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Sample records for mammals increased taxon

  1. Maintenance of trophic structure in fossil mammal communities: site occupancy and taxon resilience.

    PubMed

    Jernvall, Jukka; Fortelius, Mikael

    2004-11-01

    Commonness of organisms typically fluctuates through time, and understanding such fluctuations has long been an important part of ecological research. Studies at paleontological timescales provide a perspective on how changes in population size might affect community structure over millions of years. To overcome the obstacle that population size parameters such as abundance are difficult to detect in the fossil record, we here used fossil locality coverage to approximate changes in site occupancy in the Neogene of Europe over the course of 20 million years. Our aim was to examine whether the trophic structure of mammalian communities is maintained through time despite continuing environmental change. Ecomorphological grouping of fossils indicates that herbivore genera have low taxon resilience in that each genus has predominantly only one locality coverage peak before disappearance. Despite this continuous replacement of the most prevalent herbivore genera, the herbivore trophic group as a whole remains the largest and maintains a roughly constant share of locality coverage throughout the Neogene. The successive herbivore genera, however, show increasing adaptations to harshening environments, indicating shifting properties of niches while the overall trophic structure is conserved. Carnivores, dependent on primary productivity for food indirectly through their prey, show moderate lack of resilience. In contrast, in omnivores changes in locality coverage are close to random fluctuations.

  2. Framing the Salmonidae Family Phylogenetic Portrait: A More Complete Picture from Increased Taxon Sampling

    PubMed Central

    Crête-Lafrenière, Alexis; Weir, Laura K.; Bernatchez, Louis

    2012-01-01

    Considerable research efforts have focused on elucidating the systematic relationships among salmonid fishes; an understanding of these patterns of relatedness will inform conservation- and fisheries-related issues, as well as provide a framework for investigating evolutionary mechanisms in the group. However, uncertainties persist in current Salmonidae phylogenies due to biological and methodological factors, and a comprehensive phylogeny including most representatives of the family could provide insight into the causes of these difficulties. Here we increase taxon sampling by including nearly all described salmonid species (n = 63) to present a time-calibrated and more complete portrait of Salmonidae using a combination of molecular markers and analytical techniques. This strategy improved resolution by increasing the signal-to-noise ratio and helped discriminate methodological and systematic errors from sources of difficulty associated with biological processes. Our results highlight novel aspects of salmonid evolution. First, we call into question the widely-accepted evolutionary relationships among sub-families and suggest that Thymallinae, rather than Coregoninae, is the sister group to the remainder of Salmonidae. Second, we find that some groups in Salmonidae are older than previously thought and that the mitochondrial rate of molecular divergence varies markedly among genes and clades. We estimate the age of the family to be 59.1 MY (CI: 63.2-58.1 MY) old, which likely corresponds to the timing of whole genome duplication in salmonids. The average, albeit highly variable, mitochondrial rate of molecular divergence was estimated as ∼0.31%/MY (CI: 0.27–0.36%/MY). Finally, we suggest that some species require taxonomic revision, including two monotypic genera, Stenodus and Salvethymus. In addition, we resolve some relationships that have been notoriously difficult to discern and present a clearer picture of the evolution of the group. Our findings

  3. Intensive removal of signal crayfish (Pacifastacus leniusculus) from rivers increases numbers and taxon richness of macroinvertebrate species

    PubMed Central

    Moorhouse, Tom P; Poole, Alison E; Evans, Laura C; Bradley, David C; Macdonald, David W

    2014-01-01

    Invasive species are a major cause of species extinction in freshwater ecosystems, and crayfish species are particularly pervasive. The invasive American signal crayfish Pacifastacus leniusculus has impacts over a range of trophic levels, but particularly on benthic aquatic macroinvertebrates. Our study examined the effect on the macroinvertebrate community of removal trapping of signal crayfish from UK rivers. Crayfish were intensively trapped and removed from two tributaries of the River Thames to test the hypothesis that lowering signal crayfish densities would result in increases in macroinvertebrate numbers and taxon richness. We removed 6181 crayfish over four sessions, resulting in crayfish densities that decreased toward the center of the removal sections. Conversely in control sections (where crayfish were trapped and returned), crayfish density increased toward the center of the section. Macroinvertebrate numbers and taxon richness were inversely correlated with crayfish densities. Multivariate analysis of the abundance of each taxon yielded similar results and indicated that crayfish removals had positive impacts on macroinvertebrate numbers and taxon richness but did not alter the composition of the wider macroinvertebrate community. Synthesis and applications: Our results demonstrate that non-eradication-oriented crayfish removal programmes may lead to increases in the total number of macroinvertebrates living in the benthos. This represents the first evidence that removing signal crayfish from riparian systems, at intensities feasible during control attempts or commercial crayfishing, may be beneficial for a range of sympatric aquatic macroinvertebrates. PMID:24634733

  4. Increased homeothermy during reproduction in a basal placental mammal.

    PubMed

    Levesque, Danielle L; Lovegrove, Barry G

    2014-05-01

    Homeothermic endothermy, the maintenance of a high and stable body temperature (Tb) using heat produced by elevated metabolism, is energetically expensive. There is increasing evidence that the earliest endotherms were heterotherms that, rather than maintaining strict homeothermy, allowed Tb to fluctuate with large variations between active and rest-phase Tb. The high level of homeothermy observed in modern mammals is therefore likely to have evolved from an ancestral heterothermic state. One of the hypotheses for the evolution of endothermy is that homeothermy allows for greater energetic output during reproduction (parental care model). We tested this hypothesis by measuring metabolic rates over a range of ambient temperatures in both reproductive and non-reproductive greater hedgehog tenrecs (Setifer setosus), a physiologically primitive mammal from Madagascar. Tenrecs have some of the lowest metabolic rates and highest levels of Tb variability of any mammal and are therefore good models of the ancestral eutherian state. During pregnancy and lactation, there was an increase in metabolism and Tb below the thermoneutral zone, accompanied by a decrease in Tb variability. The lower critical limit of the thermoneutral zone was estimated at ~25°C. However, whereas increases in resting metabolism were substantial below 20°C (up to 150% higher during reproduction), daytime rest-phase ambient temperatures at the study site rarely reached equivalent low levels. Thus, S. setosus provide an example for how relatively low-cost increases in homeothermy could have led to substantial increases in fitness by allowing for the faster production of young. The mechanisms necessary for increases in thermogenesis during reproduction would have further benefited the development of homeothermy in mammals.

  5. Larger brain size indirectly increases vulnerability to extinction in mammals.

    PubMed

    Gonzalez-Voyer, Alejandro; González-Suárez, Manuela; Vilà, Carles; Revilla, Eloy

    2016-06-01

    Although previous studies have addressed the question of why large brains evolved, we have limited understanding of potential beneficial or detrimental effects of enlarged brain size in the face of current threats. Using novel phylogenetic path analysis, we evaluated how brain size directly and indirectly, via its effects on life history and ecology, influences vulnerability to extinction across 474 mammalian species. We found that larger brains, controlling for body size, indirectly increase vulnerability to extinction by extending the gestation period, increasing weaning age, and limiting litter sizes. However, we found no evidence of direct, beneficial, or detrimental effects of brain size on vulnerability to extinction, even when we explicitly considered the different types of threats that lead to vulnerability. Order-specific analyses revealed qualitatively similar patterns for Carnivora and Artiodactyla. Interestingly, for Primates, we found that larger brain size was directly (and indirectly) associated with increased vulnerability to extinction. Our results indicate that under current conditions, the constraints on life history imposed by large brains outweigh the potential benefits, undermining the resilience of the studied mammals. Contrary to the selective forces that have favored increased brain size throughout evolutionary history, at present, larger brains have become a burden for mammals. PMID:27159368

  6. Larger brain size indirectly increases vulnerability to extinction in mammals.

    PubMed

    Gonzalez-Voyer, Alejandro; González-Suárez, Manuela; Vilà, Carles; Revilla, Eloy

    2016-06-01

    Although previous studies have addressed the question of why large brains evolved, we have limited understanding of potential beneficial or detrimental effects of enlarged brain size in the face of current threats. Using novel phylogenetic path analysis, we evaluated how brain size directly and indirectly, via its effects on life history and ecology, influences vulnerability to extinction across 474 mammalian species. We found that larger brains, controlling for body size, indirectly increase vulnerability to extinction by extending the gestation period, increasing weaning age, and limiting litter sizes. However, we found no evidence of direct, beneficial, or detrimental effects of brain size on vulnerability to extinction, even when we explicitly considered the different types of threats that lead to vulnerability. Order-specific analyses revealed qualitatively similar patterns for Carnivora and Artiodactyla. Interestingly, for Primates, we found that larger brain size was directly (and indirectly) associated with increased vulnerability to extinction. Our results indicate that under current conditions, the constraints on life history imposed by large brains outweigh the potential benefits, undermining the resilience of the studied mammals. Contrary to the selective forces that have favored increased brain size throughout evolutionary history, at present, larger brains have become a burden for mammals.

  7. Cross-taxon congruence and environmental conditions

    PubMed Central

    2010-01-01

    Background Diversity patterns of different taxa typically covary in space, a phenomenon called cross-taxon congruence. This pattern has been explained by the effect of one taxon diversity on taxon diversity, shared biogeographic histories of different taxa, and/or common responses to environmental conditions. A meta-analysis of the association between environment and diversity patterns found that in 83 out of 85 studies, more than 60% of the spatial variability in species richness was related to variables representing energy, water or their interaction. The role of the environment determining taxa diversity patterns leads us to hypothesize that this would explain the observed cross-taxon congruence. However, recent analyses reported the persistence of cross-taxon congruence when environmental effect was statistically removed. Here we evaluate this hypothesis, analyzing the cross-taxon congruence between birds and mammals in the Brazilian Cerrado, and assess the environmental role on the spatial covariation in diversity patterns. Results We found a positive association between avian and mammal richness and a positive latitudinal trend for both groups in the Brazilian Cerrado. Regression analyses indicated an effect of latitude, PET, and mean temperature over both biological groups. In addition, we show that NDVI was only associated with avian diversity; while the annual relative humidity, was only correlated with mammal diversity. We determined the environmental effects on diversity in a path analysis that accounted for 73% and 76% of the spatial variation in avian and mammal richness. However, an association between avian and mammal diversity remains significant. Indeed, the importance of this link between bird and mammal diversity was also supported by a significant association between birds and mammal spatial autoregressive model residuals. Conclusion Our study corroborates the main role of environmental conditions on diversity patterns, but suggests that other

  8. Non-monophyly of most supraspecific taxa of calcareous sponges (Porifera, Calcarea) revealed by increased taxon sampling and partitioned Bayesian analysis of ribosomal DNA.

    PubMed

    Dohrmann, Martin; Voigt, Oliver; Erpenbeck, Dirk; Wörheide, Gert

    2006-09-01

    Calcareous sponges (Porifera, Calcarea) play an important role for our understanding of early metazoan evolution, since several molecular studies suggested their closer relationship to Eumetazoa than to the other two sponge 'classes,' Demospongiae and Hexactinellida. The division of Calcarea into the subtaxa Calcinea and Calcaronea is well established by now, but their internal relationships remain largely unresolved. Here, we estimate phylogenetic relationships within Calcarea in a Bayesian framework, using full-length 18S and partial 28S ribosomal DNA sequences. Both genes were analyzed separately and in combination and were further partitioned by stem and loop regions, the former being modelled to take non-independence of paired sites into account. By substantially increasing taxon sampling, we show that most of the traditionally recognized supraspecific taxa within Calcinea and Calcaronea are not monophyletic, challenging the existing classification system, while monophyly of Calcinea and Calcaronea is again highly supported.

  9. Increase in antimicrobial resistance in bacteria isolated from stranded marine mammals of the Northwest Atlantic.

    PubMed

    Wallace, Courtney C; Yund, Philip O; Ford, Timothy E; Matassa, Keith A; Bass, Anna L

    2013-06-01

    Studies on marine mammals can inform our understanding of the environmental health of the ocean. To evaluate the potential for changes in antimicrobial resistance, we analyzed a database spanning 2004-2010 that consisted of bacterial isolate identity and antimicrobial sensitivity for stranded pinnipeds in the Northwest Atlantic. Samples (n = 170) from treated animals yielded 310 bacterial isolates representing 24 taxa. We evaluated changes in antimicrobial class resistance from 2004 to 2010 for eight taxa. Escherichia coli displayed a significant increase in resistance to several antimicrobial classes. Other taxa displayed significant increases in resistance to aminoglycosides, and/or fluoroquinolones. In addition, we observed a significant increase in multiple antimicrobial resistance in cultures from untreated animals. These results demonstrate an increase in resistance among common bacterial pathogens of marine mammals over a time span of 6 years. PMID:23636484

  10. Examination of the pathological dissociation taxon in depersonalization disorder.

    PubMed

    Simeon, Daphne; Knutelska, Margaret; Nelson, Dorothy; Guralnik, Orna; Schmeidler, James

    2003-11-01

    In recent years, the pathologic dissociation taxon developed by Waller, Putnam, and Carlson (Psychological Methods 1:300-321, 1996) from a Dissociative Identity Disorder (DID) sample has been increasingly used in studies of dissociation in general. However, the taxon's convergence with dissociative diagnoses other than DID, as well as the taxon's central premise that pathologic dissociation is a categorical rather than a dimensional construct, remain areas of exploration. This report examines the applicability of the pathologic dissociation taxon to Depersonalization Disorder (DPD). The Dissociative Experiences Scale was administered to 100 consecutively recruited DPD subjects diagnosed by semistructured clinical interview and by the SCID-D. Taxon membership probability was calculated using the recommended SAS scoring program. Approximately 2/3 of subjects (N = 64) had a very high probability (>.80) of belonging to the taxon, while 1/3 of subjects had a very low probability (<.10) of belonging to the taxon. A taxon cutoff score of 13 yielded an 81% sensitivity in detecting the presence of DPD. The modest convergence between taxonic membership and clinical dissociative disorder diagnosis suggests that the taxon may have important limitations in its use, at least when applied to DPD in its current form. As previously, we continue to recommend a low taxon cutoff score (13) for the sensitive detection of depersonalization disorder. The inference that pathologic dissociation is a unitary and categorical entity is also discussed.

  11. Hibernation is associated with increased survival and the evolution of slow life histories among mammals.

    PubMed

    Turbill, Christopher; Bieber, Claudia; Ruf, Thomas

    2011-11-22

    Survival probability is predicted to underlie the evolution of life histories along a slow-fast continuum. Hibernation allows a diverse range of small mammals to exhibit seasonal dormancy, which might increase survival and consequently be associated with relatively slow life histories. We used phylogenetically informed GLS models to test for an effect of hibernation on seasonal and annual survival, and on key attributes of life histories among mammals. Monthly survival was in most cases higher during hibernation compared with the active season, probably because inactivity minimizes predation. Hibernators also have approximately 15 per cent higher annual survival than similar sized non-hibernating species. As predicted, we found an effect of hibernation on the relationships between life history attributes and body mass: small hibernating mammals generally have longer maximum life spans (50% greater for a 50 g species), reproduce at slower rates, mature at older ages and have longer generation times compared with similar-sized non-hibernators. In accordance with evolutionary theories, however, hibernating species do not have longer life spans than non-hibernators with similar survival rates, nor do they have lower reproductive rates than non-hibernators with similar maximum life spans. Thus, our combined results suggest that (i) hibernation is associated with high rates of overwinter and annual survival, and (ii) an increase in survival in hibernating species is linked with the coevolution of traits indicative of relatively slow life histories.

  12. Modeling effectiveness of gradual increases in source level to mitigate effects of sonar on marine mammals.

    PubMed

    Von Benda-Beckmann, Alexander M; Wensveen, Paul J; Kvadsheim, Petter H; Lam, Frans-Peter A; Miller, Patrick J O; Tyack, Peter L; Ainslie, Michael A

    2014-02-01

    Ramp-up or soft-start procedures (i.e., gradual increase in the source level) are used to mitigate the effect of sonar sound on marine mammals, although no one to date has tested whether ramp-up procedures are effective at reducing the effect of sound on marine mammals. We investigated the effectiveness of ramp-up procedures in reducing the area within which changes in hearing thresholds can occur. We modeled the level of sound killer whales (Orcinus orca) were exposed to from a generic sonar operation preceded by different ramp-up schemes. In our model, ramp-up procedures reduced the risk of killer whales receiving sounds of sufficient intensity to affect their hearing. The effectiveness of the ramp-up procedure depended strongly on the assumed response threshold and differed with ramp-up duration, although extending the duration of the ramp up beyond 5 min did not add much to its predicted mitigating effect. The main factors that limited effectiveness of ramp up in a typical antisubmarine warfare scenario were high source level, rapid moving sonar source, and long silences between consecutive sonar transmissions. Our exposure modeling approach can be used to evaluate and optimize mitigation procedures. PMID:24471782

  13. Actuarial senescence can increase the risk of extinction of mammal populations.

    PubMed

    Robert, Alexandre; Chantepie, Stéphane; Pavard, Samuel; Sarrazin, François; Teplitsky, Céline

    2015-01-01

    Despite recent acknowledgement that senescence can have negative impact on survival and fertility in natural environments across a wide range of animal species, we still do not know if it can reduce the viability of wild endangered populations. Focusing on actuarial senescence (i.e., the decline of survival probabilities at old ages), we use species-specific demographic information to project the extinction risk of wild populations of 58 species of mammals, accounting (or not) for senescence. Our projections reveal potential negative effects of aging on population viability, with an average decrease of 27% of the time to extinction and a potential deterioration of the population-level projected conservation status in 10% of the species. Senescence is associated with particularly strong increases of the extinction risk in species with low mortality rates and long intervals between litters, independently of their place in the phylogeny, indicating that the pace of life history can be used to forecast the detrimental effects of aging on the viability of species. The aim of the various existing systems of classification of threatened species is to set conservation priorities based on assessments of extinction risk. Our results indicate that the quantitative effects of senescence on extinction are highly heterogeneous, which can affect the ranking of species and populations when setting conservation, priorities. In mammals, based on life history traits of a few species, generic patterns of senescence can be incorporated into projection population models to minimize these biases in viability assessments.

  14. Strong Artificial Selection in Domestic Mammals Did Not Result in an Increased Recombination Rate

    PubMed Central

    Muñoz-Fuentes, Violeta; Marcet-Ortega, Marina; Alkorta-Aranburu, Gorka; Linde Forsberg, Catharina; Morrell, Jane M.; Manzano-Piedras, Esperanza; Söderberg, Arne; Daniel, Katrin; Villalba, Adrian; Toth, Attila; Di Rienzo, Anna; Roig, Ignasi; Vilà, Carles

    2015-01-01

    Recombination rates vary in intensity and location at the species, individual, sex and chromosome levels. Despite the fundamental biological importance of this process, the selective forces that operate to shape recombination rate and patterns are unclear. Domestication offers a unique opportunity to study the interplay between recombination and selection. In domesticates, intense selection for particular traits is imposed on small populations over many generations, resulting in organisms that differ, sometimes dramatically, in morphology and physiology from their wild ancestor. Although earlier studies suggested increased recombination rate in domesticates, a formal comparison of recombination rates between domestic mammals and their wild congeners was missing. In order to determine broad-scale recombination rate, we used immunolabeling detection of MLH1 foci as crossover markers in spermatocytes in three pairs of closely related wild and domestic species (dog and wolf, goat and ibex, and sheep and mouflon). In the three pairs, and contrary to previous suggestions, our data show that contemporary recombination rate is higher in the wild species. Subsequently, we inferred recombination breakpoints in sequence data for 16 genomic regions in dogs and wolves, each containing a locus associated with a dog phenotype potentially under selection during domestication. No difference in the number and distribution of recombination breakpoints was found between dogs and wolves. We conclude that our data indicate that strong directional selection did not result in changes in recombination in domestic mammals, and that both upper and lower bounds for crossover rates may be tightly regulated. PMID:25414125

  15. Strong artificial selection in domestic mammals did not result in an increased recombination rate.

    PubMed

    Muñoz-Fuentes, Violeta; Marcet-Ortega, Marina; Alkorta-Aranburu, Gorka; Linde Forsberg, Catharina; Morrell, Jane M; Manzano-Piedras, Esperanza; Söderberg, Arne; Daniel, Katrin; Villalba, Adrian; Toth, Attila; Di Rienzo, Anna; Roig, Ignasi; Vilà, Carles

    2015-02-01

    Recombination rates vary in intensity and location at the species, individual, sex and chromosome levels. Despite the fundamental biological importance of this process, the selective forces that operate to shape recombination rate and patterns are unclear. Domestication offers a unique opportunity to study the interplay between recombination and selection. In domesticates, intense selection for particular traits is imposed on small populations over many generations, resulting in organisms that differ, sometimes dramatically, in morphology and physiology from their wild ancestor. Although earlier studies suggested increased recombination rate in domesticates, a formal comparison of recombination rates between domestic mammals and their wild congeners was missing. In order to determine broad-scale recombination rate, we used immunolabeling detection of MLH1 foci as crossover markers in spermatocytes in three pairs of closely related wild and domestic species (dog and wolf, goat and ibex, and sheep and mouflon). In the three pairs, and contrary to previous suggestions, our data show that contemporary recombination rate is higher in the wild species. Subsequently, we inferred recombination breakpoints in sequence data for 16 genomic regions in dogs and wolves, each containing a locus associated with a dog phenotype potentially under selection during domestication. No difference in the number and distribution of recombination breakpoints was found between dogs and wolves. We conclude that our data indicate that strong directional selection did not result in changes in recombination in domestic mammals, and that both upper and lower bounds for crossover rates may be tightly regulated. PMID:25414125

  16. Modeling effectiveness of gradual increases in source level to mitigate effects of sonar on marine mammals.

    PubMed

    Von Benda-Beckmann, Alexander M; Wensveen, Paul J; Kvadsheim, Petter H; Lam, Frans-Peter A; Miller, Patrick J O; Tyack, Peter L; Ainslie, Michael A

    2014-02-01

    Ramp-up or soft-start procedures (i.e., gradual increase in the source level) are used to mitigate the effect of sonar sound on marine mammals, although no one to date has tested whether ramp-up procedures are effective at reducing the effect of sound on marine mammals. We investigated the effectiveness of ramp-up procedures in reducing the area within which changes in hearing thresholds can occur. We modeled the level of sound killer whales (Orcinus orca) were exposed to from a generic sonar operation preceded by different ramp-up schemes. In our model, ramp-up procedures reduced the risk of killer whales receiving sounds of sufficient intensity to affect their hearing. The effectiveness of the ramp-up procedure depended strongly on the assumed response threshold and differed with ramp-up duration, although extending the duration of the ramp up beyond 5 min did not add much to its predicted mitigating effect. The main factors that limited effectiveness of ramp up in a typical antisubmarine warfare scenario were high source level, rapid moving sonar source, and long silences between consecutive sonar transmissions. Our exposure modeling approach can be used to evaluate and optimize mitigation procedures.

  17. Competition asymmetry with taxon divergence.

    PubMed

    Barnes, David K A

    2003-03-22

    Most organisms experience competition for resources, probably most of the time. As the structure and requirements of closely related species are generally liable to be more similar than in distantly linked species, Darwin suggested that the potential for competition was greater in the former. Since that time, studies have concentrated on interactions of either conspecifics or congeneric species. Shared critical resources, which organisms compete for, are generally mates, food and space (for access to the former). Whilst mates are valued only within species, in that the definition of a species requires it so, both food and space have the potential to be shared by very different organisms. It is now clear that vertebrates may compete with remotely related species: e.g. with squid for krill and with insects for nectar or seeds. Diamond suggested that (i) mutual aggression, (ii) displacement and (iii) evolutionary change in morphology would be increasingly asymmetric with competitor dissimilarity. Thus, with increasing taxonomic distance between two competitors (A and B), increasing aggression is exhibited between them and, increasingly, one consistently displaces the other. Here, Darwin's suggestion and Diamond's first two theories are tested across a taxonomic spectrum for the first time to the best of the author's knowledge. The proportion of spatial competitors in two different marine invertebrate groups demonstrating mutual aggression and displacement increases with taxon divergence (Nei's genetic identity). Congenerics were twice as likely to fight as conspecifics, and confamilial competitors were three times as likely to fight as conspecifics. This relationship seems robust to taxonomic and environmental variability. Competitors do not need to be as distant as birds and bees for complete asymmetry, a different family seems sufficient.

  18. Contrasting coloration in terrestrial mammals

    PubMed Central

    Caro, Tim

    2008-01-01

    Here I survey, collate and synthesize contrasting coloration in 5000 species of terrestrial mammals focusing on black and white pelage. After briefly reviewing alternative functional hypotheses for coloration in mammals, I examine nine colour patterns and combinations on different areas of the body and for each mammalian taxon to try to identify the most likely evolutionary drivers of contrasting coloration. Aposematism and perhaps conspecific signalling are the most consistent explanations for black and white pelage in mammals; background matching may explain white pelage. Evidence for contrasting coloration is being involved in crypsis through pattern blending, disruptive coloration or serving other functions, such as signalling dominance, lures, reducing eye glare or in temperature regulation has barely moved beyond anecdotal stages of investigation. Sexual dichromatism is limited in this taxon and its basis is unclear. Astonishingly, the functional significance of pelage coloration in most large charismatic black and white mammals that were new to science 150 years ago still remains a mystery. PMID:18990666

  19. Does moonlight increase predation risk? Meta-analysis reveals divergent responses of nocturnal mammals to lunar cycles.

    PubMed

    Prugh, Laura R; Golden, Christopher D

    2014-03-01

    The risk of predation strongly affects mammalian population dynamics and community interactions. Bright moonlight is widely believed to increase predation risk for nocturnal mammals by increasing the ability of predators to detect prey, but the potential for moonlight to increase detection of predators and the foraging efficiency of prey has largely been ignored. Studies have reported highly variable responses to moonlight among species, calling into question the assumption that moonlight increases risk. Here, we conducted a quantitative meta-analysis examining the effects of moonlight on the activity of 59 nocturnal mammal species to test the assumption that moonlight increases predation risk. We examined patterns of lunarphilia and lunarphobia across species in relation to factors such as trophic level, habitat cover preference and visual acuity. Across all species included in the meta-analysis, moonlight suppressed activity. The magnitude of suppression was similar to the presence of a predator in experimental studies of foraging rodents (13.6% and 18.7% suppression, respectively). Contrary to the expectation that moonlight increases predation risk for all prey species, however, moonlight effects were not clearly related to trophic level and were better explained by phylogenetic relatedness, visual acuity and habitat cover. Moonlight increased the activity of prey species that use vision as their primary sensory system and suppressed the activity of species that primarily use other senses (e.g. olfaction, echolocation), and suppression was strongest in open habitat types. Strong taxonomic patterns underlay these relationships: moonlight tended to increase primate activity, whereas it tended to suppress the activity of rodents, lagomorphs, bats and carnivores. These results indicate that visual acuity and habitat cover jointly moderate the effect of moonlight on predation risk, whereas trophic position has little effect. While the net effect of moonlight appears

  20. A century of change in Kenya's mammal communities: increased richness and decreased uniqueness in six protected areas.

    PubMed

    Tóth, Anikó B; Lyons, S Kathleen; Behrensmeyer, Anna K

    2014-01-01

    The potential for large-scale biodiversity losses as a result of climate change and human impact presents major challenges for ecology and conservation science. Governments around the world have established national parks and wildlife reserves to help protect biodiversity, but there are few studies on the long-term consequences of this strategy. We use Kenya as a case study to investigate species richness and other attributes of mammal communities in 6 protected areas over the past century. Museum records from African expeditions that comprehensively sampled mammals from these same areas in the early 1900's provide a baseline for evaluating changes in species richness and community structure over time. We compare species lists assembled from archived specimens (1896-1950) to those of corresponding modern protected areas (1950-2013). Species richness in Kenya was stable or increased at 5 out of 6 sites from historical to modern times. Beta-diversity, in contrast, decreased across all sites. Potential biases such as variable historical vs. modern collection effort and detection of small-bodied, rare, and low-visibility species do not account for the observed results. We attribute the pattern of decreased beta diversity primarily to increased site occupancy by common species across all body size classes. Despite a decrease in land area available to wildlife, our data do not show the extinctions predicted by species-area relationships. Moreover, the results indicate that species-area curves based solely on protected areas could underestimate diversity because they do not account for mammal species whose ranges extend beyond protected area boundaries. We conclude that the 6 protected areas have been effective in preserving species richness in spite of continuing conversion of wild grasslands to cropland, but the overall decrease in beta diversity indicates a decline in the uniqueness of mammal communities that historically characterized Kenya's varied landscape.

  1. A century of change in Kenya's mammal communities: increased richness and decreased uniqueness in six protected areas.

    PubMed

    Tóth, Anikó B; Lyons, S Kathleen; Behrensmeyer, Anna K

    2014-01-01

    The potential for large-scale biodiversity losses as a result of climate change and human impact presents major challenges for ecology and conservation science. Governments around the world have established national parks and wildlife reserves to help protect biodiversity, but there are few studies on the long-term consequences of this strategy. We use Kenya as a case study to investigate species richness and other attributes of mammal communities in 6 protected areas over the past century. Museum records from African expeditions that comprehensively sampled mammals from these same areas in the early 1900's provide a baseline for evaluating changes in species richness and community structure over time. We compare species lists assembled from archived specimens (1896-1950) to those of corresponding modern protected areas (1950-2013). Species richness in Kenya was stable or increased at 5 out of 6 sites from historical to modern times. Beta-diversity, in contrast, decreased across all sites. Potential biases such as variable historical vs. modern collection effort and detection of small-bodied, rare, and low-visibility species do not account for the observed results. We attribute the pattern of decreased beta diversity primarily to increased site occupancy by common species across all body size classes. Despite a decrease in land area available to wildlife, our data do not show the extinctions predicted by species-area relationships. Moreover, the results indicate that species-area curves based solely on protected areas could underestimate diversity because they do not account for mammal species whose ranges extend beyond protected area boundaries. We conclude that the 6 protected areas have been effective in preserving species richness in spite of continuing conversion of wild grasslands to cropland, but the overall decrease in beta diversity indicates a decline in the uniqueness of mammal communities that historically characterized Kenya's varied landscape. PMID

  2. A Century of Change in Kenya's Mammal Communities: Increased Richness and Decreased Uniqueness in Six Protected Areas

    PubMed Central

    Tóth, Anikó B.; Lyons, S. Kathleen; Behrensmeyer, Anna K.

    2014-01-01

    The potential for large-scale biodiversity losses as a result of climate change and human impact presents major challenges for ecology and conservation science. Governments around the world have established national parks and wildlife reserves to help protect biodiversity, but there are few studies on the long-term consequences of this strategy. We use Kenya as a case study to investigate species richness and other attributes of mammal communities in 6 protected areas over the past century. Museum records from African expeditions that comprehensively sampled mammals from these same areas in the early 1900's provide a baseline for evaluating changes in species richness and community structure over time. We compare species lists assembled from archived specimens (1896–1950) to those of corresponding modern protected areas (1950–2013). Species richness in Kenya was stable or increased at 5 out of 6 sites from historical to modern times. Beta-diversity, in contrast, decreased across all sites. Potential biases such as variable historical vs. modern collection effort and detection of small-bodied, rare, and low-visibility species do not account for the observed results. We attribute the pattern of decreased beta diversity primarily to increased site occupancy by common species across all body size classes. Despite a decrease in land area available to wildlife, our data do not show the extinctions predicted by species-area relationships. Moreover, the results indicate that species-area curves based solely on protected areas could underestimate diversity because they do not account for mammal species whose ranges extend beyond protected area boundaries. We conclude that the 6 protected areas have been effective in preserving species richness in spite of continuing conversion of wild grasslands to cropland, but the overall decrease in beta diversity indicates a decline in the uniqueness of mammal communities that historically characterized Kenya's varied landscape

  3. Testing for Depéret's Rule (Body Size Increase) in Mammals using Combined Extinct and Extant Data

    PubMed Central

    Bokma, Folmer; Godinot, Marc; Maridet, Olivier; Ladevèze, Sandrine; Costeur, Loïc; Solé, Floréal; Gheerbrant, Emmanuel; Peigné, Stéphane; Jacques, Florian; Laurin, Michel

    2016-01-01

    Whether or not evolutionary lineages in general show a tendency to increase in body size has often been discussed. This tendency has been dubbed “Cope's rule” but because Cope never hypothesized it, we suggest renaming it after Depéret, who formulated it clearly in 1907. Depéret's rule has traditionally been studied using fossil data, but more recently a number of studies have used present-day species. While several paleontological studies of Cenozoic placental mammals have found support for increasing body size, most studies of extant placentals have failed to detect such a trend. Here, we present a method to combine information from present-day species with fossil data in a Bayesian phylogenetic framework. We apply the method to body mass estimates of a large number of extant and extinct mammal species, and find strong support for Depéret's rule. The tendency for size increase appears to be driven not by evolution toward larger size in established species, but by processes related to the emergence of new species. Our analysis shows that complementary data from extant and extinct species can greatly improve inference of macroevolutionary processes. PMID:26508768

  4. Testing for Depéret's Rule (Body Size Increase) in Mammals using Combined Extinct and Extant Data.

    PubMed

    Bokma, Folmer; Godinot, Marc; Maridet, Olivier; Ladevèze, Sandrine; Costeur, Loïc; Solé, Floréal; Gheerbrant, Emmanuel; Peigné, Stéphane; Jacques, Florian; Laurin, Michel

    2016-01-01

    Whether or not evolutionary lineages in general show a tendency to increase in body size has often been discussed. This tendency has been dubbed "Cope's rule" but because Cope never hypothesized it, we suggest renaming it after Depéret, who formulated it clearly in 1907. Depéret's rule has traditionally been studied using fossil data, but more recently a number of studies have used present-day species. While several paleontological studies of Cenozoic placental mammals have found support for increasing body size, most studies of extant placentals have failed to detect such a trend. Here, we present a method to combine information from present-day species with fossil data in a Bayesian phylogenetic framework. We apply the method to body mass estimates of a large number of extant and extinct mammal species, and find strong support for Depéret's rule. The tendency for size increase appears to be driven not by evolution toward larger size in established species, but by processes related to the emergence of new species. Our analysis shows that complementary data from extant and extinct species can greatly improve inference of macroevolutionary processes. PMID:26508768

  5. Can diving-induced tissue nitrogen supersaturation increase the chance of acoustically driven bubble growth in marine mammals?

    PubMed

    Houser, D S; Howard, R; Ridgway, S

    2001-11-21

    The potential for acoustically mediated causes of stranding in cetaceans (whales and dolphins) is of increasing concern given recent stranding events associated with anthropogenic acoustic activity. We examine a potentially debilitating non-auditory mechanism called rectified diffusion. Rectified diffusion causes gas bubble growth, which in an insonified animal may produce emboli, tissue separation and high, localized pressure in nervous tissue. Using the results of a dolphin dive study and a model of rectified diffusion for low-frequency exposure, we demonstrate that the diving behavior of cetaceans prior to an intense acoustic exposure may increase the chance of rectified diffusion. Specifically, deep diving and slow ascent/descent speed contributes to increased gas-tissue saturation, a condition that amplifies the likelihood of rectified diffusion. The depth of lung collapse limits nitrogen uptake per dive and the surface interval duration influences the amount of nitrogen washout from tissues between dives. Model results suggest that low-frequency rectified diffusion models need to be advanced, that the diving behavior of marine mammals of concern needs to be investigated to identify at-risk animals, and that more intensive studies of gas dynamics within diving marine mammals should be undertaken.

  6. Can diving-induced tissue nitrogen supersaturation increase the chance of acoustically driven bubble growth in marine mammals?

    PubMed

    Houser, D S; Howard, R; Ridgway, S

    2001-11-21

    The potential for acoustically mediated causes of stranding in cetaceans (whales and dolphins) is of increasing concern given recent stranding events associated with anthropogenic acoustic activity. We examine a potentially debilitating non-auditory mechanism called rectified diffusion. Rectified diffusion causes gas bubble growth, which in an insonified animal may produce emboli, tissue separation and high, localized pressure in nervous tissue. Using the results of a dolphin dive study and a model of rectified diffusion for low-frequency exposure, we demonstrate that the diving behavior of cetaceans prior to an intense acoustic exposure may increase the chance of rectified diffusion. Specifically, deep diving and slow ascent/descent speed contributes to increased gas-tissue saturation, a condition that amplifies the likelihood of rectified diffusion. The depth of lung collapse limits nitrogen uptake per dive and the surface interval duration influences the amount of nitrogen washout from tissues between dives. Model results suggest that low-frequency rectified diffusion models need to be advanced, that the diving behavior of marine mammals of concern needs to be investigated to identify at-risk animals, and that more intensive studies of gas dynamics within diving marine mammals should be undertaken. PMID:11894990

  7. Testing for Depéret's Rule (Body Size Increase) in Mammals using Combined Extinct and Extant Data.

    PubMed

    Bokma, Folmer; Godinot, Marc; Maridet, Olivier; Ladevèze, Sandrine; Costeur, Loïc; Solé, Floréal; Gheerbrant, Emmanuel; Peigné, Stéphane; Jacques, Florian; Laurin, Michel

    2016-01-01

    Whether or not evolutionary lineages in general show a tendency to increase in body size has often been discussed. This tendency has been dubbed "Cope's rule" but because Cope never hypothesized it, we suggest renaming it after Depéret, who formulated it clearly in 1907. Depéret's rule has traditionally been studied using fossil data, but more recently a number of studies have used present-day species. While several paleontological studies of Cenozoic placental mammals have found support for increasing body size, most studies of extant placentals have failed to detect such a trend. Here, we present a method to combine information from present-day species with fossil data in a Bayesian phylogenetic framework. We apply the method to body mass estimates of a large number of extant and extinct mammal species, and find strong support for Depéret's rule. The tendency for size increase appears to be driven not by evolution toward larger size in established species, but by processes related to the emergence of new species. Our analysis shows that complementary data from extant and extinct species can greatly improve inference of macroevolutionary processes.

  8. DNA Methylation is Associated with an Increased Level of Conservation at Nondegenerate Nucleotides in Mammals

    PubMed Central

    Chuang, Trees-Juen; Chen, Feng-Chi

    2014-01-01

    DNA methylation at CpG dinucleotides can significantly increase the rate of cytosine-to-thymine mutations and the level of sequence divergence. Although the correlations between DNA methylation and genomic sequence evolution have been widely studied, an unaddressed yet fundamental question is how DNA methylation is associated with the conservation of individual nucleotides in different sequence contexts. Here, we demonstrate that in mammalian exons, the correlations between DNA methylation and the conservation of individual nucleotides are dependent on the type of exonic sequence (coding or untranslated), the degeneracy of coding nucleotides, background selection pressure, and the relative position (first or nonfirst exon in the transcript) where the nucleotides are located. For untranslated and nonzero-fold degenerate nucleotides, methylated sites are less conserved than unmethylated sites regardless of background selection pressure and the relative position of the exon. For zero-fold degenerate (or nondegenerate) nucleotides, however, the reverse trend is observed in nonfirst coding exons and first coding exons that are under stringent background selection pressure. Furthermore, cytosine-to-thymine mutations at methylated zero-fold degenerate nucleotides are predicted to be more detrimental than those that occur at unmethylated nucleotides. As zero-fold and nonzero-fold degenerate nucleotides are very close to each other, our results suggest that the “functional resolution” of DNA methylation may be finer than previously recognized. In addition, the positive correlation between CpG methylation and the level of conservation at zero-fold degenerate nucleotides implies that CpG methylation may serve as an “indicator” of functional importance of these nucleotides. PMID:24157417

  9. Molecular phylogeny and divergence times of Malagasy tenrecs: Influence of data partitioning and taxon sampling on dating analyses

    PubMed Central

    2008-01-01

    Background Malagasy tenrecs belong to the Afrotherian clade of placental mammals and comprise three subfamilies divided in eight genera (Tenrecinae: Tenrec, Echinops, Setifer and Hemicentetes; Oryzorictinae: Oryzorictes, Limnogale and Microgale; Geogalinae:Geogale). The diversity of their morphology and incomplete taxon sampling made it difficult until now to resolve phylogenies based on either morphology or molecular data for this group. Therefore, in order to delineate the evolutionary history of this family, phylogenetic and dating analyses were performed on a four nuclear genes dataset (ADRA2B, AR, GHR and vWF) including all Malagasy tenrec genera. Moreover, the influence of both taxon sampling and data partitioning on the accuracy of the estimated ages were assessed. Results Within Afrotheria the vast majority of the nodes received a high support, including the grouping of hyrax with sea cow and the monophyly of both Afroinsectivora (Macroscelidea + Afrosoricida) and Afroinsectiphillia (Tubulidentata + Afroinsectivora). Strongly supported relationships were also recovered among all tenrec genera, allowing us to firmly establish the grouping of Geogale with Oryzorictinae, and to confirm the previously hypothesized nesting of Limnogale within the genus Microgale. The timeline of Malagasy tenrec diversification does not reflect a fast adaptive radiation after the arrival on Madagascar, indicating that morphological specializations have appeared over the whole evolutionary history of the family, and not just in a short period after colonization. In our analysis, age estimates at the root of a clade became older with increased taxon sampling of that clade. Moreover an augmentation of data partitions resulted in older age estimates as well, whereas standard deviations increased when more extreme partition schemes were used. Conclusion Our results provide as yet the best resolved gene tree comprising all Malagasy tenrec genera, and may lead to a revision of tenrec

  10. Exotic Mammal Laparoscopy.

    PubMed

    Sladakovic, Izidora; Divers, Stephen J

    2016-01-01

    Laparoscopy is an evolving field in veterinary medicine, and there is an increased interest in using laparoscopic techniques in nondomestic mammals, including zoo animals, wildlife, and exotic pets. The aim of this article is to summarize the approach to laparoscopic procedures, including instrumentation, patient selection and preparation, and surgical approaches, and to review the current literature on laparoscopy in exotic mammals.

  11. Prolonged food deprivation increases mRNA expression of deiodinase 1 and 2, and thyroid hormone receptor β-1 in a fasting-adapted mammal

    PubMed Central

    Martinez, Bridget; Soñanez-Organis, José G.; Vázquez-Medina, José Pablo; Viscarra, Jose A.; MacKenzie, Duncan S.; Crocker, Daniel E.; Ortiz, Rudy M.

    2013-01-01

    SUMMARY Food deprivation in mammals is typically associated with reduced thyroid hormone (TH) concentrations and deiodinase content and activity to suppress metabolism. However, in prolonged-fasted, metabolically active elephant seal pups, TH levels are maintained, if not elevated. The functional relevance of this apparent paradox is unknown and demonstrates variability in the regulation of TH levels, metabolism and function in food-deprived mammals. To address our hypothesis that cellular TH-mediated activity is upregulated with fasting duration, we quantified the mRNA expression and protein content of adipose and muscle deiodinase type I (DI1) and type II (DI2), and TH receptor beta-1 (THrβ-1) after 1, 3 and 7 weeks of fasting in northern elephant seal pups (N=5–7 per week). Fasting did not decrease the concentrations of plasma thyroid stimulating hormone, total triiodothyronine (tT3), free T3, total thyroxine (tT4) or free T4, suggesting that the hypothalamic–pituitary–thyroid axis is not suppressed, but rather maintained during fasting. Mean mRNA expression of adipose DI1 and DI2 increased threefold and fourfold, respectively, and 20- and 30-fold, respectively, in muscle. With the exception of adipose DI1, protein expression of adipose DI2 and muscle DI1 and DI2 increased twofold to fourfold. Fasting also increased adipose (fivefold) and muscle (fourfold) THrβ-1 mRNA expression, suggesting that the mechanisms mediating cellular TH activity are upregulated with prolonged fasting. The data demonstrate a unique, atypical mechanism of TH activity and regulation in mammals adapted to prolonged food deprivation in which the potential responsiveness of peripheral tissues and cellular TH activity are increased, which may contribute to their lipid-based metabolism. PMID:24307712

  12. Prolonged food deprivation increases mRNA expression of deiodinase 1 and 2, and thyroid hormone receptor β-1 in a fasting-adapted mammal.

    PubMed

    Martinez, Bridget; Soñanez-Organis, José G; Vázquez-Medina, José Pablo; Viscarra, Jose A; MacKenzie, Duncan S; Crocker, Daniel E; Ortiz, Rudy M

    2013-12-15

    Food deprivation in mammals is typically associated with reduced thyroid hormone (TH) concentrations and deiodinase content and activity to suppress metabolism. However, in prolonged-fasted, metabolically active elephant seal pups, TH levels are maintained, if not elevated. The functional relevance of this apparent paradox is unknown and demonstrates variability in the regulation of TH levels, metabolism and function in food-deprived mammals. To address our hypothesis that cellular TH-mediated activity is upregulated with fasting duration, we quantified the mRNA expression and protein content of adipose and muscle deiodinase type I (DI1) and type II (DI2), and TH receptor beta-1 (THrβ-1) after 1, 3 and 7 weeks of fasting in northern elephant seal pups (N=5-7 per week). Fasting did not decrease the concentrations of plasma thyroid stimulating hormone, total triiodothyronine (tT3), free T3, total thyroxine (tT4) or free T4, suggesting that the hypothalamic-pituitary-thyroid axis is not suppressed, but rather maintained during fasting. Mean mRNA expression of adipose DI1 and DI2 increased threefold and fourfold, respectively, and 20- and 30-fold, respectively, in muscle. With the exception of adipose DI1, protein expression of adipose DI2 and muscle DI1 and DI2 increased twofold to fourfold. Fasting also increased adipose (fivefold) and muscle (fourfold) THrβ-1 mRNA expression, suggesting that the mechanisms mediating cellular TH activity are upregulated with prolonged fasting. The data demonstrate a unique, atypical mechanism of TH activity and regulation in mammals adapted to prolonged food deprivation in which the potential responsiveness of peripheral tissues and cellular TH activity are increased, which may contribute to their lipid-based metabolism.

  13. Prolonged food deprivation increases mRNA expression of deiodinase 1 and 2, and thyroid hormone receptor β-1 in a fasting-adapted mammal.

    PubMed

    Martinez, Bridget; Soñanez-Organis, José G; Vázquez-Medina, José Pablo; Viscarra, Jose A; MacKenzie, Duncan S; Crocker, Daniel E; Ortiz, Rudy M

    2013-12-15

    Food deprivation in mammals is typically associated with reduced thyroid hormone (TH) concentrations and deiodinase content and activity to suppress metabolism. However, in prolonged-fasted, metabolically active elephant seal pups, TH levels are maintained, if not elevated. The functional relevance of this apparent paradox is unknown and demonstrates variability in the regulation of TH levels, metabolism and function in food-deprived mammals. To address our hypothesis that cellular TH-mediated activity is upregulated with fasting duration, we quantified the mRNA expression and protein content of adipose and muscle deiodinase type I (DI1) and type II (DI2), and TH receptor beta-1 (THrβ-1) after 1, 3 and 7 weeks of fasting in northern elephant seal pups (N=5-7 per week). Fasting did not decrease the concentrations of plasma thyroid stimulating hormone, total triiodothyronine (tT3), free T3, total thyroxine (tT4) or free T4, suggesting that the hypothalamic-pituitary-thyroid axis is not suppressed, but rather maintained during fasting. Mean mRNA expression of adipose DI1 and DI2 increased threefold and fourfold, respectively, and 20- and 30-fold, respectively, in muscle. With the exception of adipose DI1, protein expression of adipose DI2 and muscle DI1 and DI2 increased twofold to fourfold. Fasting also increased adipose (fivefold) and muscle (fourfold) THrβ-1 mRNA expression, suggesting that the mechanisms mediating cellular TH activity are upregulated with prolonged fasting. The data demonstrate a unique, atypical mechanism of TH activity and regulation in mammals adapted to prolonged food deprivation in which the potential responsiveness of peripheral tissues and cellular TH activity are increased, which may contribute to their lipid-based metabolism. PMID:24307712

  14. Mean Annual Precipitation Explains Spatiotemporal Patterns of Cenozoic Mammal Beta Diversity and Latitudinal Diversity Gradients in North America

    PubMed Central

    Fraser, Danielle; Hassall, Christopher; Gorelick, Root; Rybczynski, Natalia

    2014-01-01

    Spatial diversity patterns are thought to be driven by climate-mediated processes. However, temporal patterns of community composition remain poorly studied. We provide two complementary analyses of North American mammal diversity, using (i) a paleontological dataset (2077 localities with 2493 taxon occurrences) spanning 21 discrete subdivisions of the Cenozoic based on North American Land Mammal Ages (36 Ma – present), and (ii) climate space model predictions for 744 extant mammals under eight scenarios of future climate change. Spatial variation in fossil mammal community structure (β diversity) is highest at intermediate values of continental mean annual precipitation (MAP) estimated from paleosols (∼450 mm/year) and declines under both wetter and drier conditions, reflecting diversity patterns of modern mammals. Latitudinal gradients in community change (latitudinal turnover gradients, aka LTGs) increase in strength through the Cenozoic, but also show a cyclical pattern that is significantly explained by MAP. In general, LTGs are weakest when continental MAP is highest, similar to modern tropical ecosystems in which latitudinal diversity gradients are weak or undetectable. Projections under modeled climate change show no substantial change in β diversity or LTG strength for North American mammals. Our results suggest that similar climate-mediated mechanisms might drive spatial and temporal patterns of community composition in both fossil and extant mammals. We also provide empirical evidence that the ecological processes on which climate space models are based are insufficient for accurately forecasting long-term mammalian response to anthropogenic climate change and inclusion of historical parameters may be essential. PMID:25203658

  15. Mean annual precipitation explains spatiotemporal patterns of Cenozoic mammal beta diversity and latitudinal diversity gradients in North America.

    PubMed

    Fraser, Danielle; Hassall, Christopher; Gorelick, Root; Rybczynski, Natalia

    2014-01-01

    Spatial diversity patterns are thought to be driven by climate-mediated processes. However, temporal patterns of community composition remain poorly studied. We provide two complementary analyses of North American mammal diversity, using (i) a paleontological dataset (2077 localities with 2493 taxon occurrences) spanning 21 discrete subdivisions of the Cenozoic based on North American Land Mammal Ages (36 Ma--present), and (ii) climate space model predictions for 744 extant mammals under eight scenarios of future climate change. Spatial variation in fossil mammal community structure (β diversity) is highest at intermediate values of continental mean annual precipitation (MAP) estimated from paleosols (∼ 450 mm/year) and declines under both wetter and drier conditions, reflecting diversity patterns of modern mammals. Latitudinal gradients in community change (latitudinal turnover gradients, aka LTGs) increase in strength through the Cenozoic, but also show a cyclical pattern that is significantly explained by MAP. In general, LTGs are weakest when continental MAP is highest, similar to modern tropical ecosystems in which latitudinal diversity gradients are weak or undetectable. Projections under modeled climate change show no substantial change in β diversity or LTG strength for North American mammals. Our results suggest that similar climate-mediated mechanisms might drive spatial and temporal patterns of community composition in both fossil and extant mammals. We also provide empirical evidence that the ecological processes on which climate space models are based are insufficient for accurately forecasting long-term mammalian response to anthropogenic climate change and inclusion of historical parameters may be essential. PMID:25203658

  16. Mean annual precipitation explains spatiotemporal patterns of Cenozoic mammal beta diversity and latitudinal diversity gradients in North America.

    PubMed

    Fraser, Danielle; Hassall, Christopher; Gorelick, Root; Rybczynski, Natalia

    2014-01-01

    Spatial diversity patterns are thought to be driven by climate-mediated processes. However, temporal patterns of community composition remain poorly studied. We provide two complementary analyses of North American mammal diversity, using (i) a paleontological dataset (2077 localities with 2493 taxon occurrences) spanning 21 discrete subdivisions of the Cenozoic based on North American Land Mammal Ages (36 Ma--present), and (ii) climate space model predictions for 744 extant mammals under eight scenarios of future climate change. Spatial variation in fossil mammal community structure (β diversity) is highest at intermediate values of continental mean annual precipitation (MAP) estimated from paleosols (∼ 450 mm/year) and declines under both wetter and drier conditions, reflecting diversity patterns of modern mammals. Latitudinal gradients in community change (latitudinal turnover gradients, aka LTGs) increase in strength through the Cenozoic, but also show a cyclical pattern that is significantly explained by MAP. In general, LTGs are weakest when continental MAP is highest, similar to modern tropical ecosystems in which latitudinal diversity gradients are weak or undetectable. Projections under modeled climate change show no substantial change in β diversity or LTG strength for North American mammals. Our results suggest that similar climate-mediated mechanisms might drive spatial and temporal patterns of community composition in both fossil and extant mammals. We also provide empirical evidence that the ecological processes on which climate space models are based are insufficient for accurately forecasting long-term mammalian response to anthropogenic climate change and inclusion of historical parameters may be essential.

  17. Foundational issues concerning taxa and taxon names.

    PubMed

    Ereshefsky, Marc

    2007-04-01

    In a series of articles, Rieppel (2005, Biol. Philos. 20:465-487; 2006a, Cladistics 22:186-197; 2006b, Systematist 26:5-9), Keller et al. (2003, Bot. Rev. 69:93-110), and Nixon and Carpenter (2000, Cladistics 16:298-318) criticize the philosophical foundations of the PhyloCode. They argue that species and higher taxa are not individuals, and they reject the view that taxon names are rigid designators. Furthermore, they charge supporters of the individuality thesis and rigid designator theory with assuming essentialism, committing logical inconsistencies, and offering proposals that render taxonomy untestable. These charges are unsound. Such charges turn on confusions over rigid designator theory and the distinction between kinds and individuals. In addition, Rieppel's, Keller et al.'s, and Nixon and Carpenter's proposed alternatives are no better and have their own problems. The individuality thesis and rigid designator theory should not be quickly abandoned. PMID:17464884

  18. Increased brain size in mammals is associated with size variations in gene families with cell signalling, chemotaxis and immune-related functions.

    PubMed

    Castillo-Morales, Atahualpa; Monzón-Sandoval, Jimena; Urrutia, Araxi O; Gutiérrez, Humberto

    2014-01-22

    Genomic determinants underlying increased encephalization across mammalian lineages are unknown. Whole genome comparisons have revealed large and frequent changes in the size of gene families, and it has been proposed that these variations could play a major role in shaping morphological and physiological differences among species. Using a genome-wide comparative approach, we examined changes in gene family size (GFS) and degree of encephalization in 39 fully sequenced mammalian species and found a significant over-representation of GFS variations in line with increased encephalization in mammals. We found that this relationship is not accounted for by known correlates of brain size such as maximum lifespan or body size and is not explained by phylogenetic relatedness. Genes involved in chemotaxis, immune regulation and cell signalling-related functions are significantly over-represented among those gene families most highly correlated with encephalization. Genes within these families are prominently expressed in the human brain, particularly the cortex, and organized in co-expression modules that display distinct temporal patterns of expression in the developing cortex. Our results suggest that changes in GFS associated with encephalization represent an evolutionary response to the specific functional requirements underlying increased brain size in mammals.

  19. Novel symptomatology and changing epidemiology of domoic acid toxicosis in California sea lions (Zalophus californianus): an increasing risk to marine mammal health

    PubMed Central

    Goldstein, T; Mazet, J.A.K; Zabka, T.S; Langlois, G; Colegrove, K.M; Silver, M; Bargu, S; Van Dolah, F; Leighfield, T; Conrad, P.A; Barakos, J; Williams, D.C; Dennison, S; Haulena, M; Gulland, F.M.D

    2007-01-01

    Harmful algal blooms are increasing worldwide, including those of Pseudo-nitzschia spp. producing domoic acid off the California coast. This neurotoxin was first shown to cause mortality of marine mammals in 1998. A decade of monitoring California sea lion (Zalophus californianus) health since then has indicated that changes in the symptomatology and epidemiology of domoic acid toxicosis in this species are associated with the increase in toxigenic blooms. Two separate clinical syndromes now exist: acute domoic acid toxicosis as has been previously documented, and a second novel neurological syndrome characterized by epilepsy described here associated with chronic consequences of previous sub-lethal exposure to the toxin. This study indicates that domoic acid causes chronic damage to California sea lions and that these health effects are increasing. PMID:18006409

  20. Increased Expression of X-Linked Genes in Mammals Is Associated with a Higher Stability of Transcripts and an Increased Ribosome Density

    PubMed Central

    Faucillion, Marie-Line; Larsson, Jan

    2015-01-01

    Mammalian sex chromosomes evolved from the degeneration of one homolog of a pair of ancestral autosomes, the proto-Y. This resulted in a gene dose imbalance that is believed to be restored (partially or fully) through upregulation of gene expression from the single active X-chromosome in both sexes by a dosage compensatory mechanism. We analyzed multiple genome-wide RNA stability data sets and found significantly longer average half-lives for X-chromosome transcripts than for autosomal transcripts in various human cell lines, both male and female, and in mice. Analysis of ribosome profiling data shows that ribosome density is higher on X-chromosome transcripts than on autosomal transcripts in both humans and mice, suggesting that the higher stability is causally linked to a higher translation rate. Our results and observations are in accordance with a dosage compensatory upregulation of expressed X-linked genes. We therefore propose that differential mRNA stability and translation rates of the autosomes and sex chromosomes contribute to an evolutionarily conserved dosage compensation mechanism in mammals. PMID:25786432

  1. A new phylogeny for basal Trechnotheria and Cladotheria and affinities of South American endemic Late Cretaceous mammals.

    PubMed

    Averianov, Alexander O; Martin, Thomas; Lopatin, Alexey V

    2013-04-01

    The endemic South American mammals Meridiolestida, considered previously as dryolestoid cladotherians, are found to be non-cladotherian trechnotherians related to spalacotheriid symmetrodontans based on a parsimony analysis of 137 morphological characters among 44 taxa. Spalacotheriidae is the sister taxon to Meridiolestida, and the latter clade is derived from a primitive spalacolestine that migrated to South America from North America at the beginning of the Late Cretaceous. Meridiolestida survived until the early Paleocene (Peligrotherium) and early Miocene (Necrolestes) in South America, and their extinction is probably linked to the increasing competition with metatherian and eutherian tribosphenic mammals. The clade Meridiolestida plus Spalacotheriidae is the sister taxon to Cladotheria and forms a new clade Alethinotheria. Alethinotheria and its sister taxon Zhangheotheria, new clade (Zhangheotheriidae plus basal taxa), comprise Trechnotheria. Cladotheria is divided into Zatheria (plus stem taxa, including Amphitherium) and Dryolestida, including Dryolestidae and a paraphyletic array of basal dryolestidans (formerly classified as "Paurodontidae"). The South American Vincelestes and Groebertherium are basal dryolestidans. PMID:23494201

  2. Interaction between Locale and Taxon Strategies in Human Spatial Learning

    ERIC Educational Resources Information Center

    Redhead, Edward S.; Hamilton, Derek A.

