferatoxin in Suncus murinus, the house musk shrew  

PubMed Central

In Suncus murinus the ultrapotent capsaicin analogue resiniferatoxin (RTX) induced an emetic response in the dose range 1–1000??g?kg?1, s.c. The latency was inversely related to dose and ranged from 41.2±4.4?min. (1??g?kg?1, s.c.) to 2.7±0.6?min. (1000??g?kg?1, s.c.).The emetic response to RTX (10 or 100??g?kg?1, s.c.) was blocked or markedly reduced by pre-treatment with RTX (100??g?kg?1, s.c.), 8-OH-DPAT (100??g?kg?1, s.c.), morphine (2?mg?kg?1, s.c.), neonatal capsaicin (100?mg?kg?1, s.c.) and the NK1 receptor antagonist CP-99,994 (10–20?mg?kg?1, s.c.) but not by the 5-HT3 receptor antagonist tropisetron (200??g?kg?1, s.c.).RTX (100??g?kg?1, s.c.) induced c-fos-like immunoreactivity in the area postrema and parts of the nucleus tractus solitarius. This pattern is consistent with the proposal that the emetic effect is mediated via one or both of these structures and an involvement of substance P is discussed.RTX (10?and 100??g?kg?1, s.c.) had broad-spectrum antiemetic effects in Suncus as indicated by its ability to block or markedly reduce the emetic response to motion (1?Hz, 4?cm lateral, 10?min.), cisplatin (20?mg?kg?1, i.p.), intragastric copper sulphate (40?mg?kg?1, p.o.), nicotine (10?mg?kg?1, s.c.) and RTX (100??g?kg?1, s.c.) itself.It is proposed that the site of the anti-emetic effect is in the nucleus tractus solitarius and mechanisms involving the modulation of substance P release are discussed.The general utility of Suncus for investigations of vanilloid receptors is reviewed in the light of the exquisite sensitivity of the emetic reflex in this species to resiniferatoxin. PMID:10903962

Andrews, P L R; Okada, F; Woods, A J; Hagiwara, H; Kakaimoto, S; Toyoda, M; Matsuki, N

2000-01-01

415

Mitochondrial DNA variation in water shrews ( Sorex palustris , Sorex bendirii ) from western North America: implications for taxonomy and phylogeography  

Microsoft Academic Search

Inter- and intra-specific variations in cytochrome b (Cytb) sequence were assessed in 22 specimens of Sorex palustris Richardson, 1828 and 6 specimens of Sorex bendirii (Merriam, 1884) from 20 locations in western North America. Phylogenetic analyses revealed three distinct clades: Boreal (S. p. palustris), Cordilleran (S. p. brooksi, S. p. navigator), and Coastal (S. b. palmeri, S. b. bendirii). Sequence

M. B. O'Neill; D. W. Nagorsen; R. J. Baker

2005-01-01

416

Chronic psychosocial stress alters NPY system: Different effects in rat and tree shrew E. Zambello a,b,  

E-print Network

. 1. Introduction The study of the mechanisms involved in the etiology of affective disorders requires to genetic factors, which are known to predispose to psychopathologies (McGuffin and Katz, 1989), environmental stress plays an important role in the etiology of anxiety and depression, which are linked

417

State-space models for stochastic and seasonal fluctuations of vole and shrew populations in east-central Illinois  

Microsoft Academic Search

Small mammal populations fluctuate erratically and exhibit seasonal and multi-annual variations in abundance. The decomposition of population dynamics into seasonal fluctuations, stochastic trends, and residuals helps to quantify environmental stochasticity of population dynamics. We used basic structural model (BSM), a state-space time series model, to decompose and de-trend 25 years of monthly live-trapping data for Microtus ochrogaster, M. pennsylvanicus, and

Guiming Wang; Lowell L. Getz

2007-01-01

418

Prey selection, food habits and dietary overlap between leopard Panthera pardus (Mammalia: Carnivora) and re-introduced tiger Panthera tigris (Mammalia: Carnivora) in a semi-arid forest of Sariska Tiger Reserve, Western India  

Microsoft Academic Search

After the extermination of tigers in Sariska Tiger Reserve, Western India in 2004, three tigers were re-introduced in Sariska during 2008–2009. The present study examined the prey selection and dietary overlap between leopard and tiger after re-introduction of tiger in the study area. Scat analysis revealed the presence of nine prey species in leopard scat (n?=?90 scats) and five prey