    2007-01-01

    Three computer-based experiments which tested human participants in a non-immersive virtual watermaze task sought to determine factors which dictate whether the presence of a visual platform disrupts locale learning and taxon learning. In Experiment 1, the visible platform disrupted locale but not taxon learning based on viewpoint-independent and…

  3. Marine Mammals.

    ERIC Educational Resources Information Center

    Meith, Nikki

    Marine mammals have not only fascinated and inspired human beings for thousands of years, but they also support a big business by providing flesh for sea-borne factories, sustaining Arctic lifestyles and traditions, and attracting tourists to ocean aquaria. While they are being harpooned, bludgeoned, shot, netted, and trained to jump through…

  4. Stimulating Myocardial Regeneration with Periostin Peptide in Large Mammals Improves Function Post-Myocardial Infarction but Increases Myocardial Fibrosis

    PubMed Central

    Ladage, Dennis; Yaniz-Galende, Elisa; Rapti, Kleopatra; Ishikawa, Kiyotake; Tilemann, Lisa; Shapiro, Scott; Takewa, Yoshiaki; Muller-Ehmsen, Jochen; Schwarz, Martin; Garcia, Mario J.; Sanz, Javier; Hajjar, Roger J.; Kawase, Yoshiaki

    2013-01-01

    Aims Mammalian myocardium has a finite but limited capacity to regenerate. Experimentally stimulating proliferation of cardiomyocytes with extracellular regeneration factors like periostin enhances cardiac repair in rodents. The aim of this study was to develop a safe method for delivering regeneration factors to the heart and to test the functional and structural effects of periostin peptide treatment in a large animal model of myocardial infarction (MI). Methods and Results We developed a controlled release system to deliver recombinant periostin peptide into the pericardial space. A single application of this method was performed two days after experimental MI in swine. Animals were randomly assigned to receive either saline or periostin peptide. Experimental groups were compared at baseline, day 2, 1 month and 3 months. Treatment with periostin peptide increased the EF from 31% to 41% and decreased by 22% the infarct size within 12 weeks. Periostin peptide-treated animals had newly formed myocardium strips within the infarct scar, leading to locally improved myocardial function. In addition the capillary density was increased in animals receiving periostin. However, periostin peptide treatment increased myocardial fibrosis in the remote region at one week and 12 weeks post-treatment. Conclusion Our study shows that myocardial regeneration through targeted peptides is possible. However, in the case of periostin the effects on cardiac fibrosis may limit its clinical application as a viable therapeutic strategy. PMID:23700403

  5. Diving mammals.

    PubMed

    Ponganis, Paul J

    2011-01-01

    The ability of diving mammals to forage at depth on a breath hold of air is dependent on gas exchange, both in the lung and in peripheral tissues. Anatomical and physiological adaptations in the respiratory system, cardiovascular system, blood and peripheral tissues contribute to the remarkable breath-hold capacities of these animals. The end results of these adaptations include efficient ventilation, enhanced oxygen storage, regulated transport and delivery of respiratory gases, extreme hypoxemic/ischemic tolerance, and pressure tolerance.

  6. Audubon Mammal Study Program.

    ERIC Educational Resources Information Center

    National Audubon Society, New York, NY.

    Included are an illustrated student reader, "The Story of Mammals," a leaders' guide, a large wall chart picturing 39 North American mammals, and a separate booklet describing the mammals on the wall chart. The student reader presents these main topics: What Is a Mammal?; How Mammals Differ From Each Other; Where, When, and How To Find Mammals;…

  7. Increasing levels of long-chain perfluorocarboxylic acids (PFCAs) in Arctic and North Atlantic marine mammals, 1984-2009.

    PubMed

    Rotander, Anna; Kärrman, Anna; van Bavel, Bert; Polder, Anuschka; Rigét, Frank; Auðunsson, Guðjón Atli; Víkingsson, Gísli; Gabrielsen, Geir Wing; Bloch, Dorete; Dam, Maria

    2012-01-01

    Temporal variations in concentrations of perfluorinated carboxylic acids (PFCAs) and sulfonic acids (PFSAs), including perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) structural isomers, were examined in livers of pilot whale (Globicephala melas), ringed seal (Phoca hisida), minke whale (Balaenoptera acutorostrata), harbor porpoise (Phocoena phocoena), hooded seal (Cystophora cristata), Atlantic white-sided dolphin (Lagenorhynchus acutus) and in muscle tissue of fin whales (Balaenoptera physalus). The sampling spanned over 20 years (1984-2009) and covered a large geographical area of the North Atlantic and West Greenland. Liver and muscle samples were homogenized, extracted with acetonitrile, cleaned up using hexane and solid phase extraction (SPE), and analyzed by liquid chromatography with negative electrospray tandem mass spectrometry (LC-MS/MS). In general, the levels of the long-chained PFCAs (C9-C12) increased whereas the levels of PFOS remained steady over the studied period. The PFOS isomer pattern in pilot whale liver was relatively constant over the sampling years. However, in ringed seals there seemed to be a decrease in linear PFOS (L-PFOS) with time, going from 91% in 1984 to 83% in 2006. PMID:22051347

  8. Temporal, spatial and ecological dynamics of speciation among amphi-Beringian small mammals

    USGS Publications Warehouse

    Hope, Andrew G.; Takebayashi, Naoki; Galbreath, Kurt E.; Talbot, Sandra L.; Cook, Joseph A.

    2013-01-01

    Quaternary climate cycles played an important role in promoting diversification across the Northern Hemisphere, although details of the mechanisms driving evolutionary change are still poorly resolved. In a comparative phylogeographical framework, we investigate temporal, spatial and ecological components of evolution within a suite of Holarctic small mammals. We test a hypothesis of simultaneous divergence among multiple taxon pairs, investigating time to coalescence and demographic change for each taxon in response to a combination of climate and geography.

  9. Taxon-specific responses of Southern Ocean diatoms to Fe enrichment revealed by synchrotron radiation FTIR microspectroscopy

    NASA Astrophysics Data System (ADS)

    Sackett, O.; Armand, L.; Beardall, J.; Hill, R.; Doblin, M.; Connelly, C.; Howes, J.; Stuart, B.; Ralph, P.; Heraud, P.

    2014-10-01

    Photosynthesis by marine diatoms contributes substantially to global biogeochemical cycling and ecosystem productivity. It is widely accepted that diatoms are extremely sensitive to changes in Fe availability, with numerous in situ experiments demonstrating rapid growth and increased export of elements (e.g. C, Si and Fe) from surface waters as a result of Fe addition. Less is known about the effects of Fe enrichment on the phenotypes of diatoms, such as associated changes in nutritional value - furthermore, data on taxon-specific responses are almost non-existent. Enhanced supply of nutrient-rich waters along the coast of the subantarctic Kerguelen Island provide a valuable opportunity to examine the responses of phytoplankton to natural Fe enrichment. Here we demonstrate the use of synchrotron radiation Fourier Transform Infrared (SR-FTIR) microspectroscopy to analyse changes in the macromolecular composition of diatoms collected along the coast and plateau of Kerguelen Island, Southern Ocean. SR-FTIR microspectroscopy enabled the analysis of individual diatom cells from mixed communities of field-collected samples, thereby providing insight into in situ taxon-specific responses in relation to changes in Fe availability. Phenotypic responses were taxon-specific in terms of intraspecific variability and changes in proteins, amino acids, phosphorylated molecules, silicate/silicic acid and carbohydrates. In contrast to some previous studies, silicate/silicic acid levels increased under Fe enrichment, in conjunction with increases in carbohydrate stores. The highly abundant taxon Fragilariopsis kerguelensis displayed a higher level of phenotypic plasticity than Pseudo-nitzschia spp., while analysis of the data pooled across all measured taxa showed different patterns in macromolecular composition compared to those for individual taxon. This study demonstrates that taxon-specific responses to Fe enrichment may not always be accurately reflected by bulk community

  10. Taxon-specific responses of Southern Ocean diatoms to Fe enrichment revealed by synchrotron radiation FTIR microspectroscopy

    NASA Astrophysics Data System (ADS)

    Sackett, O.; Armand, L.; Beardall, J.; Hill, R.; Doblin, M.; Connelly, C.; Howes, J.; Stuart, B.; Ralph, P.; Heraud, P.

    2014-05-01

    Photosynthesis by marine diatoms contributes substantially to global biogeochemical cycling and ecosystem productivity. It is widely accepted that diatoms are extremely sensitive to changes in Fe availability, with numerous in situ experiments demonstrating rapid growth and increased export of elements (e.g. C, Si and Fe) from surface waters as a result of Fe addition. Less is known about the effects of Fe enrichment on the phenotypes of diatoms, such as associated changes in nutritional value, furthermore data on taxon-specific responses is almost non-existent. Enhanced supply of nutrient-rich waters along the coast of the subantarctic Kerguelen Island provide a valuable opportunity to examine the responses of phytoplankton to natural Fe enrichment. Here we demonstrate the use of synchrotron radiation Fourier Transform Infrared (SR-FTIR) microspectroscopy to analyse changes in the macromolecular composition of diatoms collected along the coast and plateau of Kerguelen Island, Southern Ocean. SR-FTIR microspectroscopy enabled the analysis of individual diatom cells from mixed communities of field-collected samples, thereby providing insight into in situ taxon-specific responses in relation to changes in Fe availability. Phenotypic responses were taxon-specific in terms of intraspecific variability and changes in proteins, amino acids, phosphorylated molecules, silicate and carbohydrates. In contrast to some previous studies, silicate levels increased under Fe enrichment, in conjunction with increases in carbohydrate stores. The highly abundant taxon Fragilariopsis kerguelensis displayed a higher level of phenotypic plasticity than Pseudo-nitzschia spp., while analysis of the data pooled across all measured taxa showed different patterns in macromolecular composition compared to those for individual taxon. This study demonstrates that taxon-specific responses to Fe enrichment may not always be accurately reflected by bulk community measurements, highlighting the

  11. Mitochondrial data are not suitable for resolving placental mammal phylogeny.

    PubMed

    Morgan, Claire C; Creevey, Christopher J; O'Connell, Mary J

    2014-12-01

    Mitochondrial data have traditionally been used in reconstructing a variety of species phylogenies. The low rates of recombination and thorough characterization of mitochondrial data across vertebrate species make it a particularly attractive phylogenetic marker. The relatively low number of fully sequenced mammal genomes and the lack of extensive sampling within Superorders have posed a serious problem for reaching agreement on the placement mammal species. The use of mitochondrial data sequences from large numbers of mammals could serve to circumvent the taxon-sampling deficit. Here we assess the suitability of mitochondrial data as a phylogenetic marker in mammal phylogenetics. MtDNA datasets of mammal origin have been filtered as follows: (i) we have sampled sparsely across the phylogenetic tree, (ii) we have constrained our sampling to genes with high taxon coverage, (iii) we have categorised rates across sites in a phylogeny independent manner and have removed fast evolving sites, and (iv), we have sampled from very shallow divergence times to reduce phylogenetic conflict. However, topologies obtained using these filters are not consistent with previous studies and are discordant across different genes. Individual mitochondrial genes, and indeed all mitochondrial genes analysed as a supermatrix, resulted in poor resolution of the species phylogeny. Overall, our study highlights the limitations of mitochondrial data, not only for resolving deep divergences and but also for shallow divergences in the mammal phylogeny.

  12. Mammals of the Sea.

    ERIC Educational Resources Information Center

    Naturescope, 1986

    1986-01-01

    Presents information on sea mammals, including definitions and characteristics of cetaceans, pinnipeds, and sirenians. Contains descriptions of the teaching activities "Whale Music,""Draw A Whale to Scale,""Adopt a Sea Mammal," and "Sea Mammal Sleuths." (TW)

  13. Increasing density leads to generalization in both coarse-grained habitat selection and fine-grained resource selection in a large mammal.

    PubMed

    van Beest, Floris M; Uzal, Antonio; Vander Wal, Eric; Laforge, Michel P; Contasti, Adrienne L; Colville, David; McLoughlin, Philip D

    2014-01-01

    Density is a fundamental driver of many ecological processes including habitat selection. Theory on density-dependent habitat selection predicts that animals should be distributed relative to profitability of habitat, resulting in reduced specialization in selection (i.e. generalization) as density increases and competition intensifies. Despite mounting empirical support for density-dependent habitat selection using isodars to describe coarse-grained (interhabitat) animal movements, we know little of how density affects fine-grained resource selection of animals within habitats [e.g. using resource selection functions (RSFs)]. Using isodars and RSFs, we tested whether density simultaneously modified habitat selection and within-habitat resource selection in a rapidly growing population of feral horses (Equus ferus caballus Linnaeus; Sable Island, Nova Scotia, Canada; 42% increase in population size from 2008 to 2012). Among three heterogeneous habitat zones on Sable Island describing population clusters distributed along a west-east resource gradient (west-central-east), isodars revealed that horses used available habitat in a density-dependent manner. Intercepts and slopes of isodars demonstrated a pattern of habitat selection that first favoured the west, which generalized to include central and east habitats with increasing population size consistent with our understanding of habitat quality on Sable Island. Resource selection functions revealed that horses selected for vegetation associations similarly at two scales of extent (total island and within-habitat zone). When densities were locally low, horses were able to select for sites of the most productive forage (grasslands) relative to those of poorer quality. However, as local carrying capacity was approached, selection for the best of available forage types weakened while selection for lower-quality vegetation increased (and eventually exceeded that of grasslands). Isodars can effectively describe coarse

  14. What Makes a Mammal a Mammal?

    ERIC Educational Resources Information Center

    Naturescope, 1986

    1986-01-01

    Describes the distinctive characteristics of mammals and compares modern mammals with their prehistoric relatives as well as with other animal groups. Includes activities and ready-to-copy games, illustrations, and diagrams of wolves, vertebrates, and past and present mammals. (ML)

  15. The first haramiyoid mammal from Asia

    NASA Astrophysics Data System (ADS)

    Maisch, Michael W.; Matzke, Andreas T.; Grossmann, Franziska; Stöhr, Henrik; Pfretzschner, Hans-Ulrich; Sun, Ge

    2005-01-01

    A lower molar of a haramiyoid mammal is described from the Toutunhe Formation of Liuhuanggou near Urumqi in the southern Junggar Basin, Xinjiang, China. It is referred to Eleutherodon sp., otherwise exclusively known from the Upper Bathonian of England. It is the first record of the order Haramiyida from Asia and the first Mesozoic mammal described from the southern Junggar Basin. Apart from the English specimens of Eleutherodon and Staffia from the Upper Jurassic of East Africa, it is the geologically youngest haramiyoid known. It is the first vertebrate taxon from the Toutunhe Formation that is probably not endemic and lends some support to the dating of the Formation as late Middle Jurassic, probably Bathonian.

  16. The Taxonic Latent Structure and Taxometrics in Forensic Mental Health.

    PubMed

    Maraun, Michael D; Hart, Stephen D

    2016-10-01

    Recently, researchers in the field of forensic mental health have attempted to address the technical, empirical question of whether important clinical problems, such as psychopathy or malingering, constitute taxa (i.e., discrete conditions). In this paper, we provide a detailed elucidation of the foundational logic of the quantitative methods employed to answer this question, focusing on the taxometric procedures developed by Paul Meehl and colleagues. We attempt to demonstrate that research on taxonicity is hampered by (a) researchers' unfamiliarity with or misunderstanding of the logic underlying latent variable technologies and (b) the fundamental incapacity of Meehlian procedures to provide a test of taxonicity. We conclude by discussing the utility of taxometric procedures to research in forensic mental health and, more broadly, in the field of applied psychological measurement.

  17. Blood lead concentrations in marine mammals validate estimates of 10{sup 2}- to 10{sup 3}-fold increase in human blood lead concentrations

    SciTech Connect

    Owen, B.D.; Flegal, A.R.

    1998-08-01

    Measurements of ultra-low ambient blood lead (PbB) concentrations (mean {+-} SD = 0.13 {+-} 0.06 {micro}g/dL) in Northern elephant seals (Mirounga angustirostris) validate previous estimates of ultra-low PbB levels in preindustrial humans. These estimates had been unsubstituted, since PbB levels in this range had never been measured in any organisms prior to this study. Similarities in PbB levels among these contemporary and preindustrial mammals are consistent with similarities in their measured and estimated lead exposures, respectively. The marginally higher PbB levels and rates of lead exposure in contemporary marine mammals are, also, consistent with lead isotopic composition analyses that indicate their PbB levels have been elevated from exposure to industrial lead. Consequently, these analyses substantiate concerns that current baseline PbB levels in humans, which are estimated to be two to three orders of magnitude above natural levels, may still constitute public health risks.

  18. Anterior commissure versus corpus callosum: A quantitative comparison across mammals.

    PubMed

    Ashwell, Ken W S

    2016-04-01

    Mammals rely on two major pathways to transfer information between the two hemispheres of the brain: the anterior commissure and the corpus callosum. Metatheria and monotremes rely exclusively on the anterior commissure for interhemispheric transfer between the isocortices and olfactory allocortices of each side, whereas Eutheria use a combination of the anterior commissure and an additional pathway exclusive to Eutheria, the corpus callosum. Midline cross-sectional area of the anterior commissure and corpus callosum were measured in a range of mammals from all three infraclasses and plotted against brain volume to determine how midline anterior commissure area and its size relative to the corpus callosum vary with brain size and taxon. In Metatheria, the square root of anterior commissure area rises in almost direct proportion with the cube root of brain volume (i.e. the ratio of the two is relatively constant), whereas among Eutheria the ratio of the square root of anterior commissure area to the cube root of brain volume declines slightly with increasing brain size. The total of isocortical and olfactory allocortical commissure area rises more rapidly with increasing brain volume among Eutheria than among Metatheria. This means that the midline isocortical and olfactory allocortical commissural area of metatherians with large brains (about 70 ml) is only about 50% of that among eutherians with similarly sized brains. On the other hand, isocortical and olfactory allocortical commissural area is similar in Metatheria and Eutheria at brain volumes around 1 ml. Among the Eutheria, some groups make less use of the anterior commissure pathway than do others: soricomorphs, rodents and cetaceans have smaller anterior commissures for their brain size than do afrosoricids, erinaceomorphs and proboscideans. The findings suggest that use of the anterior commissural route for isocortical commissural connections may have placed limitations on interhemispheric transfer of

  19. Anterior commissure versus corpus callosum: A quantitative comparison across mammals.

    PubMed

    Ashwell, Ken W S

    2016-04-01

    Mammals rely on two major pathways to transfer information between the two hemispheres of the brain: the anterior commissure and the corpus callosum. Metatheria and monotremes rely exclusively on the anterior commissure for interhemispheric transfer between the isocortices and olfactory allocortices of each side, whereas Eutheria use a combination of the anterior commissure and an additional pathway exclusive to Eutheria, the corpus callosum. Midline cross-sectional area of the anterior commissure and corpus callosum were measured in a range of mammals from all three infraclasses and plotted against brain volume to determine how midline anterior commissure area and its size relative to the corpus callosum vary with brain size and taxon. In Metatheria, the square root of anterior commissure area rises in almost direct proportion with the cube root of brain volume (i.e. the ratio of the two is relatively constant), whereas among Eutheria the ratio of the square root of anterior commissure area to the cube root of brain volume declines slightly with increasing brain size. The total of isocortical and olfactory allocortical commissure area rises more rapidly with increasing brain volume among Eutheria than among Metatheria. This means that the midline isocortical and olfactory allocortical commissural area of metatherians with large brains (about 70 ml) is only about 50% of that among eutherians with similarly sized brains. On the other hand, isocortical and olfactory allocortical commissural area is similar in Metatheria and Eutheria at brain volumes around 1 ml. Among the Eutheria, some groups make less use of the anterior commissure pathway than do others: soricomorphs, rodents and cetaceans have smaller anterior commissures for their brain size than do afrosoricids, erinaceomorphs and proboscideans. The findings suggest that use of the anterior commissural route for isocortical commissural connections may have placed limitations on interhemispheric transfer of

  20. [Jaws of primitive mammals].

    PubMed

    Tsubamoto, Takehisa

    2005-06-01

    Some of main osteological differences between mammals and reptiles are seen in the number of bones that constitute lower jaw and in jaw articulation. A lower jaw of mammals consists of only one bone, while in reptiles it consists of several bones (e.g., four to six in lizards and five in crocodiles). The jaw articulation in mammals is performed by squamosal of the skull and the mandible ( = dentary), while in reptiles it is done by quadrate of the skull and articular of the lower jaw. When mammals first appeared about 200 million years ago in the Mesozoic Era, the jaws of primitive mammals were morphologically intermediate between those of reptiles and typical mammals. Here, I briefly introduce the evolution of lower jaw morphology from the reptilian one to the mammalian one, showing lower jaw features of some mammal-like reptiles and primitive mammals.

  1. Protection of Marine Mammals.

    PubMed

    Knoll, Michaela; Ciaccia, Ettore; Dekeling, René; Kvadsheim, Petter; Liddell, Kate; Gunnarsson, Stig-Lennart; Ludwig, Stefan; Nissen, Ivor; Lorenzen, Dirk; Kreimeyer, Roman; Pavan, Gianni; Meneghetti, Nello; Nordlund, Nina; Benders, Frank; van der Zwan, Timo; van Zon, Tim; Fraser, Leanne; Johansson, Torbjörn; Garmelius, Martin

    2016-01-01

    Within the European Defense Agency (EDA), the Protection of Marine Mammals (PoMM) project, a comprehensive common marine mammal database essential for risk mitigation tools, was established. The database, built on an extensive dataset collection with the focus on areas of operational interest for European navies, consists of annual and seasonal distribution and density maps, random and systematic sightings, an encyclopedia providing knowledge on the characteristics of 126 marine mammal species, data on marine mammal protection areas, and audio information including numerous examples of various vocalizations. Special investigations on marine mammal acoustics were carried out to improve the detection and classification capabilities.

  2. Protection of Marine Mammals.

    PubMed

    Knoll, Michaela; Ciaccia, Ettore; Dekeling, René; Kvadsheim, Petter; Liddell, Kate; Gunnarsson, Stig-Lennart; Ludwig, Stefan; Nissen, Ivor; Lorenzen, Dirk; Kreimeyer, Roman; Pavan, Gianni; Meneghetti, Nello; Nordlund, Nina; Benders, Frank; van der Zwan, Timo; van Zon, Tim; Fraser, Leanne; Johansson, Torbjörn; Garmelius, Martin

    2016-01-01

    Within the European Defense Agency (EDA), the Protection of Marine Mammals (PoMM) project, a comprehensive common marine mammal database essential for risk mitigation tools, was established. The database, built on an extensive dataset collection with the focus on areas of operational interest for European navies, consists of annual and seasonal distribution and density maps, random and systematic sightings, an encyclopedia providing knowledge on the characteristics of 126 marine mammal species, data on marine mammal protection areas, and audio information including numerous examples of various vocalizations. Special investigations on marine mammal acoustics were carried out to improve the detection and classification capabilities. PMID:26611003

  3. Developing terrestrial, multi-taxon indices of biological integrity: An example from coastal sage scrub

    USGS Publications Warehouse

    Diffendorfer, J.E.; Fleming, G.M.; Duggan, J.M.; Chapman, R.E.; Rahn, M.E.; Mitrovich, M.J.; Fisher, R.N.

    2007-01-01

    We screened 351 species or genera for their response to disturbance in coastal sage scrub (CSS) to develop a 15-metric, 5-taxon Index of Biological Integrity (IBI). We collected data on ants, birds, herpetofauna, small mammals, and plants for two years on 46 sites established across a gradient of disturbance in three reserves. The gradient spanned relatively intact CSS with thick stands of shrubs, to former CSS stands type-converted to exotic grasses. ANOVAs and clustering analyses indicated the IBI could distinguish four levels of disturbance in CSS. General measures of community structure, such as richness, did not show changes across the gradient for most taxa, and responses of taxa across the gradient were varied and rarely correlated. However, turnover in species or genera across the gradient was common across all taxa as shrub-obligate life forms were replaced by those favoring grassy or disturbed habitats. Our data indicate index-based approaches based on data collected across disturbance gradients may outperform more traditional community level metrics when responses to anthropogenic influences are complex and vary across species. ?? 2007 Elsevier Ltd. All rights reserved.

  4. Body weight prediction in early fossil hominids: towards a taxon-"independent" approach.

    PubMed

    Hartwig-Scherer, S

    1993-09-01

    The choice of a model taxon is crucial when investigating fossil hominids that clearly do not resemble any extant species (such as Australopithecus) or show significant differences from modern human proportions (such as Homo habilis OH 62). An "interhominoid" combination is not adequate either, as scaling with body weight is strongly divergent in African apes and humans for most skeletal predictors investigated here. Therefore, in relation to a study of seven long bone dimensions, a new taxon-"independent" approach is suggested. For a given predictor, its taxonomic "independence" is restricted to the size range over which the body weight-predictor relationship for African apes and humans converges. Different predictors produce converging body weight estimates (BWEs) for different size ranges: taxon-"independent" estimates can be calculated for small- and medium-sized hominids (e.g., for weights below 50 kg) using femoral and tibial dimensions, whereas upper limb bones provide converging results for large hominids (above 50 kg). If the remains of Australopithecus afarensis really belong to one species, the relationship of male (above 60 kg) to female body weight (approximately 30 kg) does not fall within the observed range of modern hominoids. Considering Sts 14 (22 kg) to represent a small-sized Australopithecus africanus, the level of encephalization lies well above that of extant apes. If OH 62 (approximately 25 kg), with limb proportions less human-like than those of australopithecines, indeed represents Homo habilis (which has been questioned previously), an increase in relative brain size would have occurred well before full bipedality, an assumption running counter to current assumptions concerning early human evolution. PMID:8238289

  5. Lagenidium giganteum Pathogenicity in Mammals

    PubMed Central

    Vilela, Raquel; Taylor, John W.; Walker, Edward D.

    2015-01-01

    Infections of mammals by species in the phylum Oomycota taxonomically and molecularly similar to known Lagenidium giganteum strains have increased. During 2013–2014, we conducted a phylogenetic study of 21 mammalian Lagenidium isolates; we found that 11 cannot be differentiated from L. giganteum strains that the US Environmental Protection Agency approved for biological control of mosquitoes; these strains were later unregistered and are no longer available. L. giganteum strains pathogenic to mammals formed a strongly supported clade with the biological control isolates, and both types experimentally infected mosquito larvae. However, the strains from mammals grew well at 25°C and 37°C, whereas the biological control strains developed normally at 25°C but poorly at higher temperatures. The emergence of heat-tolerant strains of L. giganteum pathogenic to lower animals and humans is of environmental and public health concern. PMID:25625190

  6. A new symmetrodont mammal from China and its implications for mammalian evolution.

    PubMed

    Hu, Y; Wang, Y; Luo, Z; Li, C

    1997-11-13

    A new symmetrodont mammal has been discovered in the Mesozoic era (Late Jurassic or Early Cretaceous period) of Liaoning Province, China. Archaic therian mammals, including symmetrodonts, are extinct relatives of the living marsupial and placental therians. However, these archaic therians have been mostly documented by fragmentary fossils. This newfossil taxon, represented by a nearly complete postcranial skeleton and a partial skull with dentition, is the best-preserved symmetrodont mammal yet discovered. It provides a new insight into the relationships of the major lineages of mammals and the evolution of the mammalian skeleton. Our analysis suggests that this new taxon represents a part of the early therian radiation before the divergence of living marsupials and placentals; that therians and multituberculates are more closely related to each other than either group is to other mammalian lineages; that archaic therians lacked the more parasagittal posture of the forelimb of most living therian mammals; and that archaic therians, such as symmetrodonts, retained the primitive feature of a finger-like promontorium (possibly with a straight cochlea) of the non-therian mammals. The fully coiled cochlea evolved later in more derived therian mammals, and is therefore convergent to the partially coiled cochlea of monotremes. PMID:9367151

  7. A new symmetrodont mammal from China and its implications for mammalian evolution.

    PubMed

    Hu, Y; Wang, Y; Luo, Z; Li, C

    1997-11-13

    A new symmetrodont mammal has been discovered in the Mesozoic era (Late Jurassic or Early Cretaceous period) of Liaoning Province, China. Archaic therian mammals, including symmetrodonts, are extinct relatives of the living marsupial and placental therians. However, these archaic therians have been mostly documented by fragmentary fossils. This newfossil taxon, represented by a nearly complete postcranial skeleton and a partial skull with dentition, is the best-preserved symmetrodont mammal yet discovered. It provides a new insight into the relationships of the major lineages of mammals and the evolution of the mammalian skeleton. Our analysis suggests that this new taxon represents a part of the early therian radiation before the divergence of living marsupials and placentals; that therians and multituberculates are more closely related to each other than either group is to other mammalian lineages; that archaic therians lacked the more parasagittal posture of the forelimb of most living therian mammals; and that archaic therians, such as symmetrodonts, retained the primitive feature of a finger-like promontorium (possibly with a straight cochlea) of the non-therian mammals. The fully coiled cochlea evolved later in more derived therian mammals, and is therefore convergent to the partially coiled cochlea of monotremes.

  8. A Standardized Reference Data Set for Vertebrate Taxon Name Resolution.

    PubMed

    Zermoglio, Paula F; Guralnick, Robert P; Wieczorek, John R

    2016-01-01

    Taxonomic names associated with digitized biocollections labels have flooded into repositories such as GBIF, iDigBio and VertNet. The names on these labels are often misspelled, out of date, or present other problems, as they were often captured only once during accessioning of specimens, or have a history of label changes without clear provenance. Before records are reliably usable in research, it is critical that these issues be addressed. However, still missing is an assessment of the scope of the problem, the effort needed to solve it, and a way to improve effectiveness of tools developed to aid the process. We present a carefully human-vetted analysis of 1000 verbatim scientific names taken at random from those published via the data aggregator VertNet, providing the first rigorously reviewed, reference validation data set. In addition to characterizing formatting problems, human vetting focused on detecting misspelling, synonymy, and the incorrect use of Darwin Core. Our results reveal a sobering view of the challenge ahead, as less than 47% of name strings were found to be currently valid. More optimistically, nearly 97% of name combinations could be resolved to a currently valid name, suggesting that computer-aided approaches may provide feasible means to improve digitized content. Finally, we associated names back to biocollections records and fit logistic models to test potential drivers of issues. A set of candidate variables (geographic region, year collected, higher-level clade, and the institutional digitally accessible data volume) and their 2-way interactions all predict the probability of records having taxon name issues, based on model selection approaches. We strongly encourage further experiments to use this reference data set as a means to compare automated or computer-aided taxon name tools for their ability to resolve and improve the existing wealth of legacy data.

  9. A Standardized Reference Data Set for Vertebrate Taxon Name Resolution

    PubMed Central

    Zermoglio, Paula F.; Guralnick, Robert P.; Wieczorek, John R.

    2016-01-01

    Taxonomic names associated with digitized biocollections labels have flooded into repositories such as GBIF, iDigBio and VertNet. The names on these labels are often misspelled, out of date, or present other problems, as they were often captured only once during accessioning of specimens, or have a history of label changes without clear provenance. Before records are reliably usable in research, it is critical that these issues be addressed. However, still missing is an assessment of the scope of the problem, the effort needed to solve it, and a way to improve effectiveness of tools developed to aid the process. We present a carefully human-vetted analysis of 1000 verbatim scientific names taken at random from those published via the data aggregator VertNet, providing the first rigorously reviewed, reference validation data set. In addition to characterizing formatting problems, human vetting focused on detecting misspelling, synonymy, and the incorrect use of Darwin Core. Our results reveal a sobering view of the challenge ahead, as less than 47% of name strings were found to be currently valid. More optimistically, nearly 97% of name combinations could be resolved to a currently valid name, suggesting that computer-aided approaches may provide feasible means to improve digitized content. Finally, we associated names back to biocollections records and fit logistic models to test potential drivers of issues. A set of candidate variables (geographic region, year collected, higher-level clade, and the institutional digitally accessible data volume) and their 2-way interactions all predict the probability of records having taxon name issues, based on model selection approaches. We strongly encourage further experiments to use this reference data set as a means to compare automated or computer-aided taxon name tools for their ability to resolve and improve the existing wealth of legacy data. PMID:26760296

  10. A Standardized Reference Data Set for Vertebrate Taxon Name Resolution.

    PubMed

    Zermoglio, Paula F; Guralnick, Robert P; Wieczorek, John R

    2016-01-01

    Taxonomic names associated with digitized biocollections labels have flooded into repositories such as GBIF, iDigBio and VertNet. The names on these labels are often misspelled, out of date, or present other problems, as they were often captured only once during accessioning of specimens, or have a history of label changes without clear provenance. Before records are reliably usable in research, it is critical that these issues be addressed. However, still missing is an assessment of the scope of the problem, the effort needed to solve it, and a way to improve effectiveness of tools developed to aid the process. We present a carefully human-vetted analysis of 1000 verbatim scientific names taken at random from those published via the data aggregator VertNet, providing the first rigorously reviewed, reference validation data set. In addition to characterizing formatting problems, human vetting focused on detecting misspelling, synonymy, and the incorrect use of Darwin Core. Our results reveal a sobering view of the challenge ahead, as less than 47% of name strings were found to be currently valid. More optimistically, nearly 97% of name combinations could be resolved to a currently valid name, suggesting that computer-aided approaches may provide feasible means to improve digitized content. Finally, we associated names back to biocollections records and fit logistic models to test potential drivers of issues. A set of candidate variables (geographic region, year collected, higher-level clade, and the institutional digitally accessible data volume) and their 2-way interactions all predict the probability of records having taxon name issues, based on model selection approaches. We strongly encourage further experiments to use this reference data set as a means to compare automated or computer-aided taxon name tools for their ability to resolve and improve the existing wealth of legacy data. PMID:26760296

  11. Health risks for marine mammal workers.

    PubMed

    Hunt, Tania D; Ziccardi, Michael H; Gulland, Frances M D; Yochem, Pamela K; Hird, David W; Rowles, Teresa; Mazet, Jonna A K

    2008-08-19

    Marine mammals can be infected with zoonotic pathogens and show clinical signs of disease, or be asymptomatic carriers of such disease agents. While isolated cases of human disease from contact with marine mammals have been reported, no evaluation of the risks associated with marine mammal work has been attempted. Therefore, we designed a survey to estimate the risk of work-related injuries and illnesses in marine mammal workers and volunteers. The 17-question survey asked respondents to describe their contact with marine mammals, injuries sustained, and/or illnesses acquired during their period of marine mammal exposure. Most respondents, 88% (423/483), were researchers and rehabilitators. Of all respondents, 50% (243/483) reported suffering an injury caused by a marine mammal, and 23% (110/483) reported having a skin rash or reaction. Marine mammal work-related illnesses commonly reported included: 'seal finger' (Mycoplasma spp. or Erysipelothrix rhusiopathiae), conjunctivitis, viral dermatitis, bacterial dermatitis, and non-specific contact dermatitis. Although specific diagnoses could not be confirmed by a physician through this study, severe illnesses were reported and included tuberculosis, leptospirosis, brucellosis, and serious sequelae to seal finger. Risk factors associated with increased odds of injury and illness included prolonged and frequent exposure to marine mammals; direct contact with live marine mammals; and contact with tissue, blood, and excretions. Diagnosis of zoonotic disease was often aided by veterinarians; therefore, workers at risk should be encouraged to consult with a marine mammal veterinarian as well as a physician, especially if obtaining a definitive diagnosis for an illness becomes problematic.

  12. The impact of fossils and taxon sampling on ancient molecular dating analyses.

    PubMed

    Hug, Laura A; Roger, Andrew J

    2007-08-01

    The number and complexity of molecular dating studies has increased over the past decade. Along with a broadening acceptance of their utility has come significant controversy over the methods and models that are appropriate, as well as the accuracy of the estimates yielded by molecular clock analyses. Radically different age estimates have been published for the same divergences from analyses of different datasets with different fossil constraints obtained with different methods, and the underlying explanation for these differences is often unclear. Here we utilize two previously published datasets to examine the effect of fossil calibrations and taxon sampling on the age estimates for two deep eukaryote divergences in an attempt to discern the relative impact of these factors. Penalized likelihood, non-parametric rate smoothing, and Bayesian methods were utilized to generate age estimates for the origin of the Metazoa from a 7-gene dataset and for the divergence of Eukaryotes from a 129-gene dataset. From these analyses, it is clear that the fossil calibrations chosen and the method for applying constraints to these nodes have a large impact on age estimates, while the degree of taxon sampling within a dataset is less important in terms of the resulting age estimates. Concerns and recommendations for addressing these two factors when initiating a dating analysis are discussed.

  13. Mammals in Our Lives.

    ERIC Educational Resources Information Center

    Naturescope, 1986

    1986-01-01

    Examines how humans have treated mammals throughout history. Identifies both the problems facing animals and the corrective efforts that are currently underway. Student activities include stories, games, a scavenger hunt, a mural, a puzzle, and a survey focusing on mammals. (ML)

  14. Allometry in dinosaurs and mammals

    NASA Astrophysics Data System (ADS)

    Lee, Scott

    2015-03-01

    The proportions of the leg bones change as the size of an animal becomes larger since the mass of the animal increases at a faster rate than the cross-sectional area of its leg bones. For the case of elastic similarity (in which the longitudinal stress in the legs remains constant in animals of all sizes), the diameter d and length L of the femur should be related as d = A L3/2. For geometric similarity (in which all dimensions are scaled by the same factor), d = A L. For animals with femora longer than 20 cm, we find the power law relationship to be d = A Lb with b = 1.13 +/- 0.06 for extant mammals (the largest mammal being Loxodonta africana with a 1.00-m-long femur) and b = 1.18 +/- 0.02 for dinosaurs (the largest dinosaur being Brachiosaurus brancai with a 2.03-m-long femur). These data show that extinct dinosaurs and extant animals scale in the same basic manner. The large sauropods (with femora twice as long as found in elephants) scale in a manner consistent with extrapolation of the scaling shown by extant mammals. These results argue that extinct dinosaurs moved in a manner very similar to extant mammals.

  15. Oxymonads are closely related to the excavate taxon Trimastix.

    PubMed

    Dacks, J B; Silberman, J D; Simpson, A G; Moriya, S; Kudo, T; Ohkuma, M; Redfield, R J

    2001-06-01

    Despite intensive study in recent years, large-scale eukaryote phylogeny remains poorly resolved. This is particularly problematic among the groups considered to be potential early branches. In many recent systematic schemes for early eukaryotic evolution, the amitochondriate protists oxymonads and Trimastix have figured prominently, having been suggested as members of many of the putative deep-branching higher taxa. However, they have never before been proposed as close relatives of each other. We amplified, cloned, and sequenced small-subunit ribosomal RNA genes from the oxymonad Pyrsonympha and from several Trimastix isolates. Rigorous phylogenetic analyses indicate that these two protist groups are sister taxa and are not clearly related to any currently established eukaryotic lineages. This surprising result has important implications for our understanding of cellular evolution and high-level eukaryotic phylogeny. Given that Trimastix contains small, electron-dense bodies strongly suspected to be derived mitochondria, this study constitutes the best evidence to date that oxymonads are not primitively amitochondriate. Instead, Trimastix and oxymonads may be useful organisms for investigations into the evolution of the secondary amitochondriate condition. All higher taxa involving either oxymonads or Trimastix may require modification or abandonment. Affected groups include four contemporary taxa given the rank of phylum (Metamonada, Loukozoa, Trichozoa, Percolozoa), and the informal excavate taxa. A new "phylum-level" taxon may be warranted for oxymonads and Trimastix. PMID:11371592

  16. Oxymonads are closely related to the excavate taxon Trimastix.

    PubMed

    Dacks, J B; Silberman, J D; Simpson, A G; Moriya, S; Kudo, T; Ohkuma, M; Redfield, R J

    2001-06-01

    Despite intensive study in recent years, large-scale eukaryote phylogeny remains poorly resolved. This is particularly problematic among the groups considered to be potential early branches. In many recent systematic schemes for early eukaryotic evolution, the amitochondriate protists oxymonads and Trimastix have figured prominently, having been suggested as members of many of the putative deep-branching higher taxa. However, they have never before been proposed as close relatives of each other. We amplified, cloned, and sequenced small-subunit ribosomal RNA genes from the oxymonad Pyrsonympha and from several Trimastix isolates. Rigorous phylogenetic analyses indicate that these two protist groups are sister taxa and are not clearly related to any currently established eukaryotic lineages. This surprising result has important implications for our understanding of cellular evolution and high-level eukaryotic phylogeny. Given that Trimastix contains small, electron-dense bodies strongly suspected to be derived mitochondria, this study constitutes the best evidence to date that oxymonads are not primitively amitochondriate. Instead, Trimastix and oxymonads may be useful organisms for investigations into the evolution of the secondary amitochondriate condition. All higher taxa involving either oxymonads or Trimastix may require modification or abandonment. Affected groups include four contemporary taxa given the rank of phylum (Metamonada, Loukozoa, Trichozoa, Percolozoa), and the informal excavate taxa. A new "phylum-level" taxon may be warranted for oxymonads and Trimastix.

  17. 7 CFR 360.501 - Petitions to remove a taxon from the noxious weed lists.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Petitions to remove a taxon from the noxious weed...) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.501 Petitions to remove a taxon from the noxious weed lists. A person may petition the Administrator to remove...

  18. 7 CFR 360.500 - Petitions to add a taxon to the noxious weed list.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Petitions to add a taxon to the noxious weed list. 360... PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.500 Petitions to add a taxon to the noxious weed list. A person may petition the Administrator to have a...

  19. 7 CFR 360.500 - Petitions to add a taxon to the noxious weed list.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Petitions to add a taxon to the noxious weed list. 360... PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.500 Petitions to add a taxon to the noxious weed list. A person may petition the Administrator to have a...

  20. 7 CFR 360.500 - Petitions to add a taxon to the noxious weed list.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Petitions to add a taxon to the noxious weed list. 360... PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.500 Petitions to add a taxon to the noxious weed list. A person may petition the Administrator to have a...

  1. 7 CFR 360.501 - Petitions to remove a taxon from the noxious weed lists.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Petitions to remove a taxon from the noxious weed...) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.501 Petitions to remove a taxon from the noxious weed lists. A person may petition the Administrator to remove...

  2. 7 CFR 360.500 - Petitions to add a taxon to the noxious weed list.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Petitions to add a taxon to the noxious weed list. 360... PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS § 360.500 Petitions to add a taxon to the noxious weed list. A person may petition the Administrator to have a...

  3. Ecotoxicology of wild mammals

    USGS Publications Warehouse

    Rattner, B.A.; Shore, R.F.

    2000-01-01

    An international group of 32 scientists has critically reviewed the scientific literature on exposure and effects of environmental contaminants in wild mammals. Although the absolute number of toxicological studies in domesticated and wild mammals eclipses that for birds, a detailed examination of scientific publications and databases reveal that information for 'wild' birds is actually greater than that for 'wild' mammals. Of the various taxa of mammals, ecotoxicological data is most noticeably lacking for marsupials and monotremes. In contrast, rodents (comprising 43% of all mammal species) have been studied extensively, despite evidence of their tolerance to some organochlorine compounds, rodenticides, and even radionuclides. Mammalian species at greatest risk of exposure include those that consume a high percentage of their body weight on a daily basis (e.g., shrews, moles and bats). Aquatic mammals tend to bioaccumulate tremendous burdens of lipophilic contaminants, although storage in their fat depots may actually limit toxicity. Carnivores appear to be more sensitive to adverse effects of environmental contaminants than herbivores. Remarkably few of the thousands of compounds manufactured worldwide have been toxicologically evaluated in wild mammals, and concentrations of even fewer have been monitored in tissues. Overarching research needs include: development of new exposure/effects models and better methods for estimation of species sensitivities; generation of comparative data on contaminant bioavailability, sublethal responses and detoxication mechanisms; enhanced understanding of pesticide, industrial contaminant and metal interactions; identification of endocrine disruptive contaminants and their overall ecological significance; and finally, estimating the relative contribution of environmental contamination as a factor affecting wild mammal populations.

  4. Differences in the umbrella effects of African amphibians and mammals based on two estimators of the area of occupancy.

    PubMed

    Rondinini, Carlo; Boitani, Luigi

    2006-02-01

    Conservation organizations are collecting large-scale data regarding distribution and threats to vertebrate taxa. These data sets will enable planners to systematically identify large-scale conservation priorities; however, they will cover only a tiny proportion of living organisms. Therefore, it is essential to investigate to what extent the areas selected for conservation actions can provide protection for other species. We analyzed the umbrella effect between amphibians and mammals across mainland Africa. We built habitat suitability models within the geographic ranges of 1654 species, based on data collected in the framework of the World Conservation Union (IUCN) Global Amphibian Assessment and IUCN Global Mammal Assessment. We applied systematic reserve selection algorithms to two sets of estimators of the area of occupancy of amphibians and mammals (geographic ranges and estimated suitable areas) and thus selected four reserve systems. We then quantified the protection that each of the four systems provided for amphibians and mammals. Reserves selected for amphibians and mammals were comparable in area, with the former concentrated in the Afrotropical region and the latter more evenly dispersed. Mammal reserves left fewer gaps in species coverage among amphibians than the reverse, but amphibian reserves included a larger proportion of each mammal's area of occupancy than the reverse. For both taxa, setting reserves to include estimated suitable areas instead of ranges resulted in the clustering of reserves in the tropics. Furthermore, it efficiently protected hidden gaps (species with unsuitable portions of their range inside protected areas) in the other taxon and included a higher proportion of the area of occupancy of the other taxon. Overall, amphibians and mammals in Africa acted as an umbrella for a high proportion of species in the other taxon. Focusing on estimated suitable areas instead of ranges improved the umbrella effect of both taxa.

  5. Recovery trends in marine mammal populations.

    PubMed

    Magera, Anna M; Mills Flemming, Joanna E; Kaschner, Kristin; Christensen, Line B; Lotze, Heike K

    2013-01-01

    Marine mammals have greatly benefitted from a shift from resource exploitation towards conservation. Often lauded as symbols of conservation success, some marine mammal populations have shown remarkable recoveries after severe depletions. Others have remained at low abundance levels, continued to decline, or become extinct or extirpated. Here we provide a quantitative assessment of (1) publicly available population-level abundance data for marine mammals worldwide, (2) abundance trends and recovery status, and (3) historic population decline and recent recovery. We compiled 182 population abundance time series for 47 species and identified major data gaps. In order to compare across the largest possible set of time series with varying data quality, quantity and frequency, we considered an increase in population abundance as evidence of recovery. Using robust log-linear regression over three generations, we were able to classify abundance trends for 92 spatially non-overlapping populations as Significantly Increasing (42%), Significantly Decreasing (10%), Non-Significant Change (28%) and Unknown (20%). Our results were comparable to IUCN classifications for equivalent species. Among different groupings, pinnipeds and other marine mammals (sirenians, polar bears and otters) showed the highest proportion of recovering populations, likely benefiting from relatively fast life histories and nearshore habitats that provided visibility and protective management measures. Recovery was less frequent among cetaceans, but more common in coastal than offshore populations. For marine mammals with available historical abundance estimates (n = 47), larger historical population declines were associated with low or variable recent recoveries so far. Overall, our results show that many formerly depleted marine mammal populations are recovering. However, data-deficient populations and those with decreasing and non-significant trends require attention. In particular, increased study of

  6. Recovery Trends in Marine Mammal Populations

    PubMed Central

    Magera, Anna M.; Mills Flemming, Joanna E.; Kaschner, Kristin; Christensen, Line B.; Lotze, Heike K.

    2013-01-01

    Marine mammals have greatly benefitted from a shift from resource exploitation towards conservation. Often lauded as symbols of conservation success, some marine mammal populations have shown remarkable recoveries after severe depletions. Others have remained at low abundance levels, continued to decline, or become extinct or extirpated. Here we provide a quantitative assessment of (1) publicly available population-level abundance data for marine mammals worldwide, (2) abundance trends and recovery status, and (3) historic population decline and recent recovery. We compiled 182 population abundance time series for 47 species and identified major data gaps. In order to compare across the largest possible set of time series with varying data quality, quantity and frequency, we considered an increase in population abundance as evidence of recovery. Using robust log-linear regression over three generations, we were able to classify abundance trends for 92 spatially non-overlapping populations as Significantly Increasing (42%), Significantly Decreasing (10%), Non-Significant Change (28%) and Unknown (20%). Our results were comparable to IUCN classifications for equivalent species. Among different groupings, pinnipeds and other marine mammals (sirenians, polar bears and otters) showed the highest proportion of recovering populations, likely benefiting from relatively fast life histories and nearshore habitats that provided visibility and protective management measures. Recovery was less frequent among cetaceans, but more common in coastal than offshore populations. For marine mammals with available historical abundance estimates (n = 47), larger historical population declines were associated with low or variable recent recoveries so far. Overall, our results show that many formerly depleted marine mammal populations are recovering. However, data-deficient populations and those with decreasing and non-significant trends require attention. In particular, increased

  7. Ecotoxicology of Wild Mammals

    USGS Publications Warehouse

    2001-01-01

    An international group of 32 scientists has critically reviewed the scientific literature on exposure and effects of environmental contaminants in wild mammals. The underlying theme of this text is encompassed by the following four questions: What exactly do we know about environmental contaminants in mammals? What are the commonalities and differences between mammal orders/species in the effects that contaminants have? How and to what degree of accuracy can we predict the adverse effects of environmental contaminants on mammalian wildlife? How significant are contaminant insults compared with other density-independent and -dependent factors such as habitat loss, climatic factors and disease? The book is organized three topical sections including introductory chapters that provide a background on environmental contaminants and the mammalian orders, eight taxonomic chapters discussing all aspects of the exposure to and effects of contaminants in mammalian orders, and four thematic chapters that review and discuss generic issues including biomarkers, prediction and extrapolation of exposure and effects, hazard and risk assessment, and the relative significance of contaminants on mammals compared with other commonly encountered stressors. A final a summary chapter identifies phylogenetic trends, critical data gaps, and overarching research needs. Although the absolute number of toxicological studies in domesticated and wild mammals eclipses that wildlife species, a detailed examination of our knowledge base reveals that information for 'wild' birds is actually greater than that for 'wild' mammals. Of the various mammalian taxa, ecotoxicological data is most noticeably lacking for marsupials and monotremes. In contrast, rodents (comprising 43% of all mammal species) have been studied extensively, despite evidence of their tolerance to some organochlorine compounds, rodenticides, and even radionuclides. Mammalian species at greatest risk of exposure include those that

  8. Osmoregulation in marine mammals

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.

    2001-01-01

    Osmoregulation in marine mammals has been investigated for over a century; however, a review of recent advances in our understanding of water and electrolyte balance and of renal function in marine mammals is warranted. The following topics are discussed: (i) kidney structure and urine concentrating ability, (ii) sources of water, (iii) the effects of feeding, fasting and diving, (iv) the renal responses to infusions of varying salinity and (v) hormonal regulation. The kidneys of pinnipeds and cetaceans are reniculate in structure, unlike those of terrestrial mammals (except bears), but this difference does not confer any greater concentrating ability. Pinnipeds, cetaceans, manatees and sea otters can concentrate their urine above the concentration of sea water, but only pinnipeds and otters have been shown to produce urine concentrations of Na+ and Cl- that are similar to those in sea water. This could afford them the capacity to drink sea water and not lose fresh water. However, with few exceptions, drinking is not a common behavior in pinnipeds and cetaceans. Water balance is maintained in these animals via metabolic and dietary water, while incidental ingestion and dietary salt may help maintain electrolyte homeostasis. Unlike most other aquatic mammals, sea otters commonly drink sea water and manatees frequently drink fresh water. Among the various taxonomic groups of marine mammals, the sensitivity of the renin-angiotensin-aldosterone system appears to be influenced by the availability of Na+. The antidiuretic role of vasopressin remains inconclusive in marine mammals, while the natriuretic function of atrial natriuretic peptide has yet to be examined. Ideas on the direction of future studies are presented.

  9. Venomous mammals: a review.

    PubMed

    Ligabue-Braun, Rodrigo; Verli, Hugo; Carlini, Célia Regina

    2012-06-01

    The occurrence of venom in mammals has long been considered of minor importance, but recent fossil discoveries and advances in experimental techniques have cast new light into this subject. Mammalian venoms form a heterogeneous group having different compositions and modes of action and are present in three classes of mammals, Insectivora, Monotremata, and Chiroptera. A fourth order, Primates, is proposed to have venomous representatives. In this review we highlight recent advances in the field while summarizing biochemical characteristics of these secretions and their effects upon humans and other animals. Historical aspects of venom discovery and evolutionary hypothesis regarding their origin are also discussed.

  10. Molecular phylogeny of living xenarthrans and the impact of character and taxon sampling on the placental tree rooting.

    PubMed

    Delsuc, Frédéric; Scally, Mark; Madsen, Ole; Stanhope, Michael J; de Jong, Wilfried W; Catzeflis, François M; Springer, Mark S; Douzery, Emmanuel J P

    2002-10-01

    Extant xenarthrans (armadillos, anteaters and sloths) are among the most derived placental mammals ever evolved. South America was the cradle of their evolutionary history. During the Tertiary, xenarthrans experienced an extraordinary radiation, whereas South America remained isolated from other continents. The 13 living genera are relics of this earlier diversification and represent one of the four major clades of placental mammals. Sequences of the three independent protein-coding nuclear markers alpha2B adrenergic receptor (ADRA2B), breast cancer susceptibility (BRCA1), and von Willebrand Factor (VWF) were determined for 12 of the 13 living xenarthran genera. Comparative evolutionary dynamics of these nuclear exons using a likelihood framework revealed contrasting patterns of molecular evolution. All codon positions of BRCA1 were shown to evolve in a strikingly similar manner, and third codon positions appeared less saturated within placentals than those of ADRA2B and VWF. Maximum likelihood and Bayesian phylogenetic analyses of a 47 placental taxa data set rooted by three marsupial outgroups resolved the phylogeny of Xenarthra with some evidence for two radiation events in armadillos and provided a strongly supported picture of placental interordinal relationships. This topology was fully compatible with recent studies, dividing placentals into the Southern Hemisphere clades Afrotheria and Xenarthra and a monophyletic Northern Hemisphere clade (Boreoeutheria) composed of Laurasiatheria and Euarchontoglires. Partitioned likelihood statistical tests of the position of the root, under different character partition schemes, identified three almost equally likely hypotheses for early placental divergences: a basal Afrotheria, an Afrotheria + Xenarthra clade, or a basal Xenarthra (Epitheria hypothesis). We took advantage of the extensive sampling realized within Xenarthra to assess its impact on the location of the root on the placental tree. By resampling taxa

  11. Mammals in Winter.

    ERIC Educational Resources Information Center

    Wapner, Suzanne

    1985-01-01

    Mammals that tolerate the winter cold and stay active all year exploit the harsh northern climate to their advantage. By simple experiments and observation you can better understand their adaptations which include furry bodies, snowshoe feet, extra blubber, light coloration, and strategically distributed food caches. (JHZ)

  12. Mammals With Hooves.

    ERIC Educational Resources Information Center

    Naturescope, 1986

    1986-01-01

    Presents information about mammals that have hooves, including definitions and descriptions of their characteristics. Contains teaching activities such as "Build a Paper Pachyderm,""Do the Funky Trunk Dance,""A Horse of a Different Color," and "Horns and Antlers." A reproducible quiz is also provided. (TW)

  13. Early Cretaceous mammal from North America and the evolution of marsupial dental characters.

    PubMed Central

    Cifelli, R L

    1993-01-01

    A mammal from the Early Cretaceous of the western United States, represented by a lower jaw exceptional in its completeness, presents unambiguous evidence of postcanine dental formula in an Early Cretaceous marsupial-like mammal, and prompts a reconsideration of the early evolution of marsupial dental characters. A marsupial postcanine dental formula (three premolars and four molars) and several marsupial-like features of the lower molars are present in the new taxon, but a hallmark specialization of marsupials (twinning of the hypoconulid and entoconid on lower molars) is lacking. This, coupled with recent evidence from the Late Cretaceous of the western United States, suggests that the distinctive marsupial dental formula evolved prior to the most characteristic specialization of lower molars and that apomorphies presumed to be diagnostic of the upper molars (such as auxiliary stylar cusps) were relatively more recent developments in marsupial history. Dental evidence supports the monophyly of higher (tribosphenic) mammals and suggests that the predominantly Old World Deltatheroida, recently proposed as a sister taxon to marsupials, represents a primitive and unrelated group of higher mammals; by this interpretation, early marsupials and their presumed close relatives are restricted to North America. This, together with the hypothesized relationships of South American/Australian marsupials (in the context of the North American Cretaceous radiation) and evidence from the fossil record of South America, in turn supports a North American origin for the group. Images Fig. 1 PMID:8415715

  14. The genus Nonomuraea: A review of a rare actinomycete taxon for novel metabolites.

    PubMed

    Sungthong, Rungroch; Nakaew, Nareeluk

    2015-05-01

    The genus Nonomuraea is a rare actinomycete taxon with a long taxonomic history, while its generic description was recently emended. The genus is less known among the rare actinomycete genera as its taxonomic position was revised several times. It can be found in diverse ecological niches, while most of its member species were isolated from soil samples. However, new trends to discover the genus in other habitats are increasing. Generic abundance of the genus was found to be dependent on geographical changes. Novel sources together with selective and invented isolation techniques might increase a chance to explore the genus and its novel candidates. Interestingly, some of its members have been revealed as a valuable source of novel metabolites for medical and industrial purposes. Broad-range of potent bioactive compounds including antimicrobial, anticancer, and antipsychotic substances, broad-spectrum antibiotics and biocatalysts can be synthesized by the genus. In order to investigate biosynthetic pathways of the bioactive compounds and self-resistant mechanisms to these compounds, the links from genes to metabolites have yet been needed for further discovery and biotechnological development of the genus Nonomuraea.

  15. The genus Nonomuraea: A review of a rare actinomycete taxon for novel metabolites.

    PubMed

    Sungthong, Rungroch; Nakaew, Nareeluk

    2015-05-01

    The genus Nonomuraea is a rare actinomycete taxon with a long taxonomic history, while its generic description was recently emended. The genus is less known among the rare actinomycete genera as its taxonomic position was revised several times. It can be found in diverse ecological niches, while most of its member species were isolated from soil samples. However, new trends to discover the genus in other habitats are increasing. Generic abundance of the genus was found to be dependent on geographical changes. Novel sources together with selective and invented isolation techniques might increase a chance to explore the genus and its novel candidates. Interestingly, some of its members have been revealed as a valuable source of novel metabolites for medical and industrial purposes. Broad-range of potent bioactive compounds including antimicrobial, anticancer, and antipsychotic substances, broad-spectrum antibiotics and biocatalysts can be synthesized by the genus. In order to investigate biosynthetic pathways of the bioactive compounds and self-resistant mechanisms to these compounds, the links from genes to metabolites have yet been needed for further discovery and biotechnological development of the genus Nonomuraea. PMID:24633812

  16. The changing fates of the world's mammals

    PubMed Central

    Hoffmann, Michael; Belant, Jerrold L.; Chanson, Janice S.; Cox, Neil A.; Lamoreux, John; Rodrigues, Ana S. L.; Schipper, Jan; Stuart, Simon N.

    2011-01-01

    A recent complete assessment of the conservation status of 5487 mammal species demonstrated that at least one-fifth are at risk of extinction in the wild. We retrospectively identified genuine changes in extinction risk for mammals between 1996 and 2008 to calculate changes in the International Union for Conservation of Nature (IUCN) Red List Index (RLI). Species-level trends in the conservation status of mammalian diversity reveal that extinction risk in large-bodied species is increasing, and that the rate of deterioration has been most accelerated in the Indomalayan and Australasian realms. Expanding agriculture and hunting have been the main drivers of increased extinction risk in mammals. Site-based protection and management, legislation, and captive-breeding and reintroduction programmes have led to improvements in 24 species. We contextualize these changes, and explain why both deteriorations and improvements may be under-reported. Although this study highlights where conservation actions are leading to improvements, it fails to account for instances where conservation has prevented further deteriorations in the status of the world's mammals. The continued utility of the RLI is dependent on sustained investment to ensure repeated assessments of mammals over time and to facilitate future calculations of the RLI and measurement against global targets. PMID:21844039

  17. A Chinese triconodont mammal and mosaic evolution of the mammalian skeleton.

    PubMed

    Ji, Q; Luo, Z X; Ji, S A; Luo, Z

    1999-03-25

    Here we describe a new triconodont mammal from the Late Jurassic/Early Cretaceous period of Liaoning, China. This new mammal is represented by the best-preserved skeleton known so far for triconodonts which form one of the earliest Mesozoic mammalian groups with high diversity. The postcranial skeleton of this new triconodont shows a mosaic of characters, including a primitive pelvic girdle and hindlimb but a very derived pectoral girdle that is closely comparable to those of derived therians. Given the basal position of this taxon in mammalian phylogeny, its derived pectoral girdle indicates that homoplasies (similarities resulting from independent evolution among unrelated lineages) are as common in the postcranial skeleton as they are in the skull and dentition in the evolution of Mesozoic mammals. Limb structures of the new triconodont indicate that it was probably a ground-dwelling animal. PMID:10192332

  18. A Chinese triconodont mammal and mosaic evolution of the mammalian skeleton.

    PubMed

    Ji, Q; Luo, Z X; Ji, S A; Luo, Z

    1999-03-25

    Here we describe a new triconodont mammal from the Late Jurassic/Early Cretaceous period of Liaoning, China. This new mammal is represented by the best-preserved skeleton known so far for triconodonts which form one of the earliest Mesozoic mammalian groups with high diversity. The postcranial skeleton of this new triconodont shows a mosaic of characters, including a primitive pelvic girdle and hindlimb but a very derived pectoral girdle that is closely comparable to those of derived therians. Given the basal position of this taxon in mammalian phylogeny, its derived pectoral girdle indicates that homoplasies (similarities resulting from independent evolution among unrelated lineages) are as common in the postcranial skeleton as they are in the skull and dentition in the evolution of Mesozoic mammals. Limb structures of the new triconodont indicate that it was probably a ground-dwelling animal.

  19. Phylogenetic correlates of extinction risk in mammals: species in older lineages are not at greater risk.

    PubMed

    Verde Arregoitia, Luis Darcy; Blomberg, Simon P; Fisher, Diana O

    2013-08-22

    Phylogenetic information is becoming a recognized basis for evaluating conservation priorities, but associations between extinction risk and properties of a phylogeny such as diversification rates and phylogenetic lineage ages remain unclear. Limited taxon-specific analyses suggest that species in older lineages are at greater risk. We calculate quantitative properties of the mammalian phylogeny and model extinction risk as an ordinal index based on International Union for Conservation of Nature Red List categories. We test for associations between lineage age, clade size, evolutionary distinctiveness and extinction risk for 3308 species of terrestrial mammals. We show no significant global or regional associations, and three significant relationships within taxonomic groups. Extinction risk increases for evolutionarily distinctive primates and decreases with lineage age when lemurs are excluded. Lagomorph species (rabbits, hares and pikas) that have more close relatives are less threatened. We examine the relationship between net diversification rates and extinction risk for 173 genera and find no pattern. We conclude that despite being under-represented in the frequency distribution of lineage ages, species in older, slower evolving and distinct lineages are not more threatened or extinction-prone. Their extinction, however, would represent a disproportionate loss of unique evolutionary history.

  20. Inferring ancestral sequences in taxon-rich phylogenies.

    PubMed

    Gascuel, Olivier; Steel, Mike

    2010-10-01

    Statistical consistency in phylogenetics has traditionally referred to the accuracy of estimating phylogenetic parameters for a fixed number of species as we increase the number of characters. However, it is also useful to consider a dual type of statistical consistency where we increase the number of species, rather than characters. This raises some basic questions: what can we learn about the evolutionary process as we increase the number of species? In particular, does having more species allow us to infer the ancestral state of characters accurately? This question is particularly important when sequence evolution varies in a complex way from character to character, as methods applicable for i.i.d. models may no longer be valid. In this paper, we assemble a collection of results to analyse various approaches for inferring ancestral information with increasing accuracy as the number of taxa increases.

  1. Split-specific bootstrap measures for quantifying phylogenetic stability and the influence of taxon selection.

    PubMed

    Wang, Huai-Chun; Susko, Edward; Roger, Andrew J

    2016-12-01

    Assessing the robustness of an inferred phylogeny is an important element of phylogenetics. This is typically done with measures of stabilities at the internal branches and the variation of the positions of the leaf nodes. The bootstrap support for branches in maximum parsimony, distance and maximum likelihood estimation, or posterior probabilities in Bayesian inference, measure the uncertainty about a branch due to the sampling of the sites from genes or sampling genes from genomes. However, these measures do not reveal how taxon sampling affects branch support and the effects of taxon sampling on the estimated phylogeny. An internal branch in a phylogenetic tree can be viewed as a split that separates the taxa into two nonempty complementary subsets. We develop several split-specific measures of stability determined from bootstrap support for quartets. These include BPtaxon_split (average bootstrap percentage [BP] for all quartets involving a taxon within a split), BPsplit (BPtaxon_split averaged over taxa), BPtaxon (BPtaxon_split averaged over splits) and RBIC-taxon (average BP over all splits after removing a taxon). We also develop a pruned-tree distance metric. Application of our measures to empirical and simulated data illustrate that existing measures of overall stability can fail to detect taxa that are the primary source of a split-specific instability. Moreover, we show that the use of many reduced sets of quartets is important in being able to detect the influence of joint sets of taxa rather than individual taxa. These new measures are valuable diagnostic tools to guide taxon sampling in phylogenetic experimental design.

  2. The maximum rate of mammal evolution.

    PubMed

    Evans, Alistair R; Jones, David; Boyer, Alison G; Brown, James H; Costa, Daniel P; Ernest, S K Morgan; Fitzgerald, Erich M G; Fortelius, Mikael; Gittleman, John L; Hamilton, Marcus J; Harding, Larisa E; Lintulaakso, Kari; Lyons, S Kathleen; Okie, Jordan G; Saarinen, Juha J; Sibly, Richard M; Smith, Felisa A; Stephens, Patrick R; Theodor, Jessica M; Uhen, Mark D

    2012-03-13

    How fast can a mammal evolve from the size of a mouse to the size of an elephant? Achieving such a large transformation calls for major biological reorganization. Thus, the speed at which this occurs has important implications for extensive faunal changes, including adaptive radiations and recovery from mass extinctions. To quantify the pace of large-scale evolution we developed a metric, clade maximum rate, which represents the maximum evolutionary rate of a trait within a clade. We applied this metric to body mass evolution in mammals over the last 70 million years, during which multiple large evolutionary transitions occurred in oceans and on continents and islands. Our computations suggest that it took a minimum of 1.6, 5.1, and 10 million generations for terrestrial mammal mass to increase 100-, and 1,000-, and 5,000-fold, respectively. Values for whales were down to half the length (i.e., 1.1, 3, and 5 million generations), perhaps due to the reduced mechanical constraints of living in an aquatic environment. When differences in generation time are considered, we find an exponential increase in maximum mammal body mass during the 35 million years following the Cretaceous-Paleogene (K-Pg) extinction event. Our results also indicate a basic asymmetry in macroevolution: very large decreases (such as extreme insular dwarfism) can happen at more than 10 times the rate of increases. Our findings allow more rigorous comparisons of microevolutionary and macroevolutionary patterns and processes.

  3. The maximum rate of mammal evolution

    NASA Astrophysics Data System (ADS)

    Evans, Alistair R.; Jones, David; Boyer, Alison G.; Brown, James H.; Costa, Daniel P.; Ernest, S. K. Morgan; Fitzgerald, Erich M. G.; Fortelius, Mikael; Gittleman, John L.; Hamilton, Marcus J.; Harding, Larisa E.; Lintulaakso, Kari; Lyons, S. Kathleen; Okie, Jordan G.; Saarinen, Juha J.; Sibly, Richard M.; Smith, Felisa A.; Stephens, Patrick R.; Theodor, Jessica M.; Uhen, Mark D.

    2012-03-01

    How fast can a mammal evolve from the size of a mouse to the size of an elephant? Achieving such a large transformation calls for major biological reorganization. Thus, the speed at which this occurs has important implications for extensive faunal changes, including adaptive radiations and recovery from mass extinctions. To quantify the pace of large-scale evolution we developed a metric, clade maximum rate, which represents the maximum evolutionary rate of a trait within a clade. We applied this metric to body mass evolution in mammals over the last 70 million years, during which multiple large evolutionary transitions occurred in oceans and on continents and islands. Our computations suggest that it took a minimum of 1.6, 5.1, and 10 million generations for terrestrial mammal mass to increase 100-, and 1,000-, and 5,000-fold, respectively. Values for whales were down to half the length (i.e., 1.1, 3, and 5 million generations), perhaps due to the reduced mechanical constraints of living in an aquatic environment. When differences in generation time are considered, we find an exponential increase in maximum mammal body mass during the 35 million years following the Cretaceous-Paleogene (K-Pg) extinction event. Our results also indicate a basic asymmetry in macroevolution: very large decreases (such as extreme insular dwarfism) can happen at more than 10 times the rate of increases. Our findings allow more rigorous comparisons of microevolutionary and macroevolutionary patterns and processes.

  4. The maximum rate of mammal evolution.

    PubMed

    Evans, Alistair R; Jones, David; Boyer, Alison G; Brown, James H; Costa, Daniel P; Ernest, S K Morgan; Fitzgerald, Erich M G; Fortelius, Mikael; Gittleman, John L; Hamilton, Marcus J; Harding, Larisa E; Lintulaakso, Kari; Lyons, S Kathleen; Okie, Jordan G; Saarinen, Juha J; Sibly, Richard M; Smith, Felisa A; Stephens, Patrick R; Theodor, Jessica M; Uhen, Mark D

    2012-03-13

    How fast can a mammal evolve from the size of a mouse to the size of an elephant? Achieving such a large transformation calls for major biological reorganization. Thus, the speed at which this occurs has important implications for extensive faunal changes, including adaptive radiations and recovery from mass extinctions. To quantify the pace of large-scale evolution we developed a metric, clade maximum rate, which represents the maximum evolutionary rate of a trait within a clade. We applied this metric to body mass evolution in mammals over the last 70 million years, during which multiple large evolutionary transitions occurred in oceans and on continents and islands. Our computations suggest that it took a minimum of 1.6, 5.1, and 10 million generations for terrestrial mammal mass to increase 100-, and 1,000-, and 5,000-fold, respectively. Values for whales were down to half the length (i.e., 1.1, 3, and 5 million generations), perhaps due to the reduced mechanical constraints of living in an aquatic environment. When differences in generation time are considered, we find an exponential increase in maximum mammal body mass during the 35 million years following the Cretaceous-Paleogene (K-Pg) extinction event. Our results also indicate a basic asymmetry in macroevolution: very large decreases (such as extreme insular dwarfism) can happen at more than 10 times the rate of increases. Our findings allow more rigorous comparisons of microevolutionary and macroevolutionary patterns and processes. PMID:22308461

  5. The maximum rate of mammal evolution

    PubMed Central

    Evans, Alistair R.; Jones, David; Boyer, Alison G.; Brown, James H.; Costa, Daniel P.; Ernest, S. K. Morgan; Fitzgerald, Erich M. G.; Fortelius, Mikael; Gittleman, John L.; Hamilton, Marcus J.; Harding, Larisa E.; Lintulaakso, Kari; Lyons, S. Kathleen; Okie, Jordan G.; Saarinen, Juha J.; Sibly, Richard M.; Smith, Felisa A.; Stephens, Patrick R.; Theodor, Jessica M.; Uhen, Mark D.

    2012-01-01

    How fast can a mammal evolve from the size of a mouse to the size of an elephant? Achieving such a large transformation calls for major biological reorganization. Thus, the speed at which this occurs has important implications for extensive faunal changes, including adaptive radiations and recovery from mass extinctions. To quantify the pace of large-scale evolution we developed a metric, clade maximum rate, which represents the maximum evolutionary rate of a trait within a clade. We applied this metric to body mass evolution in mammals over the last 70 million years, during which multiple large evolutionary transitions occurred in oceans and on continents and islands. Our computations suggest that it took a minimum of 1.6, 5.1, and 10 million generations for terrestrial mammal mass to increase 100-, and 1,000-, and 5,000-fold, respectively. Values for whales were down to half the length (i.e., 1.1, 3, and 5 million generations), perhaps due to the reduced mechanical constraints of living in an aquatic environment. When differences in generation time are considered, we find an exponential increase in maximum mammal body mass during the 35 million years following the Cretaceous–Paleogene (K–Pg) extinction event. Our results also indicate a basic asymmetry in macroevolution: very large decreases (such as extreme insular dwarfism) can happen at more than 10 times the rate of increases. Our findings allow more rigorous comparisons of microevolutionary and macroevolutionary patterns and processes. PMID:22308461

  6. The evolution of mammal body sizes: responses to Cenozoic climate change in North American mammals.

    PubMed

    Lovegrove, B G; Mowoe, M O

    2013-06-01

    Explanations for the evolution of body size in mammals have remained surprisingly elusive despite the central importance of body size in evolutionary biology. Here, we present a model which argues that the body sizes of Nearctic mammals were moulded by Cenozoic climate and vegetation changes. Following the early Eocene Climate Optimum, forests retreated and gave way to open woodland and savannah landscapes, followed later by grasslands. Many herbivores that radiated in these new landscapes underwent a switch from browsing to grazing associated with increased unguligrade cursoriality and body size, the latter driven by the energetics and constraints of cellulose digestion (fermentation). Carnivores also increased in size and digitigrade, cursorial capacity to occupy a size distribution allowing the capture of prey of the widest range of body sizes. With the emergence of larger, faster carnivores, plantigrade mammals were constrained from evolving to large body sizes and most remained smaller than 1 kg throughout the middle Cenozoic. We find no consistent support for either Cope's Rule or Bergmann's Rule in plantigrade mammals, the largest locomotor guild (n = 1186, 59% of species in the database). Some cold-specialist plantigrade mammals, such as beavers and marmots, showed dramatic increases in body mass following the Miocene Climate Optimum which may, however, be partially explained by Bergmann's rule. This study reemphasizes the necessity of considering the evolutionary history and resultant form and function of mammalian morphotypes when attempting to understand contemporary mammalian body size distributions.

  7. Psychopathy as a Taxon: Evidence That Psychopaths Are a Discrete Class.

    ERIC Educational Resources Information Center

    Harris, Grant T.; And Others

    1994-01-01

    Applied taxometric analyses to construct of psychopathy (as measured by Psychopathy Checklist) and to several variables reflecting antisocial childhood, adult criminality, and criminal recidivism. Findings from 653 serious offenders assessed or treated in maximum-security institution supported existence of taxon underlying psychopathy. Childhood…

  8. New Nocardia taxon among isolates of Nocardia brasiliensis associated with invasive disease.

    PubMed Central

    Wallace, R J; Brown, B A; Blacklock, Z; Ulrich, R; Jost, K; Brown, J M; McNeil, M M; Onyi, G; Steingrube, V A; Gibson, J

    1995-01-01

    Nocardia brasiliensis, the second most frequently isolated aerobic actinomycete in the clinical laboratory, is usually associated with localized cutaneous infections. However, 22% of 238 N. brasiliensis isolates from the United States and 12% of 66 isolates from Queensland, Australia, which had been collected over a 17-year period, were associated with extracutaneous and/or disseminated diseases. Of the 62 invasive isolates, 37 (60%) were susceptible to ciprofloxacin and/or were susceptible to clarithromycin and resistant to minocycline, compared with only 6 (3%) of 242 localized cutaneous isolates. The 43 isolates with this susceptibility pattern appeared to define a new taxon. They were similar to Nocardia asteroides complex isolates clinically in proportions from persons with pulmonary (70%), central nervous system (23%), and/or disseminated diseases (37%) in the setting of corticosteroids (74%) or AIDS (14%). This putative new taxon differed from N. brasiliensis in the hydrolysis of adenine (92 versus 4%), beta-lactamase patterns on isoelectric focusing, and the presence of two early mycolic acid-ester peaks by high-performance liquid chromatography. Restriction analysis of a 439-bp fragment of the 65-kDa heat shock protein gene revealed that N. brasiliensis and the new taxon had different restriction patterns with 8 of the 11 enzymes tested. Screening of invasive isolates of N. brasiliensis for susceptibility to ciprofloxacin will identify most isolates of the new taxon, which likely represents a new Nocardia species. PMID:7650180

  9. 7 CFR 360.501 - Petitions to remove a taxon from the noxious weed lists.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Petitions to remove a taxon from the noxious weed lists. 360.501 Section 360.501 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS §...

  10. 7 CFR 360.501 - Petitions to remove a taxon from the noxious weed lists.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Petitions to remove a taxon from the noxious weed lists. 360.501 Section 360.501 Agriculture Regulations of the Department of Agriculture (Continued) ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE NOXIOUS WEED REGULATIONS §...

  11. SUMAC: Constructing Phylogenetic Supermatrices and Assessing Partially Decisive Taxon Coverage.

    PubMed

    Freyman, William A

    2015-01-01

    The amount of phylogenetically informative sequence data in GenBank is growing at an exponential rate, and large phylogenetic trees are increasingly used in research. Tools are needed to construct phylogenetic sequence matrices from GenBank data and evaluate the effect of missing data. Supermatrix Constructor (SUMAC) is a tool to data-mine GenBank, construct phylogenetic supermatrices, and assess the phylogenetic decisiveness of a matrix given the pattern of missing sequence data. SUMAC calculates a novel metric, Missing Sequence Decisiveness Scores (MSDS), which measures how much each individual missing sequence contributes to the decisiveness of the matrix. MSDS can be used to compare supermatrices and prioritize the acquisition of new sequence data. SUMAC constructs supermatrices either through an exploratory clustering of all GenBank sequences within a taxonomic group or by using guide sequences to build homologous clusters in a more targeted manner. SUMAC assembles supermatrices for any taxonomic group recognized in GenBank and is optimized to run on multicore computer systems by parallelizing multiple stages of operation. SUMAC is implemented as a Python package that can run as a stand-alone command-line program, or its modules and objects can be incorporated within other programs. SUMAC is released under the open source GPLv3 license and is available at https://github.com/wf8/sumac. PMID:26648681

  12. Assessing Phylogenetic Relationships among Galliformes: A Multigene Phylogeny with Expanded Taxon Sampling in Phasianidae

    PubMed Central

    Wang, Ning; Kimball, Rebecca T.; Braun, Edward L.; Liang, Bin; Zhang, Zhengwang

    2013-01-01

    Galliform birds (relatives of the chicken and turkey) have attracted substantial attention due to their importance to society and value as model systems. This makes understanding the evolutionary history of Galliformes, especially the species-rich family Phasianidae, particularly interesting and important for comparative studies in this group. Previous studies have differed in their conclusions regarding galliform phylogeny. Some of these studies have suggested that specific clades within this order underwent rapid radiations, potentially leading to the observed difficulty in resolving their phylogenetic relationships. Here we presented analyses of six nuclear intron sequences and two mitochondrial regions, an amount of sequence data larger than many previous studies, and expanded taxon sampling by collecting data from 88 galliform species and four anseriform outgroups. Our results corroborated recent studies describing relationships among the major families, and provided further evidence that the traditional division of the largest family, the Phasianidae into two major groups (“pheasants” and “partridges”) is not valid. Within the Phasianidae, relationships among many genera have varied among studies and there has been little consensus for the placement of many taxa. Using this large dataset, with substantial sampling within the Phasianidae, we obtained strong bootstrap support to confirm some previously hypothesized relationships and we were able to exclude others. In addition, we added the first nuclear sequence data for the partridge and quail genera Ammoperdix, Caloperdix, Excalfactoria, and Margaroperdix, placing these taxa in the galliform tree of life with confidence. Despite the novel insights obtained by combining increased sampling of taxa and loci, our results suggest that additional data collection will be necessary to solve the remaining uncertainties. PMID:23741315

  13. Assessing phylogenetic relationships among galliformes: a multigene phylogeny with expanded taxon sampling in Phasianidae.

    PubMed

    Wang, Ning; Kimball, Rebecca T; Braun, Edward L; Liang, Bin; Zhang, Zhengwang

    2013-01-01

    Galliform birds (relatives of the chicken and turkey) have attracted substantial attention due to their importance to society and value as model systems. This makes understanding the evolutionary history of Galliformes, especially the species-rich family Phasianidae, particularly interesting and important for comparative studies in this group. Previous studies have differed in their conclusions regarding galliform phylogeny. Some of these studies have suggested that specific clades within this order underwent rapid radiations, potentially leading to the observed difficulty in resolving their phylogenetic relationships. Here we presented analyses of six nuclear intron sequences and two mitochondrial regions, an amount of sequence data larger than many previous studies, and expanded taxon sampling by collecting data from 88 galliform species and four anseriform outgroups. Our results corroborated recent studies describing relationships among the major families, and provided further evidence that the traditional division of the largest family, the Phasianidae into two major groups ("pheasants" and "partridges") is not valid. Within the Phasianidae, relationships among many genera have varied among studies and there has been little consensus for the placement of many taxa. Using this large dataset, with substantial sampling within the Phasianidae, we obtained strong bootstrap support to confirm some previously hypothesized relationships and we were able to exclude others. In addition, we added the first nuclear sequence data for the partridge and quail genera Ammoperdix, Caloperdix, Excalfactoria, and Margaroperdix, placing these taxa in the galliform tree of life with confidence. Despite the novel insights obtained by combining increased sampling of taxa and loci, our results suggest that additional data collection will be necessary to solve the remaining uncertainties.

  14. Communication masking in marine mammals: A review and research strategy.

    PubMed

    Erbe, Christine; Reichmuth, Colleen; Cunningham, Kane; Lucke, Klaus; Dooling, Robert

    2016-02-15

    Underwater noise, whether of natural or anthropogenic origin, has the ability to interfere with the way in which marine mammals receive acoustic signals (i.e., for communication, social interaction, foraging, navigation, etc.). This phenomenon, termed auditory masking, has been well studied in humans and terrestrial vertebrates (in particular birds), but less so in marine mammals. Anthropogenic underwater noise seems to be increasing in parts of the world's oceans and concerns about associated bioacoustic effects, including masking, are growing. In this article, we review our understanding of masking in marine mammals, summarise data on marine mammal hearing as they relate to masking (including audiograms, critical ratios, critical bandwidths, and auditory integration times), discuss masking release processes of receivers (including comodulation masking release and spatial release from masking) and anti-masking strategies of signalers (e.g. Lombard effect), and set a research framework for improved assessment of potential masking in marine mammals.

  15. DNA barcoding in mammals.

    PubMed

    Ivanova, Natalia V; Clare, Elizabeth L; Borisenko, Alex V

    2012-01-01

    DNA barcoding provides an operational framework for mammalian taxonomic identification and cryptic species discovery. Focused effort to build a reference library of genetic data has resulted in the assembly of over 35 K mammalian cytochrome c oxidase subunit I sequences and outlined the scope of mammal-related barcoding projects. Based on the above experience, this chapter recounts three typical methodological pathways involved in mammalian barcoding: routine methods aimed at assembling the reference sequence library from high quality samples, express approaches used to attain cheap and fast taxonomic identifications for applied purposes, and forensic techniques employed when dealing with degraded material. Most of the methods described are applicable to a range of vertebrate taxa outside Mammalia.

  16. 75 FR 77616 - Marine Mammals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-13

    ... endangered and threatened species (50 CFR parts 222-226). Permit No. 14334, issued on August 17, 2009 (74 FR... National Oceanic and Atmospheric Administration RIN 0648-XP18 Marine Mammals AGENCY: National Marine... Marine Mammal Protection Act of 1972, as amended (16 U.S.C. 1361 et seq.), the regulations governing...

  17. 76 FR 72681 - Marine Mammals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-25

    ... (75 FR 27300), authorizes the permit holder to take ribbon seals (Phoca fasciata), spotted seals (P... National Oceanic and Atmospheric Administration RIN 0648-XU87 Marine Mammals AGENCY: National Marine... Mammal Laboratory, (Responsible Party: Dr. John Bengtson, Director), Seattle, WA, has applied for...

  18. Species Richness Responses to Structural or Compositional Habitat Diversity between and within Grassland Patches: A Multi-Taxon Approach

    PubMed Central

    Lengyel, Szabolcs; Déri, Eszter; Magura, Tibor

    2016-01-01

    Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD) is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR) of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary) and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals) showed that the wet-dry gradient (compositional HD at the between-patch scale) was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale) was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale) was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none) was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve biodiversity in

  19. Species Richness Responses to Structural or Compositional Habitat Diversity between and within Grassland Patches: A Multi-Taxon Approach.

    PubMed

    Lengyel, Szabolcs; Déri, Eszter; Magura, Tibor

    2016-01-01

    Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD) is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR) of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary) and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals) showed that the wet-dry gradient (compositional HD at the between-patch scale) was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale) was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale) was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none) was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve biodiversity in

  20. Species Richness Responses to Structural or Compositional Habitat Diversity between and within Grassland Patches: A Multi-Taxon Approach.

    PubMed

    Lengyel, Szabolcs; Déri, Eszter; Magura, Tibor

    2016-01-01

    Habitat diversity (spatial heterogeneity within and between habitat patches in a landscape, HD) is often invoked as a driver of species diversity at small spatial scales. However, the effect of HD on species richness (SR) of multiple taxa is not well understood. We quantified HD and SR in a wet-dry gradient of open grassland habitats in Hortobágy National Park (E-Hungary) and tested the effect of compositional and structural factors of HD on SR of flowering plants, orthopterans, true bugs, spiders, ground beetles and birds. Our dataset on 434 grassland species (170 plants, 264 animals) showed that the wet-dry gradient (compositional HD at the between-patch scale) was primarily related to SR in orthopterans, ground-dwelling arthropods, and all animals combined. The patchiness, or plant association richness, of the vegetation (compositional HD at the within-patch scale) was related to SR of vegetation-dwelling arthropods, whereas vegetation height (structural HD at the within-patch scale) was related to SR of ground-dwelling arthropods and birds. Patch area was related to SR only in birds, whereas management (grazing, mowing, none) was related to SR of plants and true bugs. All relationships between HD and SR were positive, indicating increasing SR with increasing HD. However, total SR was not related to HD because different taxa showed similar positive responses to different HD variables. Our findings, therefore, show that even though HD positively influences SR in a wide range of grassland taxa, each taxon responds to different compositional or structural measures of HD, resulting in the lack of a consistent relationship between HD and SR when taxon responses are pooled. The idiosyncratic responses shown here exemplify the difficulties in detecting general HD-SR relationships over multiple taxa. Our results also suggest that management and restoration aimed specifically to sustain or increase the diversity of habitats are required to conserve biodiversity in

  1. Protection of mammal diversity in Central America

    USGS Publications Warehouse

    Jenkins, Clinton N.; Giri, Chandra

    2008-01-01

    Central America is exceptionally rich in biodiversity, but varies widely in the attention its countries devote to conservation. Protected areas, widely considered the cornerstone of conservation, were not always created with the intent of conserving that biodiversity. We assessed how well the protected-area system of Central America includes the region's mammal diversity. This first required a refinement of existing range maps to reduce their extensive errors of commission (i.e., predicted presences in places where species do not occur). For this refinement, we used the ecological limits of each species to identify and remove unsuitable areas from the range. We then compared these maps with the locations of protected areas to measure the habitat protected for each of the region's 250 endemic mammals. The species most vulnerable to extinction—those with small ranges—were largely outside protected areas. Nevertheless, the most strictly protected areas tended toward areas with many small-ranged species. To improve the protection coverage of mammal diversity in the region, we identified a set of priority sites that would best complement the existing protected areas. Protecting these new sites would require a relatively small increase in the total area protected, but could greatly enhance mammal conservation.

  2. A new eutriconodont mammal and evolutionary development in early mammals.

    PubMed

    Luo, Zhe-Xi; Chen, Peiji; Li, Gang; Chen, Meng

    2007-03-15

    Detachment of the three tiny middle ear bones from the reptilian mandible is an important innovation of modern mammals. Here we describe a Mesozoic eutriconodont nested within crown mammals that clearly illustrates this transition: the middle ear bones are connected to the mandible via an ossified Meckel's cartilage. The connected ear and jaw structure is similar to the embryonic pattern in modern monotremes (egg-laying mammals) and placental mammals, but is a paedomorphic feature retained in the adult, unlike in monotreme and placental adults. This suggests that reversal to (or retention of) this premammalian ancestral condition is correlated with different developmental timing (heterochrony) in eutriconodonts. This new eutriconodont adds to the evidence of homoplasy of vertebral characters in the thoraco-lumbar transition and unfused lumbar ribs among early mammals. This is similar to the effect of homeobox gene patterning of vertebrae in modern mammals, making it plausible to extrapolate the effects of Hox gene patterning to account for homoplastic evolution of vertebral characters in early mammals.

  3. Climate and species richness predict the phylogenetic structure of African mammal communities.

    PubMed

    Kamilar, Jason M; Beaudrot, Lydia; Reed, Kaye E

    2015-01-01

    We have little knowledge of how climatic variation (and by proxy, habitat variation) influences the phylogenetic structure of tropical communities. Here, we quantified the phylogenetic structure of mammal communities in Africa to investigate how community structure varies with respect to climate and species richness variation across the continent. In addition, we investigated how phylogenetic patterns vary across carnivores, primates, and ungulates. We predicted that climate would differentially affect the structure of communities from different clades due to between-clade biological variation. We examined 203 communities using two metrics, the net relatedness (NRI) and nearest taxon (NTI) indices. We used simultaneous autoregressive models to predict community phylogenetic structure from climate variables and species richness. We found that most individual communities exhibited a phylogenetic structure consistent with a null model, but both climate and species richness significantly predicted variation in community phylogenetic metrics. Using NTI, species rich communities were composed of more distantly related taxa for all mammal communities, as well as for communities of carnivorans or ungulates. Temperature seasonality predicted the phylogenetic structure of mammal, carnivoran, and ungulate communities, and annual rainfall predicted primate community structure. Additional climate variables related to temperature and rainfall also predicted the phylogenetic structure of ungulate communities. We suggest that both past interspecific competition and habitat filtering have shaped variation in tropical mammal communities. The significant effect of climatic factors on community structure has important implications for the diversity of mammal communities given current models of future climate change.

  4. Climate and Species Richness Predict the Phylogenetic Structure of African Mammal Communities

    PubMed Central

    Kamilar, Jason M.; Beaudrot, Lydia; Reed, Kaye E.

    2015-01-01

    We have little knowledge of how climatic variation (and by proxy, habitat variation) influences the phylogenetic structure of tropical communities. Here, we quantified the phylogenetic structure of mammal communities in Africa to investigate how community structure varies with respect to climate and species richness variation across the continent. In addition, we investigated how phylogenetic patterns vary across carnivores, primates, and ungulates. We predicted that climate would differentially affect the structure of communities from different clades due to between-clade biological variation. We examined 203 communities using two metrics, the net relatedness (NRI) and nearest taxon (NTI) indices. We used simultaneous autoregressive models to predict community phylogenetic structure from climate variables and species richness. We found that most individual communities exhibited a phylogenetic structure consistent with a null model, but both climate and species richness significantly predicted variation in community phylogenetic metrics. Using NTI, species rich communities were composed of more distantly related taxa for all mammal communities, as well as for communities of carnivorans or ungulates. Temperature seasonality predicted the phylogenetic structure of mammal, carnivoran, and ungulate communities, and annual rainfall predicted primate community structure. Additional climate variables related to temperature and rainfall also predicted the phylogenetic structure of ungulate communities. We suggest that both past interspecific competition and habitat filtering have shaped variation in tropical mammal communities. The significant effect of climatic factors on community structure has important implications for the diversity of mammal communities given current models of future climate change. PMID:25875361

  5. Marine mammal harvests and other interactions with humans.

    PubMed

    Hovelsrud, Grete K; McKenna, Meghan; Huntington, Henry P

    2008-03-01

    The Arctic is currently undergoing rapid social and environmental changes, and while the peoples of the north have a long history of adapting, the current changes in climate pose unprecedented challenges to the marine mammal-human interactions in the Arctic regions. Arctic marine mammals have been and remain an important resource for many of the indigenous and nonindigenous people of the north. Changes in climate are likely to bring about profound changes to the environment in which these animals live and subsequently to the hunting practices and livelihoods of the people who hunt them. Climate change will lead to reduction in the sea ice extent and thickness and will likely increase shipping through the Northern Sea Route and the Northwest Passage and oil and gas activities in Arctic areas previously inaccessible. Such activities will lead to more frequent interactions between humans and marine mammals. These activities may also change the distribution of marine mammals, affecting the hunters. This paper has three parts. First, an overview of marine mammal harvesting activities in the different circumpolar regions provides a snapshot of current practices and conditions. Second, case studies of selected Arctic regions, indigenous groups, and species provide insight into the manner in which climate change is already impacting marine mammal harvesting activities in the Arctic. Third, we describe how climate change is likely to affect shipping and oil and gas exploration and production activities in the Arctic and describe the possible implications of these changes for the marine mammal populations. We conclude that many of the consequences of climate change are likely to be negative for marine mammal hunters and for marine mammals. Lack of adequate baseline data, however, makes it difficult to identify specific causal mechanisms and thus to develop appropriate conservation measures. Nonetheless, the future of Arctic marine mammals and human uses of them depends on

  6. Marine mammal harvests and other interactions with humans.

    PubMed

    Hovelsrud, Grete K; McKenna, Meghan; Huntington, Henry P

    2008-03-01

    The Arctic is currently undergoing rapid social and environmental changes, and while the peoples of the north have a long history of adapting, the current changes in climate pose unprecedented challenges to the marine mammal-human interactions in the Arctic regions. Arctic marine mammals have been and remain an important resource for many of the indigenous and nonindigenous people of the north. Changes in climate are likely to bring about profound changes to the environment in which these animals live and subsequently to the hunting practices and livelihoods of the people who hunt them. Climate change will lead to reduction in the sea ice extent and thickness and will likely increase shipping through the Northern Sea Route and the Northwest Passage and oil and gas activities in Arctic areas previously inaccessible. Such activities will lead to more frequent interactions between humans and marine mammals. These activities may also change the distribution of marine mammals, affecting the hunters. This paper has three parts. First, an overview of marine mammal harvesting activities in the different circumpolar regions provides a snapshot of current practices and conditions. Second, case studies of selected Arctic regions, indigenous groups, and species provide insight into the manner in which climate change is already impacting marine mammal harvesting activities in the Arctic. Third, we describe how climate change is likely to affect shipping and oil and gas exploration and production activities in the Arctic and describe the possible implications of these changes for the marine mammal populations. We conclude that many of the consequences of climate change are likely to be negative for marine mammal hunters and for marine mammals. Lack of adequate baseline data, however, makes it difficult to identify specific causal mechanisms and thus to develop appropriate conservation measures. Nonetheless, the future of Arctic marine mammals and human uses of them depends on

  7. Comparative genomics of Bifidobacterium animalis subsp. lactis reveals a strict monophyletic bifidobacterial taxon.

    PubMed

    Milani, Christian; Duranti, Sabrina; Lugli, Gabriele Andrea; Bottacini, Francesca; Strati, Francesco; Arioli, Stefania; Foroni, Elena; Turroni, Francesca; van Sinderen, Douwe; Ventura, Marco

    2013-07-01

    Strains of Bifidobacterium animalis subsp. lactis are extensively exploited by the food industry as health-promoting bacteria, although the genetic variability of members belonging to this taxon has so far not received much scientific attention. In this article, we describe the complete genetic makeup of the B. animalis subsp. lactis Bl12 genome and discuss the genetic relatedness of this strain with other sequenced strains belonging to this taxon. Moreover, a detailed comparative genomic analysis of B. animalis subsp. lactis genomes was performed, which revealed a closely related and isogenic nature of all currently available B. animalis subsp. lactis strains, thus strongly suggesting a closed pan-genome structure of this bacterial group. PMID:23645200

  8. Comparative review of marine mammal guidance implemented during naval exercises.

    PubMed

    Dolman, Sarah J; Weir, Caroline R; Jasny, Michael

    2009-04-01

    This article reviews the types and effectiveness of marine mammal mitigation measures used during some naval activities worldwide. The three main standard methods used to mitigate the potential impacts of naval sonar sound on marine mammals are (1) time/area planning (of exercises/active sonar use) to avoid marine mammals; (2) implementation of operational procedures (e.g. 'soft start' - where sound levels are gradually increased over time); and (3) monitoring of animals for the purpose of maintaining an 'exclusion zone' around the sound source. Suggestions towards a minimum worldwide mitigation standard are made.

  9. Merging ancient and modern DNA: extinct seabird taxon rediscovered in the North Tasman Sea.

    PubMed

    Steeves, Tammy E; Holdaway, Richard N; Hale, Marie L; McLay, Emma; McAllan, Ian A W; Christian, Margaret; Hauber, Mark E; Bunce, Michael

    2010-02-23

    Ancient DNA has revolutionized the way in which evolutionary biologists research both extinct and extant taxa, from the inference of evolutionary history to the resolution of taxonomy. Here, we present, to our knowledge, the first study to report the rediscovery of an 'extinct' avian taxon, the Tasman booby (Sula tasmani), using classical palaeontological data combined with ancient and modern DNA data. Contrary to earlier work, we show an overlap in size between fossil and modern birds in the North Tasman Sea (classified currently as S. tasmani and Sula dactylatra fullagari, respectively). In addition, we show that Holocene fossil birds have mitochondrial control region sequences that are identical to those found in modern birds. These results indicate that the Tasman booby is not an extinct taxon: S. dactylatra fullagari O'Brien & Davies, 1990 is therefore a junior synonym of Sula tasmani van Tets, Meredith, Fullagar & Davidson, 1988 and all North Tasman Sea boobies should be known as S. d. tasmani. In addition to reporting the rediscovery of an extinct avian taxon, our study highlights the need for researchers to be cognizant of multidisciplinary approaches to understanding taxonomy and past biodiversity.

  10. Evidence of taxon cycles in an Indo-Pacific passerine bird radiation (Aves: Pachycephala)

    PubMed Central

    Jønsson, Knud Andreas; Irestedt, Martin; Christidis, Les; Clegg, Sonya M.; Holt, Ben G.; Fjeldså, Jon

    2014-01-01

    Many insular taxa possess extraordinary abilities to disperse but may differ in their abilities to diversify and compete. While some taxa are widespread across archipelagos, others have disjunct (relictual) populations. These types of taxa, exemplified in the literature by selections of unrelated taxa, have been interpreted as representing a continuum of expansions and contractions (i.e. taxon cycles). Here, we use molecular data of 35 out of 40 species of the avian genus Pachycephala (including 54 out of 66 taxa in Pachycephala pectoralis (sensu lato), to assess the spatio-temporal evolution of the group. We also include data on species distributions, morphology, habitat and elevational ranges to test a number of predictions associated with the taxon-cycle hypothesis. We demonstrate that relictual species persist on the largest and highest islands across the Indo-Pacific, whereas recent archipelago expansions resulted in colonization of all islands in a region. For co-occurring island taxa, the earliest colonists generally inhabit the interior and highest parts of an island, with little spatial overlap with later colonists. Collectively, our data support the idea that taxa continuously pass through phases of expansions and contractions (i.e. taxon cycles). PMID:24403319

  11. Merging ancient and modern DNA: extinct seabird taxon rediscovered in the North Tasman Sea.

    PubMed

    Steeves, Tammy E; Holdaway, Richard N; Hale, Marie L; McLay, Emma; McAllan, Ian A W; Christian, Margaret; Hauber, Mark E; Bunce, Michael

    2010-02-23

    Ancient DNA has revolutionized the way in which evolutionary biologists research both extinct and extant taxa, from the inference of evolutionary history to the resolution of taxonomy. Here, we present, to our knowledge, the first study to report the rediscovery of an 'extinct' avian taxon, the Tasman booby (Sula tasmani), using classical palaeontological data combined with ancient and modern DNA data. Contrary to earlier work, we show an overlap in size between fossil and modern birds in the North Tasman Sea (classified currently as S. tasmani and Sula dactylatra fullagari, respectively). In addition, we show that Holocene fossil birds have mitochondrial control region sequences that are identical to those found in modern birds. These results indicate that the Tasman booby is not an extinct taxon: S. dactylatra fullagari O'Brien & Davies, 1990 is therefore a junior synonym of Sula tasmani van Tets, Meredith, Fullagar & Davidson, 1988 and all North Tasman Sea boobies should be known as S. d. tasmani. In addition to reporting the rediscovery of an extinct avian taxon, our study highlights the need for researchers to be cognizant of multidisciplinary approaches to understanding taxonomy and past biodiversity. PMID:19675005

  12. Invasive mammal eradication on islands results in substantial conservation gains.

    PubMed

    Jones, Holly P; Holmes, Nick D; Butchart, Stuart H M; Tershy, Bernie R; Kappes, Peter J; Corkery, Ilse; Aguirre-Muñoz, Alfonso; Armstrong, Doug P; Bonnaud, Elsa; Burbidge, Andrew A; Campbell, Karl; Courchamp, Franck; Cowan, Philip E; Cuthbert, Richard J; Ebbert, Steve; Genovesi, Piero; Howald, Gregg R; Keitt, Bradford S; Kress, Stephen W; Miskelly, Colin M; Oppel, Steffen; Poncet, Sally; Rauzon, Mark J; Rocamora, Gérard; Russell, James C; Samaniego-Herrera, Araceli; Seddon, Philip J; Spatz, Dena R; Towns, David R; Croll, Donald A

    2016-04-12

    More than US$21 billion is spent annually on biodiversity conservation. Despite their importance for preventing or slowing extinctions and preserving biodiversity, conservation interventions are rarely assessed systematically for their global impact. Islands house a disproportionately higher amount of biodiversity compared with mainlands, much of which is highly threatened with extinction. Indeed, island species make up nearly two-thirds of recent extinctions. Islands therefore are critical targets of conservation. We used an extensive literature and database review paired with expert interviews to estimate the global benefits of an increasingly used conservation action to stem biodiversity loss: eradication of invasive mammals on islands. We found 236 native terrestrial insular faunal species (596 populations) that benefitted through positive demographic and/or distributional responses from 251 eradications of invasive mammals on 181 islands. Seven native species (eight populations) were negatively impacted by invasive mammal eradication. Four threatened species had their International Union for the Conservation of Nature (IUCN) Red List extinction-risk categories reduced as a direct result of invasive mammal eradication, and no species moved to a higher extinction-risk category. We predict that 107 highly threatened birds, mammals, and reptiles on the IUCN Red List-6% of all these highly threatened species-likely have benefitted from invasive mammal eradications on islands. Because monitoring of eradication outcomes is sporadic and limited, the impacts of global eradications are likely greater than we report here. Our results highlight the importance of invasive mammal eradication on islands for protecting the world's most imperiled fauna. PMID:27001852

  13. Invasive mammal eradication on islands results in substantial conservation gains

    PubMed Central

    Jones, Holly P.; Holmes, Nick D.; Butchart, Stuart H. M.; Tershy, Bernie R.; Kappes, Peter J.; Corkery, Ilse; Aguirre-Muñoz, Alfonso; Armstrong, Doug P.; Bonnaud, Elsa; Burbidge, Andrew A.; Campbell, Karl; Courchamp, Franck; Cowan, Philip E.; Cuthbert, Richard J.; Ebbert, Steve; Genovesi, Piero; Howald, Gregg R.; Keitt, Bradford S.; Kress, Stephen W.; Miskelly, Colin M.; Oppel, Steffen; Poncet, Sally; Rauzon, Mark J.; Rocamora, Gérard; Russell, James C.; Samaniego-Herrera, Araceli; Seddon, Philip J.; Spatz, Dena R.; Towns, David R.; Croll, Donald A.

    2016-01-01

    More than US$21 billion is spent annually on biodiversity conservation. Despite their importance for preventing or slowing extinctions and preserving biodiversity, conservation interventions are rarely assessed systematically for their global impact. Islands house a disproportionately higher amount of biodiversity compared with mainlands, much of which is highly threatened with extinction. Indeed, island species make up nearly two-thirds of recent extinctions. Islands therefore are critical targets of conservation. We used an extensive literature and database review paired with expert interviews to estimate the global benefits of an increasingly used conservation action to stem biodiversity loss: eradication of invasive mammals on islands. We found 236 native terrestrial insular faunal species (596 populations) that benefitted through positive demographic and/or distributional responses from 251 eradications of invasive mammals on 181 islands. Seven native species (eight populations) were negatively impacted by invasive mammal eradication. Four threatened species had their International Union for the Conservation of Nature (IUCN) Red List extinction-risk categories reduced as a direct result of invasive mammal eradication, and no species moved to a higher extinction-risk category. We predict that 107 highly threatened birds, mammals, and reptiles on the IUCN Red List—6% of all these highly threatened species—likely have benefitted from invasive mammal eradications on islands. Because monitoring of eradication outcomes is sporadic and limited, the impacts of global eradications are likely greater than we report here. Our results highlight the importance of invasive mammal eradication on islands for protecting the world's most imperiled fauna. PMID:27001852

  14. Invasive mammal eradication on islands results in substantial conservation gains.

    PubMed

    Jones, Holly P; Holmes, Nick D; Butchart, Stuart H M; Tershy, Bernie R; Kappes, Peter J; Corkery, Ilse; Aguirre-Muñoz, Alfonso; Armstrong, Doug P; Bonnaud, Elsa; Burbidge, Andrew A; Campbell, Karl; Courchamp, Franck; Cowan, Philip E; Cuthbert, Richard J; Ebbert, Steve; Genovesi, Piero; Howald, Gregg R; Keitt, Bradford S; Kress, Stephen W; Miskelly, Colin M; Oppel, Steffen; Poncet, Sally; Rauzon, Mark J; Rocamora, Gérard; Russell, James C; Samaniego-Herrera, Araceli; Seddon, Philip J; Spatz, Dena R; Towns, David R; Croll, Donald A

    2016-04-12

    More than US$21 billion is spent annually on biodiversity conservation. Despite their importance for preventing or slowing extinctions and preserving biodiversity, conservation interventions are rarely assessed systematically for their global impact. Islands house a disproportionately higher amount of biodiversity compared with mainlands, much of which is highly threatened with extinction. Indeed, island species make up nearly two-thirds of recent extinctions. Islands therefore are critical targets of conservation. We used an extensive literature and database review paired with expert interviews to estimate the global benefits of an increasingly used conservation action to stem biodiversity loss: eradication of invasive mammals on islands. We found 236 native terrestrial insular faunal species (596 populations) that benefitted through positive demographic and/or distributional responses from 251 eradications of invasive mammals on 181 islands. Seven native species (eight populations) were negatively impacted by invasive mammal eradication. Four threatened species had their International Union for the Conservation of Nature (IUCN) Red List extinction-risk categories reduced as a direct result of invasive mammal eradication, and no species moved to a higher extinction-risk category. We predict that 107 highly threatened birds, mammals, and reptiles on the IUCN Red List-6% of all these highly threatened species-likely have benefitted from invasive mammal eradications on islands. Because monitoring of eradication outcomes is sporadic and limited, the impacts of global eradications are likely greater than we report here. Our results highlight the importance of invasive mammal eradication on islands for protecting the world's most imperiled fauna.

  15. Evolution of mammals and their gut microbes

    PubMed Central

    Ley, Ruth E.; Hamady, Micah; Lozupone, Catherine; Turnbaugh, Peter; Ramey, Rob Roy; Bircher, J. Stephen; Schlegel, Michael. L.; Tucker, Tammy A.; Schrenzel, Mark D.; Knight, Rob; Gordon, Jeffrey I.

    2009-01-01

    Mammals are metagenomic in that they are composed not only of their own gene complements but also those of all of their associated microbes. To understand the co-evolution of the mammals and their indigenous microbial communities, we conducted a network-based analysis of bacterial 16S rRNA gene sequences from the fecal microbiota of humans and 59 other mammalian species living in two zoos and the wild. The results indicate that host diet and phylogeny both influence bacterial diversity, which increases from carnivory to omnivory to herbivory, that bacterial communities co-diversified with their hosts, and that the gut microbiota of humans living a modern lifestyle is typical of omnivorous primates. PMID:18497261

  16. 50 CFR 18.25 - Exempted marine mammals or marine mammal products.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Exempted marine mammals or marine mammal... IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.25 Exempted marine mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply:...

  17. 50 CFR 216.25 - Exempted marine mammals and marine mammal products.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 10 2014-10-01 2014-10-01 false Exempted marine mammals and marine mammal... AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS General Exceptions § 216.25 Exempted marine mammals and marine...

  18. 50 CFR 18.25 - Exempted marine mammals or marine mammal products.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Exempted marine mammals or marine mammal... IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.25 Exempted marine mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply:...

  19. 50 CFR 18.25 - Exempted marine mammals or marine mammal products.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Exempted marine mammals or marine mammal... IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.25 Exempted marine mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply:...

  20. 50 CFR 216.25 - Exempted marine mammals and marine mammal products.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 10 2013-10-01 2013-10-01 false Exempted marine mammals and marine mammal... AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS General Exceptions § 216.25 Exempted marine mammals and marine...

  1. 50 CFR 216.25 - Exempted marine mammals and marine mammal products.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Exempted marine mammals and marine mammal... AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS General Exceptions § 216.25 Exempted marine mammals and marine...

  2. 50 CFR 216.25 - Exempted marine mammals and marine mammal products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Exempted marine mammals and marine mammal... AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS General Exceptions § 216.25 Exempted marine mammals and marine...

  3. 50 CFR 216.25 - Exempted marine mammals and marine mammal products.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Exempted marine mammals and marine mammal... AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS General Exceptions § 216.25 Exempted marine mammals and marine...

  4. 50 CFR 18.25 - Exempted marine mammals or marine mammal products.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Exempted marine mammals or marine mammal... IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.25 Exempted marine mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply:...

  5. 50 CFR 18.25 - Exempted marine mammals or marine mammal products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Exempted marine mammals or marine mammal... IMPORTATION OF WILDLIFE AND PLANTS (CONTINUED) MARINE MAMMALS General Exceptions § 18.25 Exempted marine mammals or marine mammal products. (a) The provisions of the Act and these regulations shall not apply:...

  6. Distribution of wild mammal assemblages along an urban-rural-forest landscape gradient in warm-temperate East Asia.

    PubMed

    Saito, Masayuki; Koike, Fumito

    2013-01-01

    Urbanization may alter mammal assemblages via habitat loss, food subsidies, and other factors related to human activities. The general distribution patterns of wild mammal assemblages along urban-rural-forest landscape gradients have not been studied, although many studies have focused on a single species or taxon, such as rodents. We quantitatively evaluated the effects of the urban-rural-forest gradient and spatial scale on the distributions of large and mid-sized mammals in the world's largest metropolitan area in warm-temperate Asia using nonspecific camera-trapping along two linear transects spanning from the urban zone in the Tokyo metropolitan area to surrounding rural and forest landscapes. Many large and mid-sized species generally decreased from forest landscapes to urban cores, although some species preferred anthropogenic landscapes. Sika deer (Cervus nippon), Reeves' muntjac (Muntiacus reevesi), Japanese macaque (Macaca fuscata), Japanese squirrel (Sciurus lis), Japanese marten (Martes melampus), Japanese badger (Meles anakuma), and wild boar (Sus scrofa) generally dominated the mammal assemblage of the forest landscape. Raccoon (Procyon lotor), raccoon dog (Nyctereutes procyonoides), and Japanese hare (Lepus brachyurus) dominated the mammal assemblage in the intermediate zone (i.e., rural and suburban landscape). Cats (feral and free-roaming housecats; Felis catus) were common in the urban assemblage. The key spatial scales for forest species were more than 4000-m radius, indicating that conservation and management plans for these mammal assemblages should be considered on large spatial scales. However, small green spaces will also be important for mammal conservation in the urban landscape, because an indigenous omnivore (raccoon dog) had a smaller key spatial scale (500-m radius) than those of forest mammals. Urbanization was generally the most important factor in the distributions of mammals, and it is necessary to consider the spatial scale of

  7. Distribution of Wild Mammal Assemblages along an Urban–Rural–Forest Landscape Gradient in Warm-Temperate East Asia

    PubMed Central

    Saito, Masayuki; Koike, Fumito

    2013-01-01

    Urbanization may alter mammal assemblages via habitat loss, food subsidies, and other factors related to human activities. The general distribution patterns of wild mammal assemblages along urban–rural–forest landscape gradients have not been studied, although many studies have focused on a single species or taxon, such as rodents. We quantitatively evaluated the effects of the urban–rural–forest gradient and spatial scale on the distributions of large and mid-sized mammals in the world's largest metropolitan area in warm-temperate Asia using nonspecific camera-trapping along two linear transects spanning from the urban zone in the Tokyo metropolitan area to surrounding rural and forest landscapes. Many large and mid-sized species generally decreased from forest landscapes to urban cores, although some species preferred anthropogenic landscapes. Sika deer (Cervus nippon), Reeves' muntjac (Muntiacus reevesi), Japanese macaque (Macaca fuscata), Japanese squirrel (Sciurus lis), Japanese marten (Martes melampus), Japanese badger (Meles anakuma), and wild boar (Sus scrofa) generally dominated the mammal assemblage of the forest landscape. Raccoon (Procyon lotor), raccoon dog (Nyctereutes procyonoides), and Japanese hare (Lepus brachyurus) dominated the mammal assemblage in the intermediate zone (i.e., rural and suburban landscape). Cats (feral and free-roaming housecats; Felis catus) were common in the urban assemblage. The key spatial scales for forest species were more than 4000-m radius, indicating that conservation and management plans for these mammal assemblages should be considered on large spatial scales. However, small green spaces will also be important for mammal conservation in the urban landscape, because an indigenous omnivore (raccoon dog) had a smaller key spatial scale (500-m radius) than those of forest mammals. Urbanization was generally the most important factor in the distributions of mammals, and it is necessary to consider the spatial

  8. Impact of non-native terrestrial mammals on the structure of the terrestrial mammal food web of Newfoundland, Canada.

    PubMed

    Strong, Justin S; Leroux, Shawn J

    2014-01-01

    The island of Newfoundland is unique because it has as many non-native terrestrial mammals as native ones. The impacts of non-native species on native flora and fauna can be profound and invasive species have been identified as one of the primary drivers of species extinction. Few studies, however, have investigated the effects of a non-native species assemblage on community and ecosystem properties. We reviewed the literature to build the first terrestrial mammal food web for the island of Newfoundland and then used network analyses to investigate how the timing of introductions and trophic position of non-native species has affected the structure of the terrestrial mammal food web in Newfoundland. The first non-native mammals (house mouse and brown rat) became established in Newfoundland with human settlement in the late 15th and early 16th centuries. Coyotes and southern red-backed voles are the most recent mammals to establish themselves on the island in 1985 and 1998, respectively. The fraction of intermediate species increased with the addition of non-native mammals over time whereas the fraction of basal and top species declined over time. This increase in intermediate species mediated by non-native species arrivals led to an overall increase in the terrestrial mammal food web connectance and generality (i.e. mean number of prey per predator). This diverse prey base and sources of carrion may have facilitated the natural establishment of coyotes on the island. Also, there is some evidence that the introduction of non-native prey species such as the southern red-backed vole has contributed to the recovery of the threatened American marten. Long-term monitoring of the food web is required to understand and predict the impacts of the diverse novel interactions that are developing in the terrestrial mammal food web of Newfoundland.

  9. Impact of Non-Native Terrestrial Mammals on the Structure of the Terrestrial Mammal Food Web of Newfoundland, Canada

    PubMed Central

    Strong, Justin S.; Leroux, Shawn J.

    2014-01-01

    The island of Newfoundland is unique because it has as many non-native terrestrial mammals as native ones. The impacts of non-native species on native flora and fauna can be profound and invasive species have been identified as one of the primary drivers of species extinction. Few studies, however, have investigated the effects of a non-native species assemblage on community and ecosystem properties. We reviewed the literature to build the first terrestrial mammal food web for the island of Newfoundland and then used network analyses to investigate how the timing of introductions and trophic position of non-native species has affected the structure of the terrestrial mammal food web in Newfoundland. The first non-native mammals (house mouse and brown rat) became established in Newfoundland with human settlement in the late 15th and early 16th centuries. Coyotes and southern red-backed voles are the most recent mammals to establish themselves on the island in 1985 and 1998, respectively. The fraction of intermediate species increased with the addition of non-native mammals over time whereas the fraction of basal and top species declined over time. This increase in intermediate species mediated by non-native species arrivals led to an overall increase in the terrestrial mammal food web connectance and generality (i.e. mean number of prey per predator). This diverse prey base and sources of carrion may have facilitated the natural establishment of coyotes on the island. Also, there is some evidence that the introduction of non-native prey species such as the southern red-backed vole has contributed to the recovery of the threatened American marten. Long-term monitoring of the food web is required to understand and predict the impacts of the diverse novel interactions that are developing in the terrestrial mammal food web of Newfoundland. PMID:25170923

  10. Impact of non-native terrestrial mammals on the structure of the terrestrial mammal food web of Newfoundland, Canada.