K. Mondal; S. Gupta; S. Bhattacharjee; Q. Qureshi; K. Sankar

2012-01-01

419

Comparison of climate space and phylogeny of Marmota (Mammalia: Rodentia) indicates a connection between evolutionary history and climate preference  

Microsoft Academic Search

Palaeobiologists have investigated the evolutionary responses of extinct organisms to climate change, and have also used extinct organisms to reconstruct palaeoclimates. There is evidence of a disconnection between climate change and evolution that suggests that organisms may not be accurate palaeoclimate indicators. Here, marmots (Marmota sp.) are used as a case study to examine whether similarity of climate preferences is

Edward Byrd Davis

2005-01-01

420

Comparison of climate space and phylogeny of Marmota (Mammalia: Rodentia) indicates a connection between evolutionary history and climate preference  

PubMed Central

Palaeobiologists have investigated the evolutionary responses of extinct organisms to climate change, and have also used extinct organisms to reconstruct palaeoclimates. There is evidence of a disconnection between climate change and evolution that suggests that organisms may not be accurate palaeoclimate indicators. Here, marmots (Marmota sp.) are used as a case study to examine whether similarity of climate preferences is correlated with evolutionary relatedness of species. This study tests for a relationship between phylogenetic distance and `climate distance' of species within a clade. There should be a significant congruence between maximum likelihood distance and standardized Euclidian distance between climates if daughter species tend to stay in environments similar to parent species. Marmots make a good test case because there are many extant species, their phylogenies are well established and individual survival is linked to climatic factors. A Mantel test indicates a significant correlation between climate and phylogenetic distance matrices, but this relationship explains only a small fraction of the variance (regression R2=0.114). These results suggest that (i) closely related species of marmots tend to stay in similar environments; (ii) marmots may be more susceptible than many mammals to global climate change; and (iii) because of the considerable noise in this system, the correlation cannot be used for detailed palaeoclimate reconstruction. PMID:15799948

Davis, Edward Byrd

2005-01-01

421

Cytogenetic evidence for the specific distinction of an Alaskan marmot, Marmota broweri Hall and Gilmore (Mammalia: Sciuridae)  

Microsoft Academic Search

Cytogenetic studies based upon somatic cells (bone marrow) have disclosed that the marmot hitherto designated Marmota caligata broweriHall and Gilmore, occurring in the Brooks Range of arctic Alaska, differs from M. c. caligata (Eschscholtz) in number of chromosomes (2n=36 as compared with 2n=42 in M. caligata) and in proportions of chromosomal types. Typical karyograms for the two species are presented.

Robert L. Rausch; Virginia R. Rausch

1965-01-01

422

Postglacial colonization of northwestern North America by the forest-associated American marten ( Martes americana , Mammalia: Carnivora: Mustelidae)  

Microsoft Academic Search

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

KAREN D. S TONE; R ODNEY W. F LYNN; JOSEPH A. C OOK

423

Molecules, morphometrics and new fossils provide an integrated view of the evolutionary history of Rhinopomatidae (Mammalia: Chiroptera)  

Microsoft Academic Search

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

Pavel Hulva; Ivan Horá?ek; Petr Benda

2007-01-01

424

The Adaptive Significance of Enamel Loss in the Mandibular Incisors of Cercopithecine Primates (Mammalia: Cercopithecidae): A Finite Element Modelling Study  

PubMed Central

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

Kupczik, Kornelius; Lev-Tov Chattah, Netta

2014-01-01

425

Chewing through the Miocene: an examination of the feeding musculature in the ground sloth Hapalops from South America (Mammalia: Pilosa)  

PubMed Central

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

Naples, Virginia L.; McAfee, Robert K.

2014-01-01

426

Sensitivity of populations of bats (Mammalia: Chiroptera) in relation to human development in northern Paraná, southern Brazil.  

PubMed

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 Paraná 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

Reis, N R; Gallo, P H; Peracchi, A L; Lima, L P; Fregonezi, M N

2012-08-01

427

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)

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 Süßenborn, 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.

Kahlke, Ralf-Dietrich; Kaiser, Thomas M.

2011-08-01