    PubMed

    Strong, Justin S; Leroux, Shawn J

    2014-01-01

    The island of Newfoundland is unique because it has as many non-native terrestrial mammals as native ones. The impacts of non-native species on native flora and fauna can be profound and invasive species have been identified as one of the primary drivers of species extinction. Few studies, however, have investigated the effects of a non-native species assemblage on community and ecosystem properties. We reviewed the literature to build the first terrestrial mammal food web for the island of Newfoundland and then used network analyses to investigate how the timing of introductions and trophic position of non-native species has affected the structure of the terrestrial mammal food web in Newfoundland. The first non-native mammals (house mouse and brown rat) became established in Newfoundland with human settlement in the late 15th and early 16th centuries. Coyotes and southern red-backed voles are the most recent mammals to establish themselves on the island in 1985 and 1998, respectively. The fraction of intermediate species increased with the addition of non-native mammals over time whereas the fraction of basal and top species declined over time. This increase in intermediate species mediated by non-native species arrivals led to an overall increase in the terrestrial mammal food web connectance and generality (i.e. mean number of prey per predator). This diverse prey base and sources of carrion may have facilitated the natural establishment of coyotes on the island. Also, there is some evidence that the introduction of non-native prey species such as the southern red-backed vole has contributed to the recovery of the threatened American marten. Long-term monitoring of the food web is required to understand and predict the impacts of the diverse novel interactions that are developing in the terrestrial mammal food web of Newfoundland. PMID:25170923

  11. Marine mammal neoplasia: a review.

    PubMed

    Newman, S J; Smith, S A

    2006-11-01

    A review of the published literature indicates that marine mammal neoplasia includes the types and distributions of tumors seen in domestic species. A routine collection of samples from marine mammal species is hampered, and, hence, the literature is principally composed of reports from early whaling expeditions, captive zoo mammals, and epizootics that affect larger numbers of animals from a specific geographic location. The latter instances are most important, because many of these long-lived, free-ranging marine mammals may act as environmental sentinels for the health of the oceans. Examination of large numbers of mortalities reveals incidental proliferative and neoplastic conditions and, less commonly, identifies specific malignant cancers that can alter population dynamics. The best example of these is the presumptive herpesvirus-associated metastatic genital carcinomas found in California sea lions. Studies of tissues from St. Lawrence estuary beluga whales have demonstrated a high incidence of neoplasia and produced evidence that environmental contamination with high levels of polychlorinated biphenols and dichlorophenyl trichloroethane might be the cause. In addition, viruses are suspected to be the cause of gastric papillomas in belugas and cutaneous papillomas in Florida manatees and harbor porpoises. While experimental laboratory procedures can further elucidate mechanisms of neoplasia, continued pathologic examination of marine mammals will also be necessary to follow trends in wild populations. PMID:17099143

  12. Eye shape and the nocturnal bottleneck of mammals

    PubMed Central

    Hall, Margaret I.; Kamilar, Jason M.; Kirk, E. Christopher

    2012-01-01

    Most vertebrate groups exhibit eye shapes that vary predictably with activity pattern. Nocturnal vertebrates typically have large corneas relative to eye size as an adaptation for increased visual sensitivity. Conversely, diurnal vertebrates generally demonstrate smaller corneas relative to eye size as an adaptation for increased visual acuity. By contrast, several studies have concluded that many mammals exhibit typical nocturnal eye shapes, regardless of activity pattern. However, a recent study has argued that new statistical methods allow eye shape to accurately predict activity patterns of mammals, including cathemeral species (animals that are equally likely to be awake and active at any time of day or night). Here, we conduct a detailed analysis of eye shape and activity pattern in mammals, using a broad comparative sample of 266 species. We find that the eye shapes of cathemeral mammals completely overlap with nocturnal and diurnal species. Additionally, most diurnal and cathemeral mammals have eye shapes that are most similar to those of nocturnal birds and lizards. The only mammalian clade that diverges from this pattern is anthropoids, which have convergently evolved eye shapes similar to those of diurnal birds and lizards. Our results provide additional evidence for a nocturnal ‘bottleneck’ in the early evolution of crown mammals. PMID:23097513

  13. Eye shape and the nocturnal bottleneck of mammals.

    PubMed

    Hall, Margaret I; Kamilar, Jason M; Kirk, E Christopher

    2012-12-22

    Most vertebrate groups exhibit eye shapes that vary predictably with activity pattern. Nocturnal vertebrates typically have large corneas relative to eye size as an adaptation for increased visual sensitivity. Conversely, diurnal vertebrates generally demonstrate smaller corneas relative to eye size as an adaptation for increased visual acuity. By contrast, several studies have concluded that many mammals exhibit typical nocturnal eye shapes, regardless of activity pattern. However, a recent study has argued that new statistical methods allow eye shape to accurately predict activity patterns of mammals, including cathemeral species (animals that are equally likely to be awake and active at any time of day or night). Here, we conduct a detailed analysis of eye shape and activity pattern in mammals, using a broad comparative sample of 266 species. We find that the eye shapes of cathemeral mammals completely overlap with nocturnal and diurnal species. Additionally, most diurnal and cathemeral mammals have eye shapes that are most similar to those of nocturnal birds and lizards. The only mammalian clade that diverges from this pattern is anthropoids, which have convergently evolved eye shapes similar to those of diurnal birds and lizards. Our results provide additional evidence for a nocturnal 'bottleneck' in the early evolution of crown mammals.

  14. Marine Mammal Impacts in Exploited Ecosystems: Would Large Scale Culling Benefit Fisheries?

    PubMed Central

    Morissette, Lyne; Christensen, Villy; Pauly, Daniel

    2012-01-01

    Competition between marine mammals and fisheries for marine resources—whether real or perceived—has become a major issue for several countries and in international fora. We examined trophic interactions between marine mammals and fisheries based on a resource overlap index, using seven Ecopath models including marine mammal groups. On a global scale, most food consumed by marine mammals consisted of prey types that were not the main target of fisheries. For each ecosystem, the primary production required (PPR) to sustain marine mammals was less than half the PPR to sustain fisheries catches. We also developed an index representing the mean trophic level of marine mammal's consumption (TLQ) and compared it with the mean trophic level of fisheries' catches (TLC). Our results showed that overall TLQ was lower than TLC (2.88 versus 3.42). As fisheries increasingly exploit lower-trophic level species, the competition with marine mammals may become more important. We used mixed trophic impact analysis to evaluate indirect trophic effects of marine mammals, and in some cases found beneficial effects on some prey. Finally, we assessed the change in the trophic structure of an ecosystem after a simulated extirpation of marine mammal populations. We found that this lead to alterations in the structure of the ecosystems, and that there was no clear and direct relationship between marine mammals' predation and the potential catch by fisheries. Indeed, total biomass, with no marine mammals in the ecosystem, generally remained surprisingly similar, or even decreased for some species. PMID:22970153

  15. Evaluating and interpreting cross-taxon congruence: Potential pitfalls and solutions

    NASA Astrophysics Data System (ADS)

    Gioria, Margherita; Bacaro, Giovanni; Feehan, John

    2011-05-01

    Characterizing the relationship between different taxonomic groups is critical to identify potential surrogates for biodiversity. Previous studies have shown that cross-taxa relationships are generally weak and/or inconsistent. The difficulties in finding predictive patterns have often been attributed to the spatial and temporal scales of these studies and on the differences in the measure used to evaluate such relationships (species richness versus composition). However, the choice of the analytical approach used to evaluate cross-taxon congruence inevitably represents a major source of variation. Here, we described the use of a range of methods that can be used to comprehensively assess cross-taxa relationships. To do so, we used data for two taxonomic groups, wetland plants and water beetles, collected from 54 farmland ponds in Ireland. Specifically, we used the Pearson correlation and rarefaction curves to analyse patterns in species richness, while Mantel tests, Procrustes analysis, and co-correspondence analysis were used to evaluate congruence in species composition. We compared the results of these analyses and we described some of the potential pitfalls associated with the use of each of these statistical approaches. Cross-taxon congruence was moderate to strong, depending on the choice of the analytical approach, on the nature of the response variable, and on local and environmental conditions. Our findings indicate that multiple approaches and measures of community structure are required for a comprehensive assessment of cross-taxa relationships. In particular, we showed that selection of surrogate taxa in conservation planning should not be based on a single statistic expressing the degree of correlation in species richness or composition. Potential solutions to the analytical issues associated with the assessment of cross-taxon congruence are provided and the implications of our findings in the selection of surrogates for biodiversity are discussed.

  16. [Wild is not really wild: brain weight of wild domestic mammals].

    PubMed

    Röhrs, M; Ebinger, P

    1999-01-01

    Domestication leads to the reduction of brain weight, decreases reach from 8.1% in laboratory rats up to 33.6% in domesticated pigs. The question is: Do brain weights increase by feralization? We compared the brain weights of domesticated mammals (cat, dog, pig, goat, ass) with their feral forms. In none of the cases studied, brain weight is increased in wild domestic mammals. So, feral mammals do not return back to the status of their wild species.

  17. Adaptive evolution toward larger size in mammals

    PubMed Central

    Baker, Joanna; Meade, Andrew; Pagel, Mark; Venditti, Chris

    2015-01-01

    The notion that large body size confers some intrinsic advantage to biological species has been debated for centuries. Using a phylogenetic statistical approach that allows the rate of body size evolution to vary across a phylogeny, we find a long-term directional bias toward increasing size in the mammals. This pattern holds separately in 10 of 11 orders for which sufficient data are available and arises from a tendency for accelerated rates of evolution to produce increases, but not decreases, in size. On a branch-by-branch basis, increases in body size have been more than twice as likely as decreases, yielding what amounts to millions and millions of years of rapid and repeated increases in size away from the small ancestral mammal. These results are the first evidence, to our knowledge, from extant species that are compatible with Cope’s rule: the pattern of body size increase through time observed in the mammalian fossil record. We show that this pattern is unlikely to be explained by several nonadaptive mechanisms for increasing size and most likely represents repeated responses to new selective circumstances. By demonstrating that it is possible to uncover ancient evolutionary trends from a combination of a phylogeny and appropriate statistical models, we illustrate how data from extant species can complement paleontological accounts of evolutionary history, opening up new avenues of investigation for both. PMID:25848031

  18. Competitive growth in a cooperative mammal.

    PubMed

    Huchard, Elise; English, Sinead; Bell, Matt B V; Thavarajah, Nathan; Clutton-Brock, Tim

    2016-05-26

    In many animal societies where hierarchies govern access to reproduction, the social rank of individuals is related to their age and weight and slow-growing animals may lose their place in breeding queues to younger 'challengers' that grow faster. The threat of being displaced might be expected to favour the evolution of competitive growth strategies, where individuals increase their own rate of growth in response to increases in the growth of potential rivals. Although growth rates have been shown to vary in relation to changes in the social environment in several vertebrates including fish and mammals, it is not yet known whether individuals increase their growth rates in response to increases in the growth of particular reproductive rivals. Here we show that, in wild Kalahari meerkats (Suricata suricatta), subordinates of both sexes respond to experimentally induced increases in the growth of same-sex rivals by raising their own growth rate and food intake. In addition, when individuals acquire dominant status, they show a secondary period of accelerated growth whose magnitude increases if the difference between their own weight and that of the heaviest subordinate of the same sex in their group is small. Our results show that individuals adjust their growth to the size of their closest competitor and raise the possibility that similar plastic responses to the risk of competition may occur in other social mammals, including domestic animals and primates. PMID:27225127

  19. Competitive growth in a cooperative mammal.

    PubMed

    Huchard, Elise; English, Sinead; Bell, Matt B V; Thavarajah, Nathan; Clutton-Brock, Tim

    2016-05-25

    In many animal societies where hierarchies govern access to reproduction, the social rank of individuals is related to their age and weight and slow-growing animals may lose their place in breeding queues to younger 'challengers' that grow faster. The threat of being displaced might be expected to favour the evolution of competitive growth strategies, where individuals increase their own rate of growth in response to increases in the growth of potential rivals. Although growth rates have been shown to vary in relation to changes in the social environment in several vertebrates including fish and mammals, it is not yet known whether individuals increase their growth rates in response to increases in the growth of particular reproductive rivals. Here we show that, in wild Kalahari meerkats (Suricata suricatta), subordinates of both sexes respond to experimentally induced increases in the growth of same-sex rivals by raising their own growth rate and food intake. In addition, when individuals acquire dominant status, they show a secondary period of accelerated growth whose magnitude increases if the difference between their own weight and that of the heaviest subordinate of the same sex in their group is small. Our results show that individuals adjust their growth to the size of their closest competitor and raise the possibility that similar plastic responses to the risk of competition may occur in other social mammals, including domestic animals and primates.

  20. Optical detection of marine mammals

    NASA Astrophysics Data System (ADS)

    Podobna, Yuliya; Schoonmaker, Jon; Boucher, Cynthia; Oakley, Daniel

    2009-05-01

    Advanced Coherent Technologies, LLC (ACT) is using a multi-spectral, multi-channel imaging system to detect and monitor marine mammals. The system, designed with US Navy funding, is intended to monitor mammals on US Navy submarine training ranges prior to and during Navy active acoustic training activities. ACT has conducted system tests and data collection activities at the St. Lawrence Seaway (Quebec, Canada), at Ma'alaea Bay (Maui, Hawaii), and from the Coronado Bay Bridge (San Diego, California). A description of the imaging system and the results of the data collections are discussed and presented.

  1. Tyrosine metabolic enzymes from insects and mammals: a comparative perspective.

    PubMed

    Vavricka, Christopher John; Han, Qian; Mehere, Prajwalini; Ding, Haizhen; Christensen, Bruce M; Li, Jianyong

    2014-02-01

    Differences in the metabolism of tyrosine between insects and mammals present an interesting example of molecular evolution. Both insects and mammals possess fine-tuned systems of enzymes to meet their specific demands for tyrosine metabolites; however, more homologous enzymes involved in tyrosine metabolism have emerged in many insect species. Without knowledge of modern genomics, one might suppose that mammals, which are generally more complex than insects and require tyrosine as a precursor for important catecholamine neurotransmitters and for melanin, should possess more enzymes to control tyrosine metabolism. Therefore, the question of why insects actually possess more tyrosine metabolic enzymes is quite interesting. It has long been known that insects rely heavily on tyrosine metabolism for cuticle hardening and for innate immune responses, and these evolutionary constraints are likely the key answers to this question. In terms of melanogenesis, mammals also possess a high level of regulation; yet mammalian systems possess more mechanisms for detoxification whereas insects accelerate pathways like melanogenesis and therefore must bear increased oxidative pressure. Our research group has had the opportunity to characterize the structure and function of many key proteins involved in tyrosine metabolism from both insects and mammals. In this mini review we will give a brief overview of our research on tyrosine metabolic enzymes in the scope of an evolutionary perspective of mammals in comparison to insects.

  2. Glucosylceramidases and malignancies in mammals.

    PubMed

    Astudillo, Leonardo; Therville, Nicole; Colacios, Céline; Ségui, Bruno; Andrieu-Abadie, Nathalie; Levade, Thierry

    2016-06-01

    Sphingolipids represent a major class of lipids that are essential constituents of eukaryotic cells. They are predominantly located in plasma membrane microdomains, and play an important structural role in regulating membrane fluidity. They are also bioactive effectors involved in diverse key cellular functions such as apoptosis and proliferation. The implication of some sphingolipids in cancer is well established whereas that of some others is still a matter of intense investigation. Glucosylceramide is the backbone of more than 300 structurally different glycosphingolipids including gangliosides and sulfatides, and is essential for mammalian development. Therefore, glucosylceramidases (also named GBA1, GBA2 and GBA3 β-glucosidases), the enzymes that hydrolyse β-glucosylceramide, play important functions. GBA1 is a lysosomal hydrolase whose deficiency causes Gaucher disease, the most prevalent inherited lysosomal storage disorder. GBA2 is a ubiquitous non-lysosomal glucosylceramidase whose mutations have been associated with some forms of hereditary spastic paraplegia. GBA3 is a cytosolic β-glucosidase, mostly present in the kidney, liver, spleen, intestine and lymphocytes of mammals, the function of which is still unclear. Whereas glucosylceramide synthase is implicated in multidrug resistance, the role of glucosylceramide breakdown in cancer is not yet fully appreciated. Defective GBA1 enzyme activity in humans, i.e., Gaucher disease, is associated with an increased risk of multiple myeloma and other malignancies. Putative molecular links between Gaucher disease and cancer, which might implicate the malignant cell and/or its microenvironment, are reviewed. The functions of GBA2 and GBA3 in cancer progression are also discussed.

  3. Delineating Species with DNA Barcodes: A Case of Taxon Dependent Method Performance in Moths

    PubMed Central

    Kekkonen, Mari; Mutanen, Marko; Kaila, Lauri; Nieminen, Marko; Hebert, Paul D. N.

    2015-01-01

    The accelerating loss of biodiversity has created a need for more effective ways to discover species. Novel algorithmic approaches for analyzing sequence data combined with rapidly expanding DNA barcode libraries provide a potential solution. While several analytical methods are available for the delineation of operational taxonomic units (OTUs), few studies have compared their performance. This study compares the performance of one morphology-based and four DNA-based (BIN, parsimony networks, ABGD, GMYC) methods on two groups of gelechioid moths. It examines 92 species of Finnish Gelechiinae and 103 species of Australian Elachistinae which were delineated by traditional taxonomy. The results reveal a striking difference in performance between the two taxa with all four DNA-based methods. OTU counts in the Elachistinae showed a wider range and a relatively low (ca. 65%) OTU match with reference species while OTU counts were more congruent and performance was higher (ca. 90%) in the Gelechiinae. Performance rose when only monophyletic species were compared, but the taxon-dependence remained. None of the DNA-based methods produced a correct match with non-monophyletic species, but singletons were handled well. A simulated test of morphospecies-grouping performed very poorly in revealing taxon diversity in these small, dull-colored moths. Despite the strong performance of analyses based on DNA barcodes, species delineated using single-locus mtDNA data are best viewed as OTUs that require validation by subsequent integrative taxonomic work. PMID:25849083

  4. 'Candidatus Phytoplasma malaysianum', a novel taxon associated with virescence and phyllody of Madagascar periwinkle (Catharanthus roseus).

    PubMed

    Nejat, Naghmeh; Vadamalai, Ganesan; Davis, Robert E; Harrison, Nigel A; Sijam, Kamaruzaman; Dickinson, Matthew; Abdullah, Siti Nor Akmar; Zhao, Yan

    2013-02-01

    This study addressed the taxonomic position and group classification of a phytoplasma responsible for virescence and phyllody symptoms in naturally diseased Madagascar periwinkle plants in western Malaysia. Unique regions in the 16S rRNA gene from the Malaysian periwinkle virescence (MaPV) phytoplasma distinguished the phytoplasma from all previously described 'Candidatus Phytoplasma' species. Pairwise sequence similarity scores, calculated through alignment of full-length 16S rRNA gene sequences, revealed that the MaPV phytoplasma 16S rRNA gene shared 96.5 % or less sequence similarity with that of previously described 'Ca. Phytoplasma' species, justifying the recognition of the MaPV phytoplasma as a reference strain of a novel taxon, 'Candidatus Phytoplasma malaysianum'. The 16S rRNA gene F2nR2 fragment from the MaPV phytoplasma exhibited a distinct restriction fragment length polymorphism (RFLP) profile and the pattern similarity coefficient values were lower than 0.85 with representative phytoplasmas classified in any of the 31 previously delineated 16Sr groups; therefore, the MaPV phytoplasma was designated a member of a new 16Sr group, 16SrXXXII. Phytoplasmas affiliated with this novel taxon and the new group included diverse strains infecting periwinkle, coconut palm and oil palm in Malaysia. Three phytoplasmas were characterized as representatives of three distinct subgroups, 16SrXXXII-A, 16SrXXXII-B and 16SrXXXII-C, respectively. PMID:22523165

  5. Delineating species with DNA barcodes: a case of taxon dependent method performance in moths.

    PubMed

    Kekkonen, Mari; Mutanen, Marko; Kaila, Lauri; Nieminen, Marko; Hebert, Paul D N

    2015-01-01

    The accelerating loss of biodiversity has created a need for more effective ways to discover species. Novel algorithmic approaches for analyzing sequence data combined with rapidly expanding DNA barcode libraries provide a potential solution. While several analytical methods are available for the delineation of operational taxonomic units (OTUs), few studies have compared their performance. This study compares the performance of one morphology-based and four DNA-based (BIN, parsimony networks, ABGD, GMYC) methods on two groups of gelechioid moths. It examines 92 species of Finnish Gelechiinae and 103 species of Australian Elachistinae which were delineated by traditional taxonomy. The results reveal a striking difference in performance between the two taxa with all four DNA-based methods. OTU counts in the Elachistinae showed a wider range and a relatively low (ca. 65%) OTU match with reference species while OTU counts were more congruent and performance was higher (ca. 90%) in the Gelechiinae. Performance rose when only monophyletic species were compared, but the taxon-dependence remained. None of the DNA-based methods produced a correct match with non-monophyletic species, but singletons were handled well. A simulated test of morphospecies-grouping performed very poorly in revealing taxon diversity in these small, dull-colored moths. Despite the strong performance of analyses based on DNA barcodes, species delineated using single-locus mtDNA data are best viewed as OTUs that require validation by subsequent integrative taxonomic work. PMID:25849083

  6. 75 FR 68605 - Marine Mammals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-08

    ... Register (75 FR 39915) that a request for a permit to conduct research on gray whales (Eschrictius robustus... National Oceanic and Atmospheric Administration RIN 0648-XX23 Marine Mammals AGENCY: National Marine... Marine Science Center, Newport, OR has been issued a permit to conduct research on marine...

  7. Blood Rheology in Marine Mammals

    PubMed Central

    Castellini, Michael A.; Baskurt, Oguz; Castellini, Judith M.; Meiselman, Herbert J.

    2010-01-01

    The field of blood oxygen transport and delivery to tissues has been studied by comparative physiologists for many decades. Within this general area, the particular differences in oxygen delivery between marine and terrestrial mammals has focused mainly on oxygen supply differences and delivery to the tissues under low blood flow diving conditions. Yet, the study of the inherent flow properties of the blood itself (hemorheology) is rarely discussed when addressing diving. However, hemorheology is important to the study of marine mammals because of the critical nature of the oxygen stores that are carried in the blood during diving periods. This review focuses on the essential elements of hemorheology, how they are defined and on fundamental rheological applications to marine mammals. While the comparative rationale used throughout the review is much broader than the particular problems associated with diving, the basic concepts focus on how changes in the flow properties of whole blood would be critical to oxygen delivery during diving. This review introduces the reader to most of the major rheological concepts that are relevant to the unique and unusual aspects of the diving physiology of marine mammals. PMID:21423386

  8. Resolving and dating the phylogeny of Cornales--Effects of taxon sampling, data partitions, and fossil calibrations.

    PubMed

    Xiang, Qiu-Yun Jenny; Thomas, David T; Xiang, Qiao Ping

    2011-04-01

    The order Cornales descends from the earliest split in the Asterid clade of flowering plants. Despite a few phylogenetic studies, relationships among families within Cornales remain unclear. In the present study, we increased taxon and character sampling to further resolve the relationships and to date the early diversification events of the order. We conducted phylogenetic analyses of sequence data from 26S rDNA and six chloroplast DNA (cpDNA) regions using parsimony (MP), maximum likelihood (ML), and Bayesian inference (BI) methods with different partition models and different data sets. We employed relaxed, uncorrelated molecular clocks on BEAST to date the phylogeny and examined the effects of different taxon sampling, fossil calibration, and data partitions. Our results from ML and BI analyses of the combined cpDNA sequences and combined cpDNA and 26S rDNA data suggested the monophyly of each family and the following familial relationships ((Cornaceae-Alangiaceae)-(Curtisiaceae-Grubbiaceae))-(((Nyssaceae-Davidiaceae)-Mastixiaceae)-((Hydrostachyaceae-(Hydrangeaceae-Loasaceae))). These relationships were strongly supported by posterior probability and bootstrap values, except for the sister relationship between the N-D-M and H-H-L clades. The 26S rDNA data and some MP trees from cpDNA and total evidence suggested some alternative alignments for Hydrostachyaceae within Cornales, but results of SH tests indicated that these trees were significantly worse explanations of the total data. Phylogenetic dating with simultaneous calibration of multiple nodes suggested that the crown group of Cornales originated around the middle Cretaceous and rapidly radiated into several major clades. The origins of most families dated back to the late Cretaceous except for Curtisiaceae and Grubbiaceae which may have diverged in the very early Tertiary. We found that reducing sampling density within families and analyzing partitioned data sets from coding and noncoding cpDNA, 26S r

  9. SMALL MAMMAL USE OF MICROHABITAT REVIEWED

    EPA Science Inventory

    Small mammal microhabitat research has greatly influenced vertebrate community ecologists. There exists a "microhabitat paradigm" that states that sympatry among small mammal species is enabled by differential use of microhabitat (i.e., microhabitat partitioning). However, seve...

  10. Quantifying the curvilinear metabolic scaling in mammals.

    PubMed

    Packard, Gary C

    2015-10-01

    A perplexing problem confronting students of metabolic allometry concerns the convex curvature that seemingly occurs in log-log plots of basal metabolic rate (BMR) vs. body mass in mammals. This putative curvilinearity has typically been interpreted in the context of a simple power function, Y=a*Xb, on the arithmetic scale, with the allometric exponent, b, supposedly increasing steadily as a dependent function of body size. The relationship can be quantified in arithmetic domain by exponentiating a quadratic equation fitted to logarithmic transformations of the original data, but the resulting model is not in the form of a power function and it is unlikely to describe accurately the pattern in the original distribution. I therefore re-examined a dataset for 636 species of mammal and discovered that the relationship between BMR and body mass is well-described by a power function with an explicit, non-zero intercept and lognormal, heteroscedastic error. The model has an invariant allometric exponent of 0.75, so the appearance in prior investigations of a steadily increasing exponent probably was an aberration resulting from undue reliance on logarithmic transformations to estimate statistical models in arithmetic domain. Theoretical constructs relating BMR to body mass in mammals may need to be modified to accommodate a positive intercept in the statistical model, but they do not need to be revised, or rejected, at present time on grounds that the allometric exponent varies with body size. New data from planned experiments will be needed to confirm any hypothesis based on data currently available.

  11. Arterial Windkessels in marine mammals.

    PubMed

    Shadwick, R E; Gosline, J M

    1995-01-01

    In marine mammals, the aortic arch is enlarged relative to the descending aorta to varying degrees in different species. The ratio of maximal diameter of the arch to that of the thoracic aorta is about 2.3 in the harbour seal (Phoca vitulina), 3.6 in the Weddell seal (Leptonychotes weddelli) and 3.2 in the fin whale (Balaenoptera physalus), compared with only 1.4 in the dog. This anatomical specialisation probably provides increased volume capacitance in the arterial circulation as an adaptation to diving bradycardia. Data on the morphometric and mechanical properties of aortic tissues from seals and fin whale are compared. In the harbour seal, more than 80% of the volume change in the entire thoracic aorta that results from a pressure pulse occurs in the bulbous arch, and this is more than 90% in the Weddell seal and fin whale. The enhanced capacitance of the arch in the harbour seal is primarily due to its larger diameter, as the relative wall thickness and elasticity of the arch and thoracic aorta are the same. A similar situation appears to exist in the larger Weddell seal, although extrapolation of the pressure-volume curves suggests that the arch might be somewhat less stiff than the thoracic aorta. In addition to being greatly expanded, the aortic arch of the fin whale is also much more distensible than the relatively thin-walled and much stiffer descending aorta. At the estimated mean blood pressure, the elastic modulus of this vessel is 12 MPa, or 30 times that of the aortic arch. The major haemodynamic consequence of this type of arterial modification is that the aortic arch acts as a Windkessel, i.e. the capacitance of the aorta is increased significantly close to the heart, leading to a reduced characteristic impedance and probably reduced pulsatility in the descending aorta. In the extreme case of the whale, the arterial capacitance is shifted entirely to the arch, and the impedance change at the entrance to the thoracic aorta is so high that this

  12. 50 CFR 14.18 - Marine mammals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... with the Marine Mammal Protection Act of 1972 and implementing regulations (50 CFR parts 18 and 216... 50 Wildlife and Fisheries 1 2012-10-01 2012-10-01 false Marine mammals. 14.18 Section 14.18....18 Marine mammals. Any person subject to the jurisdiction of the United States who has lawfully...

  13. 50 CFR 14.18 - Marine mammals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... with the Marine Mammal Protection Act of 1972 and implementing regulations (50 CFR parts 18 and 216... 50 Wildlife and Fisheries 1 2013-10-01 2013-10-01 false Marine mammals. 14.18 Section 14.18....18 Marine mammals. Any person subject to the jurisdiction of the United States who has lawfully...

  14. 50 CFR 14.18 - Marine mammals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... with the Marine Mammal Protection Act of 1972 and implementing regulations (50 CFR parts 18 and 216... 50 Wildlife and Fisheries 1 2014-10-01 2014-10-01 false Marine mammals. 14.18 Section 14.18....18 Marine mammals. Any person subject to the jurisdiction of the United States who has lawfully...

  15. 50 CFR 14.18 - Marine mammals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... with the Marine Mammal Protection Act of 1972 and implementing regulations (50 CFR parts 18 and 216... 50 Wildlife and Fisheries 1 2011-10-01 2011-10-01 false Marine mammals. 14.18 Section 14.18....18 Marine mammals. Any person subject to the jurisdiction of the United States who has lawfully...

  16. 50 CFR 14.18 - Marine mammals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... with the Marine Mammal Protection Act of 1972 and implementing regulations (50 CFR parts 18 and 216... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Marine mammals. 14.18 Section 14.18....18 Marine mammals. Any person subject to the jurisdiction of the United States who has lawfully...

  17. Behavioral thermoregulation in mammals: a review.

    PubMed

    Terrien, Jeremy; Perret, Martine; Aujard, Fabienne

    2011-01-01

    In mammals, thermoregulation is a key feature in the maintenance of homeostasis. Thermoregulatory capacities are strongly related to energy balance and animals are constantly seeking to limit the energy costs of normothermia. In case of thermal changes, physiological mechanisms are enhanced, increasing rates of energy expenditure. However, behavioral adjustments are available for species to lower the autonomic work, and thus reduce the energy costs of thermoregulatory responses. Hence, thermogenesis-induced metabolic costs can be reduced during cold exposure, and hyperthermia associated to dehydration can be avoided during heat exposure. Hypothermia avoidance consists in a concomitant decrease in heat dissipation and increase in heat production. Inversely, heat exchange is enhanced and body heat production is reduced when avoiding hyperthermia. The different behavioral strategies available for mammal species to cope with both decreased and increased levels of ambient temperature are reviewed. Moreover, thermoregulation function is under the control of central, metabolic, energetic and endocrine systems, which induces that parameters such as hour of the day, season, gender or aging may affect thermoregulatory adjustments. Some examples will be given. PMID:21196240

  18. OXYGEN POISONING IN MAMMALS.

    PubMed

    Binger, C A; Faulkner, J M; Moore, R L

    1927-04-30

    1. Oxygen in concentrations of over 70 per cent of an atmosphere is poisonous to dogs, rabbits, guinea pigs and mice. 2. The poisonous effects manifest themselves in drowsiness, anorexia, loss of weight, increasing dyspnea, cyanosis and death from oxygen want. 3. The cause of oxygen want is a destructive lesion of the lungs. 4. The lesion may be characterized grossly as an hemorrhagic edema. Microscopically there is to be seen in varying degrees of intensity (a) capillary engorgement with hemorrhage, (b) the presence of interstitial and intraalveolar serum, (c) hypertrophy and desquamation of alveolar cells, (d) interstitial and alveolar infiltration of mononuclear cells. 5. The type of tissue reaction is not characteristic of an infectious process and no organisms have been recovered at autopsy from the heart's blood or from lung puncture. 6. The poisonous effects of inhalations of oxygen-rich mixtures do not appear to be related to impurities in the oxygen, nor are they related to faulty ventilation, excessive moisture or increased carbon dioxide in the atmosphere of the chambers in which the experimental animals were confined. PMID:19869294

  19. First cranial remains of a gondwanatherian mammal reveal remarkable mosaicism

    NASA Astrophysics Data System (ADS)

    Krause, David W.; Hoffmann, Simone; Wible, John R.; Kirk, E. Christopher; Schultz, Julia A.; von Koenigswald, Wighart; Groenke, Joseph R.; Rossie, James B.; O'Connor, Patrick M.; Seiffert, Erik R.; Dumont, Elizabeth R.; Holloway, Waymon L.; Rogers, Raymond R.; Rahantarisoa, Lydia J.; Kemp, Addison D.; Andriamialison, Haingoson

    2014-11-01

    Previously known only from isolated teeth and lower jaw fragments recovered from the Cretaceous and Palaeogene of the Southern Hemisphere, the Gondwanatheria constitute the most poorly known of all major mammaliaform radiations. Here we report the discovery of the first skull material of a gondwanatherian, a complete and well-preserved cranium from Upper Cretaceous strata in Madagascar that we assign to a new genus and species. Phylogenetic analysis strongly supports its placement within Gondwanatheria, which are recognized as monophyletic and closely related to multituberculates, an evolutionarily successful clade of Mesozoic mammals known almost exclusively from the Northern Hemisphere. The new taxon is the largest known mammaliaform from the Mesozoic of Gondwana. Its craniofacial anatomy reveals that it was herbivorous, large-eyed and agile, with well-developed high-frequency hearing and a keen sense of smell. The cranium exhibits a mosaic of primitive and derived features, the disparity of which is extreme and probably reflective of a long evolutionary history in geographic isolation.

  20. Sesquiterpenes and flavonoid aglycones from a Hungarian taxon of the Achillea millefolium group.

    PubMed

    Glasl, Sabine; Mucaji, Pavel; Werner, Ingrid; Presser, Armin; Jurenitsch, Johann

    2002-01-01

    The investigation of a dichloromethane extract of flower heads of a Hungarian taxon of the Achillea millefolium group led to the isolation of three flavonoid aglycones, one triterpene, one germacranolide and five guaianolides. Their structures were elucidated by UV-VIS, EI- and CI-MS, 1H NMR and 13C NMR spectroscopic methods as well as by 2D-NMR studies and by selective 1D-NOE experiments. Besides apigenin, luteolin and centaureidin, beta-sitosterol, 3beta-hydroxy-11alpha,13-dihydro-costunolide, desacetylmatricarin, leucodin, achillin, 8alpha-angeloxy-leucodin and 8alpha-angeloxy-achillin were isolated. Both latter substances are reported here for the first time. Their NMR data were compared with those of the other guaianolides. The stereochemistry of 3beta-hydroxy-11alpha,13-dihydro-costunolide was discussed and compared with data of the literature.

  1. Development of taxon-specific sequences of common wheat for the detection of genetically modified wheat.

    PubMed

    Iida, Mayu; Yamashiro, Satomi; Yamakawa, Hirohito; Hayakawa, Katsuyuki; Kuribara, Hideo; Kodama, Takashi; Furui, Satoshi; Akiyama, Hiroshi; Maitani, Tamio; Hino, Akihiro

    2005-08-10

    Qualitative and quantitative Polymerase Chain Reaction (PCR) systems aimed at the specific detection and quantification of common wheat DNA are described. Many countries have issued regulations to label foods that include genetically modified organisms (GMOs). PCR technology is widely recognized as a reliable and useful technique for the qualitative and quantitative detection of GMOs. Detection methods are needed to amplify a target GM gene, and the amplified results should be compared with those of the corresponding taxon-specific reference gene to obtain reliable results. This paper describes the development of a specific DNA sequence in the waxy-D1 gene for common wheat (Triticum aestivum L.) and the design of a specific primer pair and TaqMan probe on the waxy-D1 gene for PCR analysis. The primers amplified a product (Wx012) of 102 bp. It is indicated that the Wx012 DNA sequence is specific to common wheat, showing homogeneity in qualitative PCR results and very similar quantification accuracy along 19 distantly related common wheat varieties. In Southern blot and real-time PCR analyses, this sequence showed either a single or a low number of copy genes. In addition, by qualitative and quantitative PCR using wx012 primers and a wx012-T probe, the limits of detection of the common wheat genome were found to be about 15 copies, and the reproducibility was reliable. In consequence, the PCR system using wx012 primers and wx012-T probe is considered to be suitable for use as a common wheat-specific taxon-specific reference gene in DNA analyses, including GMO tests.

  2. On the Complexity of the Saccharomyces bayanus Taxon: Hybridization and Potential Hybrid Speciation

    PubMed Central

    Pérez-Través, Laura; Lopes, Christian A.; Querol, Amparo; Barrio, Eladio

    2014-01-01

    Although the genus Saccharomyces has been thoroughly studied, some species in the genus has not yet been accurately resolved; an example is S. bayanus, a taxon that includes genetically diverse lineages of pure and hybrid strains. This diversity makes the assignation and classification of strains belonging to this species unclear and controversial. They have been subdivided by some authors into two varieties (bayanus and uvarum), which have been raised to the species level by others. In this work, we evaluate the complexity of 46 different strains included in the S. bayanus taxon by means of PCR-RFLP analysis and by sequencing of 34 gene regions and one mitochondrial gene. Using the sequence data, and based on the S. bayanus var. bayanus reference strain NBRC 1948, a hypothetical pure S. bayanus was reconstructed for these genes that showed alleles with similarity values lower than 97% with the S. bayanus var. uvarum strain CBS 7001, and of 99–100% with the non S. cerevisiae portion in S. pastorianus Weihenstephan 34/70 and with the new species S. eubayanus. Among the S. bayanus strains under study, different levels of homozygosity, hybridization and introgression were found; however, no pure S. bayanus var. bayanus strain was identified. These S. bayanus hybrids can be classified into two types: homozygous (type I) and heterozygous hybrids (type II), indicating that they have been originated by different hybridization processes. Therefore, a putative evolutionary scenario involving two different hybridization events between a S. bayanus var. uvarum and unknown European S. eubayanus-like strains can be postulated to explain the genomic diversity observed in our S. bayanus var. bayanus strains. PMID:24705561

  3. On the complexity of the Saccharomyces bayanus taxon: hybridization and potential hybrid speciation.

    PubMed

    Pérez-Través, Laura; Lopes, Christian A; Querol, Amparo; Barrio, Eladio

    2014-01-01

    Although the genus Saccharomyces has been thoroughly studied, some species in the genus has not yet been accurately resolved; an example is S. bayanus, a taxon that includes genetically diverse lineages of pure and hybrid strains. This diversity makes the assignation and classification of strains belonging to this species unclear and controversial. They have been subdivided by some authors into two varieties (bayanus and uvarum), which have been raised to the species level by others. In this work, we evaluate the complexity of 46 different strains included in the S. bayanus taxon by means of PCR-RFLP analysis and by sequencing of 34 gene regions and one mitochondrial gene. Using the sequence data, and based on the S. bayanus var. bayanus reference strain NBRC 1948, a hypothetical pure S. bayanus was reconstructed for these genes that showed alleles with similarity values lower than 97% with the S. bayanus var. uvarum strain CBS 7001, and of 99-100% with the non S. cerevisiae portion in S. pastorianus Weihenstephan 34/70 and with the new species S. eubayanus. Among the S. bayanus strains under study, different levels of homozygosity, hybridization and introgression were found; however, no pure S. bayanus var. bayanus strain was identified. These S. bayanus hybrids can be classified into two types: homozygous (type I) and heterozygous hybrids (type II), indicating that they have been originated by different hybridization processes. Therefore, a putative evolutionary scenario involving two different hybridization events between a S. bayanus var. uvarum and unknown European S. eubayanus-like strains can be postulated to explain the genomic diversity observed in our S. bayanus var. bayanus strains.

  4. Taxon interactions control the distributions of cryoconite bacteria colonizing a High Arctic ice cap.

    PubMed

    Gokul, Jarishma K; Hodson, Andrew J; Saetnan, Eli R; Irvine-Fynn, Tristram D L; Westall, Philippa J; Detheridge, Andrew P; Takeuchi, Nozomu; Bussell, Jennifer; Mur, Luis A J; Edwards, Arwyn

    2016-08-01

    Microbial colonization of glacial ice surfaces incurs feedbacks which affect the melting rate of the ice surface. Ecosystems formed as microbe-mineral aggregates termed cryoconite locally reduce ice surface albedo and represent foci of biodiversity and biogeochemical cycling. Consequently, greater understanding the ecological processes in the formation of functional cryoconite ecosystems upon glacier surfaces is sought. Here, we present the first bacterial biogeography of an ice cap, evaluating the respective roles of dispersal, environmental and biotic filtration occurring at local scales in the assembly of cryoconite microbiota. 16S rRNA gene amplicon semiconductor sequencing of cryoconite colonizing a Svalbard ice cap coupled with digital elevation modelling of physical parameters reveals the bacterial community is dominated by a ubiquitous core of generalist taxa, with evidence for a moderate pairwise distance-decay relationship. While geographic position and melt season duration are prominent among environmental predictors of community structure, the core population of taxa appears highly influential in structuring the bacterial community. Taxon co-occurrence network analysis reveals a highly modular community structured by positive interactions with bottleneck taxa, predominantly Actinobacteria affiliated to isolates from soil humus. In contrast, the filamentous cyanobacterial taxon (assigned to Leptolyngbya/Phormidesmis pristleyi) which dominates the community and binds together granular cryoconite are poorly connected to other taxa. While our study targeted one ice cap, the prominent role of generalist core taxa with close environmental relatives across the global cryosphere indicate discrete roles for cosmopolitan Actinobacteria and Cyanobacteria as respective keystone taxa and ecosystem engineers of cryoconite ecosystems colonizing ice caps. PMID:27261672

  5. Reproductive cycles of marine mammals.

    PubMed

    Pomeroy, P

    2011-04-01

    Marine mammals conform to the general mammalian reproductive system centered on the hypothalamic-pituitary-gonadal axis. Most marine mammals are long-lived and of large body size with lesser reproductive rates than many other animals, a consequence of their interaction with the marine environment where the demands of acquiring resources from the ocean must be balanced with the need for bearing offspring in a suitable place for survival. The degree of spatial and temporal separation of these life history phases in many species is a key feature of their ecology. The reproductive physiology of pinnipeds, cetaceans, sirenians, sea otters and polar bears has been more thoroughly characterized for the more accessible species.

  6. Morbillivirus infections in aquatic mammals.

    PubMed

    Visser, I K; van Bressem, M F; Barrett, T; Osterhaus, A D

    1993-01-01

    Infections with morbilliviruses have caused heavy losses among different populations of aquatic mammals during the last 5 years. Two different morbilliviruses were isolated from disease outbreaks among seals in Europe and Siberia: phocid distemper virus-1 (PDV-1) and phocid distemper virus-2 (PDV-2) respectively. PDV-1 was characterized as a newly identified morbillivirus, most related to canine distemper virus (CDV), whereas PDV-2 most probably is a strain of CDV. Morbilliviruses were also isolated from porpoises--porpoise morbillivirus (PMV)--and dolphins--dolphin morbillivirus (DMV)--which had stranded on the coasts of Europe. PMV and DMV proved to be closely related to, but distinct from 2 ruminant morbilliviruses, rinderpest virus (RPV) and peste-des-petits-ruminants virus (PPRV). Serological surveys carried out among pinniped and cetacean species in the seas of Europe and North America indicated that infections with these newly discovered morbilliviruses or closely related viruses commonly occur among aquatic mammal species. PMID:8343804

  7. Sexual Selection of Protamine 1 in Mammals.

    PubMed

    Lüke, Lena; Tourmente, Maximiliano; Roldan, Eduardo R S

    2016-01-01

    Protamines have a crucial role in male fertility. They are involved in sperm chromatin packaging and influence the shape of the sperm head and, hence, are important for sperm performance. Protamine structure is basic with numerous arginine-rich DNA-binding domains. Postcopulatory sexual selection is thought to play an important role in protamine sequence evolution and expression. Here, we analyze patterns of evolution and sexual selection (in the form of sperm competition) acting on protamine 1 gene sequence in 237 mammalian species. We assessed common patterns as well as differences between the major mammalian subclasses (Eutheria, Metatheria) and clades. We found that a high arginine content in protamine 1 associates with a lower sperm head width, which may have an impact on sperm swimming velocity. Increase in arginine content in protamine 1 across mammals appears to take place in a way consistent with sexual selection. In metatherians, increase in sequence length correlates with sexual selection. Differences in selective pressures on sequences and codon sites were observed between mammalian clades. Our study revealed a complex evolutionary pattern of protamine 1, with different selective constraints, and effects of sexual selection, between mammalian groups. In contrast, the effect of arginine content on head shape, and the possible involvement of sperm competition, was identified across all mammals.

  8. Anatomical adaptations of aquatic mammals.

    PubMed

    Reidenberg, Joy S

    2007-06-01

    This special issue of the Anatomical Record explores many of the anatomical adaptations exhibited by aquatic mammals that enable life in the water. Anatomical observations on a range of fossil and living marine and freshwater mammals are presented, including sirenians (manatees and dugongs), cetaceans (both baleen whales and toothed whales, including dolphins and porpoises), pinnipeds (seals, sea lions, and walruses), the sea otter, and the pygmy hippopotamus. A range of anatomical systems are covered in this issue, including the external form (integument, tail shape), nervous system (eye, ear, brain), musculoskeletal systems (cranium, mandible, hyoid, vertebral column, flipper/forelimb), digestive tract (teeth/tusks/baleen, tongue, stomach), and respiratory tract (larynx). Emphasis is placed on exploring anatomical function in the context of aquatic life. The following topics are addressed: evolution, sound production, sound reception, feeding, locomotion, buoyancy control, thermoregulation, cognition, and behavior. A variety of approaches and techniques are used to examine and characterize these adaptations, ranging from dissection, to histology, to electron microscopy, to two-dimensional (2D) and 3D computerized tomography, to experimental field tests of function. The articles in this issue are a blend of literature review and new, hypothesis-driven anatomical research, which highlight the special nature of anatomical form and function in aquatic mammals that enables their exquisite adaptation for life in such a challenging environment. PMID:17516440

  9. Dietary characterization of terrestrial mammals.

    PubMed

    Pineda-Munoz, Silvia; Alroy, John

    2014-08-22

    Understanding the feeding behaviour of the species that make up any ecosystem is essential for designing further research. Mammals have been studied intensively, but the criteria used for classifying their diets are far from being standardized. We built a database summarizing the dietary preferences of terrestrial mammals using published data regarding their stomach contents. We performed multivariate analyses in order to set up a standardized classification scheme. Ideally, food consumption percentages should be used instead of qualitative classifications. However, when highly detailed information is not available we propose classifying animals based on their main feeding resources. They should be classified as generalists when none of the feeding resources constitute over 50% of the diet. The term 'omnivore' should be avoided because it does not communicate all the complexity inherent to food choice. Moreover, the so-called omnivore diets actually involve several distinctive adaptations. Our dataset shows that terrestrial mammals are generally highly specialized and that some degree of food mixing may even be required for most species.

  10. Problems with the claim of ecotype and taxon status of the wolf in the Great Lakes region

    USGS Publications Warehouse

    Cronin, Matthew A.; Mech, L. David

    2009-01-01

    Koblmuller et al. (2009) analysed molecular genetic data of the wolf in the Great Lakes (GL) region of the USA and concluded that the animal was a unique ecotype of grey wolf and that genetic data supported the population as a discrete wolf taxon. However, some of the literature that the researchers used to support their position actually did not, and additional confusion arises from indefinite use of terminology. Herein, we discuss the problems with designation of a wolf population as a taxon or ecotype without proper definition and assessment of criteria.

  11. The nocturnal bottleneck and the evolution of activity patterns in mammals

    PubMed Central

    Gerkema, Menno P.; Davies, Wayne I. L.; Foster, Russell G.; Menaker, Michael; Hut, Roelof A.

    2013-01-01

    In 1942, Walls described the concept of a ‘nocturnal bottleneck’ in placental mammals, where these species could survive only by avoiding daytime activity during times in which dinosaurs were the dominant taxon. Walls based this concept of a longer episode of nocturnality in early eutherian mammals by comparing the visual systems of reptiles, birds and all three extant taxa of the mammalian lineage, namely the monotremes, marsupials (now included in the metatherians) and placentals (included in the eutherians). This review describes the status of what has become known as the nocturnal bottleneck hypothesis, giving an overview of the chronobiological patterns of activity. We review the ecological plausibility that the activity patterns of (early) eutherian mammals were restricted to the night, based on arguments relating to endothermia, energy balance, foraging and predation, taking into account recent palaeontological information. We also assess genes, relating to light detection (visual and non-visual systems) and the photolyase DNA protection system that were lost in the eutherian mammalian lineage. Our conclusion presently is that arguments in favour of the nocturnal bottleneck hypothesis in eutherians prevail. PMID:23825205

  12. The nocturnal bottleneck and the evolution of activity patterns in mammals.

    PubMed

    Gerkema, Menno P; Davies, Wayne I L; Foster, Russell G; Menaker, Michael; Hut, Roelof A

    2013-08-22

    In 1942, Walls described the concept of a 'nocturnal bottleneck' in placental mammals, where these species could survive only by avoiding daytime activity during times in which dinosaurs were the dominant taxon. Walls based this concept of a longer episode of nocturnality in early eutherian mammals by comparing the visual systems of reptiles, birds and all three extant taxa of the mammalian lineage, namely the monotremes, marsupials (now included in the metatherians) and placentals (included in the eutherians). This review describes the status of what has become known as the nocturnal bottleneck hypothesis, giving an overview of the chronobiological patterns of activity. We review the ecological plausibility that the activity patterns of (early) eutherian mammals were restricted to the night, based on arguments relating to endothermia, energy balance, foraging and predation, taking into account recent palaeontological information. We also assess genes, relating to light detection (visual and non-visual systems) and the photolyase DNA protection system that were lost in the eutherian mammalian lineage. Our conclusion presently is that arguments in favour of the nocturnal bottleneck hypothesis in eutherians prevail. PMID:23825205

  13. The nocturnal bottleneck and the evolution of activity patterns in mammals.

    PubMed

    Gerkema, Menno P; Davies, Wayne I L; Foster, Russell G; Menaker, Michael; Hut, Roelof A

    2013-08-22

    In 1942, Walls described the concept of a 'nocturnal bottleneck' in placental mammals, where these species could survive only by avoiding daytime activity during times in which dinosaurs were the dominant taxon. Walls based this concept of a longer episode of nocturnality in early eutherian mammals by comparing the visual systems of reptiles, birds and all three extant taxa of the mammalian lineage, namely the monotremes, marsupials (now included in the metatherians) and placentals (included in the eutherians). This review describes the status of what has become known as the nocturnal bottleneck hypothesis, giving an overview of the chronobiological patterns of activity. We review the ecological plausibility that the activity patterns of (early) eutherian mammals were restricted to the night, based on arguments relating to endothermia, energy balance, foraging and predation, taking into account recent palaeontological information. We also assess genes, relating to light detection (visual and non-visual systems) and the photolyase DNA protection system that were lost in the eutherian mammalian lineage. Our conclusion presently is that arguments in favour of the nocturnal bottleneck hypothesis in eutherians prevail.

  14. Introduced species: domestic mammals are more significant transmitters of parasites to native mammals than are feral mammals.

    PubMed

    Landaeta-Aqueveque, Carlos; Henríquez, Analía; Cattan, Pedro E

    2014-03-01

    The study of parasitism related to biological invasion has focused on attributes and impacts of parasites as invaders and the impact of introduced hosts on endemic parasitism. Thus, there is currently no study of the attributes of hosts which influence the invasiveness of parasites. We aimed to determine whether the degree of domestication of introduced mammalian species - feral introduced mammals, livestock or pets, hereafter 'D' - is important in the spillover of introduced parasites. The literature on introduced parasites of mammals in Chile was reviewed. We designed an index for estimating the relevance of the introduced host species to parasite spillover and determined whether the D of introduced mammals predicted this index. A total of 223 introduced parasite species were found. Our results indicate that domestic mammals have a higher number of introduced parasites and spillover parasites, and the index indicates that these mammals, particularly pets, are more relevant introducers than introduced feral mammals. Further analyses indicated that the higher impact is due to higher parasite richness, a longer time since introduction and wider dispersal, as well as how these mammals are maintained. The greater relevance of domestic mammals is important given that they are basically the same species distributed worldwide and can become the main transmitters of parasites to native mammals elsewhere. This finding also underlines the feasibility of management in order to reduce the transmission of parasites to native fauna through anti-parasitic treatment of domestic mammals, animal-ownership education and the prevention of importing new parasite species.

  15. Checklist of helminths found in Patagonian wild mammals.

    PubMed

    Fugassa, Martin H

    2015-01-01

    Using available reports, a checklist of the recorded helminth parasites of wild mammals from Patagonia was generated. Records of parasites found in Patagonia were included, together with records from mammals in áreas outside of Patagonia but whose range extends into Patagonia. Information about the host, localities, and references were also included. A total of 1323 records (224 Cestoda, 167 Trematoda, 894 Nematoda, 34 Acanthocephala, and 4 Pentastomida) belonging to 452 helminth species (77 Cestoda, 76 Trematoda, 277 Nematoda, 21 Acanthocephala, and 1 Pentastomida) found in 57 native mammals (22 Rodentia, 4 Didelphimorphia 1 Microbiotheria, 7 Chiroptera, 5 Cingulata, and 13 Carnivora) were listed. However, only 10.6 % of the reports were conducted on samples from Patagonia and corresponded to 25% of mammals in the region. In addition, many studies were made on a few species and, for example, 52% corresponded to studies made on Lama guanicoe. This suggests the need to increase efforts to know the parasitic fauna in a peculiar region as is the Patagonia. This is the first compilation of the helminth parasites of mammals in Argentine Patagonia and is important for parasitological and paleoparasitological studies. PMID:26623857

  16. Checklist of helminths found in Patagonian wild mammals.

    PubMed

    Fugassa, Martin H

    2015-09-03

    Using available reports, a checklist of the recorded helminth parasites of wild mammals from Patagonia was generated. Records of parasites found in Patagonia were included, together with records from mammals in áreas outside of Patagonia but whose range extends into Patagonia. Information about the host, localities, and references were also included. A total of 1323 records (224 Cestoda, 167 Trematoda, 894 Nematoda, 34 Acanthocephala, and 4 Pentastomida) belonging to 452 helminth species (77 Cestoda, 76 Trematoda, 277 Nematoda, 21 Acanthocephala, and 1 Pentastomida) found in 57 native mammals (22 Rodentia, 4 Didelphimorphia 1 Microbiotheria, 7 Chiroptera, 5 Cingulata, and 13 Carnivora) were listed. However, only 10.6 % of the reports were conducted on samples from Patagonia and corresponded to 25% of mammals in the region. In addition, many studies were made on a few species and, for example, 52% corresponded to studies made on Lama guanicoe. This suggests the need to increase efforts to know the parasitic fauna in a peculiar region as is the Patagonia. This is the first compilation of the helminth parasites of mammals in Argentine Patagonia and is important for parasitological and paleoparasitological studies.

  17. The Marine Mammal Protection Act at 40: status, recovery, and future of U.S. marine mammals.

    PubMed

    Roman, Joe; Altman, Irit; Dunphy-Daly, Meagan M; Campbell, Caitlin; Jasny, Michael; Read, Andrew J

    2013-05-01

    Passed in 1972, the Marine Mammal Protection Act has two fundamental objectives: to maintain U.S. marine mammal stocks at their optimum sustainable populations and to uphold their ecological role in the ocean. The current status of many marine mammal populations is considerably better than in 1972. Take reduction plans have been largely successful in reducing direct fisheries bycatch, although they have not been prepared for all at-risk stocks, and fisheries continue to place marine mammals as risk. Information on population trends is unknown for most (71%) stocks; more stocks with known trends are improving than declining: 19% increasing, 5% stable, and 5% decreasing. Challenges remain, however, and the act has generally been ineffective in treating indirect impacts, such as noise, disease, and prey depletion. Existing conservation measures have not protected large whales from fisheries interactions or ship strikes in the northwestern Atlantic. Despite these limitations, marine mammals within the U.S. Exclusive Economic Zone appear to be faring better than those outside, with fewer species in at-risk categories and more of least concern.

  18. The Marine Mammal Protection Act at 40: status, recovery, and future of U.S. marine mammals.

    PubMed

    Roman, Joe; Altman, Irit; Dunphy-Daly, Meagan M; Campbell, Caitlin; Jasny, Michael; Read, Andrew J

    2013-05-01

    Passed in 1972, the Marine Mammal Protection Act has two fundamental objectives: to maintain U.S. marine mammal stocks at their optimum sustainable populations and to uphold their ecological role in the ocean. The current status of many marine mammal populations is considerably better than in 1972. Take reduction plans have been largely successful in reducing direct fisheries bycatch, although they have not been prepared for all at-risk stocks, and fisheries continue to place marine mammals as risk. Information on population trends is unknown for most (71%) stocks; more stocks with known trends are improving than declining: 19% increasing, 5% stable, and 5% decreasing. Challenges remain, however, and the act has generally been ineffective in treating indirect impacts, such as noise, disease, and prey depletion. Existing conservation measures have not protected large whales from fisheries interactions or ship strikes in the northwestern Atlantic. Despite these limitations, marine mammals within the U.S. Exclusive Economic Zone appear to be faring better than those outside, with fewer species in at-risk categories and more of least concern. PMID:23521536

  19. Round table on morbilliviruses in marine mammals.

    PubMed

    Barrett, T; Blixenkrone-Møller, M; Domingo, M; Harder, T; Have, P; Liess, B; Orvell, C; Osterhaus, A D; Plana, J; Svansson, V

    1992-11-01

    Since 1988 morbilliviruses have been increasingly recognized and held responsible for mass mortality amongst harbour seals (Phoca vitulina) and other seal species. Virus isolations and characterization proved that morbilliviruses from seals in Northwest Europe were genetically distinct from other known members of this group including canine distemper virus (CDV), rinderpest virus, peste des petits ruminants virus and measles virus. An epidemic in Baikal seals in 1987 was apparently caused by a morbillivirus closely related to CDV so that two morbilliviruses have now been identified in two geographically distant seal populations, with only the group of isolates from Northwest Europe forming a new member of the genus morbillivirus: phocid distemper virus (PDV). Because of distemper-like disease, the Baikal seal morbillivirus was tentatively named PDV-2 in spite of its possible identity with CDV. The appearance of morbilliviruses in the Mediterranean Sea causing high mortality amongst dolphins should further increase the research activities on protection strategies for endangered species of marine mammals.

  20. The placental mammal ancestor and the post-K-Pg radiation of placentals.

    PubMed

    O'Leary, Maureen A; Bloch, Jonathan I; Flynn, John J; Gaudin, Timothy J; Giallombardo, Andres; Giannini, Norberto P; Goldberg, Suzann L; Kraatz, Brian P; Luo, Zhe-Xi; Meng, Jin; Ni, Xijun; Novacek, Michael J; Perini, Fernando A; Randall, Zachary S; Rougier, Guillermo W; Sargis, Eric J; Silcox, Mary T; Simmons, Nancy B; Spaulding, Michelle; Velazco, Paúl M; Weksler, Marcelo; Wible, John R; Cirranello, Andrea L

    2013-02-01

    To discover interordinal relationships of living and fossil placental mammals and the time of origin of placentals relative to the Cretaceous-Paleogene (K-Pg) boundary, we scored 4541 phenomic characters de novo for 86 fossil and living species. Combining these data with molecular sequences, we obtained a phylogenetic tree that, when calibrated with fossils, shows that crown clade Placentalia and placental orders originated after the K-Pg boundary. Many nodes discovered using molecular data are upheld, but phenomic signals overturn molecular signals to show Sundatheria (Dermoptera + Scandentia) as the sister taxon of Primates, a close link between Proboscidea (elephants) and Sirenia (sea cows), and the monophyly of echolocating Chiroptera (bats). Our tree suggests that Placentalia first split into Xenarthra and Epitheria; extinct New World species are the oldest members of Afrotheria.

  1. A new symmetrodont mammal (Trechnotheria: Zhangheotheriidae) from the Early Cretaceous of China and trechnotherian character evolution

    PubMed Central

    Bi, Shundong; Zheng, Xiaoting; Meng, Jin; Wang, Xiaoli; Robinson, Nicole; Davis, Brian

    2016-01-01

    We report the discovery of Anebodon luoi, a new genus and species of zhangheotheriid symmetrodont mammal from the Lujiatun site of the Lower Cretaceous Yixian Formation, China. The fossil is represented by an associated partial skull and dentaries with a nearly complete dentition, and with a dental formula of I4/3 C1/1 P5/4 M3/4. This new taxon lacks the high molar count typical of derived symmetrodonts, differing from the well-represented zhangheotheriids Zhangheotherium and Maotherium in having a postcanine dental formula that resembles more primitive tinodontid symmetrodonts on the one hand, and sister taxa to therians such as Peramus on the other. Upper and lower distal premolars are strongly molariform and are captured undergoing replacement, clarifying positional homology among related taxa. We also describe the rostrum and, for the first time in a symmetrodont, much of the orbital mosaic. Importantly, our new taxon occupies a basal position within the Zhangheotheriidae and permits discussion of trechnotherian character evolution, ultimately shedding additional light on the evolution of therians. PMID:27215593

  2. Marine mammals of Puerto Rico: a bibliography

    SciTech Connect

    Payne, S.F.

    1981-08-01

    This bibliography is the product of a literature survey on marine mammals at a proposed OTEC site near Punta Tuna, Puerto Rico. Included are reports of mammal sightings and strandings from Puerto Rico and adjacent Caribbean islands, reports containing information on distribution and abundance migration routes, and feeding ecology of those species known from the area. A few works on the general biology of marine mammals are also included. 96 references.

  3. Negevirus: a Proposed New Taxon of Insect-Specific Viruses with Wide Geographic Distribution

    PubMed Central

    Vasilakis, Nikos; Forrester, Naomi L.; Palacios, Gustavo; Nasar, Farooq; Savji, Nazir; Rossi, Shannan L.; Guzman, Hilda; Wood, Thomas G.; Popov, Vsevolod; Gorchakov, Rodion; González, Ana Vázquez; Haddow, Andrew D.; Watts, Douglas M.; da Rosa, Amelia P. A. Travassos; Weaver, Scott C.; Lipkin, W. Ian

    2013-01-01

    Six novel insect-specific viruses, isolated from mosquitoes and phlebotomine sand flies collected in Brazil, Peru, the United States, Ivory Coast, Israel, and Indonesia, are described. Their genomes consist of single-stranded, positive-sense RNAs with poly(A) tails. By electron microscopy, the virions appear as spherical particles with diameters of ∼45 to 55 nm. Based on their genome organization and phylogenetic relationship, the six viruses, designated Negev, Ngewotan, Piura, Loreto, Dezidougou, and Santana, appear to form a new taxon, tentatively designated Negevirus. Their closest but still distant relatives are citrus leposis virus C (CiLV-C) and viruses in the genus Cilevirus, which are mite-transmitted plant viruses. The negeviruses replicate rapidly and to high titer (up to 1010 PFU/ml) in mosquito cells, producing extensive cytopathic effect and plaques, but they do not appear to replicate in mammalian cells or mice. A discussion follows on their possible biological significance and effect on mosquito vector competence for arboviruses. PMID:23255793

  4. 'Candidatus Phytoplasma castaneae', a novel phytoplasma taxon associated with chestnut witches' broom disease.

    PubMed

    Jung, Hee-Young; Sawayanagi, Toshimi; Kakizawa, Shigeyuki; Nishigawa, Hisashi; Miyata, Shin-ichi; Oshima, Kenro; Ugaki, Masashi; Lee, Joon-Tak; Hibi, Tadaaki; Namba, Shigetou

    2002-09-01

    In Korea, Japanese chestnut trees (Castanea crenata Sieb. and Zucc.) showing symptoms indicative of witches' broom disease, including abnormally small leaves and yellowing of young leaves, were examined. Since the symptoms were suggestive of a phytoplasma infection, tissues were assayed for phytoplasmas by PCR analysis using a pair of universal primers that amplify a 1.4-kbp phytoplasma 16S rDNA fragment. The phytoplasma-specific fragment was amplified from diseased plants, but not from healthy plants, indicating that a phytoplasma was the causal agent of the chestnut witches' broom (CnWB) disease. The phylogenetic relationship of the CnWB phytoplasma to other phytoplasmas was examined by sequence analysis of the 16S rDNA. A phylogenetic analysis of 16S rDNA sequences of the phytoplasmas placed the CnWB phytoplasma within a distinct subgroup in the phytoplasma clade of the class Mollicutes. The phylogenetic tree indicated that the CnWB phytoplasma is related most closely to coconut phytoplasmas and suggested that they share a common ancestor. The unique properties of the CnWB phytoplasma sequences clearly establish that it represents a novel taxon, 'Candidatus Phytoplasma castaneae'.

  5. 'Candidatus Phytoplasma brasiliense', a new phytoplasma taxon associated with hibiscus witches' broom disease.

    PubMed

    Montano, H G; Davis, R E; Dally, E L; Hogenhout, S; Pimentel, J P; Brioso, P S

    2001-05-01

    Hibiscus rosa-sinensis is a valuable ornamental species widely planted in Brazil. Many plants are affected by witches' broom disease, which is characterized by excessive axillary branching, abnormally small leaves, and deformed flowers, symptoms that are characteristic of diseases attributed to phytoplasmas. A phytoplasma was detected in diseased Hibiscus by amplification of rRNA operon sequences by PCRs, and was characterized by RFLP and nucleotide sequence analyses of 16S rDNA. The collective RFLP patterns of amplified 16S rDNA differed from the patterns described previously for other phytoplasmas. On the basis of the RFLP patterns, the hibiscus witches' broom phytoplasma was classified in a new 16S rRNA RFLP group, designated group 16SrXV. A phylogenetic analysis of 16S rDNA sequences from this and other phytoplasmas identified the hibiscus witches' broom phytoplasma as a member of a distinct subclade (designated subclade xiv) of the class Mollicutes. A phylogenetic tree constructed on the basis of 16S rRNA gene sequences was consistent with the hypothesis that there was divergent evolution of hibiscus witches' broom phytoplasma and its closest relatives (members of 16S rRNA RFLP group 16SrII) from a common ancestor. On the basis of unique properties of the DNA from hibiscus witches' broom phytoplasma, it is proposed that it represents a new taxon, namely 'Candidatus Phytoplasma brasiliense'.

  6. Mycobacterial contamination of metalworking fluids: involvement of a possible new taxon of rapidly growing mycobacteria.

    PubMed

    Moore, J S; Christensen, M; Wilson, R W; Wallace, R J; Zhang, Y; Nash, D R; Shelton, B

    2000-01-01

    Contamination of air and metalworking fluid (MWF) systems with a rapidly growing mycobacterium (RGM) was detected in 1995 in a single manufacturing plant with recent cases of hypersensitivity pneumonitis (HP). Extensive environmental sampling was performed to determine the extent of the contamination and its variability over time. RGM were present in multiple indoor air samples, 100% of the central MWF storage tanks, and 75% of the freestanding cutting, drilling, and grinding machines. With one exception, contamination was limited to a recently introduced formulation (brand) of semisynthetic MWF used in 95% of the facility's machining operations. In general, the mycobacterial counts were stable over time, with the degree of contamination ranging from 10(2)-10(7) colony forming units (CFU)/mL. A few systems were culture positive for the mycobacterium (> 10(1) CFU/mL), changed to culture negative (< 10(1) CFU/mL), then changed back to culture positive without explanation. Samples obtained from diluted (5%) but unused MWF, a replenishment line with 2% unused MWF, an MWF pasteurizer, city water, and deionized water were culture negative for this species of mycobacterium. Inoculation and growth studies demonstrated that this mycobacterium does not grow in liquid samples of 5% unused MWF. By molecular techniques, the mycobacterial isolates consisted of a single strain and represented a previously undescribed taxon closely related to Mycobacterium chelonae/abscessus. The relationship of this mycobacterium to the cases of HP is unknown.

  7. Single-taxon field measurements of bacterial gene regulation controlling DMSP fate

    PubMed Central

    Varaljay, Vanessa A; Robidart, Julie; Preston, Christina M; Gifford, Scott M; Durham, Bryndan P; Burns, Andrew S; Ryan, John P; Marin III, Roman; Kiene, Ronald P; Zehr, Jonathan P; Scholin, Christopher A; Ann Moran, Mary

    2015-01-01

    The ‘bacterial switch' is a proposed regulatory point in the global sulfur cycle that routes dimethylsulfoniopropionate (DMSP) to two fundamentally different fates in seawater through genes encoding either the cleavage or demethylation pathway, and affects the flux of volatile sulfur from ocean surface waters to the atmosphere. Yet which ecological or physiological factors might control the bacterial switch remains a topic of considerable debate. Here we report the first field observations of dynamic changes in expression of DMSP pathway genes by a single marine bacterial species in its natural environment. Detection of taxon-specific gene expression in Roseobacter species HTCC2255 during a month-long deployment of an autonomous ocean sensor in Monterey Bay, CA captured in situ regulation of the first gene in each DMSP pathway (dddP and dmdA) that corresponded with shifts in the taxonomy of the phytoplankton community. Expression of the cleavage pathway was relatively greater during a high-DMSP-producing dinoflagellate bloom, and expression of the demethylation pathway was greater in the presence of a mixed diatom and dinoflagellate community. These field data fit the prevailing hypothesis for bacterial DMSP gene regulation based on bacterial sulfur demand, but also suggest a modification involving oxidative stress response, evidenced as upregulation of catalase via katG, when DMSP is demethylated. PMID:25700338

  8. Cytological and molecular characterization of Vicia esdraelonensis Warb. & Eig: a rare taxon.

    PubMed

    Ruffini Castiglione, M; Frediani, M; Gelati, M T; Ravalli, C; Venora, G; Caputo, P; Cremonini, R

    2007-01-01

    Vicia esdraelonensis, a rare taxon belonging to section Hypechusa of subgenus Vicia, was recovered and analyzed by cytological, karyological, and molecular methods, with the aim of both characterizing this species and furthering our knowledge of the phylogeny of subgenus Vicia. Automated karyotype analysis, nuclear DNA content, and chromatin organization were determined by the Feulgen reaction, as well as chromosome banding after double staining with 4',6-diamidino-2-phenylindole (DAPI) and chromomycin A3. The chromosome number and the nuclear DNA content were in agreement with the values of the species of section Hypechusa. The GC- and AT-rich preferential sites were determined by chromomycin A3 and DAPI staining. Karyomorphological parameters indicated that V. esdraelonensis is in an intermediate position in the spatial representation of the species of section Hypechusa on the basis of symmetry indices, as well as in the dendrogram of linkage distance constructed on 37 chromosome parameters. Molecular data based on internal transcribed spacer sequences show that V. esdraelonensis can doubtlessly be included in section Hypechusa and document its closeness to V. noeana. A cladistic analysis combining the molecular data set with karyological characters is also reported. Karyological, cytological, and molecular data allow characterization of the V. esdraelonensis genome and provide information about the phylogenetic position of this species within the Hyrcanicae series of section Hypechusa.

  9. The cephalic morphology of the Gondwanan key taxon Hackeriella (Coleorrhyncha, Hemiptera).

    PubMed

    Spangenberg, Rico; Wipfler, Benjamin; Friedemann, Katrin; Pohl, Hans; Weirauch, Christiane; Hartung, Viktor; Beutel, Rolf G

    2013-07-01

    External and internal head structures of Coleorrhyncha, a key-taxon within the Hemiptera, are described in detail and documented using modern techniques. The main focus is on Hackeriella veitchi, but two additional representatives of the Gondwanan relict group were also examined, and also head structures of Enicocephalidae, a member of a potentially basal heteropteran lineage. Features were compared to those documented in literature for the Sternorrhyncha, Auchenorrhyncha, and Heteroptera. Coleorrhyncha are characterized by highly modified head structures and correspondingly an entire series of autapomorphies, such as for instance a strongly flattened head capsule with fenestrations. However, they also display features that are likely plesiomorphic compared to members of other hemipteran groups. These include the almost complete tentorium and the lack of the gula. The sistergroup relationship between Coleorrhyncha and Heteroptera is well supported by cephalic features. Potential synapomorphies are the presence of a distinct mandibular sulcus, the reduced number of antennomeres, the absence of clasping organs in the labial groove, coiled accessory salivary ducts, the presence of a small cervical muscle M1a (M. pronotopostoccipitalis medialis), the presence of a second mandibular promotor M14 (M. zygomaticus mandibulae), the presence of M28 (M. verticopharyngalis), and M30 (M. frontobuccalis posterior). PMID:23583344

  10. Biological richness of a large urban cemetery in Berlin. Results of a multi-taxon approach

    PubMed Central

    Blick, Theo; Hannig, Karsten; Kowarik, Ingo; Lemke, Andreas; Otte, Volker; Scharon, Jens; Schönhofer, Axel; Teige, Tobias; von der Lippe, Moritz; Seitz, Birgit

    2016-01-01

    Abstract Background Urban green spaces can harbor a considerable species richness of plants and animals. A few studies on single species groups indicate important habitat functions of cemeteries, but this land use type is clearly understudied compared to parks. Such data are important as they (i) illustrate habitat functions of a specific, but ubiquitous urban land-use type and (ii) may serve as a basis for management approaches. New information We sampled different groups of plants and animals in the Weißensee Jewish Cemetery in Berlin (WJC) which is one of the largest Jewish cemeteries in Europe. With a total of 608 species of plants and animals, this first multi-taxon survey revealed a considerable biological richness in the WJC. In all, 363 wild-growing vascular plant, 72 lichen and 26 bryophyte taxa were recorded. The sampling also yielded 34 bird and 5 bat species as well as 39 ground beetle, 5 harvestman and 64 spider species. Some species are new records for Berlin. PMID:27099549

  11. Integration of approaches in David Wake's model-taxon research platform for evolutionary morphology.

    PubMed

    Griesemer, James

    2013-12-01

    What gets integrated in integrative scientific practices has been a topic of much discussion. Traditional views focus on theories and explanations, with ideas of reduction and unification dominating the conversation. More recent ideas focus on disciplines, fields, or specialties; models, mechanisms, or methods; phenomena, problems. How integration works looks different on each of these views since the objects of integration are ontologically and epistemically various: statements, boundary conditions, practices, protocols, methods, variables, parameters, domains, laboratories, and questions all have their own structures, functions and logics. I focus on one particular kind of scientific practice, integration of "approaches" in the context of a research system operating on a special kind of "platform." Rather than trace a network of interactions among people, practices, and theoretical entities to be integrated, in this essay I focus on the work of a single investigator, David Wake. I describe Wake's practice of integrative evolutionary biology and how his integration of approaches among biological specialties worked in tandem with his development of the salamanders as a model taxon, which he used as a platform to solve, re-work and update problems that would not have been solved so well by non-integrative approaches. The larger goal of the project to which this paper contributes is a counter-narrative to the story of 20th century life sciences as the rise and march of the model organisms and decline of natural history.

  12. A New Taxon of Basal Ceratopsian from China and the Early Evolution of Ceratopsia.

    PubMed

    Han, Fenglu; Forster, Catherine A; Clark, James M; Xu, Xing

    2015-01-01

    Ceratopsia is one of the best studied herbivorous ornithischian clades, but the early evolution of Ceratopsia, including the placement of Psittacosaurus, is still controversial and unclear. Here, we report a second basal ceratopsian, Hualianceratops wucaiwanensis gen. et sp. nov., from the Upper Jurassic (Oxfordian) Shishugou Formation of the Junggar Basin, northwestern China. This new taxon is characterized by a prominent caudodorsal process on the subtemporal ramus of the jugal, a robust quadrate with an expansive quadratojugal facet, a prominent notch near the ventral region of the quadrate, a deep and short dentary, and strongly rugose texturing on the lateral surface of the dentary. Hualianceratops shares several derived characters with both Psittacosaurus and the basal ceratopsians Yinlong, Chaoyangsaurus, and Xuanhuaceratops. A new comprehensive phylogeny of ceratopsians weakly supports both Yinlong and Hualianceratops as chaoyangsaurids (along with Chaoyangsaurus and Xuanhuaceratops), as well as the monophyly of Chaoyangosauridae + Psittacosaurus. This analysis also weakly supports the novel hypothesis that Chaoyangsauridae + Psittacosaurus is the sister group to the rest of Neoceratopsia, suggesting a basal split between these clades before the Late Jurassic. This phylogeny and the earliest Late Jurassic age of Yinlong and Hualianceratops imply that at least five ceratopsian lineages (Yinlong, Hualianceratops, Chaoyangsaurus + Xuanhuaceratops, Psittacosaurus, Neoceratopsia) were present at the beginning of the Late Jurassic. PMID:26649770

  13. A New Taxon of Basal Ceratopsian from China and the Early Evolution of Ceratopsia

    PubMed Central

    Han, Fenglu; Forster, Catherine A.; Clark, James M.; Xu, Xing

    2015-01-01

    Ceratopsia is one of the best studied herbivorous ornithischian clades, but the early evolution of Ceratopsia, including the placement of Psittacosaurus, is still controversial and unclear. Here, we report a second basal ceratopsian, Hualianceratops wucaiwanensis gen. et sp. nov., from the Upper Jurassic (Oxfordian) Shishugou Formation of the Junggar Basin, northwestern China. This new taxon is characterized by a prominent caudodorsal process on the subtemporal ramus of the jugal, a robust quadrate with an expansive quadratojugal facet, a prominent notch near the ventral region of the quadrate, a deep and short dentary, and strongly rugose texturing on the lateral surface of the dentary. Hualianceratops shares several derived characters with both Psittacosaurus and the basal ceratopsians Yinlong, Chaoyangsaurus, and Xuanhuaceratops. A new comprehensive phylogeny of ceratopsians weakly supports both Yinlong and Hualianceratops as chaoyangsaurids (along with Chaoyangsaurus and Xuanhuaceratops), as well as the monophyly of Chaoyangosauridae + Psittacosaurus. This analysis also weakly supports the novel hypothesis that Chaoyangsauridae + Psittacosaurus is the sister group to the rest of Neoceratopsia, suggesting a basal split between these clades before the Late Jurassic. This phylogeny and the earliest Late Jurassic age of Yinlong and Hualianceratops imply that at least five ceratopsian lineages (Yinlong, Hualianceratops, Chaoyangsaurus + Xuanhuaceratops, Psittacosaurus, Neoceratopsia) were present at the beginning of the Late Jurassic. PMID:26649770

  14. Influence of alternative silviculture on small mammals

    USGS Publications Warehouse

    Waldien, David L.; Hayes, John P.

    2006-01-01

    HIGHLIGHT: A variety of harvest methods promote diversity within forests while still generating income. For example, recent studies have shown that when dead wood is left on the forest floor during harvest, biodiversity increases. A new Cooperative Forest Ecosystem Research (CFER) program fact sheet summarizes how small mammals respond to dead wood in forests that are harvested with alternative methods. CFER is developing a series of fact sheets about responses to changes in young western Oregon forests. The fact sheets are designed to help resource managers balance management needs, including timber and wildlife. The USGS provides a primary source of financial support for CFER, a consortium of federal and state partners conducting research in support of the Northwest Forest Plan.

  15. Mammal extinctions, body size, and paleotemperature

    USGS Publications Warehouse

    Bown, T.M.; Holroyd, P.A.; Rose, K.D.

    1994-01-01

    There is a general inverse relationship between the natural logarithm of tooth area (a body size indicator) of some fossil mammals and paleotemperature during approximately 2.9 million years of the early Eocene in the Bighorn Basin of northwest Wyoming. When mean temperatures became warmer, tooth areas tended to become smaller. During colder times, larger species predominated; these generally became larger or remained the same size. Paleotemperature trends also markedly affected patterns of local (and, perhaps, regional) extinction and immigration. New species appeared as immigrants during or near the hottest (smaller forms) and coldest (larger forms) intervals. Paleotemperature trend reversals commonly resulted in the ultimate extinction of both small forms (during cooling intervals) and larger forms (during warming intervals). These immigrations and extinctions mark faunal turnovers that were also modulated by sharp increases in sediment accumulation rate.

  16. Missing Data and Influential Sites: Choice of Sites for Phylogenetic Analysis Can Be As Important As Taxon Sampling and Model Choice

    PubMed Central

    Shavit Grievink, Liat; Penny, David; Holland, Barbara R.

    2013-01-01

    Phylogenetic studies based on molecular sequence alignments are expected to become more accurate as the number of sites in the alignments increases. With the advent of genomic-scale data, where alignments have very large numbers of sites, bootstrap values close to 100% and posterior probabilities close to 1 are the norm, suggesting that the number of sites is now seldom a limiting factor on phylogenetic accuracy. This provokes the question, should we be fussy about the sites we choose to include in a genomic-scale phylogenetic analysis? If some sites contain missing data, ambiguous character states, or gaps, then why not just throw them away before conducting the phylogenetic analysis? Indeed, this is exactly the approach taken in many phylogenetic studies. Here, we present an example where the decision on how to treat sites with missing data is of equal importance to decisions on taxon sampling and model choice, and we introduce a graphical method for illustrating this. PMID:23471508

  17. Marine mammal impacts in exploited ecosystems: would large scale culling benefit fisheries?

    PubMed

    Morissette, Lyne; Christensen, Villy; Pauly, Daniel

    2012-01-01

    Competition between marine mammals and fisheries for marine resources-whether real or perceived-has become a major issue for several countries and in international fora. We examined trophic interactions between marine mammals and fisheries based on a resource overlap index, using seven Ecopath models including marine mammal groups. On a global scale, most food consumed by marine mammals consisted of prey types that were not the main target of fisheries. For each ecosystem, the primary production required (PPR) to sustain marine mammals was less than half the PPR to sustain fisheries catches. We also developed an index representing the mean trophic level of marine mammal's consumption (TL(Q)) and compared it with the mean trophic level of fisheries' catches (TL(C)). Our results showed that overall TL(Q) was lower than TL(C) (2.88 versus 3.42). As fisheries increasingly exploit lower-trophic level species, the competition with marine mammals may become more important. We used mixed trophic impact analysis to evaluate indirect trophic effects of marine mammals, and in some cases found beneficial effects on some prey. Finally, we assessed the change in the trophic structure of an ecosystem after a simulated extirpation of marine mammal populations. We found that this lead to alterations in the structure of the ecosystems, and that there was no clear and direct relationship between marine mammals' predation and the potential catch by fisheries. Indeed, total biomass, with no marine mammals in the ecosystem, generally remained surprisingly similar, or even decreased for some species.

  18. Fatty Acid use in Diving Mammals: More than Merely Fuel

    PubMed Central

    Trumble, Stephen J.; Kanatous, Shane B.

    2012-01-01

    Diving mammals, are under extreme pressure to conserve oxygen as well as produce adequate energy through aerobic pathways during breath-hold diving. Typically a major source of energy, lipids participate in structural and regulatory roles and have an important influence on the physiological functions of an organism. At the stoichiometric level, the metabolism of polyunsaturated fatty acids (PUFAs) utilizes less oxygen than metabolizing either monounsaturated fatty acids or saturated fatty acids (SFAs) and yields fewer ATP per same length fatty acid. However, there is evidence that indicates the cellular metabolic rate is directly correlated to the lipid composition of the membranes such that the greater the PUFA concentration in the membranes the greater the metabolic rate. These findings appear to be incompatible with diving mammals that ingest and metabolize high levels of unsaturated fatty acids while relying on stored oxygen. Growing evidence from birds to mammals including recent evidence in Weddell seals also indicates that at the whole animal level the utilization of PUFAs to fuel their metabolism actually conserves oxygen. In this paper, we make an initial attempt to ascertain the beneficial adaptations or limitations of lipids constituents and potential trade-offs in diving mammals. We discuss how changes in Antarctic climate are predicted to have numerous different environmental effects; such potential shifts in the availability of certain prey species or even changes in the lipid composition (increased SFA) of numerous fish species with increasing water temperatures and how this may impact the diving ability of Weddell seals. PMID:22707938

  19. 50 CFR 216.37 - Marine mammal parts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 10 2014-10-01 2014-10-01 false Marine mammal parts. 216.37 Section 216... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Special Exceptions § 216.37 Marine mammal parts. With respect to marine mammal parts acquired...

  20. 50 CFR 216.37 - Marine mammal parts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 10 2013-10-01 2013-10-01 false Marine mammal parts. 216.37 Section 216... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Special Exceptions § 216.37 Marine mammal parts. With respect to marine mammal parts acquired...

  1. 50 CFR 216.37 - Marine mammal parts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Marine mammal parts. 216.37 Section 216... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Special Exceptions § 216.37 Marine mammal parts. With respect to marine mammal parts acquired...

  2. 50 CFR 216.83 - Importation of birds or mammals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Importation of birds or mammals. 216.83... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Pribilof Islands Administration § 216.83 Importation of birds or mammals. No mammals or...

  3. 50 CFR 216.37 - Marine mammal parts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Marine mammal parts. 216.37 Section 216.37..., DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Special Exceptions § 216.37 Marine mammal parts. With respect to marine mammal parts acquired by take...

  4. 50 CFR 216.37 - Marine mammal parts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Marine mammal parts. 216.37 Section 216.37..., DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Special Exceptions § 216.37 Marine mammal parts. With respect to marine mammal parts acquired by take...

  5. 50 CFR 216.83 - Importation of birds or mammals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Importation of birds or mammals. 216.83... ADMINISTRATION, DEPARTMENT OF COMMERCE MARINE MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Pribilof Islands Administration § 216.83 Importation of birds or mammals. No mammals or...

  6. Report on marine mammal stranding

    NASA Astrophysics Data System (ADS)

    Kumar, Mohi

    2006-06-01

    The U.S. National Oceanic and Atmospheric Administration (NOAA) released a report on 27 April indicating that U.S. Navy sonar transmissions may have played a role in the stranding of more than 150 melon-headed whales on 3 July 2004 off the coast of Kauai, Hawaii. At the time of the stranding, which resulted in one whale death, the Navy was preparing to conduct sonar activities as part of a military exercise. The report notes that six naval surface vessels transiting to the area on the previous night intermittenly transmitted mid-frequency active sonar. That activity is ``a plausible, if not likely, contributing factor'' to the stranding event. There was no significant weather, natural oceanographic event, or known biological factors that would explain the animals' movement into the bay nor the group's continued presence in the bay, according to report lead author Teri Rowles, NOAA marine mammal veterinarian.

  7. Taxon-specific growth and selective microzooplankton grazing of phytoplankton in the Northeast Atlantic

    NASA Astrophysics Data System (ADS)

    Gaul, Wilhelm; Antia, Avan N.

    2001-10-01

    Taxon-specific microzooplankton dynamics were studied along a transect through the North Atlantic Drift from 70°N 04°E to 40°N 20°W during July 1997 using serial dilution and nutrient-enrichment experiments. Nutrient concentrations and microzooplankton composition indicated postbloom conditions at 40°N, 47°N, and 50°N, a transitional system at 54°N, and bloom conditions at 62°N and 70°N. The ratio of microzooplankton to phytoplankton biomass was inversely related to nitrate and phosphate concentrations. Potential grazing thresholds were observed in four of nine experiments at 40-66% of the initial phytoplankton concentration. Grazing losses were determined for six pigment-specific classes of phytoplankton. Selective grazing losses of phytoplankton taxa ranged from 73% to 248% of the nonselective grazing losses predicted according to their biomass contributions. The grazing selectivity varied considerably between communities, with the microherbivores showing positive selection for cyanobacteria and dinoflagellates and predominantly avoidance of chlorophyta and bacillariophyceae. Microzooplankton did not show a preference for the dominant phytoplankton taxa, but grazed preferentially on fast-growing phytoplankton with minor contributions (<15%) to the phytoplankton biomass. However, bacillariophyceae were the major contributors to phytoplankton biomass and accounted for major fractions of the total losses through microzooplankton grazing. Microzooplankton consumed the equivalent of 0.12-5.5 times their own biomass daily on a carbon basis, amounting to 65-197% of gross phytoplankton production. With the conservative assumption that 20% of the consumed phytoplankton was converted to microzooplankton biomass, the latter was estimated to contribute 27-381% to the net production of the entire microzooplankton community. We therefore conclude that the taxonomic structure and the net production of the microzooplankton communities were significantly affected by the

  8. A new phylogeny of the Cephalaspidea (Gastropoda: Heterobranchia) based on expanded taxon sampling and gene markers.

    PubMed

    Oskars, Trond R; Bouchet, Philippe; Malaquias, Manuel António E

    2015-08-01

    The Cephalaspidea is a diverse marine clade of euthyneuran gastropods with many groups still known largely from shells or scant anatomical data. The definition of the group and the relationships between members has been hampered by the difficulty of establishing sound synapomorphies, but the advent of molecular phylogenetics is helping to change significantly this situation. Yet, because of limited taxon sampling and few genetic markers employed in previous studies, many questions about the sister relationships and monophyletic status of several families remained open. In this study 109 species of Cephalaspidea were included covering 100% of traditional family-level diversity (12 families) and 50% of all genera (33 genera). Bayesian and maximum likelihood phylogenetics analyses based on two mitochondrial (COI, 16S rRNA) and two nuclear gene markers (28S rRNA and Histone-3) were used to infer the relationships of Cephalaspidea. The monophyly of the Cephalaspidea was confirmed. The families Cylichnidae, Diaphanidae, Haminoeidae, Philinidae, and Retusidae were found non-monophyletic. This result suggests that the family level taxonomy of the Cephalaspidea warrants a profound revision and several new family and genus names are required to reflect the new phylogenetic hypothesis presented here. We propose a new classification of the Cephalaspidea including five new families (Alacuppidae, Colinatydidae, Colpodaspididae, Mnestiidae, Philinorbidae) and one new genus (Alacuppa). Two family names (Acteocinidae, Laonidae) and two genera (Laona, Philinorbis) are reinstated as valid. An additional lineage with family rank (Philinidae "Clade 4") was unravelled, but no genus and species names are available to reflect the phylogeny and formal description will take place elsewhere. PMID:25916189

  9. A Cross-Taxon Analysis of Insect-Associated Bacterial Diversity

    PubMed Central

    Jones, Ryan Thomas; Sanchez, Leticia Gonzales; Fierer, Noah

    2013-01-01

    Although it is well known that plants and animals harbor microbial symbionts that can influence host traits, the factors regulating the structure of these microbial communities often remain largely undetermined. This is particularly true for insect-associated microbial communities, as few cross-taxon comparisons have been conducted to date. To address this knowledge gap and determine how host phylogeny and ecology affect insect-associated microbial communities, we collected 137 insect specimens representing 39 species, 28 families, and 8 orders, and characterized the bacterial communities associated with each specimen via 16S rRNA gene sequencing. Bacterial taxa within the phylum Proteobacteria were dominant in nearly all insects sampled. On average, the insect-associated bacterial communities were not very diverse, with individuals typically harboring fewer than 8 bacterial phylotypes. Bacterial communities also tended to be dominated by a single phylotype; on average, the most abundant phylotype represented 54.7% of community membership. Bacterial communities were significantly more similar among closely related insects than among less-related insects, a pattern driven by within-species community similarity but detected at every level of insect taxonomy tested. Diet was a poor predictor of bacterial community composition. Individual insect species harbored remarkably unique communities: the distribution of 69.0% of bacterial phylotypes was limited to unique insect species, whereas only 5.7% of phylotypes were detected in more than five insect species. Together these results suggest that host characteristics strongly regulate the colonization and assembly of bacterial communities across insect lineages, patterns that are driven either by co-evolution between insects and their symbionts or by closely related insects sharing conserved traits that directly select for similar bacterial communities. PMID:23613815

  10. 'Candidatus Phytoplasma cirsii', a novel taxon from creeping thistle [Cirsium arvense (L.) Scop].

    PubMed

    Šafárová, Dana; Zemánek, Tomáš; Válová, Pavla; Navrátil, Milan

    2016-04-01

    Creeping thistle [Cirsium arvense (L.) Scop.] and dahlia (Dahlia sp.) plants showing typical symptoms of phytoplasma infection including yellowing, stunting, inflorescence and proliferation, were sampled; the presence of phytoplasma was confirmed by standard PCR using universal primers. RFLP analysis allowed classification of the detected phytoplasma strains CirYS, CirYS1 and DahlP within the 16SrXI group, the unique restriction profile F2nR2 fragment obtained in silico by iPhyClassifier indicated that they belong to the new 16SrXI-E subgroup. Genetic analysis of the 16S rRNA gene revealed that the studied strains shared less than 97.5% similarity with all of the previously described 'Candidatus Phytoplasma' species. The closest relatives are 'Candidatus Phytoplasma cynodontis' and 'Candidatus Phytoplasma oryzae' with 96.8% and 96.6% similarity. All strains studied bear three specific regions in the 16S rRNA gene, discriminating them from the other phytoplasma species. Phylogenetic analysis of the 16S rRNA and secA genes confirmed this specificity, as the creeping thistle and dahlia phytoplasma strains clustered in a distinguishable lineage group. The uniqueness of the genetic analysis agrees with the biological characterization of the studied phytoplasma strains, their host range, and geographical distribution. The strains only infect dicotyledonous plants in Europe, contrary to their closest relatives. Based on their unique properties, it could be concluded that the studied phytoplasma strains represent a discrete group that is proposed as a novel taxon 'Candidatus Phytoplasma cirsii', with strain CirYS as a reference strain. PMID:26849880

  11. A cross-taxon analysis of insect-associated bacterial diversity.

    PubMed

    Jones, Ryan Thomas; Sanchez, Leticia Gonzales; Fierer, Noah

    2013-01-01

    Although it is well known that plants and animals harbor microbial symbionts that can influence host traits, the factors regulating the structure of these microbial communities often remain largely undetermined. This is particularly true for insect-associated microbial communities, as few cross-taxon comparisons have been conducted to date. To address this knowledge gap and determine how host phylogeny and ecology affect insect-associated microbial communities, we collected 137 insect specimens representing 39 species, 28 families, and 8 orders, and characterized the bacterial communities associated with each specimen via 16S rRNA gene sequencing. Bacterial taxa within the phylum Proteobacteria were dominant in nearly all insects sampled. On average, the insect-associated bacterial communities were not very diverse, with individuals typically harboring fewer than 8 bacterial phylotypes. Bacterial communities also tended to be dominated by a single phylotype; on average, the most abundant phylotype represented 54.7% of community membership. Bacterial communities were significantly more similar among closely related insects than among less-related insects, a pattern driven by within-species community similarity but detected at every level of insect taxonomy tested. Diet was a poor predictor of bacterial community composition. Individual insect species harbored remarkably unique communities: the distribution of 69.0% of bacterial phylotypes was limited to unique insect species, whereas only 5.7% of phylotypes were detected in more than five insect species. Together these results suggest that host characteristics strongly regulate the colonization and assembly of bacterial communities across insect lineages, patterns that are driven either by co-evolution between insects and their symbionts or by closely related insects sharing conserved traits that directly select for similar bacterial communities.

  12. MARINE MAMMAL DISEASES: PATHOGENS AND PROCESSES

    EPA Science Inventory

    The purpose of this chapter is to provide a concise overview of the pathogens and processes that alter the health of marine mammals. Viral disease is the most common etiology of significant mortality events in marine mammals. Discussion of viral disease focuses on effects in the ...

  13. The first multituberculate mammal from India.

    PubMed

    Parmar, Varun; Prasad, Guntupalli V R; Kumar, Deepak

    2013-06-01

    Mesozoic deposits of the former Gondwanaland are depauperate in early mammals, in general, and multituberculate mammals, in particular. Until now, the oldest multituberculate mammals known from the Gondwanan continents come from the Early Cretaceous of Morocco, NW Africa. Here, we report the presence of a new multituberculate mammal, Indobaatar zofiae gen. et sp. nov., from the Lower/Middle Jurassic Kota Formation, Pranhita-Godavari valley in peninsular India. This is the first record of a multituberculate from the Mesozoic rocks of India and possibly predates the oldest known multituberculates from Gondwanan continents. The new specimen, representing an upper premolar (P(4)), compares well with the upper premolar morphology of Eobaatariinae multituberculates known from the Early Cretaceous of Mongolia, China, England, and Spain. Together with the recent findings of cimolodontan multituberculates from the Early Cretaceous of Australia and Late Cretaceous of South America, the new discovery indicates a wide temporal and spatial distribution for multituberculate mammals in the former Gondwanaland.

  14. The first multituberculate mammal from India

    NASA Astrophysics Data System (ADS)

    Parmar, Varun; Prasad, Guntupalli V. R.; Kumar, Deepak

    2013-06-01

    Mesozoic deposits of the former Gondwanaland are depauperate in early mammals, in general, and multituberculate mammals, in particular. Until now, the oldest multituberculate mammals known from the Gondwanan continents come from the Early Cretaceous of Morocco, NW Africa. Here, we report the presence of a new multituberculate mammal, Indobaatar zofiae gen. et sp. nov., from the Lower/Middle Jurassic Kota Formation, Pranhita-Godavari valley in peninsular India. This is the first record of a multituberculate from the Mesozoic rocks of India and possibly predates the oldest known multituberculates from Gondwanan continents. The new specimen, representing an upper premolar (P4), compares well with the upper premolar morphology of Eobaatariinae multituberculates known from the Early Cretaceous of Mongolia, China, England, and Spain. Together with the recent findings of cimolodontan multituberculates from the Early Cretaceous of Australia and Late Cretaceous of South America, the new discovery indicates a wide temporal and spatial distribution for multituberculate mammals in the former Gondwanaland.

  15. The inner ear of Diacodexis, the oldest artiodactyl mammal

    PubMed Central

    Orliac, M J; Benoit, J; O'Leary, M A

    2012-01-01

    We provide the first detailed description of the inner ear of the oldest artiodactyl, Diacodexis, based on a three-dimensional reconstruction extracted from computed tomography imagery of a skull of Diacodexis ilicis of earliest Wasatchian age (ca. 55 Ma). This description provides new anatomical data for the earliest artiodactyls, and reveals that the bony labyrinth of Diacodexis differs greatly from that of modern artiodactyls described so far. The bony labyrinth of Diacodexis presents a weakly coiled cochlea (720 °), a secondary common crus, a dorsal extension of the anterior semicircular canal more pronounced than that of the posterior one, and a small angle between the basal turn of the bony cochlear canal and the lateral semicircular canal. This suite of characters also occurs in basal eutherian mammals. Diacodexis strongly resembles small living tragulid ruminants in its overall body shape and hindlimb proportions. Comparison of the bony labyrinth of Diacodexis to that of the tragulid Moschiola meminna (Indian mouse deer) reveals great morphological difference in cochlear shape and semicircular canal disposition. The shape of the cochlea suggests that Diacodexis was a high-frequency hearing specialist, with a high low-frequency hearing limit (543 Hz at 60 dB). By comparison, the estimated low-frequency limit of Moschiola meminna is much lower (186.0 Hz at 60 dB). We also assess the locomotor agility of Diacodexis based on measurements of the semicircular canals. Locomotor agility estimates for Diacodexis range between 3.62 and 3.93, and suggest a degree of agility compatible with a nimble, fast running to jumping animal. These results are congruent with the postcranial functional analysis for this extinct taxon. PMID:22938073

  16. Limits to captive breeding of mammals in zoos.

    PubMed

    Alroy, John

    2015-06-01

    Captive breeding of mammals in zoos is the last hope for many of the best-known endangered species and has succeeded in saving some from certain extinction. However, the number of managed species selected is relatively small and focused on large-bodied, charismatic mammals that are not necessarily under strong threat and not always good candidates for reintroduction into the wild. Two interrelated and more fundamental questions go unanswered: have the major breeding programs succeeded at the basic level of maintaining and expanding populations, and is there room to expand them? I used published counts of births and deaths from 1970 to 2011 to quantify rates of growth of 118 captive-bred mammalian populations. These rates did not vary with body mass, contrary to strong predictions made in the ecological literature. Most of the larger managed mammalian populations expanded consistently and very few programs failed. However, growth rates have declined dramatically. The decline was predicted by changes in the ratio of the number of individuals within programs to the number of mammal populations held in major zoos. Rates decreased as the ratio of individuals in programs to populations increased. In other words, most of the programs that could exist already do exist. It therefore appears that debates over the general need for captive-breeding programs and the best selection of species are moot. Only a concerted effort could create room to manage a substantially larger number of endangered mammals. PMID:25736919

  17. A new perspective on adiposity in a naturally obese mammal

    NASA Technical Reports Server (NTRS)

    Ortiz, R. M.; Noren, D. P.; Litz, B.; Ortiz, C. L.

    2001-01-01

    Many mammals seasonally reduce body fat due to inherent periods of fasting, which is associated with decreased leptin concentrations. However, no data exist on the correlation between fat mass (FM) and circulating leptin in marine mammals, which have evolved large fat stores as part of their adaptation to periods of prolonged fasting. Therefore, FM was estimated (by tritiated water dilution), and serum leptin and cortisol were measured in 40 northern elephant seal (Mirounga angustirostris) pups early (<1 wk postweaning) and late (6-8 wk postweaning) during their natural, postweaning fast. Body mass (BM) and FM were reduced late; however, percent FM (early: 43.9 +/- 0.5, late: 45.5 +/- 0.5%) and leptin [early: 2.9 +/- 0.1 ng/ml human equivalents (HE), late: 3.0 +/- 0.1 ng/ml HE] did not change. Cortisol increased between early (9.2 +/- 0.5 microg/dl) and late (16.3 +/- 0.9 microg/dl) periods and was significantly and negatively correlated with BM (r = 0.426; P < 0.0001) and FM (r = 0.328; P = 0.003). FM and percent FM were not correlated (P > 0.10) with leptin at either period. The present study suggests that these naturally obese mammals appear to possess a novel cascade for regulating body fat that includes cortisol. The lack of a correlation between leptin and FM may reflect the different functions of fat between terrestrial and marine mammals.

  18. Limits to captive breeding of mammals in zoos.

    PubMed

    Alroy, John

    2015-06-01

    Captive breeding of mammals in zoos is the last hope for many of the best-known endangered species and has succeeded in saving some from certain extinction. However, the number of managed species selected is relatively small and focused on large-bodied, charismatic mammals that are not necessarily under strong threat and not always good candidates for reintroduction into the wild. Two interrelated and more fundamental questions go unanswered: have the major breeding programs succeeded at the basic level of maintaining and expanding populations, and is there room to expand them? I used published counts of births and deaths from 1970 to 2011 to quantify rates of growth of 118 captive-bred mammalian populations. These rates did not vary with body mass, contrary to strong predictions made in the ecological literature. Most of the larger managed mammalian populations expanded consistently and very few programs failed. However, growth rates have declined dramatically. The decline was predicted by changes in the ratio of the number of individuals within programs to the number of mammal populations held in major zoos. Rates decreased as the ratio of individuals in programs to populations increased. In other words, most of the programs that could exist already do exist. It therefore appears that debates over the general need for captive-breeding programs and the best selection of species are moot. Only a concerted effort could create room to manage a substantially larger number of endangered mammals.

  19. Spiny plants, mammal browsers, and the origin of African savannas.

    PubMed

    Charles-Dominique, Tristan; Davies, T Jonathan; Hempson, Gareth P; Bezeng, Bezeng S; Daru, Barnabas H; Kabongo, Ronny M; Maurin, Olivier; Muasya, A Muthama; van der Bank, Michelle; Bond, William J

    2016-09-20

    Savannas first began to spread across Africa during the Miocene. A major hypothesis for explaining this vegetation change is the increase in C4 grasses, promoting fire. We investigated whether mammals could also have contributed to savanna expansion by using spinescence as a marker of mammal herbivory. Looking at the present distribution of 1,852 tree species, we established that spinescence is mainly associated with two functional types of mammals: large browsers and medium-sized mixed feeders. Using a dated phylogeny for the same tree species, we found that spinescence evolved at least 55 times. The diversification of spiny plants occurred long after the evolution of Afrotherian proboscideans and hyracoids. However, it is remarkably congruent with diversification of bovids, the lineage including the antelope that predominantly browse these plants today. Our findings suggest that herbivore-adapted savannas evolved several million years before fire-maintained savannas and probably, in different environmental conditions. Spiny savannas with abundant mammal herbivores occur in drier climates and on nutrient-rich soils, whereas fire-maintained savannas occur in wetter climates on nutrient-poor soils.

  20. Spiny plants, mammal browsers, and the origin of African savannas.

    PubMed

    Charles-Dominique, Tristan; Davies, T Jonathan; Hempson, Gareth P; Bezeng, Bezeng S; Daru, Barnabas H; Kabongo, Ronny M; Maurin, Olivier; Muasya, A Muthama; van der Bank, Michelle; Bond, William J

    2016-09-20

    Savannas first began to spread across Africa during the Miocene. A major hypothesis for explaining this vegetation change is the increase in C4 grasses, promoting fire. We investigated whether mammals could also have contributed to savanna expansion by using spinescence as a marker of mammal herbivory. Looking at the present distribution of 1,852 tree species, we established that spinescence is mainly associated with two functional types of mammals: large browsers and medium-sized mixed feeders. Using a dated phylogeny for the same tree species, we found that spinescence evolved at least 55 times. The diversification of spiny plants occurred long after the evolution of Afrotherian proboscideans and hyracoids. However, it is remarkably congruent with diversification of bovids, the lineage including the antelope that predominantly browse these plants today. Our findings suggest that herbivore-adapted savannas evolved several million years before fire-maintained savannas and probably, in different environmental conditions. Spiny savannas with abundant mammal herbivores occur in drier climates and on nutrient-rich soils, whereas fire-maintained savannas occur in wetter climates on nutrient-poor soils. PMID:27601649

  1. Immunotoxic effects of environmental pollutants in marine mammals.

    PubMed

    Desforges, Jean-Pierre W; Sonne, Christian; Levin, Milton; Siebert, Ursula; De Guise, Sylvain; Dietz, Rune

    2016-01-01

    Due to their marine ecology and life-history, marine mammals accumulate some of the highest levels of environmental contaminants of all wildlife. Given the increasing prevalence and severity of diseases in marine wildlife, it is imperative to understand how pollutants affect the immune system and consequently disease susceptibility. Advancements and adaptations of analytical techniques have facilitated marine mammal immunotoxicology research. Field studies, captive-feeding experiments and in vitro laboratory studies with marine mammals have associated exposure to environmental pollutants, most notable polychlorinated biphenyls (PCBs), organochlorine pesticides and heavy metals, to alterations of both the innate and adaptive arms of immune systems, which include aspects of cellular and humoral immunity. For marine mammals, reported immunotoxicology endpoints fell into several major categories: immune tissue histopathology, haematology/circulating immune cell populations, functional immune assays (lymphocyte proliferation, phagocytosis, respiratory burst, and natural killer cell activity), immunoglobulin production, and cytokine gene expression. Lymphocyte proliferation is by far the most commonly used immune assay, with studies using different organic pollutants and metals predominantly reporting immunosuppressive effects despite the many differences in study design and animal life history. Using combined field and laboratory data, we determined effect threshold levels for suppression of lymphocyte proliferation to be between b0.001-10 ppm for PCBs, 0.002-1.3 ppm for Hg, 0.009-0.06 for MeHg, and 0.1-2.4 for cadmium in polar bears and several pinniped and cetacean species. Similarly, thresholds for suppression of phagocytosis were 0.6-1.4 and 0.08-1.9 ppm for PCBs and mercury, respectively. Although data are lacking for many important immune endpoints and mechanisms of specific immune alterations are not well understood, this review revealed a systemic suppression of

  2. Immunotoxic effects of environmental pollutants in marine mammals.

    PubMed

    Desforges, Jean-Pierre W; Sonne, Christian; Levin, Milton; Siebert, Ursula; De Guise, Sylvain; Dietz, Rune

    2016-01-01

    Due to their marine ecology and life-history, marine mammals accumulate some of the highest levels of environmental contaminants of all wildlife. Given the increasing prevalence and severity of diseases in marine wildlife, it is imperative to understand how pollutants affect the immune system and consequently disease susceptibility. Advancements and adaptations of analytical techniques have facilitated marine mammal immunotoxicology research. Field studies, captive-feeding experiments and in vitro laboratory studies with marine mammals have associated exposure to environmental pollutants, most notable polychlorinated biphenyls (PCBs), organochlorine pesticides and heavy metals, to alterations of both the innate and adaptive arms of immune systems, which include aspects of cellular and humoral immunity. For marine mammals, reported immunotoxicology endpoints fell into several major categories: immune tissue histopathology, haematology/circulating immune cell populations, functional immune assays (lymphocyte proliferation, phagocytosis, respiratory burst, and natural killer cell activity), immunoglobulin production, and cytokine gene expression. Lymphocyte proliferation is by far the most commonly used immune assay, with studies using different organic pollutants and metals predominantly reporting immunosuppressive effects despite the many differences in study design and animal life history. Using combined field and laboratory data, we determined effect threshold levels for suppression of lymphocyte proliferation to be between b0.001-10 ppm for PCBs, 0.002-1.3 ppm for Hg, 0.009-0.06 for MeHg, and 0.1-2.4 for cadmium in polar bears and several pinniped and cetacean species. Similarly, thresholds for suppression of phagocytosis were 0.6-1.4 and 0.08-1.9 ppm for PCBs and mercury, respectively. Although data are lacking for many important immune endpoints and mechanisms of specific immune alterations are not well understood, this review revealed a systemic suppression of

  3. Multiple Continental Radiations and Correlates of Diversification in Lupinus (Leguminosae): Testing for Key Innovation with Incomplete Taxon Sampling

    PubMed Central

    Drummond, Christopher S.; Eastwood, Ruth J.; Miotto, Silvia T. S.; Hughes, Colin E.

    2012-01-01

    Replicate radiations provide powerful comparative systems to address questions about the interplay between opportunity and innovation in driving episodes of diversification and the factors limiting their subsequent progression. However, such systems have been rarely documented at intercontinental scales. Here, we evaluate the hypothesis of multiple radiations in the genus Lupinus (Leguminosae), which exhibits some of the highest known rates of net diversification in plants. Given that incomplete taxon sampling, background extinction, and lineage-specific variation in diversification rates can confound macroevolutionary inferences regarding the timing and mechanisms of cladogenesis, we used Bayesian relaxed clock phylogenetic analyses as well as MEDUSA and BiSSE birth–death likelihood models of diversification, to evaluate the evolutionary patterns of lineage accumulation in Lupinus. We identified 3 significant shifts to increased rates of net diversification (r) relative to background levels in the genus (r = 0.18–0.48 lineages/myr). The primary shift occurred approximately 4.6 Ma (r = 0.48–1.76) in the montane regions of western North America, followed by a secondary shift approximately 2.7 Ma (r = 0.89–3.33) associated with range expansion and diversification of allopatrically distributed sister clades in the Mexican highlands and Andes. We also recovered evidence for a third independent shift approximately 6.5 Ma at the base of a lower elevation eastern South American grassland and campo rupestre clade (r = 0.36–1.33). Bayesian ancestral state reconstructions and BiSSE likelihood analyses of correlated diversification indicated that increased rates of speciation are strongly associated with the derived evolution of perennial life history and invasion of montane ecosystems. Although we currently lack hard evidence for “replicate adaptive radiations” in the sense of convergent morphological and ecological trajectories among species in different

  4. Sperm competition and the evolution of sperm design in mammals

    PubMed Central

    2011-01-01

    Background The influence of sperm competition upon sperm size has been a controversial issue during the last 20 years which remains unresolved for mammals. The hypothesis that, when ejaculates compete with rival males, an increase in sperm size would make sperm more competitive because it would increase sperm swimming speed, has generated contradictory results from both theoretical and empirical studies. In addition, the debate has extended to which sperm components should increase in size: the midpiece to accommodate more mitochondria and produce more energy to fuel motility, or the principal piece to generate greater propulsion forces. Results In this study we examined the influence of sperm competition upon sperm design in mammals using a much larger data set (226 species) than in previous analyses, and we corrected for phylogenetic effects by using a more complete and resolved phylogeny, and more robust phylogenetic control methods. Our results show that, as sperm competition increases, all sperm components increase in an integrated manner and sperm heads become more elongated. The increase in sperm length was found to be associated with enhanced swimming velocity, an adaptive trait under sperm competition. Conclusions We conclude that sperm competition has played an important role in the evolution of sperm design in mammals, and discuss why previous studies have failed to detect it. PMID:21232104

  5. NITROGEN OUTPUTS OF SMALL MAMMALS FROM FECAL AND URINE DEPOSITION: IMPLICATIONS FOR NITROGEN CYCLING

    EPA Science Inventory

    The contribution of small mammals in nitrogen cycling is poorly understood and could have reverberations back to the producer community by maintaining or even magnifying increased nitrogen availability. Our objective was to model nitrogen outputs (deposition of feces and urine) ...

  6. Implications of invasion by Juniperus virginiana on small mammals in the southern Great Plains

    USGS Publications Warehouse

    Horncastle, V.J.; Hellgren, E.C.; Mayer, P.M.; Ganguli, A.C.; Engle, David M.; Leslie, David M.

    2005-01-01

    Changes in landscape cover in the Great Plains are resulting from the range expansion and invasion of eastern red cedar (Juniperus virginiana). By altering the landscape and local vegetation, red cedar is changing the structure and function of habitat for small mammals. We examined effects of invasion by eastern red cedar on small mammals in 3 plant communities (tallgrass prairie, old field, and cross-timbers forest) in the cross-timbers ecoregion in Oklahoma. We sampled small mammals seasonally from May 2001 to August 2002 by using Sherman live traps and mark-recapture techniques on 3.24-ha, 450-trap grids in each plant community. We sampled vegetation in two hundred twenty-five 12 x 12-m cells within each grid. The structure of the small-mammal community differed among the 3 habitat types, with higher species diversity and richness in the tallgrass-prairie and old-field sites. Overall, the small-mammal community shifted along a gradient of increasing eastern red cedar. In the old-field and tallgrass-prairie plots, occurrence of grassland mammals decreased with increasing red cedar, whereas only 1 woodland mammal species increased. In the cross-timbers forest site, percent woody cover (<1 m in height), rather than cover of red cedar, was the most important factor affecting woodland mammal species. Examination of our data suggests that an increase in overstory cover from 0% to 30% red cedar can change a species-rich prairie community to a depauperate community dominated by 1 species, Peromyscus leucopus. Losses in species diversity and changes in mammal distribution paralleled those seen in avian communities invaded by eastern red cedar. Our results highlight ecological effects of invasion by eastern red cedar on diversity and function at multiple trophic levels. ?? 2005 American Society of Mammalogists.

  7. Snake mitochondrial genomes: phylogenetic relationships and implications of extended taxon sampling for interpretations of mitogenomic evolution

    PubMed Central

    2010-01-01

    alethinophidians. Conclusions Mitochondrial gene sequence data alone may not be able to robustly resolve basal divergences among alethinophidian snakes. Taxon sampling plays an important role in identifying mitogenomic evolutionary events within snakes, and in testing hypotheses explaining their origin. Dramatic rate shifts in mitogenomic evolution occur within Scolecophidia as well as Alethinophidia, thus falsifying the hypothesis that these shifts in snakes are associated exclusively with evolution of a non-burrowing lifestyle, macrostomatan feeding ecology and/or duplication of the control region, both restricted to alethinophidians among living snakes. PMID:20055998

  8. Asymmetric hybridization in Rhododendron agastum: a hybrid taxon comprising mainly F1s in Yunnan, China

    PubMed Central

    Zha, Hong-Guang; Milne, Richard I.; Sun, Hang

    2010-01-01

    Background and Aims Rhododendron (Ericaceae) is a large woody genus in which hybridization is thought to play an important role in evolution and speciation, particularly in the Sino-Himalaya region where many interfertile species often occur sympatrically. Rhododendron agastum, a putative hybrid species, occurs in China, western Yunnan Province, in mixed populations with R. irroratum and R. delavayi. Methods Material of these taxa from two sites 400 km apart (ZhuJianYuan, ZJY and HuaDianBa, HDB) was examined using cpDNA and internal transcribed spacer (ITS) sequences, and amplified fragment length polymorphism (AFLP) loci, to test the possibility that R. agastum was in fact a hybrid between two of the other species. Chloroplast trnL-F and trnS-trnG sequences together distinguished R. irroratum, R. delavayi and some material of R. decorum, which is also considered a putative parent of R. agastum. Key Results All 14 R. agastum plants from the HDB site had the delavayi cpDNA haplotype, whereas at the ZJY site 17 R. agastum plants had this haplotype and four had the R. irroratum haplotype. R. irroratum and R. delavayi are distinguished by five unequivocal point mutations in their ITS sequences; every R. agastum accession had an additive pattern (double peaks) at each of these sites. Data from AFLP loci were acquired for between ten and 21 plants of each taxon from each site, and were analysed using a Bayesian approach implemented by the program NewHybrids. The program confirmed the identity of all accessions of R. delavayi, and all R. irroratum except one, which was probably a backcross. All R. agastum from HDB and 19 of 21 from ZJY were classified as F1 hybrids; the other two could not be assigned a class. Conclusions Rhododendron agastum represents populations of hybrids between R. irroratum and R. delavayi, which comprise mostly or only F1s, at the two sites examined. The sites differ in that at HDB there was no detected variation in cpDNA type or hybrid class

  9. Reconsidering the evolution of brain, cognition, and behavior in birds and mammals

    PubMed Central

    Willemet, Romain

    2013-01-01

    Despite decades of research, some of the most basic issues concerning the extraordinarily complex brains and behavior of birds and mammals, such as the factors responsible for the diversity of brain size and composition, are still unclear. This is partly due to a number of conceptual and methodological issues. Determining species and group differences in brain composition requires accounting for the presence of taxon-cerebrotypes and the use of precise statistical methods. The role of allometry in determining brain variables should be revised. In particular, bird and mammalian brains appear to have evolved in response to a variety of selective pressures influencing both brain size and composition. “Brain” and “cognition” are indeed meta-variables, made up of the variables that are ecologically relevant and evolutionarily selected. External indicators of species differences in cognition and behavior are limited by the complexity of these differences. Indeed, behavioral differences between species and individuals are caused by cognitive and affective components. Although intra-species variability forms the basis of species evolution, some of the mechanisms underlying individual differences in brain and behavior appear to differ from those between species. While many issues have persisted over the years because of a lack of appropriate data or methods to test them; several fallacies, particularly those related to the human brain, reflect scientists' preconceptions. The theoretical framework on the evolution of brain, cognition, and behavior in birds and mammals should be reconsidered with these biases in mind. PMID:23847570

  10. The predictability of extinction: biological and external correlates of decline in mammals

    PubMed Central

    Cardillo, Marcel; Mace, Georgina M; Gittleman, John L; Jones, Kate E; Bielby, Jon; Purvis, Andy

    2008-01-01

    Extinction risk varies among species, and comparative analyses can help clarify the causes of this variation. Here we present a phylogenetic comparative analysis of species-level extinction risk across nearly the whole of the class Mammalia. Our aims were to examine systematically the degree to which general predictors of extinction risk can be identified, and to investigate the relative importance of different types of predictors (life history, ecological, human impact and environmental) in determining extinction risk. A single global model explained 27.3% of variation in mammal extinction risk, but explanatory power was lower for region-specific models (median R2=0.248) and usually higher for taxon-specific models (median R2=0.383). Geographical range size, human population density and latitude were the most consistently significant predictors of extinction risk, but otherwise there was little evidence for general, prescriptive indicators of high extinction risk across mammals. Our results therefore support the view that comparative models of relatively narrow taxonomic scope are likely to be the most precise. PMID:18367443

  11. The origin and early radiation of the therapsid mammal-like reptiles: a palaeobiological hypothesis.

    PubMed

    Kemp, T S

    2006-07-01

    The replacement of the basal synapsid pelycosaurs by the more 'mammal-like' therapsids in the Permian was an important event in the history of tetrapods because it initiated the eventual transition to the mammals. It is also an example of taxon replacement in the fossil record that is unusually amenable to explanation, based on a combination of analysis of the biological significance of the inferred character changes, with the stratigraphic, palaeogeographic and palaeoecological circumstances of the time. An hypothesis is presented in which the origin of the therapsids resulted from a correlated progression of character evolution leading to higher levels of metabolic activity and homeostatic regulation of the body. It was a response to the availability of a seasonally arid, savanna-like biome. The subsequent explosive radiation of therapsids was associated with habitat expansion made possible by the Mid-Permian development of geographical continuity between that biome and the temperate biomes. The final extinction of the pelycosaurs was a case of incumbent replacement by the new therapsid lineages. PMID:16780524

  12. Habitat patterns in a small mammal community

    SciTech Connect

    Kitchings, J.T.; Levy, D.J.

    1981-11-01

    Microhabitat relationships between four sympatric small mammal species (Peromyscus leucopus, Ochrotomys nuttalli, Blarina brevicauda, and Tamias striatus) were examined to determine if their discriminant analysis of small mammal habitat represented a unique habitat utilization pattern for a specific small mammal community. The authors concluded that habitat is only one of many dimensions to be considered when studying the interactions of sympatric species. Reproductive strategy, activity patterns, and other factors make up the n-dimensional hyperspace of an animal's niche. Thus differences in habitat usage alone cannot be used to determine niche overlap and competition between species. (JMT)

  13. Marine mammals from the Miocene of Panama

    NASA Astrophysics Data System (ADS)

    Uhen, Mark D.; Coates, Anthony G.; Jaramillo, Carlos A.; Montes, Camilo; Pimiento, Catalina; Rincon, Aldo; Strong, Nikki; Velez-Juarbe, Jorge

    2010-12-01

    Panama has produced an abundance of Neogene marine fossils both invertebrate (mollusks, corals, microfossils etc.) and vertebrate (fish, land mammals etc.), but marine mammals have not been previously reported. Here we describe a cetacean thoracic vertebra from the late Miocene Tobabe Formation, a partial cetacean rib from the late Miocene Gatun Formation, and a sirenian caudal vertebra and rib fragments from the early Miocene Culebra Formation. These finds suggest that Central America may yet provide additional fossil marine mammal specimens that will help us to understand the evolution, and particularly the biogeography of these groups.

  14. Running and Breathing in Mammals

    NASA Astrophysics Data System (ADS)

    Bramble, Dennis M.; Carrier, David R.

    1983-01-01

    Mechanical constraints appear to require that locomotion and breathing be synchronized in running mammals. Phase locking of limb and respiratory frequency has now been recorded during treadmill running in jackrabbits and during locomotion on solid ground in dogs, horses, and humans. Quadrupedal species normally synchronize the locomotor and respiratory cycles at a constant ratio of 1:1 (strides per breath) in both the trot and gallop. Human runners differ from quadrupeds in that while running they employ several phase-locked patterns (4:1, 3:1, 2:1, 1:1, 5:2, and 3:2), although a 2:1 coupling ratio appears to be favored. Even though the evolution of bipedal gait has reduced the mechanical constraints on respiration in man, thereby permitting greater flexibility in breathing pattern, it has seemingly not eliminated the need for the synchronization of respiration and body motion during sustained running. Flying birds have independently achieved phase-locked locomotor and respiratory cycles. This hints that strict locomotor-respiratory coupling may be a vital factor in the sustained aerobic exercise of endothermic vertebrates, especially those in which the stresses of locomotion tend to deform the thoracic complex.

  15. Passive electroreception in aquatic mammals.

    PubMed

    Czech-Damal, Nicole U; Dehnhardt, Guido; Manger, Paul; Hanke, Wolf

    2013-06-01

    Passive electroreception is a sensory modality in many aquatic vertebrates, predominantly fishes. Using passive electroreception, the animal can detect and analyze electric fields in its environment. Most electric fields in the environment are of biogenic origin, often produced by prey items. These electric fields can be relatively strong and can be a highly valuable source of information for a predator, as underlined by the fact that electroreception has evolved multiple times independently. The only mammals that possess electroreception are the platypus (Ornithorhynchus anatinus) and the echidnas (Tachyglossidae) from the monotreme order, and, recently discovered, the Guiana dolphin (Sotalia guianensis) from the cetacean order. Here we review the morphology, function and origin of the electroreceptors in the two aquatic species, the platypus and the Guiana dolphin. The morphology shows certain similarities, also similar to ampullary electroreceptors in fishes, that provide cues for the search for electroreceptors in more vertebrate and invertebrate species. The function of these organs appears to be very similar. Both species search for prey animals in low-visibility conditions or while digging in the substrate, and sensory thresholds are within one order of magnitude. The electroreceptors in both species are innervated by the trigeminal nerve. The origin of the accessory structures, however, is completely different; electroreceptors in the platypus have developed from skin glands, in the Guiana dolphin, from the vibrissal system. PMID:23187861

  16. Mapping biodiversity value worldwide: combining higher-taxon richness from different groups

    PubMed Central

    Williams, P. H.; Gaston, K. J.; Humphries, C. J.

    1997-01-01

    Maps of large-scale biodiversity are urgently needed to guide conservation, and yet complete enumeration of organisms is impractical at present. One indirect approach is to measure richness at higher taxonomic ranks, such as families. The difficulty is how to combine information from different groups on numbers of higher taxa, when these taxa may in effect have been defined in different ways, particularly for more distantly related major groups. In this paper, the regional family richness of terrestrial and freshwater seed plants, amphibians, reptiles and mammals is mapped worldwide by combining: (i) absolute family richness; (ii) proportional family richness; and (iii) proportional family richness weighted for the total species richness in each major group. The assumptions of the three methods and their effects on the results are discussed, although for these data the broad pattern is surprisingly robust with respect to the method of combination. Scores from each of the methods of combining families are used to rank the top five richness hotspots and complementary areas, and hotspots of endemism are mapped by unweighted combination of range-size rarity scores.

  17. Central control of thermogenesis in mammals

    PubMed Central

    Morrison, Shaun F.; Nakamura, Kazuhiro; Madden, Christopher J.

    2008-01-01

    Thermogenesis, the production of heat energy, is an essential component of the homeostatic repertoire to maintain body temperature in mammals and birds during the challenge of low environmental temperature and plays a key role in elevating body temperature during the febrile response to infection. The primary sources of neurally regulated metabolic heat production are mitochondrial oxidation in brown adipose tissue, increases in heart rate and shivering in skeletal muscle. Thermogenesis is regulated in each of these tissues by parallel networks in the central nervous system, which respond to feedforward afferent signals from cutaneous and core body thermoreceptors and to feedback signals from brain thermosensitive neurons to activate the appropriate sympathetic and somatic efferents. This review summarizes the research leading to a model of the feedforward reflex pathway through which environmental cold stimulates thermogenesis and discusses the influence on this thermoregulatory network of the pyrogenic mediator, prostaglandin E2, to increase body temperature. The cold thermal afferent circuit from cutaneous thermal receptors ascends via second-order thermosensory neurons in the dorsal horn of the spinal cord to activate neurons in the lateral parabrachial nucleus, which drive GABAergic interneurons in the preoptic area to inhibit warm-sensitive, inhibitory output neurons of the preoptic area. The resulting disinhibition of thermogenesis-promoting neurons in the dorsomedial hypothalamus and possibly of sympathetic and somatic premotor neurons in the rostral ventromedial medulla, including the raphe pallidus, activates excitatory inputs to spinal sympathetic and somatic motor circuits to drive thermogenesis. PMID:18469069

  18. Impacts of roads and hunting on central African rainforest mammals.

    PubMed

    Laurance, William E; Croes, Barbara M; Tchignoumba, Landry; Lahm, Sally A; Alonso, Alfonso; Lee, Michelle E; Campbell, Patrick; Ondzeano, Claude

    2006-08-01

    Road expansion and associated increases in bunting pressure are a rapidly growing threat to African tropical wildlife. In the rainforests of southern Gabon, we compared abundances of larger (>1 kg) mammal species at varying distances from forest roads and between hunted and unhunted treatments (comparing a 130-km2 oil concession that was almost entirely protected from bunting with nearby areas outside the concession that had moderate hunting pressure). At each of 12 study sites that were evenly divided between hunted and unhunted areas, we established standardized 1-km transects at five distances (50, 300, 600, 900, and 1200 m) from an unpaved road, and then repeatedly surveyed mammals during the 2004 dry and wet seasons. Hunting had the greatest impact on duikers (Cephalophus spp.), forest buffalo (Syncerus caffer nanus), and red river hogs (Potamochoerus porcus), which declined in abundance outside the oil concession, and lesser effects on lowland gorillas (Gorilla gorilla gorilla) and carnivores. Roads depressed abundances of duikers, sitatungas (Tragelaphus spekei gratus), and forest elephants (Loxondonta africana cyclotis), with avoidance of roads being stronger outside than inside the concession. Five monkey species showed little response to roads or hunting, whereas some rodents and pangolins increased in abundance outside the concession, possibly in response to greater forest disturbance. Our findings suggest that even moderate hunting pressure can markedly alter the structure of mammal communities in central Africa. Roads had the greatest impacts on large and small ungulates, with the magnitude of road avoidance increasing with local hunting pressure. PMID:16922241

  19. A Mesozoic gliding mammal from northeastern China.

    PubMed

    Meng, Jin; Hu, Yaoming; Wang, Yuanqing; Wang, Xiaolin; Li, Chuankui

    2006-12-14

    Gliding flight has independently evolved many times in vertebrates. Direct evidence of gliding is rare in fossil records and is unknown in mammals from the Mesozoic era. Here we report a new Mesozoic mammal from Inner Mongolia, China, that represents a previously unknown group characterized by a highly specialized insectivorous dentition and a sizable patagium (flying membrane) for gliding flight. The patagium is covered with dense hair and supported by an elongated tail and limbs; the latter also bear many features adapted for arboreal life. This discovery extends the earliest record of gliding flight for mammals to at least 70 million years earlier in geological history, and demonstrates that early mammals were diverse in their locomotor strategies and lifestyles; they had experimented with an aerial habit at about the same time as, if not earlier than, when birds endeavoured to exploit the sky.

  20. [Examination of cause of failure to taxon-specific DNA was not detected from bifun (rice vermicelli) using processing model experiment].

    PubMed

    Takahashi, Kunihiko; Ishii, Rie; Matsumoto, Ryuji; Horie, Masakazu

    2010-01-01

    In the inspection of genetically modified rice, rice taxon-specific DNA could not be detected in processed rice food (bifun: rice vermicelli). The effects of using PCR the ratio of rice powder content and temperature of processing on the detection of taxon-specific DNA were examined by means of processing model experiments using cornstarch with 0, 2, 5, 10% rice powder by weight. Cornstarch and rice powder were blended with water and subjected to heating, steam-treatment, and autoclaving. The rice taxon-specific DNA was detectable in 2% rice powder following heat and steam treatments. After autoclaving, rice taxon-specific DNA was detected only in the 10% rice powder product. In the processing model experiment using rice powder, it was found that autoclaving caused severe DNA degradation.

  1. Advances in exotic mammal clinical therapeutics.

    PubMed

    Hawkins, Michelle G

    2015-05-01

    It is important that veterinarians treating exotic companion mammals stay abreast of the latest developments relating to medications and drug delivery approaches for safety, efficacy and welfare issues. Sustained release formulations of commonly used drugs as well as newer routes for administration of therapeutic agents allow the veterinarian treating exotic companion mammals to reduce the stress associated with drug administration. Interactions can occur between vehicle and drugs when formulations are compounded, therefore research studies are warranted regarding potential problems associated with these formulations.

  2. Video Otoscopy in Exotic Companion Mammals.

    PubMed

    Jekl, Vladimir; Hauptman, Karel; Knotek, Zdenek

    2015-09-01

    Ear disease is a common disorder seen in exotic companion mammals, especially in ferrets, rabbits, and rats. This article describes patient preparation, equipment, and video otoscopy technique in exotic companion mammals. This noninvasive technique facilitates accurate diagnosis of diseases affecting the external ear canal or middle ear. Moreover, therapeutic otoscopic evaluation of the external ear facilitates foreign body removal, external ear canal flushing, intralesional drug administration, myringotomy, and middle ear cavity flushing.

  3. Negative effects of an exotic grass invasion on small-mammal communities.

    PubMed

    Freeman, Eric D; Sharp, Tiffanny R; Larsen, Randy T; Knight, Robert N; Slater, Steven J; McMillan, Brock R

    2014-01-01

    Exotic invasive species can directly and indirectly influence natural ecological communities. Cheatgrass (Bromus tectorum) is non-native to the western United States and has invaded large areas of the Great Basin. Changes to the structure and composition of plant communities invaded by cheatgrass likely have effects at higher trophic levels. As a keystone guild in North American deserts, granivorous small mammals drive and maintain plant diversity. Our objective was to assess potential effects of invasion by cheatgrass on small-mammal communities. We sampled small-mammal and plant communities at 70 sites (Great Basin, Utah). We assessed abundance and diversity of the small-mammal community, diversity of the plant community, and the percentage of cheatgrass cover and shrub species. Abundance and diversity of the small-mammal community decreased with increasing abundance of cheatgrass. Similarly, cover of cheatgrass remained a significant predictor of small-mammal abundance even after accounting for the loss of the shrub layer and plant diversity, suggesting that there are direct and indirect effects of cheatgrass. The change in the small-mammal communities associated with invasion of cheatgrass likely has effects through higher and lower trophic levels and has the potential to cause major changes in ecosystem structure and function.

  4. Deconstructing mammal dispersals and faunal dynamics in SW Europe during the Quaternary

    NASA Astrophysics Data System (ADS)

    Palombo, Maria Rita

    2014-07-01

    This research aims to investigate the relationships between climate change and faunal dynamics in south-west Europe, disentangling the asynchronous and diachronous dispersal bioevents of large mammals across geographical and ecological boundaries, analysing biodiversity and its changes through time. The analysis of local versus regional biological dynamics may shed new light on whether turnovers and ecological and evolutionary changes developed because of global climate changes and related phenomena, or because of intrinsic biological factors. The SW European Quaternary fossil record is particularly suitable for studying the role of climate change at local and regional levels because of the complex physiographic and climatic heterogeneity of the study area, the presence of important geographical/ecological barriers and the complex history of invasions of species of varying geographical origin and provenance. The data base consists of taxonomically revised lists of large mammal species from selected SW European local faunal assemblages ranging in age from the Early to the late Middle Pleistocene (middle Villafranchian to early Aurelian European Land Mammal Ages). The new biochronological scheme proposed here allows for the comparison of local turnovers and biodiversity trends, yielding a better understanding of the action of geographical/ecological barriers that either prevented the range of some taxa from reaching some regions or caused delays in the dispersal of a taxon in some territories. The results obtained provide evidence that major environmental perturbations, triggering dispersal events and removing keystone species, modified the structure of the pre-existing mammalian faunas, merging previously independently-evolved taxa into new palaeo-communities. The coupled action of climatic changes and internal biotic dynamics thus caused the Quaternary SW European faunal complexes to significantly restructure. Diachroneity in local turnover across the study area

  5. Species longevity in North American fossil mammals.

    PubMed

    Prothero, Donald R

    2014-08-01

    Species longevity in the fossil record is related to many paleoecological variables and is important to macroevolutionary studies, yet there are very few reliable data on average species durations in Cenozoic fossil mammals. Many of the online databases (such as the Paleobiology Database) use only genera of North American Cenozoic mammals and there are severe problems because key groups (e.g. camels, oreodonts, pronghorns and proboscideans) have no reliable updated taxonomy, with many invalid genera and species and/or many undescribed genera and species. Most of the published datasets yield species duration estimates of approximately 2.3-4.3 Myr for larger mammals, with small mammals tending to have shorter species durations. My own compilation of all the valid species durations in families with updated taxonomy (39 families, containing 431 genera and 998 species, averaging 2.3 species per genus) yields a mean duration of 3.21 Myr for larger mammals. This breaks down to 4.10-4.39 Myr for artiodactyls, 3.14-3.31 Myr for perissodactyls and 2.63-2.95 Myr for carnivorous mammals (carnivorans plus creodonts). These averages are based on a much larger, more robust dataset than most previous estimates, so they should be more reliable for any studies that need species longevity to be accurately estimated.

  6. A Jurassic mammal from South America.

    PubMed

    Rauhut, Oliver W M; Martin, Thomas; Ortiz-Jaureguizar, Edgardo; Puerta, Pablo

    2002-03-14

    The Jurassic period is an important stage in early mammalian evolution, as it saw the first diversification of this group, leading to the stem lineages of monotremes and modern therian mammals. However, the fossil record of Jurassic mammals is extremely poor, particularly in the southern continents. Jurassic mammals from Gondwanaland are so far only known from Tanzania and Madagascar, and from trackway evidence from Argentina. Here we report a Jurassic mammal represented by a dentary, which is the first, to our knowledge, from South America. The tiny fossil from the Middle to Late Jurassic of Patagonia is a representative of the recently termed Australosphenida, a group of mammals from Gondwanaland that evolved tribosphenic molars convergently to the Northern Hemisphere Tribosphenida, and probably gave rise to the monotremes. Together with other mammalian evidence from the Southern Hemisphere, the discovery of this new mammal indicates that the Australosphenida had diversified and were widespread in Gondwanaland well before the end of the Jurassic, and that mammalian faunas from the Southern Hemisphere already showed a marked distinction from their northern counterparts by the Middle to Late Jurassic. PMID:11894091

  7. A Jurassic mammal from South America.

    PubMed

    Rauhut, Oliver W M; Martin, Thomas; Ortiz-Jaureguizar, Edgardo; Puerta, Pablo

    2002-03-14

    The Jurassic period is an important stage in early mammalian evolution, as it saw the first diversification of this group, leading to the stem lineages of monotremes and modern therian mammals. However, the fossil record of Jurassic mammals is extremely poor, particularly in the southern continents. Jurassic mammals from Gondwanaland are so far only known from Tanzania and Madagascar, and from trackway evidence from Argentina. Here we report a Jurassic mammal represented by a dentary, which is the first, to our knowledge, from South America. The tiny fossil from the Middle to Late Jurassic of Patagonia is a representative of the recently termed Australosphenida, a group of mammals from Gondwanaland that evolved tribosphenic molars convergently to the Northern Hemisphere Tribosphenida, and probably gave rise to the monotremes. Together with other mammalian evidence from the Southern Hemisphere, the discovery of this new mammal indicates that the Australosphenida had diversified and were widespread in Gondwanaland well before the end of the Jurassic, and that mammalian faunas from the Southern Hemisphere already showed a marked distinction from their northern counterparts by the Middle to Late Jurassic.

  8. Climate change and seasonal reproduction in mammals.

    PubMed

    Bronson, F H

    2009-11-27

    Seasonal reproduction is common among mammals at all latitudes, even in the deep tropics. This paper (i) discusses the neuroendocrine pathways via which foraging conditions and predictive cues such as photoperiod enforce seasonality, (ii) considers the kinds of seasonal challenges mammals actually face in natural habitats, and (iii) uses the information thus generated to suggest how seasonal reproduction might be influenced by global climate change. Food availability and ambient temperature determine energy balance, and variation in energy balance is the ultimate cause of seasonal breeding in all mammals and the proximate cause in many. Photoperiodic cueing is common among long-lived mammals from the highest latitudes down to the mid-tropics. It is much less common in shorter lived mammals at all latitudes. An unknown predictive cue triggers reproduction in some desert and dry grassland species when it rains. The available information suggests that as our climate changes the small rodents of the world may adapt rather easily but the longer lived mammals whose reproduction is regulated by photoperiod may not do so well. A major gap in our knowledge concerns the tropics; that is where most species live and where we have the least understanding of how reproduction is regulated by environmental factors.

  9. Disentangling effects of abiotic factors and biotic interactions on cross-taxon congruence in species turnover patterns of plants, moths and beetles.

    PubMed

    Duan, Meichun; Liu, Yunhui; Yu, Zhenrong; Baudry, Jacques; Li, Liangtao; Wang, Changliu; Axmacher, Jan C

    2016-01-01

    High cross-taxon congruence in species diversity patterns is essential for the use of surrogate taxa in biodiversity conservation, but presence and strength of congruence in species turnover patterns, and the relative contributions of abiotic environmental factors and biotic interaction towards this congruence, remain poorly understood. In our study, we used variation partitioning in multiple regressions to quantify cross-taxon congruence in community dissimilarities of vascular plants, geometrid and arciinid moths and carabid beetles, subsequently investigating their respective underpinning by abiotic factors and biotic interactions. Significant cross-taxon congruence observed across all taxon pairs was linked to their similar responses towards elevation change. Changes in the vegetation composition were closely linked to carabid turnover, with vegetation structure and associated microclimatic conditions proposed causes of this link. In contrast, moth assemblages appeared to be dominated by generalist species whose turnover was weakly associated with vegetation changes. Overall, abiotic factors exerted a stronger influence on cross-taxon congruence across our study sites than biotic interactions. The weak congruence in turnover observed particularly between plants and moths highlights the importance of multi-taxon approaches based on groupings of taxa with similar turnovers, rather than the use of single surrogate taxa or environmental proxies, in biodiversity assessments. PMID:27032533

  10. Disentangling effects of abiotic factors and biotic interactions on cross-taxon congruence in species turnover patterns of plants, moths and beetles.

    PubMed

    Duan, Meichun; Liu, Yunhui; Yu, Zhenrong; Baudry, Jacques; Li, Liangtao; Wang, Changliu; Axmacher, Jan C

    2016-01-01

    High cross-taxon congruence in species diversity patterns is essential for the use of surrogate taxa in biodiversity conservation, but presence and strength of congruence in species turnover patterns, and the relative contributions of abiotic environmental factors and biotic interaction towards this congruence, remain poorly understood. In our study, we used variation partitioning in multiple regressions to quantify cross-taxon congruence in community dissimilarities of vascular plants, geometrid and arciinid moths and carabid beetles, subsequently investigating their respective underpinning by abiotic factors and biotic interactions. Significant cross-taxon congruence observed across all taxon pairs was linked to their similar responses towards elevation change. Changes in the vegetation composition were closely linked to carabid turnover, with vegetation structure and associated microclimatic conditions proposed causes of this link. In contrast, moth assemblages appeared to be dominated by generalist species whose turnover was weakly associated with vegetation changes. Overall, abiotic factors exerted a stronger influence on cross-taxon congruence across our study sites than biotic interactions. The weak congruence in turnover observed particularly between plants and moths highlights the importance of multi-taxon approaches based on groupings of taxa with similar turnovers, rather than the use of single surrogate taxa or environmental proxies, in biodiversity assessments.

  11. Disentangling effects of abiotic factors and biotic interactions on cross-taxon congruence in species turnover patterns of plants, moths and beetles

    PubMed Central

    Duan, Meichun; Liu, Yunhui; Yu, Zhenrong; Baudry, Jacques; Li, Liangtao; Wang, Changliu; Axmacher, Jan C.

    2016-01-01

    High cross-taxon congruence in species diversity patterns is essential for the use of surrogate taxa in biodiversity conservation, but presence and strength of congruence in species turnover patterns, and the relative contributions of abiotic environmental factors and biotic interaction towards this congruence, remain poorly understood. In our study, we used variation partitioning in multiple regressions to quantify cross-taxon congruence in community dissimilarities of vascular plants, geometrid and arciinid moths and carabid beetles, subsequently investigating their respective underpinning by abiotic factors and biotic interactions. Significant cross-taxon congruence observed across all taxon pairs was linked to their similar responses towards elevation change. Changes in the vegetation composition were closely linked to carabid turnover, with vegetation structure and associated microclimatic conditions proposed causes of this link. In contrast, moth assemblages appeared to be dominated by generalist species whose turnover was weakly associated with vegetation changes. Overall, abiotic factors exerted a stronger influence on cross-taxon congruence across our study sites than biotic interactions. The weak congruence in turnover observed particularly between plants and moths highlights the importance of multi-taxon approaches based on groupings of taxa with similar turnovers, rather than the use of single surrogate taxa or environmental proxies, in biodiversity assessments. PMID:27032533

  12. 76 FR 30309 - Marine Mammals; File No. 16087

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-25

    ... the Federal Register (76 FR 13603) that a request for a permit to conduct research on marine mammals... National Oceanic and Atmospheric Administration RIN 0648-XA292 Marine Mammals; File No. 16087 AGENCY... National Marine Mammal Laboratory, Seattle, WA, to conduct research on marine mammals. ADDRESSES:...

  13. 50 CFR 216.83 - Importation of birds or mammals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 10 2014-10-01 2014-10-01 false Importation of birds or mammals. 216.83 Section 216.83 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC... MAMMALS Pribilof Islands Administration § 216.83 Importation of birds or mammals. No mammals or...

  14. 50 CFR 216.83 - Importation of birds or mammals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Importation of birds or mammals. 216.83 Section 216.83 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC... MAMMALS Pribilof Islands Administration § 216.83 Importation of birds or mammals. No mammals or...

  15. 50 CFR 216.83 - Importation of birds or mammals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 10 2013-10-01 2013-10-01 false Importation of birds or mammals. 216.83 Section 216.83 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC... MAMMALS Pribilof Islands Administration § 216.83 Importation of birds or mammals. No mammals or...

  16. The evolution of acoustic size exaggeration in terrestrial mammals.

    PubMed

    Charlton, Benjamin D; Reby, David

    2016-01-01

    Recent studies have revealed that some mammals possess adaptations that enable them to produce vocal signals with much lower fundamental frequency (F0) and formant frequency spacing (ΔF) than expected for their size. Although these adaptations are assumed to reflect selection pressures for males to lower frequency components and exaggerate body size in reproductive contexts, this hypothesis has not been tested across a broad range of species. Here we show that male terrestrial mammals produce vocal signals with lower ΔF (but not F0) than expected for their size in mating systems with greater sexual size dimorphism. We also reveal that males produce calls with higher than expected F0 and ΔF in species with increased sperm competition. This investigation confirms that sexual selection favours the use of ΔF as an acoustic size exaggerator and supports the notion of an evolutionary trade-off between pre-copulatory signalling displays and sperm production. PMID:27598835

  17. Wet mammals shake at tuned frequencies to dry

    PubMed Central

    Dickerson, Andrew K.; Mills, Zachary G.; Hu, David L.

    2012-01-01

    In cold wet weather, mammals face hypothermia if they cannot dry themselves. By rapidly oscillating their bodies, through a process similar to shivering, furry mammals can dry themselves within seconds. We use high-speed videography and fur particle tracking to characterize the shakes of 33 animals (16 animals species and five dog breeds), ranging over four orders of magnitude in mass from mice to bears. We here report the power law relationship between shaking frequency f and body mass M to be f ∼ M−0.22, which is close to our prediction of f ∼ M−0.19 based upon the balance of centrifugal and capillary forces. We also observe a novel role for loose mammalian dermal tissue: by whipping around the body, it increases the speed of drops leaving the animal and the ensuing dryness relative to tight dermal tissue. PMID:22904256

  18. Enamel structure in some therapsids and mesozoic mammals.

    PubMed

    Osborn, J W; Hillman, J

    1979-11-01

    The distribution of enamel tubules, the shapes and arrangements of prisms, and the orientation of crystals in ground sections from several therapsids and mesozoic mammals have been investigated by conventional and polarizing microscopy. Along each of three separate phylogenetic lines which evolved occluding teeth, there was a progressive increase in the numbers of enamel tubules. In the investigation, the arcade-shaped prisms typical of recent mammals were first seen in material from the Cretaceous period. All the enamels investigated from the Triassic contained columns of crystals, which were deduced as hexagonal. The inner ends of the crystals within each column deviated towards the center of the column. It is concluded that the existence of an interprismatic region provides the most important distinction between prismatic enamels and the hexagonal columns of crystals in the Triassic material. PMID:116744

  19. Enamel structure in some therapsids and mesozoic mammals.

    PubMed

    Osborn, J W; Hillman, J

    1979-11-01

    The distribution of enamel tubules, the shapes and arrangements of prisms, and the orientation of crystals in ground sections from several therapsids and mesozoic mammals have been investigated by conventional and polarizing microscopy. Along each of three separate phylogenetic lines which evolved occluding teeth, there was a progressive increase in the numbers of enamel tubules. In the investigation, the arcade-shaped prisms typical of recent mammals were first seen in material from the Cretaceous period. All the enamels investigated from the Triassic contained columns of crystals, which were deduced as hexagonal. The inner ends of the crystals within each column deviated towards the center of the column. It is concluded that the existence of an interprismatic region provides the most important distinction between prismatic enamels and the hexagonal columns of crystals in the Triassic material.

  20. The evolution of acoustic size exaggeration in terrestrial mammals

    PubMed Central

    Charlton, Benjamin D.; Reby, David

    2016-01-01

    Recent studies have revealed that some mammals possess adaptations that enable them to produce vocal signals with much lower fundamental frequency (F0) and formant frequency spacing (ΔF) than expected for their size. Although these adaptations are assumed to reflect selection pressures for males to lower frequency components and exaggerate body size in reproductive contexts, this hypothesis has not been tested across a broad range of species. Here we show that male terrestrial mammals produce vocal signals with lower ΔF (but not F0) than expected for their size in mating systems with greater sexual size dimorphism. We also reveal that males produce calls with higher than expected F0 and ΔF in species with increased sperm competition. This investigation confirms that sexual selection favours the use of ΔF as an acoustic size exaggerator and supports the notion of an evolutionary trade-off between pre-copulatory signalling displays and sperm production. PMID:27598835

  1. Wet mammals shake at tuned frequencies to dry.

    PubMed

    Dickerson, Andrew K; Mills, Zachary G; Hu, David L

    2012-12-01

    In cold wet weather, mammals face hypothermia if they cannot dry themselves. By rapidly oscillating their bodies, through a process similar to shivering, furry mammals can dry themselves within seconds. We use high-speed videography and fur particle tracking to characterize the shakes of 33 animals (16 animals species and five dog breeds), ranging over four orders of magnitude in mass from mice to bears. We here report the power law relationship between shaking frequency f and body mass M to be f ∼ M(-0.22), which is close to our prediction of f ∼ M(-0.19) based upon the balance of centrifugal and capillary forces. We also observe a novel role for loose mammalian dermal tissue: by whipping around the body, it increases the speed of drops leaving the animal and the ensuing dryness relative to tight dermal tissue.

  2. Chlorinated hydrocarbon contaminants in arctic marine mammals.

    PubMed

    Norstrom, R J; Muir, D C

    1994-09-16

    By 1976, the presence of chlorinated hydrocarbon contaminants (CHCs) had been demonstrated in fur seal (Callorhinus ursinus), ringed seal (Phoca hispida), hooded seal (Cystophora cristata), bearded seal (Erignathus barbatus), walrus (Obdobenus rosmarus divergens), beluga (Delphinapterus leucas), porpoise (Phocoena phocoena) and polar bear (Ursus maritimus) in various parts of the Arctic. In spite of this early interest, very little subsequent research on contaminants in Arctic marine mammals was undertaken until the mid-1980s. Since that time, there has been an explosion of interest, resulting in a much expanded data base on contaminants in Arctic marine mammals. Except in the Russian Arctic, data have now been obtained on the temporospatial distribution of PCBs and other contaminants in ringed seal, beluga and polar bear. Contaminants in narwhal (Monodon monoceros) have also now been measured. On a fat weight basis, the sum of DDT-related compounds (S-DDT) and PCB levels are lowest in walrus (< 0.1 microgram/g), followed by ringed seal, (0.1-1 microgram/g range). Levels are an order of magnitude higher in beluga and narwhal (1-10 micrograms/g range). It appears that metabolism and excretion of S-DDT and PCBs may be less efficient in cetaceans, leading to greater biomagnification. Polar bears have similar levels of PCBs as cetaceans (1-10 micrograms/g), but with a much simpler congener pattern. DDE levels are lowest in polar bear, indicating rapid metabolism. Effects of age and sex on residue levels are found for all species where this was measured. Among cetaceans and ringed seal, sexually mature females have lower levels than males due to lactation. Although PCB levels in adult male polar bears are about twice as high as females, there is only a trivial age effect in either sex apart from an initial decrease from birth to sexual maturity (age 0-5). Comparison of levels of S-DDT and PCBs in Arctic beluga and ringed seal with those in beluga in the Gulf of St

  3. Corridors and olfactory predator cues affect small mammal behavior.

    SciTech Connect

    Brinkerhoff, Robert Jory; Haddad, Nick M.; Orrock, John L.

    2005-03-30

    Abstract The behavior of prey individuals is influenced by a variety of factors including, but not limited to, habitat configuration, risk of predation, and availability of resources, and these habitat-dependent factors may have interactive effects. We studied the responses of mice to an increase in perceived predation risk in a patchy environment to understand how habitat corridors might affect interactions among species in a fragmented landscape. We used a replicated experiment to investigate corridor-mediated prey responses to predator cues in a network of open habitat patches surrounded by a matrix of planted pine forest. Some of the patches were connected by corridors. We used mark–recapture techniques and foraging trays to monitor the movement, behavior, and abundance of small mammals. Predation threat was manipulated in one-half of the replicates by applying an olfactory predator cue. Corridors synchronized small mammal foraging activity among connected patches. Foraging also was inhibited in the presence of an olfactory predator cue but apparently increased in adjacent connected patches. Small mammal abundance did not change as a result of the predator manipulation and was not influenced by the presence of corridors. This study is among the 1st to indicate combined effects of landscape configuration and predation risk on prey behavior. These changes in prey behavior may, in turn, have cascading effects on community dynamics where corridors and differential predation risk influence movement and patch use.

  4. Absorption and ocular deposition of dietary lutein in marine mammals.

    PubMed

    Koutsos, Elizabeth A; Schmitt, Todd; Colitz, Carmen M H; Mazzaro, Lisa

    2013-01-01

    Cataracts and ocular disease are common lesions of marine mammals in zoological collections. Lutein, an oxygenated carotenoid, may have therapeutic or prophylactic effects on ocular disorder. Therefore, this study examined the ability of marine mammals to absorb dietary lutein. Two preliminary trials examined lutein in two forms (beadlet or ester) in a small sample size of marine mammals representing pinnipeds and cetaceans. Lutein was fed daily in tablets providing 0.89-3.6 mg lutein/kg body weight(0.75) per day for 15 days to 2 years. A third study was conducted using lutein beadlet fed at 3.6 mg lutein/kg body weight(0.75) per day for 15-21 days. Blood was analyzed for lutein pre- and postsupplementation. In the preliminary trials, lutein beadlet was observed to result in greater blood lutein levels than lutein esters, and cetaceans had more noticeable responses than pinnipeds. In Study 3, serum lutein and zeaxanthin increased postsupplementation in beluga whales (P < 0.05), and serum lutein tended to increase postsupplementation in dolphins (P < 0.10), but little change was seen in serum lutein in pinnipeds or manatee. Opportunistic retinal samples demonstrated some detectable lutein in the retina of a dolphin and several harp seals. The lutein levels in dolphins after supplementation are similar to those reported in free-ranging animals. Ocular lutein in harp seals demonstrates that ocular deposition occurs despite low circulating lutein levels. PMID:22753123

  5. Stress physiology in marine mammals: how well do they fit the terrestrial model?

    PubMed

    Atkinson, Shannon; Crocker, Daniel; Houser, Dorian; Mashburn, Kendall

    2015-07-01

    Stressors are commonly accepted as the causal factors, either internal or external, that evoke physiological responses to mediate the impact of the stressor. The majority of research on the physiological stress response, and costs incurred to an animal, has focused on terrestrial species. This review presents current knowledge on the physiology of the stress response in a lesser studied group of mammals, the marine mammals. Marine mammals are an artificial or pseudo grouping from a taxonomical perspective, as this group represents several distinct and diverse orders of mammals. However, they all are fully or semi-aquatic animals and have experienced selective pressures that have shaped their physiology in a manner that differs from terrestrial relatives. What these differences are and how they relate to the stress response is an efflorescent topic of study. The identification of the many facets of the stress response is critical to marine mammal management and conservation efforts. Anthropogenic stressors in marine ecosystems, including ocean noise, pollution, and fisheries interactions, are increasing and the dramatic responses of some marine mammals to these stressors have elevated concerns over the impact of human-related activities on a diverse group of animals that are difficult to monitor. This review covers the physiology of the stress response in marine mammals and places it in context of what is known from research on terrestrial mammals, particularly with respect to mediator activity that diverges from generalized terrestrial models. Challenges in conducting research on stress physiology in marine mammals are discussed and ways to overcome these challenges in the future are suggested.

  6. Stress physiology in marine mammals: how well do they fit the terrestrial model?

    PubMed

    Atkinson, Shannon; Crocker, Daniel; Houser, Dorian; Mashburn, Kendall

    2015-07-01

    Stressors are commonly accepted as the causal factors, either internal or external, that evoke physiological responses to mediate the impact of the stressor. The majority of research on the physiological stress response, and costs incurred to an animal, has focused on terrestrial species. This review presents current knowledge on the physiology of the stress response in a lesser studied group of mammals, the marine mammals. Marine mammals are an artificial or pseudo grouping from a taxonomical perspective, as this group represents several distinct and diverse orders of mammals. However, they all are fully or semi-aquatic animals and have experienced selective pressures that have shaped their physiology in a manner that differs from terrestrial relatives. What these differences are and how they relate to the stress response is an efflorescent topic of study. The identification of the many facets of the stress response is critical to marine mammal management and conservation efforts. Anthropogenic stressors in marine ecosystems, including ocean noise, pollution, and fisheries interactions, are increasing and the dramatic responses of some marine mammals to these stressors have elevated concerns over the impact of human-related activities on a diverse group of animals that are difficult to monitor. This review covers the physiology of the stress response in marine mammals and places it in context of what is known from research on terrestrial mammals, particularly with respect to mediator activity that diverges from generalized terrestrial models. Challenges in conducting research on stress physiology in marine mammals are discussed and ways to overcome these challenges in the future are suggested. PMID:25913694

  7. Apparatus for enhancing tissue repair in mammals

    NASA Technical Reports Server (NTRS)

    Goodwin, Thomas J. (Inventor); Parker, Clayton R. (Inventor)

    2007-01-01

    An apparatus is disclosed for enhancing tissue repair in mammals, with the apparatus comprising: a sleeve for encircling a portion of a mammalian body part, said sleeve comprising an electrically conductive coil capable of generating an electromagnetic field when an electrical current is applied thereto, means for supporting the sleeve on the mammalian body part; and means for supplying the electrically conductive coil with a square wave time varying electrical current sufficient to create a time varying electromagnetic force of from approximately 0.05 gauss to 0.05 gauss within the interior of the coil in order that when the sleeve is placed on a mammalian body part and the time varying electromagnetic force of from approximately 0.05 gauss to 0.05 gauss is generated on the mammalian body part for an extended period of time, tissue regeneration within the mammalian body part is increased to a rate in excess of the normal tissue regeneration rate that would occur without application of the time varying electromagnetic force.

  8. Isotope analyses of fossil small mammals in karstic sites

    NASA Astrophysics Data System (ADS)

    Garcia Alix, Antonio; Delgado Huertas, Antonio

    2016-04-01

    Fossil skeletal accumulations in kartstic complexes, such as caves, are quite common, especially during the Pliocene and Quaternary. These fossil assemblages are sometimes difficult to study, as specimens from different ages can be found together (time averaging). The traditional approach to study this kind of paleontological sites was taphonomic (understanding the origin and other factors affecting the bone accumulation) and/or taxonomic (systematic description of the remains). However, other kinds of analyses, such as biogeochemical techniques to reconstruct past diets and environments, are being more frequently used. Small-mammals have a wide geographical distribution, and their remains (bones and teeth) are extensively represented in the fossil record; therefore, isotopic analyses in fossil small-mammals are a powerful tool to reconstruct paleoenvironments. Field samples for small-mammal studies yield large amounts of sediment-residues that need to be reduced in the laboratory (usually by means of diluted hydrochloric or acetic acid). Therefore, samples of fossil small-mammal for isotopic analyses usually receive two different acid treatments: one to reduce the carbonate residue of the sediment, and afterwards another one to remove digenetic carbonates from the ground sample. Those treatments, along with the small size of the remains, may increase the probability of chemical fractionation during those pre-treatment stages. Those acid treatments are even more aggressive in kasrtic fossil localities, as limestone has to be dissolved to extract the small mammal remains. In this abstract, we present the results of two different treatments carried out in limestone from the Pliocene karstic locality of Moreda (Guadix Basin, Spain) and a control sample. One batch of samples were treated with a solution of 1M acetic acid-acetate calcium buffer (ph 4,5), and the rest with diluted acetic acid (at 15% concentration, Ph 2,2), which is the most used to reduce the sediments

  9. 75 FR 25729 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-07

    ...NMFS received an application from Shell Offshore Inc. (Shell) for an Incidental Harassment Authorization (IHA) to take marine mammals, by harassment, incidental to offshore exploration drilling on Outer Continental Shelf (OCS) leases in the Chukchi Sea, Alaska. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an IHA to Shell to take, by......

  10. 76 FR 35995 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Operation and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-21

    ... Federal Register (76 FR 34157; FR Doc. 2011-14614). The period of effectiveness in that notice is listed... preamble, FR Doc. 2011-14614, published June 13, 2011, at 76 FR 34157, is corrected as follows: 0 1. On... Mammals; Taking Marine Mammals Incidental to Operation and Maintenance of the Neptune Liquefied...

  11. Hazards of disease transfer from marine mammals to land mammals: review and recent findings.

    PubMed

    Smith, A W; Vedros, N A; Akers, T G; Gilmartin, W G

    1978-11-01

    In a 5-year study (1972-1977) of microbial agents isolated from both clinically normal and diseased marine mammals, it was shown that certain disease agents are widespread in a diversity of ocean populations and that some are also transmissible to a number of terrestrial mammal species. Leptospira interrogans serovar pomona has been isolated repeatedly from 2 species of pinnipeds (Zalophus californianus califonianus and Callorhinus ursinus). Some of the more important bacterial pathogens for land mammals that were isolated from wild marine mammals are Pseudomonas mallei, Clostridium chauvoei, C novyi, Neisseria mucosa var heidelbergensis, Klebsiella pneumoniae, Salmonella spp, and Pasteurella multocida. Numerous serotypes of viruses classified as caliciviruses were isolated from a variety of marine mammals. Some of these are known to infect several land mammal species including swine horses, and primates. For this reason., precautions should be taken to ensure that disease agents shed by captive marine mammals are not transmitted to susceptible terrestrial mammals, including animal handlers and other human beings. PMID:738931

  12. 77 FR 49921 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-17

    ...NMFS received an application from ION Geophysical (ION) for an Incidental Harassment Authorization (IHA) to take marine mammals, by harassment only, incidental to a proposed marine seismic survey in the Beaufort and Chukchi Seas, Alaska, between October and December 2012. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an IHA to ION to......

  13. 78 FR 12541 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-22

    ...NMFS received an application from ConocoPhillips Company (COP) for an Incidental Harassment Authorization (IHA) to take marine mammals, by harassment, incidental to offshore exploration drilling on Outer Continental Shelf (OCS) leases in the Chukchi Sea, Alaska. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an IHA to COP to take, by......

  14. 75 FR 80773 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-23

    ... Incidental to Specified Activities; Taking Marine Mammals Incidental to Space Vehicle and Missile Launch... to launching space launch vehicles, long-range ballistic target missiles, and other smaller missile... small numbers of marine mammals incidental to launching space launch vehicles, long-range...

  15. 77 FR 27321 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-09

    ... of an incidental harassment authorization. SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA) regulations, notification is hereby given that NMFS has issued an Incidental Harassment Authorization (IHA) to Shell Gulf of Mexico Inc. (Shell) to take marine mammals, by harassment, incidental...

  16. 78 FR 37209 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XC564 Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Marine Seismic Survey in the Beaufort Sea,...

  17. Effects of corridors on home range sizes and interpatch movements of three small mammal species.

    SciTech Connect

    Mabry, Karen, E.; Barrett, Gary, W.

    2002-04-30

    Mabry, K.E., and G.W. Barrett. 2002. Effects of corridors on home range sizes and interpatch movements of three small mammal species. Landscape Ecol. 17:629-636. Corridors are predicted to benefit populations in patchy habitats by promoting movement, which should increase population densities, gene flow, and recolonization of extinct patch populations. However, few investigators have considered use of the total landscape, particularly the possibility of interpatch movement through matrix habitat, by small mammals. This study compares home range sizes of 3 species of small mammals, the cotton mouse, old field mouse and cotton rat between patches with and without corridors. Corridor presence did not have a statistically significant influence on average home range size. Habitat specialization and sex influenced the probability of an individual moving between 2 patches without corridors. The results of this study suggest that small mammals may be more capable of interpatch movement without corridors than is frequently assumed.

  18. 'Candidatus Phytoplasma tamaricis', a novel taxon discovered in witches'-broom-diseased salt cedar (Tamarix chinensis Lour.).

    PubMed

    Zhao, Yan; Sun, Qingrong; Wei, Wei; Davis, Robert E; Wu, Wei; Liu, Qingzhong

    2009-10-01

    Salt cedar trees with pronounced witches'-broom symptoms were observed in their natural habitat in China. 16S rRNA gene sequences unique to phytoplasmas were detected in every DNA sample extracted from stem and leaf tissues of the symptomatic trees, revealing a direct association between phytoplasma infection and the salt cedar witches'-broom (SCWB) disease. Phylogenetic analysis of the SCWB phytoplasma 16S rRNA gene sequence indicated that the SCWB phytoplasma belonged to a subclade consisting of several mutually distinct 'Candidatus Phytoplasma' taxa including 'Ca. Phytoplasma prunorum', 'Ca. Phytoplasma mali', 'Ca. Phytoplasma pyri' and 'Ca. Phytoplasma spartii'. Pairwise sequence similarity scores calculated from an alignment of near full-length 16S rRNA genes revealed that SCWB phytoplasma shared 96.6 % or less sequence similarity with each previously described or proposed 'Ca. Phytoplasma' taxon, justifying the recognition of SCWB phytoplasma as a novel taxon, 'Candidatus Phytoplasma tamaricis'. The distinct virtual RFLP pattern derived from the SCWB phytoplasma 16S rRNA gene sequence, together with its lower-than-threshold similarity coefficient values with RFLP patterns of any of the 29 previously established groups, supported the recognition of a new 16Sr group, designated 16SrXXX, salt cedar witches'-broom phytoplasma group.

  19. The evolutionary diversification of parrots supports a taxon pulse model with multiple trans-oceanic dispersal events and local radiations.

    PubMed

    Schweizer, Manuel; Seehausen, Ole; Güntert, Marcel; Hertwig, Stefan T

    2010-03-01

    Vicariance is thought to have played a major role in the evolution of modern parrots. However, as the relationships especially of the African taxa remained mostly unresolved, it has been difficult to draw firm conclusions about the roles of dispersal and vicariance. Our analyses using the broadest taxon sampling of old world parrots ever based on 3219bp of three nuclear genes revealed well-resolved and congruent phylogenetic hypotheses. Agapornis of Africa and Madagascar was found to be the sister group to Loriculus of Australasia and Indo-Malayasia and together they clustered with the Australasian Loriinae, Cyclopsittacini and Melopsittacus. Poicephalus and Psittacus from mainland Africa formed the sister group of the Neotropical Arini and Coracopsis from Madagascar and adjacent islands may be the closest relative of Psittrichas from New Guinea. These biogeographic relationships are best explained by independent colonization of the African continent via trans-oceanic dispersal from Australasia and Antarctica in the Paleogene following what may have been vicariance events in the late Cretaceous and/or early Paleogene. Our data support a taxon pulse model for the diversification of parrots whereby trans-oceanic dispersal played a more important role than previously thought and was the prerequisite for range expansion into new continents.

  20. 'Candidatus Phytoplasma tamaricis', a novel taxon discovered in witches'-broom-diseased salt cedar (Tamarix chinensis Lour.).

    PubMed

    Zhao, Yan; Sun, Qingrong; Wei, Wei; Davis, Robert E; Wu, Wei; Liu, Qingzhong

    2009-10-01

    Salt cedar trees with pronounced witches'-broom symptoms were observed in their natural habitat in China. 16S rRNA gene sequences unique to phytoplasmas were detected in every DNA sample extracted from stem and leaf tissues of the symptomatic trees, revealing a direct association between phytoplasma infection and the salt cedar witches'-broom (SCWB) disease. Phylogenetic analysis of the SCWB phytoplasma 16S rRNA gene sequence indicated that the SCWB phytoplasma belonged to a subclade consisting of several mutually distinct 'Candidatus Phytoplasma' taxa including 'Ca. Phytoplasma prunorum', 'Ca. Phytoplasma mali', 'Ca. Phytoplasma pyri' and 'Ca. Phytoplasma spartii'. Pairwise sequence similarity scores calculated from an alignment of near full-length 16S rRNA genes revealed that SCWB phytoplasma shared 96.6 % or less sequence similarity with each previously described or proposed 'Ca. Phytoplasma' taxon, justifying the recognition of SCWB phytoplasma as a novel taxon, 'Candidatus Phytoplasma tamaricis'. The distinct virtual RFLP pattern derived from the SCWB phytoplasma 16S rRNA gene sequence, together with its lower-than-threshold similarity coefficient values with RFLP patterns of any of the 29 previously established groups, supported the recognition of a new 16Sr group, designated 16SrXXX, salt cedar witches'-broom phytoplasma group. PMID:19622657

  1. Cool sperm: why some placental mammals have a scrotum.

    PubMed

    Lovegrove, B G

    2014-05-01

    Throughout the Cenozoic, the fitness benefits of the scrotum in placental mammals presumably outweighed the fitness costs through damage, yet a definitive hypothesis for its evolution remains elusive. Here, I present an hypothesis (Endothermic Pulses Hypothesis) which argues that the evolution of the scrotum was driven by Cenozoic pulses in endothermy, that is, increases in normothermic body temperature, which occurred in Boreotheria (rodents, primates, lagomorphs, carnivores, bats, lipotyphylans and ungulates) in response to factors such as cursoriality and climate adaptation. The model argues that stabilizing selection maintained an optimum temperature for spermatogenesis and sperm storage throughout the Cenozoic at the lower plesiomorphic levels of body temperature that prevailed in ancestral mammals for at least 163 million years. Evolutionary stasis may have been driven by reduced rates of germ-cell mutations at lower body temperatures. Following the extinction of the dinosaurs at the Cretaceous-Palaeogene boundary 65.5 mya, immediate pulses in endothermy occurred associated with the dramatic radiation of the modern placental mammal orders. The fitness advantages of an optimum temperature of spermatogenesis outweighed the potential costs of testes externalization and paved the way for the evolution of the scrotum. The scrotum evolved within several hundred thousand years of the K-Pg extinction, probably associated initially with the evolution of cursoriality, and arguably facilitated mid- and late Cenozoic metabolic adaptations to factors such as climate, flight in bats and sociality in primates.

  2. Polyandry Has No Detectable Mortality Cost in Female Mammals

    PubMed Central

    Lemaître, Jean-François; Gaillard, Jean-Michel

    2013-01-01

    In several taxonomic groups, females mate with several males during a single reproductive cycle. Although there is evidence that polyandry provides some benefits to females, it often involves mortality costs. However, empirical evidences of mortality costs of polyandry have so far been reported only in invertebrates. Whether polyandry has mortality costs in vertebrates is currently unknown. In the present study, we aimed to fill the gap by investigating the relationships between the level of polyandry (measured either by male relative testes mass or the percentage of multiple paternities) and female patterns of mortality across mammals. While we found that the two metrics of female mortality co-varied with pace of life, we did not find any evidence that polyandry leads to either decreased median lifespan or increased aging rate in mammals. We discuss such an absence of detectable mortality costs of polyandry in female mammals in light of recent advances in the study of mammalian reproductive biology and life-history tactics. PMID:23825000

  3. Cold and hunger induce diurnality in a nocturnal mammal.

    PubMed

    van der Vinne, Vincent; Riede, Sjaak J; Gorter, Jenke A; Eijer, Willem G; Sellix, Michael T; Menaker, Michael; Daan, Serge; Pilorz, Violetta; Hut, Roelof A

    2014-10-21

    The mammalian circadian system synchronizes daily timing of activity and rest with the environmental light-dark cycle. Although the underlying molecular oscillatory mechanism is well studied, factors that influence phenotypic plasticity in daily activity patterns (temporal niche switching, chronotype) are presently unknown. Molecular evidence suggests that metabolism may influence the circadian molecular clock, but evidence at the level of the organism is lacking. Here we show that a metabolic challenge by cold and hunger induces diurnality in otherwise nocturnal mice. Lowering ambient temperature changes the phase of circadian light-dark entrainment in mice by increasing daytime and decreasing nighttime activity. This effect is further enhanced by simulated food shortage, which identifies metabolic balance as the underlying common factor influencing circadian organization. Clock gene expression analysis shows that the underlying neuronal mechanism is downstream from or parallel to the main circadian pacemaker (the hypothalamic suprachiasmatic nucleus) and that the behavioral phenotype is accompanied by phase adjustment of peripheral tissues. These findings indicate that nocturnal mammals can display considerable plasticity in circadian organization and may adopt a diurnal phenotype when energetically challenged. Our previously defined circadian thermoenergetics hypothesis proposes that such circadian plasticity, which naturally occurs in nocturnal mammals, reflects adaptive maintenance of energy balance. Quantification of energy expenditure shows that diurnality under natural conditions reduces thermoregulatory costs in small burrowing mammals like mice. Metabolic feedback on circadian organization thus provides functional benefits by reducing energy expenditure. Our findings may help to clarify relationships between sleep-wake patterns and metabolic phenotypes in humans. PMID:25288753

  4. Cold and hunger induce diurnality in a nocturnal mammal.

    PubMed

    van der Vinne, Vincent; Riede, Sjaak J; Gorter, Jenke A; Eijer, Willem G; Sellix, Michael T; Menaker, Michael; Daan, Serge; Pilorz, Violetta; Hut, Roelof A

    2014-10-21

    The mammalian circadian system synchronizes daily timing of activity and rest with the environmental light-dark cycle. Although the underlying molecular oscillatory mechanism is well studied, factors that influence phenotypic plasticity in daily activity patterns (temporal niche switching, chronotype) are presently unknown. Molecular evidence suggests that metabolism may influence the circadian molecular clock, but evidence at the level of the organism is lacking. Here we show that a metabolic challenge by cold and hunger induces diurnality in otherwise nocturnal mice. Lowering ambient temperature changes the phase of circadian light-dark entrainment in mice by increasing daytime and decreasing nighttime activity. This effect is further enhanced by simulated food shortage, which identifies metabolic balance as the underlying common factor influencing circadian organization. Clock gene expression analysis shows that the underlying neuronal mechanism is downstream from or parallel to the main circadian pacemaker (the hypothalamic suprachiasmatic nucleus) and that the behavioral phenotype is accompanied by phase adjustment of peripheral tissues. These findings indicate that nocturnal mammals can display considerable plasticity in circadian organization and may adopt a diurnal phenotype when energetically challenged. Our previously defined circadian thermoenergetics hypothesis proposes that such circadian plasticity, which naturally occurs in nocturnal mammals, reflects adaptive maintenance of energy balance. Quantification of energy expenditure shows that diurnality under natural conditions reduces thermoregulatory costs in small burrowing mammals like mice. Metabolic feedback on circadian organization thus provides functional benefits by reducing energy expenditure. Our findings may help to clarify relationships between sleep-wake patterns and metabolic phenotypes in humans.

  5. Evidence for a Mid-Jurassic Adaptive Radiation in Mammals.

    PubMed

    Close, Roger A; Friedman, Matt; Lloyd, Graeme T; Benson, Roger B J

    2015-08-17

    A series of spectacular discoveries have transformed our understanding of Mesozoic mammals in recent years. These finds reveal hitherto-unsuspected ecomorphological diversity that suggests that mammals experienced a major adaptive radiation during the Middle to Late Jurassic. Patterns of mammalian macroevolution must be reinterpreted in light of these new discoveries, but only taxonomic diversity and limited aspects of morphological disparity have been quantified. We assess rates of morphological evolution and temporal patterns of disparity using large datasets of discrete characters. Rates of morphological evolution were significantly elevated prior to the Late Jurassic, with a pronounced peak occurring during the Early to Middle Jurassic. This intense burst of phenotypic innovation coincided with a stepwise increase in apparent long-term standing diversity and the attainment of maximum disparity, supporting a "short-fuse" model of early mammalian diversification. Rates then declined sharply, and remained significantly low until the end of the Mesozoic, even among therians. This supports the "long-fuse" model of diversification in Mesozoic therians. Our findings demonstrate that sustained morphological innovation in Triassic stem-group mammals culminated in a global adaptive radiation of crown-group members during the Early to Middle Jurassic. PMID:26190074

  6. Ecological predictors of extinction risks of endemic mammals of China

    PubMed Central

    CHEN, You-Hua

    2014-01-01

    In this brief report, we analyzed ecological correlates of risk of extinction for mammals endemic to China using phylogenetic eigenvector methods to control for the effect of phylogenetic inertia. Extinction risks were based on the International Union for Conservation of Nature (IUCN) Red List and ecological explanatory attributes that include range size and climatic variables. When the effect of phylogenetic inertia were controlled, climate became the best predictor for quantifying and evaluating extinction risks of endemic mammals in China, accounting for 13% of the total variation. Range size seems to play a trivial role, explaining ~1% of total variation; however, when non-phylogenetic variation partitioning analysis was done, the role of range size then explained 7.4% of total variation. Consequently, phylogenetic inertia plays a substantial role in increasing the explanatory power of range size on the extinction risks of mammals endemic to China. Limitations of the present study are discussed, with a focus on under-represented sampling of endemic mammalian species. PMID:25017756

  7. Evidence for a Mid-Jurassic Adaptive Radiation in Mammals.

    PubMed

    Close, Roger A; Friedman, Matt; Lloyd, Graeme T; Benson, Roger B J

    2015-08-17

    A series of spectacular discoveries have transformed our understanding of Mesozoic mammals in recent years. These finds reveal hitherto-unsuspected ecomorphological diversity that suggests that mammals experienced a major adaptive radiation during the Middle to Late Jurassic. Patterns of mammalian macroevolution must be reinterpreted in light of these new discoveries, but only taxonomic diversity and limited aspects of morphological disparity have been quantified. We assess rates of morphological evolution and temporal patterns of disparity using large datasets of discrete characters. Rates of morphological evolution were significantly elevated prior to the Late Jurassic, with a pronounced peak occurring during the Early to Middle Jurassic. This intense burst of phenotypic innovation coincided with a stepwise increase in apparent long-term standing diversity and the attainment of maximum disparity, supporting a "short-fuse" model of early mammalian diversification. Rates then declined sharply, and remained significantly low until the end of the Mesozoic, even among therians. This supports the "long-fuse" model of diversification in Mesozoic therians. Our findings demonstrate that sustained morphological innovation in Triassic stem-group mammals culminated in a global adaptive radiation of crown-group members during the Early to Middle Jurassic.

  8. Ecological predictors of extinction risks of endemic mammals of China.

    PubMed

    Chen, You-Hua

    2014-07-01

    In this brief report, we analyzed ecological correlates of risk of extinction for mammals endemic to China using phylogenetic eigenvector methods to control for the effect of phylogenetic inertia. Extinction risks were based on the International Union for Conservation of Nature (IUCN) Red List and ecological explanatory attributes that include range size and climatic variables. When the effect of phylogenetic inertia were controlled, climate became the best predictor for quantifying and evaluating extinction risks of endemic mammals in China, accounting for 13% of the total variation. Range size seems to play a trivial role, explaining ~1% of total variation; however, when non-phylogenetic variation partitioning analysis was done, the role of range size then explained 7.4% of total variation. Consequently, phylogenetic inertia plays a substantial role in increasing the explanatory power of range size on the extinction risks of mammals endemic to China. Limitations of the present study are discussed, with a focus on under-represented sampling of endemic mammalian species.

  9. Responses of large mammals to climate change

    PubMed Central

    Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

    2014-01-01

    Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change.

  10. Responses of large mammals to climate change

    PubMed Central

    Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

    2014-01-01

    Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change. PMID:27583293

  11. Responses of large mammals to climate change.

    PubMed

    Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

    2014-01-01

    Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change. PMID:27583293

  12. Responses of large mammals to climate change.

    PubMed

    Hetem, Robyn S; Fuller, Andrea; Maloney, Shane K; Mitchell, Duncan

    2014-01-01

    Most large terrestrial mammals, including the charismatic species so important for ecotourism, do not have the luxury of rapid micro-evolution or sufficient range shifts as strategies for adjusting to climate change. The rate of climate change is too fast for genetic adaptation to occur in mammals with longevities of decades, typical of large mammals, and landscape fragmentation and population by humans too widespread to allow spontaneous range shifts of large mammals, leaving only the expression of latent phenotypic plasticity to counter effects of climate change. The expression of phenotypic plasticity includes anatomical variation within the same species, changes in phenology, and employment of intrinsic physiological and behavioral capacity that can buffer an animal against the effects of climate change. Whether that buffer will be realized is unknown, because little is known about the efficacy of the expression of plasticity, particularly for large mammals. Future research in climate change biology requires measurement of physiological characteristics of many identified free-living individual animals for long periods, probably decades, to allow us to detect whether expression of phenotypic plasticity will be sufficient to cope with climate change.

  13. Phosphatidylcholine composition of pulmonary surfactant from terrestrial and marine diving mammals.

    PubMed

    Gutierrez, Danielle B; Fahlman, Andreas; Gardner, Manuela; Kleinhenz, Danielle; Piscitelli, Marina; Raverty, Stephen; Haulena, Martin; Zimba, Paul V

    2015-06-01

    Marine mammals are repeatedly exposed to elevated extra-thoracic pressure and alveolar collapse during diving and readily experience alveolar expansion upon inhalation - a unique capability as compared to terrestrial mammals. How marine mammal lungs overcome the challenges of frequent alveolar collapse and recruitment remains unknown. Recent studies indicate that pinniped lung surfactant has more anti-adhesive components compared to terrestrial mammals, which would aid in alveolar opening. However, pulmonary surfactant composition has not yet been investigated in odontocetes, whose physiology and diving behavior differ from pinnipeds. The aim of this study was to investigate the phosphatidylcholine (PC) composition of lung surfactants from various marine mammals and compare these to a terrestrial mammal. We found an increase in anti-adhesive PC species in harp seal (Pagophilus groenlandicus) and California sea lion (Zalophus californianus) compared to dog (Canus lupus familiaris), as well as an increase in the fluidizing PCs 16:0/14:0 and 16:0/16:1 in pinnipeds compared to odontocetes. The harbor porpoise (a representative of the odontocetes) did not have higher levels of fluidizing PCs compared to dog. Our preliminary results support previous findings that pinnipeds may have adapted unique surfactant compositions that allow them to dive at high pressures for extended periods without adverse effects. Future studies will need to investigate the differences in other surfactant components to fully assess the surfactant composition in odontocetes.

  14. Phosphatidylcholine composition of pulmonary surfactant from terrestrial and marine diving mammals

    PubMed Central

    Gutierrez, Danielle B.; Fahlman, Andreas; Gardner, Manuela; Kleinhenz, Danielle; Piscitelli, Marina; Raverty, Stephen; Haulena, Martin; Zimba, Paul V.

    2015-01-01

    Marine mammals are repeatedly exposed to elevated extra-thoracic pressure and alveolar collapse during diving and readily experience alveolar expansion upon inhalation – a unique capability as compared to terrestrial mammals. How marine mammal lungs overcome the challenges of frequent alveolar collapse and recruitment remains unknown. Recent studies indicate that pinniped lung surfactant has more anti-adhesive components compared to terrestrial mammals, which would aid in alveolar opening. However, pulmonary surfactant composition has not yet been investigated in odontocetes, whose physiology and diving behavior differ from pinnipeds. The aim of this study was to investigate the phosphatidylcholine (PC) composition of lung surfactants from various marine mammals and compare these to a terrestrial mammal. We found an increase in anti-adhesive PC species in harp seal (Pagophilus groenlandicus) and California sea lion (Zalophus californianus) compared to dog (Canus lupus familiaris), as well as an increase in the fluidizing PCs 16:0/14:0 and 16:0/16:1 in pinnipeds compared to odontocetes. The harbor porpoise (a representative of the odontocetes) did not have higher levels of fluidizing PCs compared to dog. Our preliminary results support previous findings that pinnipeds may have adapted unique surfactant compositions that allow them to dive at high pressures for extended periods without adverse effects. Future studies will need to investigate the differences in other surfactant components to fully assess the surfactant composition in odontocetes. PMID:25812797

  15. Phosphatidylcholine composition of pulmonary surfactant from terrestrial and marine diving mammals.

    PubMed

    Gutierrez, Danielle B; Fahlman, Andreas; Gardner, Manuela; Kleinhenz, Danielle; Piscitelli, Marina; Raverty, Stephen; Haulena, Martin; Zimba, Paul V

    2015-06-01

    Marine mammals are repeatedly exposed to elevated extra-thoracic pressure and alveolar collapse during diving and readily experience alveolar expansion upon inhalation - a unique capability as compared to terrestrial mammals. How marine mammal lungs overcome the challenges of frequent alveolar collapse and recruitment remains unknown. Recent studies indicate that pinniped lung surfactant has more anti-adhesive components compared to terrestrial mammals, which would aid in alveolar opening. However, pulmonary surfactant composition has not yet been investigated in odontocetes, whose physiology and diving behavior differ from pinnipeds. The aim of this study was to investigate the phosphatidylcholine (PC) composition of lung surfactants from various marine mammals and compare these to a terrestrial mammal. We found an increase in anti-adhesive PC species in harp seal (Pagophilus groenlandicus) and California sea lion (Zalophus californianus) compared to dog (Canus lupus familiaris), as well as an increase in the fluidizing PCs 16:0/14:0 and 16:0/16:1 in pinnipeds compared to odontocetes. The harbor porpoise (a representative of the odontocetes) did not have higher levels of fluidizing PCs compared to dog. Our preliminary results support previous findings that pinnipeds may have adapted unique surfactant compositions that allow them to dive at high pressures for extended periods without adverse effects. Future studies will need to investigate the differences in other surfactant components to fully assess the surfactant composition in odontocetes. PMID:25812797

  16. Adaptive radiation of multituberculate mammals before the extinction of dinosaurs.

    PubMed

    Wilson, Gregory P; Evans, Alistair R; Corfe, Ian J; Smits, Peter D; Fortelius, Mikael; Jernvall, Jukka

    2012-03-14

    The Cretaceous-Paleogene mass extinction approximately 66 million years ago is conventionally thought to have been a turning point in mammalian evolution. Prior to that event and for the first two-thirds of their evolutionary history, mammals were mostly confined to roles as generalized, small-bodied, nocturnal insectivores, presumably under selection pressures from dinosaurs. Release from these pressures, by extinction of non-avian dinosaurs at the Cretaceous-Paleogene boundary, triggered ecological diversification of mammals. Although recent individual fossil discoveries have shown that some mammalian lineages diversified ecologically during the Mesozoic era, comprehensive ecological analyses of mammalian groups crossing the Cretaceous-Paleogene boundary are lacking. Such analyses are needed because diversification analyses of living taxa allow only indirect inferences of past ecosystems. Here we show that in arguably the most evolutionarily successful clade of Mesozoic mammals, the Multituberculata, an adaptive radiation began at least 20 million years before the extinction of non-avian dinosaurs and continued across the Cretaceous-Paleogene boundary. Disparity in dental complexity, which relates to the range of diets, rose sharply in step with generic richness and disparity in body size. Moreover, maximum dental complexity and body size demonstrate an adaptive shift towards increased herbivory. This dietary expansion tracked the ecological rise of angiosperms and suggests that the resources that were available to multituberculates were relatively unaffected by the Cretaceous-Paleogene mass extinction. Taken together, our results indicate that mammals were able to take advantage of new ecological opportunities in the Mesozoic and that at least some of these opportunities persisted through the Cretaceous-Paleogene mass extinction. Similar broad-scale ecomorphological inventories of other radiations may help to constrain the possible causes of mass extinctions.

  17. Current and Future Patterns of Global Marine Mammal Biodiversity

    PubMed Central

    Kaschner, Kristin; Tittensor, Derek P.; Ready, Jonathan; Gerrodette, Tim; Worm, Boris

    2011-01-01

    Quantifying the spatial distribution of taxa is an important prerequisite for the preservation of biodiversity, and can provide a baseline against which to measure the impacts of climate change. Here we analyse patterns of marine mammal species richness based on predictions of global distributional ranges for 115 species, including all extant pinnipeds and cetaceans. We used an environmental suitability model specifically designed to address the paucity of distributional data for many marine mammal species. We generated richness patterns by overlaying predicted distributions for all species; these were then validated against sightings data from dedicated long-term surveys in the Eastern Tropical Pacific, the Northeast Atlantic and the Southern Ocean. Model outputs correlated well with empirically observed patterns of biodiversity in all three survey regions. Marine mammal richness was predicted to be highest in temperate waters of both hemispheres with distinct hotspots around New Zealand, Japan, Baja California, the Galapagos Islands, the Southeast Pacific, and the Southern Ocean. We then applied our model to explore potential changes in biodiversity under future perturbations of environmental conditions. Forward projections of biodiversity using an intermediate Intergovernmental Panel for Climate Change (IPCC) temperature scenario predicted that projected ocean warming and changes in sea ice cover until 2050 may have moderate effects on the spatial patterns of marine mammal richness. Increases in cetacean richness were predicted above 40° latitude in both hemispheres, while decreases in both pinniped and cetacean richness were expected at lower latitudes. Our results show how species distribution models can be applied to explore broad patterns of marine biodiversity worldwide for taxa for which limited distributional data are available. PMID:21625431

  18. Adaptive radiation of multituberculate mammals before the extinction of dinosaurs.

    PubMed

    Wilson, Gregory P; Evans, Alistair R; Corfe, Ian J; Smits, Peter D; Fortelius, Mikael; Jernvall, Jukka

    2012-03-22

    The Cretaceous-Paleogene mass extinction approximately 66 million years ago is conventionally thought to have been a turning point in mammalian evolution. Prior to that event and for the first two-thirds of their evolutionary history, mammals were mostly confined to roles as generalized, small-bodied, nocturnal insectivores, presumably under selection pressures from dinosaurs. Release from these pressures, by extinction of non-avian dinosaurs at the Cretaceous-Paleogene boundary, triggered ecological diversification of mammals. Although recent individual fossil discoveries have shown that some mammalian lineages diversified ecologically during the Mesozoic era, comprehensive ecological analyses of mammalian groups crossing the Cretaceous-Paleogene boundary are lacking. Such analyses are needed because diversification analyses of living taxa allow only indirect inferences of past ecosystems. Here we show that in arguably the most evolutionarily successful clade of Mesozoic mammals, the Multituberculata, an adaptive radiation began at least 20 million years before the extinction of non-avian dinosaurs and continued across the Cretaceous-Paleogene boundary. Disparity in dental complexity, which relates to the range of diets, rose sharply in step with generic richness and disparity in body size. Moreover, maximum dental complexity and body size demonstrate an adaptive shift towards increased herbivory. This dietary expansion tracked the ecological rise of angiosperms and suggests that the resources that were available to multituberculates were relatively unaffected by the Cretaceous-Paleogene mass extinction. Taken together, our results indicate that mammals were able to take advantage of new ecological opportunities in the Mesozoic and that at least some of these opportunities persisted through the Cretaceous-Paleogene mass extinction. Similar broad-scale ecomorphological inventories of other radiations may help to constrain the possible causes of mass extinctions

  19. Influenza Virus Infection of Marine Mammals.

    PubMed

    Fereidouni, Sasan; Munoz, Olga; Von Dobschuetz, Sophie; De Nardi, Marco

    2016-03-01

    Interspecies transmission may play a key role in the evolution and ecology of influenza A viruses. The importance of marine mammals as hosts or carriers of potential zoonotic pathogens such as highly pathogenic H5 and H7 influenza viruses is not well understood. The fact that influenza viruses are some of the few zoonotic pathogens known to have caused infection in marine mammals, evidence for direct transmission of influenza A virus H7N7 subtype from seals to man, transmission of pandemic H1N1 influenza viruses to seals and also limited evidence for long-term persistence of influenza B viruses in seal populations without significant genetic change, makes monitoring of influenza viruses in marine mammal populations worth being performed. In addition, such monitoring studies could be a great tool to better understand the ecology of influenza viruses in nature. PMID:25231137

  20. Climate directly influences Eocene mammal faunal dynamics in North America

    PubMed Central

    Woodburne, Michael O.; Gunnell, Gregg F.; Stucky, Richard K.

    2009-01-01

    The modern effect of climate on plants and animals is well documented. Some have cautioned against assigning climate a direct role in Cenozoic land mammal faunal changes. We illustrate 3 episodes of significant mammalian reorganization in the Eocene of North America that are considered direct responses to dramatic climatic events. The first episode occurred during the Paleocene–Eocene Thermal Maximum (PETM), beginning the Eocene (55.8 Ma), and earliest Wasatchian North American Land Mammal Age (NALMA). The PETM documents a short (<170 k.y.) global temperature increase of ≈5 °C and a substantial increase in first appearances of mammals traced to climate-induced immigration. A 4-m.y. period of climatic and evolutionary stasis then ensued. The second climate episode, the late early Eocene Climatic Optimum (EECO, 53–50 Ma), is marked by a temperature increase to the highest prolonged Cenozoic ocean temperature and a similarly distinctive continental interior mean annual temperature (MAT) of 23 °C. This MAT increase [and of mean annual precipitation (MAP) to 150 cm/y) promoted a major increase in floral diversity and habitat complexity under temporally unique, moist, paratropical conditions. Subsequent climatic deterioration in a third interval, from 50 to 47 Ma, resulted in major faunal diversity loss at both continental and local scales. In this Bridgerian Crash, relative abundance shifted from very diverse, evenly represented, communities to those dominated by the condylarth Hyopsodus. Rather than being “optimum,” the EECO began the greatest episode of faunal turnover of the first 15 m.y. of the Cenozoic. PMID:19666605

  1. Climate directly influences Eocene mammal faunal dynamics in North America.

    PubMed

    Woodburne, Michael O; Gunnell, Gregg F; Stucky, Richard K

    2009-08-11

    The modern effect of climate on plants and animals is well documented. Some have cautioned against assigning climate a direct role in Cenozoic land mammal faunal changes. We illustrate 3 episodes of significant mammalian reorganization in the Eocene of North America that are considered direct responses to dramatic climatic events. The first episode occurred during the Paleocene-Eocene Thermal Maximum (PETM), beginning the Eocene (55.8 Ma), and earliest Wasatchian North American Land Mammal Age (NALMA). The PETM documents a short (<170 k.y.) global temperature increase of approximately 5 degrees C and a substantial increase in first appearances of mammals traced to climate-induced immigration. A 4-m.y. period of climatic and evolutionary stasis then ensued. The second climate episode, the late early Eocene Climatic Optimum (EECO, 53-50 Ma), is marked by a temperature increase to the highest prolonged Cenozoic ocean temperature and a similarly distinctive continental interior mean annual temperature (MAT) of 23 degrees C. This MAT increase [and of mean annual precipitation (MAP) to 150 cm/y) promoted a major increase in floral diversity and habitat complexity under temporally unique, moist, paratropical conditions. Subsequent climatic deterioration in a third interval, from 50 to 47 Ma, resulted in major faunal diversity loss at both continental and local scales. In this Bridgerian Crash, relative abundance shifted from very diverse, evenly represented, communities to those dominated by the condylarth Hyopsodus. Rather than being "optimum," the EECO began the greatest episode of faunal turnover of the first 15 m.y. of the Cenozoic. PMID:19666605

  2. New Specimens of the Rare Taeniodont Wortmania (Mammalia: Eutheria) from the San Juan Basin of New Mexico and Comments on the Phylogeny and Functional Morphology of “Archaic” Mammals

    PubMed Central

    Williamson, Thomas E.; Brusatte, Stephen L.

    2013-01-01

    Background Taeniodonta is a clade of Late Cretaceous – Paleogene mammals remarkable for their relatively extreme cranial, dental, and postcranial adaptations and notable for being among the first mammals to achieve relatively large size following the Cretaceous-Paleogene mass extinction. Previous workers have hypothesized that taeniodonts can be divided into two clades: Conoryctidae, a group of small-bodied taeniodonts with supposedly “generalized” postcranial skeletons, and Stylinodontidae, a group of large-bodied, robust animals with massive forelimbs and claws adapted for scratch-digging. However, many taeniodont taxa are poorly known and few are represented by postcranial material, leaving many details about their anatomy, biology, and evolution ambiguous. Methodology/Principal Findings In this paper, we describe three new specimens of the rare taxon Wortmaniaotariidens from the early Paleocene (Puercan) of New Mexico. Among these specimens is one that includes remarkably complete cranial and dental material, including associated upper and lower teeth, and another that consists of partial forelimbs. These specimens allow for an updated anatomical description of this unusual taxon, supply new data for phylogenetic analyses, and enable a more constrained discussion of taeniodont biology and functional morphology. Conclusions/Significance The new specimen of Wortmania that includes associated upper and lower teeth indicates that previous interpretations of the upper dentition of this taxon were not accurate and the taxon Robertschochiasullivani is a junior synonym of W. otariidens. New specimens that include partial forelimbs indicate that Wortmania is very similar to later, large-bodied taeniodonts, with marked and distinctive adaptations for scratch-digging. Comparisons with other taeniodont taxa that include postcranial material suggest that all taeniodonts may have had scratch-digging adaptations. A phylogenetic analysis shows that Schowalteria and

  3. Anthropogenic environments exert variable selection on cranial capacity in mammals

    PubMed Central

    Snell-Rood, Emilie C.; Wick, Naomi

    2013-01-01

    It is thought that behaviourally flexible species will be able to cope with novel and rapidly changing environments associated with human activity. However, it is unclear whether such environments are selecting for increases in behavioural plasticity, and whether some species show more pronounced evolutionary changes in plasticity. To test whether anthropogenic environments are selecting for increased behavioural plasticity within species, we measured variation in relative cranial capacity over time and space in 10 species of mammals. We predicted that urban populations would show greater cranial capacity than rural populations and that cranial capacity would increase over time in urban populations. Based on relevant theory, we also predicted that species capable of rapid population growth would show more pronounced evolutionary responses. We found that urban populations of two small mammal species had significantly greater cranial capacity than rural populations. In addition, species with higher fecundity showed more pronounced differentiation between urban and rural populations. Contrary to expectations, we found no increases in cranial capacity over time in urban populations—indeed, two species tended to have a decrease in cranial capacity over time in urban populations. Furthermore, rural populations of all insectivorous species measured showed significant increases in relative cranial capacity over time. Our results provide partial support for the hypothesis that urban environments select for increased behavioural plasticity, although this selection may be most pronounced early during the urban colonization process. Furthermore, these data also suggest that behavioural plasticity may be simultaneously favoured in rural environments, which are also changing because of human activity. PMID:23966638

  4. Anthropogenic environments exert variable selection on cranial capacity in mammals.

    PubMed

    Snell-Rood, Emilie C; Wick, Naomi

    2013-10-22

    It is thought that behaviourally flexible species will be able to cope with novel and rapidly changing environments associated with human activity. However, it is unclear whether such environments are selecting for increases in behavioural plasticity, and whether some species show more pronounced evolutionary changes in plasticity. To test whether anthropogenic environments are selecting for increased behavioural plasticity within species, we measured variation in relative cranial capacity over time and space in 10 species of mammals. We predicted that urban populations would show greater cranial capacity than rural populations and that cranial capacity would increase over time in urban populations. Based on relevant theory, we also predicted that species capable of rapid population growth would show more pronounced evolutionary responses. We found that urban populations of two small mammal species had significantly greater cranial capacity than rural populations. In addition, species with higher fecundity showed more pronounced differentiation between urban and rural populations. Contrary to expectations, we found no increases in cranial capacity over time in urban populations-indeed, two species tended to have a decrease in cranial capacity over time in urban populations. Furthermore, rural populations of all insectivorous species measured showed significant increases in relative cranial capacity over time. Our results provide partial support for the hypothesis that urban environments select for increased behavioural plasticity, although this selection may be most pronounced early during the urban colonization process. Furthermore, these data also suggest that behavioural plasticity may be simultaneously favoured in rural environments, which are also changing because of human activity.

  5. Spectral detection and monitoring of marine mammals

    NASA Astrophysics Data System (ADS)

    Schoonmaker, Jon; Wells, Tami; Gilbert, Gary; Podobna, Yuliya; Petrosyuk, Irina; Dirbas, Joseph

    2008-04-01

    This note presents an airborne spectral imaging system and methodology used to detect, track and monitor marine mammal populations. The system is a four band multispectral imaging system using spectral bands tailored for maritime imaging. This low cost, low volume, imaging sensor can be deployed on either a small unmanned air vehicle (UAV) or any other cost efficient aircraft. Results of recent multispectral data collects over marine mammals in St. Lawrence Seaway are presented. Species present included beluga whales as well as various species of larger baleen whales.

  6. The changing focus of marine mammal conservation.

    PubMed

    Hofman, R J

    1995-11-01

    Overexploitation has been the principal focus of marine mammal conservation. Less attention has been paid to bycatch in commercial fisheries; entanglement in lost and discarded fishing gear; food shortages owing to climate change and/or overharvesting of essential prey; point and non-point source pollution; and diseases. Also, relatively little attention has been paid to situations where marine mammals pose threats to the existence and human uses of other marine species. As overexploitation is addressed, focus must be shifted to these problems that are no less significant.

  7. Advances in exotic mammal clinical therapeutics.

    PubMed

    Hawkins, Michelle G

    2015-05-01

    It is important that veterinarians treating exotic companion mammals stay abreast of the latest developments relating to medications and drug delivery approaches for safety, efficacy and welfare issues. Sustained release formulations of commonly used drugs as well as newer routes for administration of therapeutic agents allow the veterinarian treating exotic companion mammals to reduce the stress associated with drug administration. Interactions can occur between vehicle and drugs when formulations are compounded, therefore research studies are warranted regarding potential problems associated with these formulations. PMID:25902274

  8. Seasonal variations of marine protist community structure based on taxon-specific traits using the eastern English Channel as a model coastal system.

    PubMed

    Genitsaris, Savvas; Monchy, Sébastien; Viscogliosi, Eric; Sime-Ngando, Télesphore; Ferreira, Stéphanie; Christaki, Urania

    2015-05-01

    Previous microscopy-based studies in the eastern English Channel have revealed it to be a productive meso-eutrophic coastal ecosystem, characterized by strong repeating patterns in microplankton succession. The present study examines the seasonal structure of the entire protistan community from March 2011 to July 2013, using tag pyrosequencing of the V2-V3 hypervariable region of the 18S rRNA gene. A total of 1242 OTUs and 28 high-level taxonomic groups, which included previously undetected taxa in the area, were identified. The detected OTUs were considered according to taxon-specific traits, which included their trophic role, abundance and specialization level. Taxa differentiation based on specialization level rather than abundance was more informative in describing community organization. While generalists were always abundant, numerous specialists that were either rare or absent in most samples, increased in abundance for short periods, appearing to be overall abundant. Statistical and network analyses showed that the protistan seasonal organization was influenced by environmental parameters. It also highlighted that in addition to grazers, fungi and parasites played potentially significant roles during phytoplankton blooms. Overall, while the protistan succession was mainly shaped by environmental variations, biotic interactions among co-occurring taxa were the main structural drivers of the temporal assemblages.

  9. Predicting small mammal and flea abundance using landform and soil properties in a plague endemic area in Lushoto District, Tanzania.

    PubMed

    Meliyo, Joel L; Kimaro, Didas N; Msanya, Balthazar M; Mulungu, Loth S; Hieronimo, Proches; Kihupi, Nganga I; Gulinck, Hubert; Deckers, Jozef A

    2014-07-01

    Small mammals particularly rodents, are considered the primary natural hosts of plague. Literature suggests that plague persistence in natural foci has a root cause in soils. The objective of this study was to investigate the relationship between on the one hand landforms and associated soil properties, and on the other hand small mammals and fleas in West Usambara Mountains in Tanzania, a plague endemic area. Standard field survey methods coupled with Geographical Information System (GIS) technique were used to examine landform and soils characteristics. Soil samples were analysed in the laboratory for physico-chemical properties. Small mammals were trapped on pre-established landform positions and identified to genus/species level. Fleas were removed from the trapped small mammals and counted. Exploration of landform and soil data was done using ArcGIS Toolbox functions and descriptive statistical analysis. The relationships between landforms, soils, small mammals and fleas were established by generalised linear regression model (GLM) operated in R statistics software. Results show that landforms and soils influence the abundance of small mammals and fleas and their spatial distribution. The abundance of small mammals and fleas increased with increase in elevation. Small mammal species richness also increases with elevation. A landform-soil model shows that available phosphorus, slope aspect and elevation were statistically significant predictors explaining richness and abundance of small mammals. Fleas' abundance and spatial distribution were influenced by hill-shade, available phosphorus and base saturation. The study suggests that landforms and soils have a strong influence on the richness and evenness of small mammals and their fleas' abundance hence could be used to explain plague dynamics in the area.

  10. Predicting small mammal and flea abundance using landform and soil properties in a plague endemic area in Lushoto District, Tanzania.

    PubMed

    Meliyo, Joel L; Kimaro, Didas N; Msanya, Balthazar M; Mulungu, Loth S; Hieronimo, Proches; Kihupi, Nganga I; Gulinck, Hubert; Deckers, Jozef A

    2014-07-01

    Small mammals particularly rodents, are considered the primary natural hosts of plague. Literature suggests that plague persistence in natural foci has a root cause in soils. The objective of this study was to investigate the relationship between on the one hand landforms and associated soil properties, and on the other hand small mammals and fleas in West Usambara Mountains in Tanzania, a plague endemic area. Standard field survey methods coupled with Geographical Information System (GIS) technique were used to examine landform and soils characteristics. Soil samples were analysed in the laboratory for physico-chemical properties. Small mammals were trapped on pre-established landform positions and identified to genus/species level. Fleas were removed from the trapped small mammals and counted. Exploration of landform and soil data was done using ArcGIS Toolbox functions and descriptive statistical analysis. The relationships between landforms, soils, small mammals and fleas were established by generalised linear regression model (GLM) operated in R statistics software. Results show that landforms and soils influence the abundance of small mammals and fleas and their spatial distribution. The abundance of small mammals and fleas increased with increase in elevation. Small mammal species richness also increases with elevation. A landform-soil model shows that available phosphorus, slope aspect and elevation were statistically significant predictors explaining richness and abundance of small mammals. Fleas' abundance and spatial distribution were influenced by hill-shade, available phosphorus and base saturation. The study suggests that landforms and soils have a strong influence on the richness and evenness of small mammals and their fleas' abundance hence could be used to explain plague dynamics in the area. PMID:26867276

  11. Effects of cattle grazing on small mammal communities in the Hulunber meadow steppe.

    PubMed

    Cao, Chan; Shuai, Ling-Ying; Xin, Xiao-Ping; Liu, Zhi-Tao; Song, Yan-Ling; Zeng, Zhi-Gao

    2016-01-01

    Small mammals play important roles in many ecosystems, and understanding their response to disturbances such as cattle grazing is fundamental for developing sustainable land use strategies. However, how small mammals respond to cattle grazing remains controversial. A potential cause is that most of previous studies adopt rather simple experimental designs based solely on the presence/absence of grazing, and are thus unable to detect any complex relationships between diversity and grazing intensity. In this study, we conducted manipulated experiments in the Hulunber meadow steppe to survey small mammal community structures under four levels of grazing intensities. We found dramatic changes in species composition in native small mammal communities when grazing intensity reached intermediate levels (0.46 animal unit/ha). As grazing intensity increased, Spermophilus dauricus gradually became the single dominant species. Species richness and diversity of small mammals in ungrazed and lightly grazed (0.23 animal unit/ha) area were much higher than in intermediately and heavily grazed area. We did not detect a humped relationship between small mammal diversity and disturbance levels predicted by the intermediate disturbance hypothesis (IDH). Our study highlighted the necessity of conducting manipulated experiments under multiple grazing intensities.

  12. Ongoing unraveling of a continental fauna: decline and extinction of Australian mammals since European settlement.

    PubMed

    Woinarski, John C Z; Burbidge, Andrew A; Harrison, Peter L

    2015-04-14

    The highly distinctive and mostly endemic Australian land mammal fauna has suffered an extraordinary rate of extinction (>10% of the 273 endemic terrestrial species) over the last ∼200 y: in comparison, only one native land mammal from continental North America became extinct since European settlement. A further 21% of Australian endemic land mammal species are now assessed to be threatened, indicating that the rate of loss (of one to two extinctions per decade) is likely to continue. Australia's marine mammals have fared better overall, but status assessment for them is seriously impeded by lack of information. Much of the loss of Australian land mammal fauna (particularly in the vast deserts and tropical savannas) has been in areas that are remote from human population centers and recognized as relatively unmodified at global scale. In contrast to general patterns of extinction on other continents where the main cause is habitat loss, hunting, and impacts of human development, particularly in areas of high and increasing human population pressures, the loss of Australian land mammals is most likely due primarily to predation by introduced species, particularly the feral cat, Felis catus, and European red fox, Vulpes vulpes, and changed fire regimes.

  13. Effects of cattle grazing on small mammal communities in the Hulunber meadow steppe

    PubMed Central

    Xin, Xiao-Ping; Liu, Zhi-Tao; Song, Yan-Ling

    2016-01-01

    Small mammals play important roles in many ecosystems, and understanding their response to disturbances such as cattle grazing is fundamental for developing sustainable land use strategies. However, how small mammals respond to cattle grazing remains controversial. A potential cause is that most of previous studies adopt rather simple experimental designs based solely on the presence/absence of grazing, and are thus unable to detect any complex relationships between diversity and grazing intensity. In this study, we conducted manipulated experiments in the Hulunber meadow steppe to survey small mammal community structures under four levels of grazing intensities. We found dramatic changes in species composition in native small mammal communities when grazing intensity reached intermediate levels (0.46 animal unit/ha). As grazing intensity increased, Spermophilus dauricus gradually became the single dominant species. Species richness and diversity of small mammals in ungrazed and lightly grazed (0.23 animal unit/ha) area were much higher than in intermediately and heavily grazed area. We did not detect a humped relationship between small mammal diversity and disturbance levels predicted by the intermediate disturbance hypothesis (IDH). Our study highlighted the necessity of conducting manipulated experiments under multiple grazing intensities. PMID:27635323

  14. Ongoing unraveling of a continental fauna: decline and extinction of Australian mammals since European settlement.

    PubMed

    Woinarski, John C Z; Burbidge, Andrew A; Harrison, Peter L

    2015-04-14

    The highly distinctive and mostly endemic Australian land mammal fauna has suffered an extraordinary rate of extinction (>10% of the 273 endemic terrestrial species) over the last ∼200 y: in comparison, only one native land mammal from continental North America became extinct since European settlement. A further 21% of Australian endemic land mammal species are now assessed to be threatened, indicating that the rate of loss (of one to two extinctions per decade) is likely to continue. Australia's marine mammals have fared better overall, but status assessment for them is seriously impeded by lack of information. Much of the loss of Australian land mammal fauna (particularly in the vast deserts and tropical savannas) has been in areas that are remote from human population centers and recognized as relatively unmodified at global scale. In contrast to general patterns of extinction on other continents where the main cause is habitat loss, hunting, and impacts of human development, particularly in areas of high and increasing human population pressures, the loss of Australian land mammals is most likely due primarily to predation by introduced species, particularly the feral cat, Felis catus, and European red fox, Vulpes vulpes, and changed fire regimes. PMID:25675493

  15. The impact of buffer strips and stream-side grazing on small mammals in southwestern Wisconsin

    USGS Publications Warehouse

    Chapman, Erik W.; Ribic, C.A.

    2002-01-01

    The practice of continuously grazing cattle along streams has caused extensive degradation of riparian habitats. Buffer strips and managed intensive rotational grazing (MIRG) have been proposed to protect and restore stream ecosystems in Wisconsin. However, the ecological implications of a switch from traditional livestock management to MIRG or buffer strip establishment have not been investigated. Differences in small mammal communities associated with riparian areas on continuously grazed and MIRG pastures, as well as vegetative buffer strips adjacent to row crops, were investigated in southwestern Wisconsin during May-September 1997 and 1998. More species (mean of 6-7) were found on the buffer sites than on the pasture sites (mean of 2-5). Total small mammal abundance on buffer sites was greater than on the pastures as well: there were 3-5 times as many animals on the buffer sites compared to the pasture sites, depending on year. There were no differences in species richness or total abundance between MIRG and continuously grazed pastures in either year. Total small mammal abundance was greater near the stream than away from the stream, regardless of farm management practice but there were no differences in species richness. Buffer strips appear to support a particularly rich and abundant small mammal community. Although results did not detect a difference in small mammal use between pasture types, farm-wide implications of a conversion from continuous to MIRG styles of grazing may benefit small mammals indirectly by causing an increase in the prevalence of pasture in the agricultural landscape.

  16. Ongoing unraveling of a continental fauna: Decline and extinction of Australian mammals since European settlement

    PubMed Central

    Woinarski, John C. Z.; Burbidge, Andrew A.; Harrison, Peter L.

    2015-01-01

    The highly distinctive and mostly endemic Australian land mammal fauna has suffered an extraordinary rate of extinction (>10% of the 273 endemic terrestrial species) over the last ∼200 y: in comparison, only one native land mammal from continental North America became extinct since European settlement. A further 21% of Australian endemic land mammal species are now assessed to be threatened, indicating that the rate of loss (of one to two extinctions per decade) is likely to continue. Australia’s marine mammals have fared better overall, but status assessment for them is seriously impeded by lack of information. Much of the loss of Australian land mammal fauna (particularly in the vast deserts and tropical savannas) has been in areas that are remote from human population centers and recognized as relatively unmodified at global scale. In contrast to general patterns of extinction on other continents where the main cause is habitat loss, hunting, and impacts of human development, particularly in areas of high and increasing human population pressures, the loss of Australian land mammals is most likely due primarily to predation by introduced species, particularly the feral cat, Felis catus, and European red fox, Vulpes vulpes, and changed fire regimes. PMID:25675493

  17. Effects of cattle grazing on small mammal communities in the Hulunber meadow steppe.

    PubMed

    Cao, Chan; Shuai, Ling-Ying; Xin, Xiao-Ping; Liu, Zhi-Tao; Song, Yan-Ling; Zeng, Zhi-Gao

    2016-01-01

    Small mammals play important roles in many ecosystems, and understanding their response to disturbances such as cattle grazing is fundamental for developing sustainable land use strategies. However, how small mammals respond to cattle grazing remains controversial. A potential cause is that most of previous studies adopt rather simple experimental designs based solely on the presence/absence of grazing, and are thus unable to detect any complex relationships between diversity and grazing intensity. In this study, we conducted manipulated experiments in the Hulunber meadow steppe to survey small mammal community structures under four levels of grazing intensities. We found dramatic changes in species composition in native small mammal communities when grazing intensity reached intermediate levels (0.46 animal unit/ha). As grazing intensity increased, Spermophilus dauricus gradually became the single dominant species. Species richness and diversity of small mammals in ungrazed and lightly grazed (0.23 animal unit/ha) area were much higher than in intermediately and heavily grazed area. We did not detect a humped relationship between small mammal diversity and disturbance levels predicted by the intermediate disturbance hypothesis (IDH). Our study highlighted the necessity of conducting manipulated experiments under multiple grazing intensities. PMID:27635323

  18. Scenarios of large mammal loss in Europe for the 21st century.

    PubMed

    Rondinini, Carlo; Visconti, Piero

    2015-08-01

    Distributions and populations of large mammals are declining globally, leading to an increase in their extinction risk. We forecasted the distribution of extant European large mammals (17 carnivores and 10 ungulates) based on 2 Rio+20 scenarios of socioeconomic development: business as usual and reduced impact through changes in human consumption of natural resources. These scenarios are linked to scenarios of land-use change and climate change through the spatial allocation of land conversion up to 2050. We used a hierarchical framework to forecast the extent and distribution of mammal habitat based on species' habitat preferences (as described in the International Union for Conservation of Nature Red List database) within a suitable climatic space fitted to the species' current geographic range. We analyzed the geographic and taxonomic variation of habitat loss for large mammals and the potential effect of the reduced impact policy on loss mitigation. Averaging across scenarios, European large mammals were predicted to lose 10% of their habitat by 2050 (25% in the worst-case scenario). Predicted loss was much higher for species in northwestern Europe, where habitat is expected to be lost due to climate and land-use change. Change in human consumption patterns was predicted to substantially improve the conservation of habitat for European large mammals, but not enough to reduce extinction risk if species cannot adapt locally to climate change or disperse.

  19. Blood flow to long bones indicates activity metabolism in mammals, reptiles and dinosaurs.

    PubMed

    Seymour, Roger S; Smith, Sarah L; White, Craig R; Henderson, Donald M; Schwarz-Wings, Daniela

    2012-02-01

    The cross-sectional area of a nutrient foramen of a long bone is related to blood flow requirements of the internal bone cells that are essential for dynamic bone remodelling. Foramen area increases with body size in parallel among living mammals and non-varanid reptiles, but is significantly larger in mammals. An index of blood flow rate through the foramina is about 10 times higher in mammals than in reptiles, and even higher if differences in blood pressure are considered. The scaling of foramen size correlates well with maximum whole-body metabolic rate during exercise in mammals and reptiles, but less well with resting metabolic rate. This relates to the role of blood flow associated with bone remodelling during and following activity. Mammals and varanid lizards have much higher aerobic metabolic rates and exercise-induced bone remodelling than non-varanid reptiles. Foramen areas of 10 species of dinosaur from five taxonomic groups are generally larger than from mammals, indicating a routinely highly active and aerobic lifestyle. The simple measurement holds possibilities offers the possibility of assessing other groups of extinct and living vertebrates in relation to body size, behaviour and habitat.

  20. Accumulation of slightly deleterious mutations in mitochondrial protein-coding genes of large versus small mammals

    PubMed Central

    Popadin, Konstantin; Polishchuk, Leonard V.; Mamirova, Leila; Knorre, Dmitry; Gunbin, Konstantin

    2007-01-01

    After the effective size of a population, Ne, declines, some slightly deleterious amino acid replacements which were initially suppressed by purifying selection become effectively neutral and can reach fixation. Here we investigate this phenomenon for a set of all 13 mitochondrial protein-coding genes from 110 mammalian species. By using body mass as a proxy for Ne, we show that large mammals (i.e., those with low Ne) as compared with small ones (in our sample these are, on average, 369.5 kg and 275 g, respectively) have a 43% higher rate of accumulation of nonsynonymous nucleotide substitutions relative to synonymous substitutions, and an 8–40% higher rate of accumulation of radical amino acid substitutions relative to conservative substitutions, depending on the type of amino acid classification. These higher rates result in a 6% greater amino acid dissimilarity between modern species and their most recent reconstructed ancestors in large versus small mammals. Because nonsynonymous substitutions are likely to be more harmful than synonymous substitutions, and radical amino acid substitutions are likely to be more harmful than conservative ones, our results suggest that large mammals experience less efficient purifying selection than small mammals. Furthermore, because in the course of mammalian evolution body size tends to increase and, consequently, Ne tends to decline, evolution of mammals toward large body size may involve accumulation of slightly deleterious mutations in mitochondrial protein-coding genes, which may contribute to decline or extinction of large mammals. PMID:17679693

  1. Effects of cattle grazing on small mammal communities in the Hulunber meadow steppe

    PubMed Central

    Xin, Xiao-Ping; Liu, Zhi-Tao; Song, Yan-Ling

    2016-01-01

    Small mammals play important roles in many ecosystems, and understanding their response to disturbances such as cattle grazing is fundamental for developing sustainable land use strategies. However, how small mammals respond to cattle grazing remains controversial. A potential cause is that most of previous studies adopt rather simple experimental designs based solely on the presence/absence of grazing, and are thus unable to detect any complex relationships between diversity and grazing intensity. In this study, we conducted manipulated experiments in the Hulunber meadow steppe to survey small mammal community structures under four levels of grazing intensities. We found dramatic changes in species composition in native small mammal communities when grazing intensity reached intermediate levels (0.46 animal unit/ha). As grazing intensity increased, Spermophilus dauricus gradually became the single dominant species. Species richness and diversity of small mammals in ungrazed and lightly grazed (0.23 animal unit/ha) area were much higher than in intermediately and heavily grazed area. We did not detect a humped relationship between small mammal diversity and disturbance levels predicted by the intermediate disturbance hypothesis (IDH). Our study highlighted the necessity of conducting manipulated experiments under multiple grazing intensities.

  2. Scenarios of large mammal loss in Europe for the 21st century.

    PubMed

    Rondinini, Carlo; Visconti, Piero

    2015-08-01

    Distributions and populations of large mammals are declining globally, leading to an increase in their extinction risk. We forecasted the distribution of extant European large mammals (17 carnivores and 10 ungulates) based on 2 Rio+20 scenarios of socioeconomic development: business as usual and reduced impact through changes in human consumption of natural resources. These scenarios are linked to scenarios of land-use change and climate change through the spatial allocation of land conversion up to 2050. We used a hierarchical framework to forecast the extent and distribution of mammal habitat based on species' habitat preferences (as described in the International Union for Conservation of Nature Red List database) within a suitable climatic space fitted to the species' current geographic range. We analyzed the geographic and taxonomic variation of habitat loss for large mammals and the potential effect of the reduced impact policy on loss mitigation. Averaging across scenarios, European large mammals were predicted to lose 10% of their habitat by 2050 (25% in the worst-case scenario). Predicted loss was much higher for species in northwestern Europe, where habitat is expected to be lost due to climate and land-use change. Change in human consumption patterns was predicted to substantially improve the conservation of habitat for European large mammals, but not enough to reduce extinction risk if species cannot adapt locally to climate change or disperse. PMID:25999066

  3. Predator-induced synchrony in population oscillations of coexisting small mammal species

    PubMed Central

    Korpimäki, Erkki; Norrdahl, Kai; Huitu, Otso; Klemola, Tero

    2005-01-01

    Comprehensive analyses of long-term (1977–2003) small-mammal abundance data from western Finland showed that populations of Microtus voles (field voles M. agrestis and sibling voles M. rossiaemeridionalis) voles, bank (Clethrionomys glareolus) and common shrews (Sorex araneus) fluctuated synchronously in 3 year population cycles. Time-series analyses indicated that interspecific synchrony is influenced strongly by density-dependent processes. Synchrony among Microtus and bank voles appeared additionally to be influenced by density-independent processes. To test whether interspecific synchronization through density-dependent processes is caused by predation, we experimentally reduced the densities of the main predators of small mammals in four large agricultural areas, and compared small mammal abundances in these to those in four control areas (2.5–3 km2) through a 3 year small-mammal population cycle. Predator reduction increased densities of the main prey species, Microtus voles, in all phases of the population cycle, while bank voles, the most important alternative prey of predators, responded positively only in the low and the increase phase. Manipulation also increased the autumn densities of water voles (Arvicola terrestris) in the increase phase of the cycle. No treatment effects were detected for common shrews or mice. Our results are in accordance with the alternative prey hypothesis, by which predators successively reduce the densities of both main and alternative prey species after the peak phase of small-mammal population cycles, thus inducing a synchronous low phase. PMID:15695211

  4. Molecular evidence for a single taxon, Anopheles nuneztovari s. l., from two endemic malaria regions in Colombia

    PubMed Central

    Jaramillo, Luz Marina; Gutiérrez, Lina A; Luckhart, Shirley; Conn, Jan E; Correa, Margarita M

    2012-01-01

    To elucidate the Anopheles nuneztovari s.l. taxonomic status at a microgeographic level in four malaria endemic localities from Antioquia and Córdoba, Colombia, fragments of the Cytochrome oxidase subunit I (COI) and the white gene were used. The COI analysis showed low genetic differentiation with FST levels between −0.02 and 0.137 and Nm values between 3 and infinity, indicating the presence of high gene flow among An. nuneztovari s.l. populations from the four localities. The COI network showed a single most common haplotype, 1 (n=55), present in all localities, as the likely ancestral haplotype. Analysis of the white gene showed that An. nuneztovari s.l. populations from both departments grouped with haplotypes 19 and 20, which are part of lineage 3 previously reported. The results of the present study suggest that An. nuneztovari s.l. is a single taxon in the area of the present study. PMID:22241127

  5. Challenges to natural resource monitoring in a small border park: terrestrial mammals at Coronado National Memorial, Cochise County, Arizona

    USGS Publications Warehouse

    Swann, Don E.; Bucci, Melanie; Kuenzi, Amy J.; Alberti, Barbara N.; Schwalbe, Cecil R.; Halvorson, William L.; van Riper, Charles; Schwalbe, Cecil R.

    2010-01-01

    Long-term monitoring in national parks is essential to meet National Park Service and other important public goals. Terrestrial mammals are often proposed for monitoring because large mammals are of interest to visitors and small mammals are important as prey. However, traditional monitoring strategies for mammals are often too expensive and complex to sustain for long periods, particularly in small parks. To evaluate potential strategies for long-term monitoring in small parks, we conducted an intensive one-year inventory of terrestrial mammals at Coronado National Memorial, located in Arizona on the U.S.-Mexico international border, then continued less-intensive monitoring at the site for 7 additional years. During 1996-2003 we confirmed 44 species of terrestrial mammals. Most species (40) were detected in the intensive first year of the study, but we continued to detect new species in later years. Mark-recapture data on small mammals indicated large inter-annual fluctuations in population size, but no significant trend over the 7-year period. Issues associated with the international border affected monitoring efforts and increased sampling costs. Our study confirms that sustained annual monitoring of mammals is probably not feasible in small park units like Coronado. However, comparisons of our data with past studies provide insight into important changes in the mammal community since the 1970s, including an increase in abundance and diversity of grassland rodents. Our results suggest that intensive inventories every 10-20 years may be a valuable and cost-effective approach for detecting long-term trends in terrestrial mammal communities in small natural areas.

  6. Conservation strategies for Africa's large mammals.

    PubMed

    Hanks, J

    2001-01-01

    Africa's large mammals are conserved for their aesthetic, scientific and economic values. Many of these species face a gloomy future precipitated by a combination of factors directly and indirectly influenced by the activities of man, including habitat loss, overexploitation, poor management of designated protected areas, and the vulnerability of small isolated populations. Africa's designated protected areas and biodiversity hotspots are also under threat, highlighting the importance of embracing community participation to address accelerating poverty and malnutrition. Innovative strategies are required for the conservation of Africa's mammals, such as the integration of a wide range of species in the production landscape, including the farming community. Transfrontier conservation areas (TFCAs) have been established with the combined objectives of conserving biodiversity, creating new jobs in the tourism and wildlife industry, and promoting a culture of peace. These areas extend far beyond traditional national parks, providing opportunities for integrating large mammals into sustainable land-use practices, at the same time as addressing some of the continent's more pressing socioeconomic needs. Research on African mammals will inevitably have to change direction to accommodate the growing threats and changed circumstances. Priorities will include the identification of corridors associated with TFCA establishment, the determination of the economic value of certain species in consumptive use programmes, research on contraception as a management option in restricted areas, and further work on the indirect use value of species. There will also be worthwhile opportunities to be pursued with ex situ conservation programmes, but these need to be focussed more efficiently.

  7. Mammals of the Savannah River Site

    SciTech Connect

    Cothran, E.G.; Smith, M.H.; Wolff, J.O.; Gentry, J.B.

    1991-01-01

    This book is designed to be used as a field guide, reference book, bibliography, and introduction to the basic biology and ecology of the 54 mammal species that currently or potentially exist on or near the Savannah River Site (SRS). For 50 of these species, we present basic descriptions, distinguishing morphological features, distribution and habitat preferences, food habits, reproductive biology, social behavior, ecological relationships with other species, and economic importance to man. For those species that have been studied on the SRS, we summarize the results of these studies. Keys and illustrations are provided for whole body and skull identification. A selected glossary defines technical terminology. Illustrations of tracks of the more common larger mammals will assist in field identifications. We also summarize the results of two major long-term SRS studies, The Forbearer Census'' and White-tailed Deer Studies''. A cross-indexed list of over 300 SRS publications on mammals classifies each publication by 23 categories such as habitat, reproduction, genetics, etc., and also for each mammal species. The 149 Master's theses and Ph.D. dissertations that have been conducted at the Savannah River Ecology Laboratory are provided as additional references.

  8. Mammals of the Savannah River Site

    SciTech Connect

    Cothran, E.G.; Smith, M.H.; Wolff, J.O.; Gentry, J.B.

    1991-12-31

    This book is designed to be used as a field guide, reference book, bibliography, and introduction to the basic biology and ecology of the 54 mammal species that currently or potentially exist on or near the Savannah River Site (SRS). For 50 of these species, we present basic descriptions, distinguishing morphological features, distribution and habitat preferences, food habits, reproductive biology, social behavior, ecological relationships with other species, and economic importance to man. For those species that have been studied on the SRS, we summarize the results of these studies. Keys and illustrations are provided for whole body and skull identification. A selected glossary defines technical terminology. Illustrations of tracks of the more common larger mammals will assist in field identifications. We also summarize the results of two major long-term SRS studies, ``The Forbearer Census`` and ``White-tailed Deer Studies``. A cross-indexed list of over 300 SRS publications on mammals classifies each publication by 23 categories such as habitat, reproduction, genetics, etc., and also for each mammal species. The 149 Master`s theses and Ph.D. dissertations that have been conducted at the Savannah River Ecology Laboratory are provided as additional references.

  9. [Current views on vision of mammals].

    PubMed

    Khokhlova, T V

    2012-01-01

    In the review, research data are presented on mammals' vision including visual pigments, color and contrast vision, and visual behaviour in different species. It is shown that in course of evolution mammals were gradually losing the elements of daylight cone vision system that are typical of other vertebrates. In monotremes, visual pigments SWS2 (cone blue-sensitive 2) and MWS/LWS (green/red-sensitive) are still present, as well as rod RH1. Theria, except some primates, also have two cone visual pigments: SWS1 (ultraviolet/violet or blue-sensitive 1) and MWS/LWS along with rod RH1. Humans and some other higher primates evolved the new visual pigment, MWS, and acquired trichromatic vision. Marine mammals (cetaceans and pinnipeds) and some species of other orders have lost also the visual pigment SWS1, probably due to specificity of processing the information received by these cones. Current view on mammals' vision with two cone pigments and rods is presented. Data on maximum spectral sensitivity of visual pigments in different species and orders are given along with data on spatial contrast sensation. High visual acuity has been acquired by ungulates, artiodactyls, and primates, while the highest one--by humans with their specialized fovea. PMID:23330397

  10. [Current views on vision of mammals].

    PubMed

    Khokhlova, T V

    2012-01-01

    In the review, research data are presented on mammals' vision including visual pigments, color and contrast vision, and visual behaviour in different species. It is shown that in course of evolution mammals were gradually losing the elements of daylight cone vision system that are typical of other vertebrates. In monotremes, visual pigments SWS2 (cone blue-sensitive 2) and MWS/LWS (green/red-sensitive) are still present, as well as rod RH1. Theria, except some primates, also have two cone visual pigments: SWS1 (ultraviolet/violet or blue-sensitive 1) and MWS/LWS along with rod RH1. Humans and some other higher primates evolved the new visual pigment, MWS, and acquired trichromatic vision. Marine mammals (cetaceans and pinnipeds) and some species of other orders have lost also the visual pigment SWS1, probably due to specificity of processing the information received by these cones. Current view on mammals' vision with two cone pigments and rods is presented. Data on maximum spectral sensitivity of visual pigments in different species and orders are given along with data on spatial contrast sensation. High visual acuity has been acquired by ungulates, artiodactyls, and primates, while the highest one--by humans with their specialized fovea.

  11. Mammal assemblages in forest fragments and landscapes occupied by black howler monkeys.

    PubMed

    Rangel-Negrín, Ariadna; Coyohua-Fuentes, Alejandro; Canales-Espinosa, Domingo; Dias, Pedro Américo D

    2014-07-01

    Species assemblages in disturbed habitats vary as a function of the interaction between species requirements and the spatial configuration of the habitat. There are many reports accounting for the presence of howler monkeys in fragments where other mammals are absent, suggesting that they are more resilient. In the present study we explored this idea and predicted that if howler monkeys were more resilient to habitat loss and fragmentation than other mammals, mammal assemblages in fragments occupied by howler monkeys should include fewer species with decreasing amount of habitat (smaller fragment size and less habitat in the landscape) and increasing number of forest fragments. We explored these relationships by additionally considering the feeding and life habits of mammal species, as well as the isolation and proximity of each fragment to human settlements and roads. We sampled the presence of mammals in five fragments occupied by black howler monkeys (Alouatta pigra) in the Mexican state of Campeche. Through direct sights performed during 240 h in each fragment, we observed 23 species. At the landscape scale, higher fragmentation was associated with a decrease in herbivores, omnivores and total number of species. At the fragment scale semiarboreal, omnivore, and total number of species increased with increasing fragment size. This study supports the idea that howler monkeys are more resilient to forest loss and fragmentation than other native mammals, and our exploratory analyses suggest that the specific mammal assemblages that are found in fragments are related to both landscape and fragment scale spatial attributes, as well as with species-specific characteristics.

  12. Avian sleep homeostasis: convergent evolution of complex brains, cognition and sleep functions in mammals and birds.

    PubMed

    Rattenborg, Niels C; Martinez-Gonzalez, Dolores; Lesku, John A

    2009-03-01

    Birds are the only taxonomic group other than mammals that exhibit high-amplitude slow-waves in the electroencephalogram (EEG) during sleep. This defining feature of slow-wave sleep (SWS) apparently evolved independently in mammals and birds, as reptiles do not exhibit similar EEG activity during sleep. In mammals, the level of slow-wave activity (SWA) (low-frequency spectral power density) during SWS increases and decreases as a function of prior time spent awake and asleep, respectively, and therefore reflects homeostatically regulated sleep processes potentially tied to the function of SWS. Although birds also exhibit SWS, previous sleep deprivation studies in birds did not detect a compensatory increase in SWS-related SWA during recovery, as observed in similarly sleep-deprived mammals. This suggested that, unlike mammalian SWS, avian SWS is not homeostatically regulated, and therefore might serve a different function. However, we recently demonstrated that SWA during SWS increases in pigeons following short-term sleep deprivation. Herein we summarize research on avian sleep homeostasis, and cast our evidence for this phenomenon within the context of theories for the function of SWS in mammals. We propose that the convergent evolution of homeostatically regulated SWS in mammals and birds was directly linked to the convergent evolution of large, heavily interconnected brains capable of performing complex cognitive processes in each group. Specifically, as has been proposed for mammals, the interconnectivity that forms the basis of complex cognition in birds may also instantiate slow, synchronous network oscillations during SWS that in turn maintain interconnectivity and cognition at an optimal level.

  13. Taxon-rich phylogenomic analyses resolve the eukaryotic tree of life and reveal the power of subsampling by sites.

    PubMed

    Katz, Laura A; Grant, Jessica R

    2015-05-01

    Most eukaryotic lineages are microbial, and many have only recently been sampled for phylogenetic studies or remain in the "dark area" of the tree of life where there are no molecular data. To assess relationships among eukaryotic lineages, we perform a taxon-rich phylogenomic analysis including 232 eukaryotes selected to maximize taxonomic diversity and up to 1554 genes chosen as vertically inherited based on their broad distribution among eukaryotes. We also include sequences from 486 bacteria and 84 archaea to assess the impact of endosymbiotic gene transfer (EGT) from plastids and to detect contamination. Overall, our analyses are consistent with other less taxon-rich estimates of the eukaryotic tree of life, and we recover strong support for five major clades: Amoebozoa, Excavata (without the genus Malawimonas), Opisthokonta, Archaeplastida, and SAR (Stramenopila, Alveolata, and Rhizaria). Our analyses also highlight the existence of "orphan" lineages, lineages that lack robust placement in the eukaryotic tree of life, and indicate the possibility of as yet undiscovered diversity. In analyses including bacteria and archaea, we find that approximately 10% of the 1554 genes, which we choose because they are found in four or five of the five major eukaryotic clades and hence may be more likely to be inherited vertically, appear to have been acquired from cyanobacteria through EGT in photosynthetic lineages. Removing these EGT genes places the green algae as sister to the glaucophytes instead of the red algae, suggesting that unknowingly including genes of plastid origin, and combining them with genes of nuclear origin, may mislead phylogenetic estimates. Finally, the large size of our data set allows comparative analyses of subsets of data; alignments built from randomly sampled sites provide greater support, particularly for deep relationships, than do equivalent-sized data sets built from randomly sampled genes.

  14. Effects of roads on small mammals

    USGS Publications Warehouse

    Adams, L.W.; Geis, A.D.

    1983-01-01

    (1) The study was designed to determine the effects of roads on the diversity, spatial distribution, and density of small mammals. (2) Forty species of small mammal (5859 individuals) were snap-trapped in the study. Data resulted from 144 360 trap-nights of effort for an average of 4.06 captures per 100 trap-nights. (3) Small mammal community structure and density were both influenced by roads. Community structure in right-of-way (ROW) habitat was different from that in adjacent habitat. Five species did not prefer ROW habitat: the golden mouse, dusky-footed woodrat, brush mouse, pinon mouse, and California red-backed vole. However, there were more species present in ROW habitat than in adjacent habitat. Grassland species generally preferred ROW habitat and many less habitat-specific species were distributed in ROW and adjacent habitat. (4) Small mammal density (all species combined) was greater in interstate ROW habitat than in adjacent habitat. This was also true individually for the eastern harvest mouse, white-footed mouse, meadow vole, prairie vole, vagrant shrew. Townsend's vole, and California vole. Small mammal density was less in county road ROWs than in adjacent habitat, probably because of the small size of these areas. The data indicate that ROW habitat and its accompanying edge are attractive no: only to grassland species but also to many less habitat-specific species that make use of the ROW-edge-adjacent habitat complex. (5) Mortality on interstate highways was greatest for those species with highest densities in ROW habitat, and did not appear to be detrimental to populations of these species.

  15. 75 FR 20344 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Rocket Launches from...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ... Marine Mammals Incidental to Rocket Launches from Kodiak, AK AGENCY: National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Commerce. ACTION: Notice; Issuance of a Letter of... (Eumetopias jubatus) and Pacific harbor seals (Phoca vitulina richardsi) incidental to rocket launches...

  16. 78 FR 77433 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-23

    ... one elephant seal has been observed at Pigeon Point. California Sea Lion California sea lions are not... to PISCO to take marine mammals incidental to these same proposed activities (77 FR 72327, December...

  17. 75 FR 49465 - Marine Mammals; File No. 14682

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ... Register (74 FR 58243) that a request for a permit to conduct scientific research on marine mammals had... Whitlow Au, Ph.D., University of Hawaii, Hawaii Institute of Marine Biology, Marine Mammal...

  18. 76 FR 7824 - Marine Mammals; File No. 978-1791

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... importing of marine mammals (50 CFR part 216). The original permit, issued on February 9, 2006 (71 FR 8279...D, Marine Mammal Research Program Hawaii Institute of Marine Biology, P.O. Box 1106, Kailua,...

  19. Effects of tillage practices and carbofuran exposure on small mammals

    USGS Publications Warehouse

    Albers, P.H.; Linder, G.; Nichols, J.D.

    1990-01-01

    We compared population estimates, body mass, movement, and blood chemistry of small mammals between conventionally tilled and no-till cornfields in Maryland and Pennsylvania to evaluate the effects of tillage practices and carbofuran exposure on small mammals.

  20. 78 FR 57133 - Marine Mammals; File No. 14514

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-17

    ... July 28, 2010 (75 FR 50748), authorizes the University of Florida to receive, import, and export marine... studies; development of a marine mammal histology database and atlas and marine mammal cell lines;...

  1. 75 FR 50748 - Marine Mammals; File No. 14514

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-17

    ... Federal Register (75 FR 23241) that a request for a permit to import and export marine mammal parts for... histology database and atlas and marine mammal cell lines; and comparative morphology studies. The permit...

  2. 75 FR 23241 - Marine Mammals; File No. 14514

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-03

    ... brevetoxin studies; develop a marine mammal histology database and atlas, marine mammal cell lines; and... subject line of the email comment. Those individuals requesting a public hearing should submit a...

  3. [Fleas of small mammals from the northeastern Russian Far East].

    PubMed

    Medvedev, S G; Dokuchaev, N E; Tret'iakov, K A; Iamborko, A V; Kiselev, S V

    2014-01-01

    Results of the study of fleas (Siphonaptera) collected from small mammals (insectivores and rodents) in the Russian Far East (Magadan Province, and Khabarovsk and Kamchatka Territories) are represented. Fourteen flea species were revealed in 17 species of small mammals.

  4. Modeling the effects of fire severity and spatial complexity on Small Mammals in Yosemite National Park, California

    USGS Publications Warehouse

    Roberts, Susan L.; Van Wagtendonk, Jan W.; Miles, A. Keith; Kelt, Douglas A.; Lutz, James A.

    2008-01-01

    We evaluated the impact of fire severity and related spatial and vegetative parameters on small mammal populations in 2 yr- to 15 yr-old burns in Yosemite National Park, California, USA. We also developed habitat models that would predict small mammal responses to fires of differing severity. We hypothesized that fire severity would influence the abundances of small mammals through changes in vegetation composition, structure, and spatial habitat complexity. Deer mouse (Peromyscus maniculatus) abundance responded negatively to fire severity, and brush mouse (P. boylii) abundance increased with increasing oak tree (Quercus spp.) cover. Chipmunk (Neotamias spp.) abundance was best predicted through a combination of a negative response to oak tree cover and a positive response to spatial habitat complexity. California ground squirrel (Spermophilus beecheyi) abundance increased with increasing spatial habitat complexity. Our results suggest that fire severity, with subsequent changes in vegetation structure and habitat spatial complexity, can influence small mammal abundance patterns.

  5. Evolution and Coevolution of PRC2 Genes in Vertebrates and Mammals.

    PubMed

    Liu, Xi; Yang, Jingwen; Wu, Nan; Song, Ruixian; Zhu, Hao

    2015-01-01

    Recruited by noncoding RNAs (ncRNAs) to specific genomic sites, polycomb repressive complexes 2 (PRC2) modify chromatin states in nearly all eukaryotes. The limited ncRNAs in Drosophila but abundant in mammals should have made PRC2 genes evolved significantly in Deuterostomia to adapt to the much increased ncRNAs. This study analyzes the evolution and coevolution of seven PRC2 genes in 29 Deuterostomia. These genes, previously assumed highly conserved, are found to have obtained multiple insertions in vertebrates and mammals and undergone significant positive selections in marsupials and prosimians, indicating adaptions to substantially increased lncRNAs (long noncoding RNAs) in mammals and in primates. Some insertions occur notably in homologous sequences of human nonsense-mediated decay (NMD) transcripts. Moreover, positive selections and signals of convergent evolution imply the independent increase of lncRNAs in mammals and in primates. Coevolutionary analysis reveals that patterns of interaction between PRC2 proteins have also much evolved from vertebrates to mammals, indicating adaptation at the protein complex level. The potential functions of mammalian-specific insertions and NMD transcripts deserve further experimental examination.

  6. Comparative seroprevalence of Leptospira interrogans in Colombian mammals along a climatic gradient.

    PubMed

    Astudillo, Viviana González; Hernández, Dave Wehdeking; Stadlin, Juliana Peña; Bernal, Leonardo Arias; Rodríguez, Dora Adriana Lombo; Hernández, Miryam Astudillo

    2012-12-01

    Leptospirosis is a widespread zoonotic disease with well-established impacts on human health in tropical and subtropical regions. Although Leptospira spp. are known to readily infect many wildlife species, the understanding of interspecies and climatic variability in patterns of infection in Neotropical mammals is limited. To improve the understanding of this interplay, 85 mammals representing 17 species were sampled from four Colombian zoos along a climatic gradient. Prevalence of the 21 primary serovars against Leptospira interrogans was determined using the microagglutination test. Individuals were considered positive for a given serovar if antibodies were observable at a 1:100 dilution or greater. Overall prevalence was 9.52%, with positive titers to serovar hurstbridge in Carnivora (Canidae); serovar sarmin in Primata (Atelidae); and serovars australis, mini, autumnalis, pomona, icterohaemorrhagiae, and seramanga in Primata (Cebidae). Prevalence was positively correlated with humidity and temperature, with significantly higher prevalence at the site characterized by high humidity, severe flooding because of rainfall, and warm weather throughout the year. All positive animals were classified as clinically asymptomatic, meaning that antibodies from a current or past infection were detected but no overt symptoms were apparent. The diversity of serovars observed and the taxon-specific nature of these associations suggest that the epidemiology of Leptospira transmission is likely to be complex and multidimensional. The strong association observed between prevalence and climate suggests that the important role of climate as an indicator of Leptospira infection risk in humans may also be applicable to wildlife. Future studies in both wild and captive populations of Neotropical wildlife will further elucidate this disease interplay. PMID:23272343

  7. Molecular adaptation of telomere associated genes in mammals

    PubMed Central

    2013-01-01

    Background Placental mammals display a huge range of life history traits, including size, longevity, metabolic rate and germ line generation time. Although a number of general trends have been proposed between these traits, there are exceptions that warrant further investigation. Species such as naked mole rat, human and certain bat species all exhibit extreme longevity with respect to body size. It has long been established that telomeres and telomere maintenance have a clear role in ageing but it has not yet been established whether there is evidence for adaptation in telomere maintenance proteins that could account for increased longevity in these species. Results Here we carry out a molecular investigation of selective pressure variation, specifically focusing on telomere associated genes across placental mammals. In general we observe a large number of instances of positive selection acting on telomere genes. Although these signatures of selection overall are not significantly correlated with either longevity or body size we do identify positive selection in the microbat species Myotis lucifugus in functionally important regions of the telomere maintenance genes DKC1 and TERT, and in naked mole rat in the DNA repair gene BRCA1. Conclusion These results demonstrate the multifarious selective pressures acting across the mammal phylogeny driving lineage-specific adaptations of telomere associated genes. Our results show that regardless of the longevity of a species, these proteins have evolved under positive selection thereby removing increased longevity as the single selective force driving this rapid rate of evolution. However, evidence of molecular adaptations specific to naked mole rat and Myotis lucifugus highlight functionally significant regions in genes that may alter the way in which telomeres are regulated and maintained in these longer-lived species. PMID:24237966

  8. 50 CFR 16.11 - Importation of live wild mammals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 1 2011-10-01 2011-10-01 false Importation of live wild mammals. 16.11... mammals. (a) The importation, transportation, or acquisition is prohibited of live specimens of: (1) Any... mammals under the terms and conditions set forth in § 16.22. (b) Upon the filing of a written...

  9. 77 FR 26513 - Marine Mammals; File No. 15777

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-04

    ... National Oceanic and Atmospheric Administration RIN 0648-XC014 Marine Mammals; File No. 15777 AGENCY... to take marine mammals during scientific research in coastal waters and adjacent waters off the... under the authority of the Marine Mammal Protection Act of 1972, as amended (MMPA; 16 U.S.C. 1361 et...

  10. 77 FR 19646 - Marine Mammals; File No. 17178

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    ... National Oceanic and Atmospheric Administration RIN 0648-XB139 Marine Mammals; File No. 17178 AGENCY... permit to import marine mammal parts for scientific research. DATES: Written, telefaxed, or email.... SUPPLEMENTARY INFORMATION: The subject permit is requested under the authority of the Marine Mammal...

  11. 77 FR 19645 - Marine Mammals; File No. 16111

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    ... National Oceanic and Atmospheric Administration RIN 0648-XA626 Marine Mammals; File No. 16111 AGENCY... form for a permit to conduct research on marine mammals. DATES: Written, telefaxed, or email comments... Mammal Protection Act of 1972, as amended (MMPA; 16 U.S.C. 1361 et seq.), the regulations governing...

  12. 75 FR 16076 - Marine Mammals; File No. 15206

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-31

    ... National Oceanic and Atmospheric Administration RIN 0648-XV57 Marine Mammals; File No. 15206 AGENCY... of the Marine Mammal Protection Act of 1972, as amended (16 U.S.C. 1361 et seq.), and the regulations governing the taking and importing of marine mammals (50 CFR part 216). The applicant requests...

  13. 77 FR 32081 - Marine Mammals; File No. 17236

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-31

    ... National Oceanic and Atmospheric Administration RIN 0648-XC050 Marine Mammals; File No. 17236 AGENCY.... SUPPLEMENTARY INFORMATION: The subject permit is requested under the authority of the Marine Mammal Protection... importing of marine mammals (50 CFR part 216). The purpose of the research is to evaluate how...

  14. 77 FR 60107 - Marine Mammals; File No. 17298

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-02

    ... National Oceanic and Atmospheric Administration RIN 0648-XC218 Marine Mammals; File No. 17298 AGENCY..., Connecticut 06355 , has applied in due form for a permit to collect, import, export, and receive marine mammal... requested under the authority of the Marine Mammal Protection Act of 1972, as amended (MMPA; 16 U.S.C....

  15. 50 CFR 16.11 - Importation of live wild mammals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Importation of live wild mammals. 16.11... mammals. (a) The importation, transportation, or acquisition is prohibited of live specimens of: (1) Any... mammals under the terms and conditions set forth in § 16.22. (b) Upon the filing of a written...

  16. 77 FR 268 - Marine Mammals; File No. 16998

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-04

    ... National Oceanic and Atmospheric Administration RIN 0648-XA914 Marine Mammals; File No. 16998 AGENCY... under the authority of the Marine Mammal Protection Act of 1972, as amended (MMPA; 16 U.S.C. 1361 et seq.), the regulations governing the taking and importing of marine mammals (50 CFR part 216), the...

  17. 76 FR 34053 - Marine Mammals; File No. 16314

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ... National Oceanic and Atmospheric Administration Marine Mammals; File No. 16314 AGENCY: National Marine.... SUPPLEMENTARY INFORMATION: The subject permit is requested under the authority of the Marine Mammal Protection... importing of marine mammals (50 CFR part 216). The applicant requests a five-year permit to conduct...

  18. 75 FR 27300 - Marine Mammals; File No. 15126

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-14

    ... National Oceanic and Atmospheric Administration RIN 0648-XU87 Marine Mammals; File No. 15126 AGENCY.... ACTION: Notice; issuance of permit. SUMMARY: Notice is hereby given that NMFS National Marine Mammal... conduct research on marine mammals. ] ADDRESSES: The permit and related documents are available for...

  19. 75 FR 10463 - Marine Mammals; File No. 15126

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-08

    ... National Oceanic and Atmospheric Administration RIN 0648-XU87 Marine Mammals; File No. 15126 AGENCY.... ACTION: Notice; receipt of application. SUMMARY: Notice is hereby given that NMFS National Marine Mammal... conduct research on marine mammals in Alaska. DATES: Written, telefaxed, or e-mail comments must...

  20. 77 FR 12009 - Marine Mammals; File No. 16991

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ... National Oceanic and Atmospheric Administration RIN 0648-XB033 Marine Mammals; File No. 16991 AGENCY... under the authority of the Marine Mammal Protection Act of 1972, as amended (MMPA; 16 U.S.C. 1361 et seq.) and the regulations governing the taking and importing of marine mammals (50 CFR part 216)....

  1. 75 FR 15685 - Marine Mammals; Issuance of Permits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ... National Oceanic and Atmospheric Administration RIN 0648-XV53 Marine Mammals; Issuance of Permits AGENCY... Scientific Research on marine mammals. See SUPPLEMENTARY INFORMATION for a list of names and address of...) have been issued under the authority of the Marine Mammal Protection Act of 1972, as amended (16...

  2. 75 FR 1029 - Marine Mammals; File No. 14486

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-08

    ... National Oceanic and Atmospheric Administration RIN 0648-XT56 Marine Mammals; File No. 14486 AGENCY...), has applied in due form for a permit to receive, import, and export marine mammal specimens for... requested under the authority of the Marine Mammal Protection Act of 1972, as amended (MMPA; 16 U.S.C....

  3. 75 FR 54094 - Marine Mammals; File No. 486-1790

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... ecology, and behavior of pinnipeds in California. Marine mammals may be captured by a variety of... National Oceanic and Atmospheric Administration RIN 0648-XY74 Marine Mammals; File No. 486-1790 AGENCY...: The requested amendment has been granted under the authority of the Marine Mammal Protection Act...

  4. Pathophysiological analyses of cortical malformation using gyrencephalic mammals

    PubMed Central

    Masuda, Kosuke; Toda, Tomohisa; Shinmyo, Yohei; Ebisu, Haruka; Hoshiba, Yoshio; Wakimoto, Mayu; Ichikawa, Yoshie; Kawasaki, Hiroshi

    2015-01-01

    One of the most prominent features of the cerebral cortex of higher mammals is the presence of gyri. Because malformations of the cortical gyri are associated with severe disability in brain function, the mechanisms underlying malformations of the cortical gyri have been of great interest. Combining gyrencephalic carnivore ferrets and genetic manipulations using in utero electroporation, here we successfully recapitulated the cortical phenotypes of thanatophoric dysplasia (TD) by expressing fibroblast growth factor 8 in the ferret cerebral cortex. Strikingly, in contrast to TD mice, our TD ferret model showed not only megalencephaly but also polymicrogyria. We further uncovered that outer radial glial cells (oRGs) and intermediate progenitor cells (IPs) were markedly increased. Because it has been proposed that increased oRGs and/or IPs resulted in the appearance of cortical gyri during evolution, it seemed possible that increased oRGs and IPs underlie the pathogenesis of polymicrogyria. Our findings should help shed light on the molecular mechanisms underlying the formation and malformation of cortical gyri in higher mammals. PMID:26482531

  5. Pathophysiological analyses of cortical malformation using gyrencephalic mammals.

    PubMed

    Masuda, Kosuke; Toda, Tomohisa; Shinmyo, Yohei; Ebisu, Haruka; Hoshiba, Yoshio; Wakimoto, Mayu; Ichikawa, Yoshie; Kawasaki, Hiroshi

    2015-01-01

    One of the most prominent features of the cerebral cortex of higher mammals is the presence of gyri. Because malformations of the cortical gyri are associated with severe disability in brain function, the mechanisms underlying malformations of the cortical gyri have been of great interest. Combining gyrencephalic carnivore ferrets and genetic manipulations using in utero electroporation, here we successfully recapitulated the cortical phenotypes of thanatophoric dysplasia (TD) by expressing fibroblast growth factor 8 in the ferret cerebral cortex. Strikingly, in contrast to TD mice, our TD ferret model showed not only megalencephaly but also polymicrogyria. We further uncovered that outer radial glial cells (oRGs) and intermediate progenitor cells (IPs) were markedly increased. Because it has been proposed that increased oRGs and/or IPs resulted in the appearance of cortical gyri during evolution, it seemed possible that increased oRGs and IPs underlie the pathogenesis of polymicrogyria. Our findings should help shed light on the molecular mechanisms underlying the formation and malformation of cortical gyri in higher mammals. PMID:26482531

  6. Rensch's rule in large herbivorous mammals derived from metabolic scaling.

    PubMed

    Sibly, Richard M; Zuo, Wenyun; Kodric-Brown, Astrid; Brown, James H

    2012-02-01

    Rensch's rule, which states that the magnitude of sexual size dimorphism tends to increase with increasing body size, has evolved independently in three lineages of large herbivorous mammals: bovids (antelopes), cervids (deer), and macropodids (kangaroos). This pattern can be explained by a model that combines allometry, life-history theory, and energetics. The key features are that female group size increases with increasing body size and that males have evolved under sexual selection to grow large enough to control these groups of females. The model predicts relationships among body size and female group size, male and female age at first breeding, death and growth rates, and energy allocation of males to produce body mass and weapons. Model predictions are well supported by data for these megaherbivores. The model suggests hypotheses for why some other sexually dimorphic taxa, such as primates and pinnipeds (seals and sea lions), do or do not conform to Rensh's rule. PMID:22218307

  7. Selfish sentinels in cooperative mammals.

    PubMed

    Clutton-Brock, T H; O'Riain, M J; Brotherton, P N; Gaynor, D; Kansky, R; Griffin, A S; Manser, M

    1999-06-01

    Like humans engaged in risky activities, group members of some animal societies take turns acting as sentinels. Explanations of the evolution of sentinel behavior have frequently relied on kin selection or reciprocal altruism, but recent models suggest that guarding may be an individual's optimal activity once its stomach is full if no other animal is on guard. This paper provides support for this last explanation by showing that, in groups of meerkats (Suricata suricatta), animals guard from safe sites, and solitary individuals as well as group members spend part of their time on guard. Though individuals seldom take successive guarding bouts, there is no regular rota, and the provision of food increases contributions to guarding and reduces the latency between bouts by the same individual.

  8. Selfish sentinels in cooperative mammals.

    PubMed

    Clutton-Brock, T H; O'Riain, M J; Brotherton, P N; Gaynor, D; Kansky, R; Griffin, A S; Manser, M

    1999-06-01

    Like humans engaged in risky activities, group members of some animal societies take turns acting as sentinels. Explanations of the evolution of sentinel behavior have frequently relied on kin selection or reciprocal altruism, but recent models suggest that guarding may be an individual's optimal activity once its stomach is full if no other animal is on guard. This paper provides support for this last explanation by showing that, in groups of meerkats (Suricata suricatta), animals guard from safe sites, and solitary individuals as well as group members spend part of their time on guard. Though individuals seldom take successive guarding bouts, there is no regular rota, and the provision of food increases contributions to guarding and reduces the latency between bouts by the same individual. PMID:10356387

  9. Reconstructing the migration patterns of late Pleistocene mammals from northern Florida, USA

    NASA Astrophysics Data System (ADS)

    Hoppe, Kathryn A.; Koch, Paul L.

    2007-11-01

    We used analyses of the strontium isotope ( 87Sr/ 86Sr) ratios of tooth enamel to reconstruct the migration patterns of fossil mammals collected along the Aucilla River in northern Florida. Specimens date to the late-glacial period and before the last glacial maximum (pre-LGM). Deer and tapir displayed low 87Sr/ 86Sr ratios that were similar to the ratios of Florida environments, which suggest that these taxa did not migrate long distance outside of the Florida region. Mastodons, mammoths, and equids all displayed a wide range of 87Sr/ 86Sr ratios. Some individuals in each taxon displayed low 87Sr/ 86Sr ratios that suggest they ranged locally, while other animals had high 87Sr/ 86Sr ratios that suggest they migrated long distances (> 150 km) outside of the Florida region. Mastodons were the only taxa from this region that provided enough well-dated specimens to compare changes in migration patterns over time. Pre-LGM mastodons displayed significantly lower 87Sr/ 86Sr ratios than late-glacial mastodons, which suggests that late-glacial mastodons from Florida migrated longer distances than their earlier counterparts. This change in movement patterns reflects temporal changes in regional vegetation patterns.

  10. Utilizing new Mammal faunas for calibration of paleomagnetostratigraphy in the Kochkor basin, Kyrgyzstan.

    NASA Astrophysics Data System (ADS)

    McLaughlin, W. N. F.; Weldon, R. J.; Abdrakhmatov, K.; Hopkins, S. S. B.

    2015-12-01

    Kyrgyzstan is the most seismically active nation in the world, owning to the uplift of the Tien Shan mountain range. This record of faulting is far from simple though, with different dates of initiation spanning tens of millions of years in the published literature. Differentiating between these extremes is vital in terms of constructing earthquake hazard maps for the country. Much of the high degree of uncertainty comes from a lack of datable rocks within the time frame associated with the faulting. While paleomagnetic stratigraphic analyses provide highly accurate ages, they in turn need calibration points to preclude multiple possible matches to a global geochronological framework. Herein I provide the first description of Neogene fossil mammal faunas to act as biostratigraphic control for the paleomagnetic data. Dominating the faunal assemblage is rhinoceros species, Chilotherium anderssoni. This taxon is globally only known from 8.7-5.3 million years ago, constraining much of the stratigraphy to the latest Miocene to Pliocene. Additional taxa include Gazella, Samotherium, Hipparion, Hyaenaictithirium, Paleolagus, and Pliocervidae. As fossils are limited to the Miocene/Pliocene Chu Formation, we have also collected additional paleomagnetic samples from the lower Shamsi Formation to extend the age range covered and constraint the initiation of faulting.

  11. Late Cretaceous relatives of rabbits, rodents, and other extant eutherian mammals

    NASA Astrophysics Data System (ADS)

    Archibald, J. David; Averianov, Alexander O.; Ekdale, Eric G.

    2001-11-01

    Extant eutherian mammals and their most recent common ancestor constitute the crown group Placentalia. This taxon, plus all extinct taxa that share a more recent common ancestor with placentals than they do with Metatheria (including marsupials), constitute Eutheria. The oldest well documented eutherian-dominated fauna in the world is Dzharakuduk, Uzbekistan. Among eutherians that it yields is Kulbeckia, an 85-90-Myr-old member of Zalambdalestidae (a family of Late Cretaceous Asian eutherians). This extends Zalambdalestidae back by some 10 million years from sites in the Gobi Desert, Mongolia. A phylogenetic analysis of well described Late Cretaceous eutherians strongly supports Zalambdalestidae, less strongly supports `Zhelestidae' (a Late Cretaceous clade related to Tertiary ungulates), but does not support Asioryctitheria (a group of Late Cretaceous Asian eutherians). A second analysis incorporating placentals from clades that include rodents (Tribosphenomys), lagomorphs (Mimotona) and archaic ungulates (Protungulatum and Oxyprimus) strongly supports Zalambdalestidae in a clade with Glires (rabbits, rodents and extinct relatives) and less strongly `Zhelestidae' within a clade that includes archaic ungulates (`condylarths'). This argues that some Late Cretaceous eutherians belong within the crown group Placentalia. The ages of these taxa are in line with molecularly based estimates of 64-104Myr ago (median 84Myr ago) for the superordinal diversification of some placentals, but provide no support for a Late Cretaceous diversification of extant placental orders.

  12. C-values of seven marine mammal species determined by flow cytometry.

    PubMed

    Du, Bo; Wang, Ding

    2006-11-01

    C-values, which estimate genome size, have puzzled geneticists for years because they bear no relationship to organismal complexity. Though C-values have been estimated for thousands of species, considerably more data are required in order to better understanding genome evolution. This is particularly true for mammals, in which C-values are known for less than 8% of the total number of mammalian species. Among marine mammals, a C-value has been estimated only for the bottlenose dolphin (Tursiops truncatus). Thus examination of additional species of marine mammals is necessary for comparative purposes. It will enable a better understanding of marine mammal genome evolution, and it is also relevant to conservation, because larger genome size has been linked to increased likelihood of extinction in some plant and animal groups. Our study presents C-values of seven marine mammal species, including five cetacean species that are endangered to varying degrees. Similarly to the results for other groups, our results suggest that larger genome size in cetaceans is related to an increased likelihood of extinction. PMID:17189914

  13. Trends in North American small mammals found in common barn-owl (Tyto alba) dietary studies

    USGS Publications Warehouse

    Clark, D.R.; Bunck, C.M.

    1991-01-01

    Data on mammals were compiled from published studies of common barn-owl (Tyto alba) pellets. Mammalian composition of pellet samples was analyzed within geographic regions in regard to year, mean annual precipitation, latitude, and number of individual mammals in the sample. Percentages of individuals in pellets that were shrews increased whereas the percentages of rodents decreased with greater mean annual precipitation, especially in northern and western areas of North America. From the 1920s through 1980s, in northern and eastern areas the percentage of species that was shrews decreased, and in northern and central areas the percentage of individuals that was murid rats and mice increased. Human alterations of habitats during these seven decades are postulated to have caused changes in available small mammals, leading to changes in the barn-owl diet.

  14. Kisspeptin and Puberty in Mammals

    PubMed Central

    Terasawa, Ei; Guerriero, Kathryn A.; Plant, Tony M.

    2014-01-01

    Since the discovery of the G-protein coupled receptor (kisspeptin receptor) and its ligand, kisspeptin, our understanding of the neurobiological mechanisms that govern the pituitary-gonadal axis has evolved dramatically. In this chapter, we have reviewed progress regarding the relationship between kisspeptin and puberty, and have proposed a novel hypothesis for the role of kisspeptin signaling in the onset of this crucial developmental event. According to this hypothesis, although kisspeptin neurons in the arcuate nucleus (ARC) are critical for puberty, this is simply because these cells are an integral component of the hypothalamic GnRH pulse generating mechanism that drives intermittent release of the decapeptide, as an increase in GnRH is obligatory for the onset of puberty. In our model, ARC kisspeptin neurons play no “regulatory” role in controlling the timing of puberty. Rather, as a component of the neural network responsible for GnRH pulse generation, they subserve upstream regulatory mechanisms that are responsible for the timing of puberty. PMID:23550010

  15. Obesity Gene Atlas in Mammals

    PubMed Central

    Kunej, Tanja; Jevsinek Skok, Dasa; Zorc, Minja; Ogrinc, Ana; Michal, Jennifer J.; Kovac, Milena; Jiang, Zhihua

    2013-01-01

    Obesity in humans has increased at an alarming rate over the past two decades and has become one of the leading public health problems worldwide. Studies have revealed a large number of genes/markers that are associated with obesity and/or obesity-related phenotypes, indicating an urgent need to develop a central database for helping the community understand the genetic complexity of obesity. In the present study, we collected a total of 1,736 obesity associated loci and created a freely available obesity database, including 1,515 protein-coding genes and 221 microRNAs (miRNAs) collected from four mammalian species: human, cattle, rat, and mouse. These loci were integrated as orthologs on comparative genomic views in human, cattle, and mouse. The database and genomic views are freely available online at: http://www.integratomics-time.com/fat_deposition. Bioinformatics analyses of the collected data revealed some potential novel obesity related molecular markers which represent focal points for testing more targeted hypotheses and designing experiments for further studies. We believe that this centralized database on obesity and adipogenesis will facilitate development of comparative systems biology approaches to address this important health issue in human and their potential applications in animals. PMID:25031655

  16. Synchronous extinction of North America's Pleistocene mammals.

    PubMed

    Faith, J Tyler; Surovell, Todd A

    2009-12-01

    The late Pleistocene witnessed the extinction of 35 genera of North American mammals. The last appearance dates of 16 of these genera securely fall between 12,000 and 10,000 radiocarbon years ago (approximately 13,800-11,400 calendar years B.P.), although whether the absence of fossil occurrences for the remaining 19 genera from this time interval is the result of sampling error or temporally staggered extinctions is unclear. Analysis of the chronology of extinctions suggests that sampling error can explain the absence of terminal Pleistocene last appearance dates for the remaining 19 genera. The extinction chronology of North American Pleistocene mammals therefore can be characterized as a synchronous event that took place 12,000-10,000 radiocarbon years B.P. Results favor an extinction mechanism that is capable of wiping out up to 35 genera across a continent in a geologic instant.

  17. Prioritizing conservation investments for mammal species globally

    PubMed Central

    Wilson, Kerrie A.; Evans, Megan C.; Di Marco, Moreno; Green, David C.; Boitani, Luigi; Possingham, Hugh P.; Chiozza, Federica; Rondinini, Carlo

    2011-01-01

    We need to set priorities for conservation because we cannot do everything, everywhere, at the same time. We determined priority areas for investment in threat abatement actions, in both a cost-effective and spatially and temporally explicit way, for the threatened mammals of the world. Our analysis presents the first fine-resolution prioritization analysis for mammals at a global scale that accounts for the risk of habitat loss, the actions required to abate this risk, the costs of these actions and the likelihood of investment success. We evaluated the likelihood of success of investments using information on the past frequency and duration of legislative effectiveness at a country scale. The establishment of new protected areas was the action receiving the greatest investment, while restoration was never chosen. The resolution of the analysis and the incorporation of likelihood of success made little difference to this result, but affected the spatial location of these investments. PMID:21844046

  18. Bartonella spp. in Small Mammals, Benin.

    PubMed

    Martin-Alonso, Aarón; Houemenou, Gualbert; Abreu-Yanes, Estefanía; Valladares, Basilio; Feliu, Carlos; Foronda, Pilar

    2016-04-01

    This study aimed to investigate the prevalence and genetic diversity of Bartonella organisms in small mammals in Cotonou, Benin. We captured 163 rodents and 12 insectivores and successfully detected Bartonella DNA from 13 of the 175 small mammal individuals. Bartonella spp., identical or closely related to Bartonella elizabethae, Bartonella tribocorum, and Bartonella rochalimae, was detected. A potential new Bartonella species, proposed as Candidatus Bartonella mastomydis, was found in three Mastomys individuals and genetically characterized by targeting two housekeeping genes (rpoB and gltA) and the intergenic species region. However, 20.8% of gray rats were found to be infected with Bartonella spp., and none of the black rats analyzed was positive. This work may be important from a public health point of view due to the zoonotic nature of the Bartonella species detected and warrants further investigation on the unknown zoonotic potential of this newly proposed Bartonella species. PMID:26910412

  19. Evolution of climate niches in European mammals?

    PubMed Central

    Dormann, Carsten F.; Gruber, Bernd; Winter, Marten; Herrmann, Dirk

    2010-01-01

    Our ability to predict consequences of climate change is severely impaired by the lack of knowledge on the ability of species to adapt to changing environmental conditions. We used distribution data for 140 mammal species in Europe, together with data on climate, land cover and topography, to derive a statistical description of their realized climate niche. We then compared climate niche overlap of pairs of species, selected on the basis of phylogenetic information. In contrast to expectations, related species were not similar in their climate niche. Rather, even species pairs that had a common ancestor less than 1 Ma already display very high climate niche distances. We interpret our finding as a strong interspecific competitive constraint on the realized niche, rather than a rapid evolution of the fundamental niche. If correct, our results imply a very limited usefulness of climate niche models for the prediction of future mammal distributions. PMID:19828492

  20. Evolution of climate niches in European mammals?

    PubMed

    Dormann, Carsten F; Gruber, Bernd; Winter, Marten; Herrmann, Dirk

    2010-04-23

    Our ability to predict consequences of climate change is severely impaired by the lack of knowledge on the ability of species to adapt to changing environmental conditions. We used distribution data for 140 mammal species in Europe, together with data on climate, land cover and topography, to derive a statistical description of their realized climate niche. We then compared climate niche overlap of pairs of species, selected on the basis of phylogenetic information. In contrast to expectations, related species were not similar in their climate niche. Rather, even species pairs that had a common ancestor less than 1 Ma already display very high climate niche distances. We interpret our finding as a strong interspecific competitive constraint on the realized niche, rather than a rapid evolution of the fundamental niche. If correct, our results imply a very limited usefulness of climate niche models for the prediction of future mammal distributions.

  1. Bartonella spp. in Small Mammals, Benin.

    PubMed

    Martin-Alonso, Aarón; Houemenou, Gualbert; Abreu-Yanes, Estefanía; Valladares, Basilio; Feliu, Carlos; Foronda, Pilar

    2016-04-01

    This study aimed to investigate the prevalence and genetic diversity of Bartonella organisms in small mammals in Cotonou, Benin. We captured 163 rodents and 12 insectivores and successfully detected Bartonella DNA from 13 of the 175 small mammal individuals. Bartonella spp., identical or closely related to Bartonella elizabethae, Bartonella tribocorum, and Bartonella rochalimae, was detected. A potential new Bartonella species, proposed as Candidatus Bartonella mastomydis, was found in three Mastomys individuals and genetically characterized by targeting two housekeeping genes (rpoB and gltA) and the intergenic species region. However, 20.8% of gray rats were found to be infected with Bartonella spp., and none of the black rats analyzed was positive. This work may be important from a public health point of view due to the zoonotic nature of the Bartonella species detected and warrants further investigation on the unknown zoonotic potential of this newly proposed Bartonella species.

  2. An Analysis of Marine Mammal Self-Reports and Observer Reports from 1996-2014

    NASA Astrophysics Data System (ADS)

    McFarland, M. H.

    2015-12-01

    Over the past two decades commercial fishing vessel owners have been reporting their interactions with marine mammals in accordance with Section 118 of the Marine Mammal Protection Act. The objective of this study is to analyze marine mammal fisheries interactions data from fishermen self-reports and observer reports. We analyzed self-reports from 1996 - 2014 and Pacific Islands observer data from 2001 - 2014, and Northeast observer data from 1996 - 2014. We identify trends in the national marine mammal mortality/injury (M/I) self-report dataset; identify presence of complementary reports between self-reports and observer reports; and determine the compliance rate of self-reports and observer reports. The results of the self-report analysis indicate that the Greater Atlantic Region (GAR) receives the most M/I reports of the five National Marine Fisheries Service (NMFS) regional offices. The rate of animals reported as killed is three times higher than the rate for animals injured. Dolphins and porpoises are the most frequently reported species and gillnets are the most frequently reported gear type. This study will provide fisheries managers a greater understanding of the effectiveness of the requirement for fishermen to report moralities and injuries of marine mammals incidentally taken during commercial fishing operations. Refinements to the Marine Mammal Authorization Program (MMAP) reporting form will provide more accurate estimates of the M/I rate of marine mammals in each region and will help address the challenges with collecting self-reported incidental take data. Furthermore, the results can be used by managers to determine if self-reporting is informative and should be continued, with form improvements made to increase accuracy, or if the corresponding observer reports serve as sufficient data by themselves.

  3. Classification of avian haemolytic Actinobacillus-like organisms (Bisgaard taxon 26) associated with anseriforme birds as Actinobacillus anseriformium sp. nov.

    PubMed

    Bisgaard, M; Christensen, H

    2012-02-01

    Avian haemolytic Actinobacillus-like organisms have tentatively been named Bisgaard taxon 26. Phenotypic information has been published on 65 strains of this taxon. In the current study, 31 isolates were selected for genotypic characterization. Thirty strains had the same rpoB sequence and only one strain diverged in 1 nt. The highest rpoB similarity to members of other taxa was 89.7 % to the type strain of Actinobacillus equuli subsp. haemolyticus and the similarity to the type strain of the type species, Actinobacillus lignieresii, was 88.2 %. The lowest 16S rRNA gene sequence similarity between strains of the group was determined in previous investigations to be 99.6 % and the highest similarities of 96.4 and 96.2 % outside the group were obtained to the reference strain of Actinobacillus genomospecies 2 and to the type strain of A. equuli subsp. equuli, respectively; 95.8-95.3 % similarity was obtained with the type strain of A. lignieresii. recN gene sequence similarities within the group were from 99.5 % (strains F66(T) and F64) to 99.8 % (strains F66(T) and F67) corresponding to genome similarities of 93.9-94.6 %, which are near the upper limit for species compared with other members of the Pasteurellaceae. The highest recN similarity outside the group (83.4 %) was observed to the type strain of Actinobacillus capsulatus, whereas the similarity to the type strain of A. lignieresii was 80.9 %, corresponding to genome similarities of 57.7 and 52.0 %, respectively. All isolates meet the phenotypic characters outlined for Actinobacillus (urease-, phosphatase- and porphyrin-positive, indole-negative, acid production from fructose, sucrose, maltose and dextrin). β-Haemolysis of bovine blood is observed and isolates may demonstrate in vitro satellitic growth, referred to as V-factor or NAD requirement. Isolates have been obtained from the upper respiratory tract of web-footed birds in which they may cause sinusitis, conjunctivitis and

  4. Collaborating to conserve large mammals in Southeast Asia.

    PubMed

    Steinmetz, Robert; Chutipong, Wanlop; Seuaturien, Naret

    2006-10-01

    Depressed mammal densities characterize the interior of many Southeast Asian protected areas, and are the result of commercial and subsistence hunting. Local people are part of this problem but can participate in solutions through improved partnerships that incorporate local knowledge into problem diagnosis. The process of involving local people helps build a constituency that is more aware of its role (positive and negative) in a protected area and generates site-specific conservation assessments for management planning. We illustrate the practical details of initiating such a partnership through our work in a Thai wildlife sanctuary. Many protected areas in Southeast Asia present similar opportunities. In local workshops, village woodsmen were led through ranking exercises to develop a spatially explicit picture of 20-year trends in the abundance of 31 mammal species and to compare species-specific causes for declines. Within five taxonomic groups, leaf monkeys (primates), porcupines (rodents), tigers (large carnivores), civets (small carnivores), and elephants (ungulates) had declined most severely (37-74%). Commercial hunting contributed heavily to extensive population declines for most species, and subsistence hunting was locally significant for some small carnivores, leaf monkeys, and deer. Workshops thus clarified which species were at highest risk of local extinction, where the most threatened populations were, and causes for these patterns. Most important, they advanced a shared problem definition, thereby unlocking opportunities for collaboration. As a result, local people and sanctuary managers have increased communication, initiated joint monitoring and patrolling, and established wildlife recovery zones. Using local knowledge has limitations, but the process of engaging local people promotes collaborative action that large mammals in Southeast Asia need.

  5. Functional constraints on tooth morphology in carnivorous mammals

    PubMed Central

    2012-01-01

    Background The range of potential morphologies resulting from evolution is limited by complex interacting processes, ranging from development to function. Quantifying these interactions is important for understanding adaptation and convergent evolution. Using three-dimensional reconstructions of carnivoran and dasyuromorph tooth rows, we compared statistical models of the relationship between tooth row shape and the opposing tooth row, a static feature, as well as measures of mandibular motion during chewing (occlusion), which are kinetic features. This is a new approach to quantifying functional integration because we use measures of movement and displacement, such as the amount the mandible translates laterally during occlusion, as opposed to conventional morphological measures, such as mandible length and geometric landmarks. By sampling two distantly related groups of ecologically similar mammals, we study carnivorous mammals in general rather than a specific group of mammals. Results Statistical model comparisons demonstrate that the best performing models always include some measure of mandibular motion, indicating that functional and statistical models of tooth shape as purely a function of the opposing tooth row are too simple and that increased model complexity provides a better understanding of tooth form. The predictors of the best performing models always included the opposing tooth row shape and a relative linear measure of mandibular motion. Conclusions Our results provide quantitative support of long-standing hypotheses of tooth row shape as being influenced by mandibular motion in addition to the opposing tooth row. Additionally, this study illustrates the utility and necessity of including kinetic features in analyses of morphological integration. PMID:22899809

  6. Collaborating to conserve large mammals in Southeast Asia.

    PubMed

    Steinmetz, Robert; Chutipong, Wanlop; Seuaturien, Naret

    2006-10-01

    Depressed mammal densities characterize the interior of many Southeast Asian protected areas, and are the result of commercial and subsistence hunting. Local people are part of this problem but can participate in solutions through improved partnerships that incorporate local knowledge into problem diagnosis. The process of involving local people helps build a constituency that is more aware of its role (positive and negative) in a protected area and generates site-specific conservation assessments for management planning. We illustrate the practical details of initiating such a partnership through our work in a Thai wildlife sanctuary. Many protected areas in Southeast Asia present similar opportunities. In local workshops, village woodsmen were led through ranking exercises to develop a spatially explicit picture of 20-year trends in the abundance of 31 mammal species and to compare species-specific causes for declines. Within five taxonomic groups, leaf monkeys (primates), porcupines (rodents), tigers (large carnivores), civets (small carnivores), and elephants (ungulates) had declined most severely (37-74%). Commercial hunting contributed heavily to extensive population declines for most species, and subsistence hunting was locally significant for some small carnivores, leaf monkeys, and deer. Workshops thus clarified which species were at highest risk of local extinction, where the most threatened populations were, and causes for these patterns. Most important, they advanced a shared problem definition, thereby unlocking opportunities for collaboration. As a result, local people and sanctuary managers have increased communication, initiated joint monitoring and patrolling, and established wildlife recovery zones. Using local knowledge has limitations, but the process of engaging local people promotes collaborative action that large mammals in Southeast Asia need. PMID:17002757

  7. Paternal care and litter size coevolution in mammals

    PubMed Central

    Hobson, Liane

    2016-01-01

    Biparental care of offspring occurs in diverse mammalian genera and is particularly common among species with socially monogamous mating systems. Despite numerous well-documented examples, however, the evolutionary causes and consequences of paternal care in mammals are not well understood. Here, we investigate the evolution of paternal care in relation to offspring production. Using comparative analyses to test for evidence of evolutionary associations between male care and life-history traits, we explore if biparental care is likely to have evolved because of the importance of male care to offspring survival, or if evolutionary increases in offspring production are likely to result from the evolution of biparental care. Overall, we find no evidence that paternal care has evolved in response to benefits of supporting females to rear particularly costly large offspring or litters. Rather, our findings suggest that increases in offspring production are more likely to follow the evolution of paternal care, specifically where males contribute depreciable investment such as provisioning young. Through coevolution with litter size, we conclude that paternal care in mammals is likely to play an important role in stabilizing monogamous mating systems and could ultimately promote the evolution of complex social behaviours. PMID:27097924

  8. The Grinnell Project; Small Mammal Responses to Climate in California

    NASA Astrophysics Data System (ADS)

    Conroy, C. C.; Koo, M.; Monahan, B.; Parra, J.; Moritz, C.

    2006-12-01

    Between 1915 and 1920, Joseph Grinnell and colleagues investigated the diversity of mammals, reptiles, amphibians and birds across what they termed the Yosemite Transect, an area spanning portions of the San Joaquin Valley, the Sierra Nevada, including about 1/3 of Yosemite National Park, and ending at Mono Lake. Their data collection included preservation of series of specimens at a large number of locations, point counts of birds, photography and extensive natural history notes, all of which are still archived at the Museum of Vertebrate Zoology at UC Berkeley. Beginning in 2003, researchers from the MVZ began retracing this work, collecting specimens, using point counts, and retaking some photographs. The comparison of the two periods indicates that some mammals have shifted their ranges greatly. Most taxa show an elevation increase, either an increase at the top for middle elevation species, or a retraction at the bottom for higher elevation species. However, not all species moved, and one high elevation species moved down. To further investigate how changes observed in Yosemite might also apply to larger spatial scales, our group has been using historic climate surfaces, historic specimen localities, and a variety of modeling methods to predict statewide changes in species' distributions. Other potential sites to be revisited include the Lassen Transect in Northern California, the Colorado River, and the San Bernardino Mountains.

  9. Sperm competition drives the evolution of suicidal reproduction in mammals

    PubMed Central

    Fisher, Diana O.; Dickman, Christopher R.; Jones, Menna E.; Blomberg, Simon P.

    2013-01-01

    Suicidal reproduction (semelparity) has evolved in only four genera of mammals. In these insectivorous marsupials, all males die after mating, when failure of the corticosteroid feedback mechanism elevates stress hormone levels during the mating season and causes lethal immune system collapse (die-off). We quantitatively test and resolve the evolutionary causes of this surprising and extreme life history strategy. We show that as marsupial predators in Australia, South America, and Papua New Guinea diversified into higher latitudes, seasonal predictability in abundance of their arthropod prey increased in multiple habitats. More-predictable prey peaks were associated with shorter annual breeding seasons, consistent with the suggestion that females accrue fitness benefits by timing peak energy demands of reproduction to coincide with maximum food abundance. We demonstrate that short mating seasons intensified reproductive competition between males, increasing male energy investment in copulations and reducing male postmating survival. However, predictability of annual prey cycles alone does not explain suicidal reproduction, because unlike insect abundance, peak ovulation dates in semelparous species are often synchronized to the day among years, triggered by a species-specific rate of change of photoperiod. Among species with low postmating male survival, we show that those with suicidal reproduction have shorter mating seasons and larger testes relative to body size. This indicates that lethal effort is adaptive in males because females escalate sperm competition by further shortening and synchronizing the annual mating period and mating promiscuously. We conclude that precopulatory sexual selection by females favored the evolution of suicidal reproduction in mammals. PMID:24101455

  10. Sperm competition drives the evolution of suicidal reproduction in mammals.

    PubMed

    Fisher, Diana O; Dickman, Christopher R; Jones, Menna E; Blomberg, Simon P

    2013-10-29

    Suicidal reproduction (semelparity) has evolved in only four genera of mammals. In these insectivorous marsupials, all males die after mating, when failure of the corticosteroid feedback mechanism elevates stress hormone levels during the mating season and causes lethal immune system collapse (die-off). We quantitatively test and resolve the evolutionary causes of this surprising and extreme life history strategy. We show that as marsupial predators in Australia, South America, and Papua New Guinea diversified into higher latitudes, seasonal predictability in abundance of their arthropod prey increased in multiple habitats. More-predictable prey peaks were associated with shorter annual breeding seasons, consistent with the suggestion that females accrue fitness benefits by timing peak energy demands of reproduction to coincide with maximum food abundance. We demonstrate that short mating seasons intensified reproductive competition between males, increasing male energy investment in copulations and reducing male postmating survival. However, predictability of annual prey cycles alone does not explain suicidal reproduction, because unlike insect abundance, peak ovulation dates in semelparous species are often synchronized to the day among years, triggered by a species-specific rate of change of photoperiod. Among species with low postmating male survival, we show that those with suicidal reproduction have shorter mating seasons and larger testes relative to body size. This indicates that lethal effort is adaptive in males because females escalate sperm competition by further shortening and synchronizing the annual mating period and mating promiscuously. We conclude that precopulatory sexual selection by females favored the evolution of suicidal reproduction in mammals.

  11. Paternal care and litter size coevolution in mammals.

    PubMed

    Stockley, Paula; Hobson, Liane

    2016-04-27

    Biparental care of offspring occurs in diverse mammalian genera and is particularly common among species with socially monogamous mating systems. Despite numerous well-documented examples, however, the evolutionary causes and consequences of paternal care in mammals are not well understood. Here, we investigate the evolution of paternal care in relation to offspring production. Using comparative analyses to test for evidence of evolutionary associations between male care and life-history traits, we explore if biparental care is likely to have evolved because of the importance of male care to offspring survival, or if evolutionary increases in offspring production are likely to result from the evolution of biparental care. Overall, we find no evidence that paternal care has evolved in response to benefits of supporting females to rear particularly costly large offspring or litters. Rather, our findings suggest that increases in offspring production are more likely to follow the evolution of paternal care, specifically where males contribute depreciable investment such as provisioning young. Through coevolution with litter size, we conclude that paternal care in mammals is likely to play an important role in stabilizing monogamous mating systems and could ultimately promote the evolution of complex social behaviours. PMID:27097924

  12. Future hotspots of terrestrial mammal loss.

    PubMed

    Visconti, Piero; Pressey, Robert L; Giorgini, Daniele; Maiorano, Luigi; Bakkenes, Michel; Boitani, Luigi; Alkemade, Rob; Falcucci, Alessandra; Chiozza, Federica; Rondinini, Carlo

    2011-09-27

    Current levels of endangerment and historical trends of species and habitats are the main criteria used to direct conservation efforts globally. Estimates of future declines, which might indicate different priorities than past declines, have been limited by the lack of appropriate data and models. Given that much of conservation is about anticipating and responding to future threats, our inability to look forward at a global scale has been a major constraint on effective action. Here, we assess the geography and extent of projected future changes in suitable habitat for terrestrial mammals within their present ranges. We used a global earth-system model, IMAGE, coupled with fine-scale habitat suitability models and parametrized according to four global scenarios of human development. We identified the most affected countries by 2050 for each scenario, assuming that no additional conservation actions other than those described in the scenarios take place. We found that, with some exceptions, most of the countries with the largest predicted losses of suitable habitat for mammals are in Africa and the Americas. African and North American countries were also predicted to host the most species with large proportional global declines. Most of the countries we identified as future hotspots of terrestrial mammal loss have little or no overlap with the present global conservation priorities, thus confirming the need for forward-looking analyses in conservation priority setting. The expected growth in human populations and consumption in hotspots of future mammal loss mean that local conservation actions such as protected areas might not be sufficient to mitigate losses. Other policies, directed towards the root causes of biodiversity loss, are required, both in Africa and other parts of the world.

  13. Future hotspots of terrestrial mammal loss

    PubMed Central

    Visconti, Piero; Pressey, Robert L.; Giorgini, Daniele; Maiorano, Luigi; Bakkenes, Michel; Boitani, Luigi; Alkemade, Rob; Falcucci, Alessandra; Chiozza, Federica; Rondinini, Carlo

    2011-01-01

    Current levels of endangerment and historical trends of species and habitats are the main criteria used to direct conservation efforts globally. Estimates of future declines, which might indicate different priorities than past declines, have been limited by the lack of appropriate data and models. Given that much of conservation is about anticipating and responding to future threats, our inability to look forward at a global scale has been a major constraint on effective action. Here, we assess the geography and extent of projected future changes in suitable habitat for terrestrial mammals within their present ranges. We used a global earth-system model, IMAGE, coupled with fine-scale habitat suitability models and parametrized according to four global scenarios of human development. We identified the most affected countries by 2050 for each scenario, assuming that no additional conservation actions other than those described in the scenarios take place. We found that, with some exceptions, most of the countries with the largest predicted losses of suitable habitat for mammals are in Africa and the Americas. African and North American countries were also predicted to host the most species with large proportional global declines. Most of the countries we identified as future hotspots of terrestrial mammal loss have little or no overlap with the present global conservation priorities, thus confirming the need for forward-looking analyses in conservation priority setting. The expected growth in human populations and consumption in hotspots of future mammal loss mean that local conservation actions such as protected areas might not be sufficient to mitigate losses. Other policies, directed towards the root causes of biodiversity loss, are required, both in Africa and other parts of the world. PMID:21844048

  14. Future hotspots of terrestrial mammal loss.

    PubMed

    Visconti, Piero; Pressey, Robert L; Giorgini, Daniele; Maiorano, Luigi; Bakkenes, Michel; Boitani, Luigi; Alkemade, Rob; Falcucci, Alessandra; Chiozza, Federica; Rondinini, Carlo

    2011-09-27

    Current levels of endangerment and historical trends of species and habitats are the main criteria used to direct conservation efforts globally. Estimates of future declines, which might indicate different priorities than past declines, have been limited by the lack of appropriate data and models. Given that much of conservation is about anticipating and responding to future threats, our inability to look forward at a global scale has been a major constraint on effective action. Here, we assess the geography and extent of projected future changes in suitable habitat for terrestrial mammals within their present ranges. We used a global earth-system model, IMAGE, coupled with fine-scale habitat suitability models and parametrized according to four global scenarios of human development. We identified the most affected countries by 2050 for each scenario, assuming that no additional conservation actions other than those described in the scenarios take place. We found that, with some exceptions, most of the countries with the largest predicted losses of suitable habitat for mammals are in Africa and the Americas. African and North American countries were also predicted to host the most species with large proportional global declines. Most of the countries we identified as future hotspots of terrestrial mammal loss have little or no overlap with the present global conservation priorities, thus confirming the need for forward-looking analyses in conservation priority setting. The expected growth in human populations and consumption in hotspots of future mammal loss mean that local conservation actions such as protected areas might not be sufficient to mitigate losses. Other policies, directed towards the root causes of biodiversity loss, are required, both in Africa and other parts of the world. PMID:21844048

  15. Elk herbivory alters small mammal assemblages in high-elevation drainages.

    PubMed

    Parsons, Elliott W R; Maron, John L; Martin, Thomas E

    2013-03-01

    Heavy herbivory by ungulates can substantially alter habitat, but the indirect consequences of habitat modification for animal assemblages that rely on that habitat are not well studied. This is a particularly important topic given that climate change can alter plant-herbivore interactions. We explored short-term responses of small mammal communities to recent exclusion of Rocky Mountain elk (Cervus elaphus) in high-elevation riparian drainages in northern Arizona, where elk impacts on vegetation have increased over the past quarter century associated with climate change. We used 10-ha elk exclosures paired with unfenced control drainages to examine how browsing influenced the habitat use, relative abundance, richness and diversity of a small mammal assemblage. We found that the small mammal assemblage changed significantly after 5 years of elk exclusion. Relative abundance of voles (Microtus mexicanus) increased in exclosure drainages, likely due to an increase in habitat quality. The relative abundances of woodrats (Neotoma neomexicana) and two species of mice (Peromyscus maniculatus and P. boylii) decreased in the controls, while remaining stable in exclosures. The decline of mice in control drainages was likely due to the decline in shrub cover that they use. Thus, elk exclusion may have maintained or improved habitat for mice inside the exclosures while habitat quality and mouse abundance both declined outside the fences. Finally, small mammal species richness increased in the exclosures relative to the controls while species diversity showed no significant trends. Together, our results show that relaxation of heavy herbivore pressure by a widespread native ungulate can lead to rapid changes in small mammal assemblages. Moreover, exclusion of large herbivores can yield rapid responses by vegetation that may enhance or maintain habitat quality for small mammal populations. PMID:23163813

  16. Elk herbivory alters small mammal assemblages in high-elevation drainages.

    PubMed

    Parsons, Elliott W R; Maron, John L; Martin, Thomas E

    2013-03-01

    Heavy herbivory by ungulates can substantially alter habitat, but the indirect consequences of habitat modification for animal assemblages that rely on that habitat are not well studied. This is a particularly important topic given that climate change can alter plant-herbivore interactions. We explored short-term responses of small mammal communities to recent exclusion of Rocky Mountain elk (Cervus elaphus) in high-elevation riparian drainages in northern Arizona, where elk impacts on vegetation have increased over the past quarter century associated with climate change. We used 10-ha elk exclosures paired with unfenced control drainages to examine how browsing influenced the habitat use, relative abundance, richness and diversity of a small mammal assemblage. We found that the small mammal assemblage changed significantly after 5 years of elk exclusion. Relative abundance of voles (Microtus mexicanus) increased in exclosure drainages, likely due to an increase in habitat quality. The relative abundances of woodrats (Neotoma neomexicana) and two species of mice (Peromyscus maniculatus and P. boylii) decreased in the controls, while remaining stable in exclosures. The decline of mice in control drainages was likely due to the decline in shrub cover that they use. Thus, elk exclusion may have maintained or improved habitat for mice inside the exclosures while habitat quality and mouse abundance both declined outside the fences. Finally, small mammal species richness increased in the exclosures relative to the controls while species diversity showed no significant trends. Together, our results show that relaxation of heavy herbivore pressure by a widespread native ungulate can lead to rapid changes in small mammal assemblages. Moreover, exclusion of large herbivores can yield rapid responses by vegetation that may enhance or maintain habitat quality for small mammal populations.

  17. Global distribution and conservation of marine mammals.

    PubMed

    Pompa, Sandra; Ehrlich, Paul R; Ceballos, Gerardo

    2011-08-16

    We identified 20 global key conservation sites for all marine (123) and freshwater (6) mammal species based on their geographic ranges. We created geographic range maps for all 129 species and a Geographic Information System database for a 46,184 1° x 1° grid-cells, ∼10,000-km(2). Patterns of species richness, endemism, and risk were variable among all species and species groups. Interestingly, marine mammal species richness was correlated strongly with areas of human impact across the oceans. Key conservation sites in the global geographic grid were determined either by their species richness or by their irreplaceability or uniqueness, because of the presence of endemic species. Nine key conservation sites, comprising the 2.5% of the grid cells with the highest species richness, were found, mostly in temperate latitudes, and hold 84% of marine mammal species. In addition, we identified 11 irreplaceable key conservation sites, six of which were found in freshwater bodies and five in marine regions. These key conservation sites represent critical areas of conservation value at a global level and can serve as a first step for adopting global strategies with explicit geographic conservation targets for Marine Protected Areas.

  18. A comparative analysis of marine mammal tracheas.

    PubMed

    Moore, Colby; Moore, Michael; Trumble, Stephen; Niemeyer, Misty; Lentell, Betty; McLellan, William; Costidis, Alexander; Fahlman, Andreas

    2014-04-01

    In 1940, Scholander suggested that stiffened upper airways remained open and received air from highly compressible alveoli during marine mammal diving. There are few data available on the structural and functional adaptations of the marine mammal respiratory system. The aim of this research was to investigate the anatomical (gross) and structural (compliance) characteristics of excised marine mammal tracheas. Here, we defined different types of tracheal structures, categorizing pinniped tracheas by varying degrees of continuity of cartilage (categories 1-4) and cetacean tracheas by varying compliance values (categories 5A and 5B). Some tracheas fell into more than one category along their length; for example, the harbor seal (Phoca vitulina) demonstrated complete rings cranially, and as the trachea progressed caudally, tracheal rings changed morphology. Dolphins and porpoises had less stiff, more compliant spiraling rings while beaked whales had very stiff, less compliant spiraling rings. The pressure-volume (P-V) relationships of isolated tracheas from different species were measured to assess structural differences between species. These findings lend evidence for pressure-induced collapse and re-inflation of lungs, perhaps influencing variability in dive depth or ventilation rates of the species investigated.

  19. The RIKEN integrated database of mammals

    PubMed Central

    Masuya, Hiroshi; Makita, Yuko; Kobayashi, Norio; Nishikata, Koro; Yoshida, Yuko; Mochizuki, Yoshiki; Doi, Koji; Takatsuki, Terue; Waki, Kazunori; Tanaka, Nobuhiko; Ishii, Manabu; Matsushima, Akihiro; Takahashi, Satoshi; Hijikata, Atsushi; Kozaki, Kouji; Furuichi, Teiichi; Kawaji, Hideya; Wakana, Shigeharu; Nakamura, Yukio; Yoshiki, Atsushi; Murata, Takehide; Fukami-Kobayashi, Kaoru; Mohan, Sujatha; Ohara, Osamu; Hayashizaki, Yoshihide; Mizoguchi, Riichiro; Obata, Yuichi; Toyoda, Tetsuro

    2011-01-01

    The RIKEN integrated database of mammals (http://scinets.org/db/mammal) is the official undertaking to integrate its mammalian databases produced from multiple large-scale programs that have been promoted by the institute. The database integrates not only RIKEN’s original databases, such as FANTOM, the ENU mutagenesis program, the RIKEN Cerebellar Development Transcriptome Database and the Bioresource Database, but also imported data from public databases, such as Ensembl, MGI and biomedical ontologies. Our integrated database has been implemented on the infrastructure of publication medium for databases, termed SciNetS/SciNeS, or the Scientists’ Networking System, where the data and metadata are structured as a semantic web and are downloadable in various standardized formats. The top-level ontology-based implementation of mammal-related data directly integrates the representative knowledge and individual data records in existing databases to ensure advanced cross-database searches and reduced unevenness of the data management operations. Through the development of this database, we propose a novel methodology for the development of standardized comprehensive management of heterogeneous data sets in multiple databases to improve the sustainability, accessibility, utility and publicity of the data of biomedical information. PMID:21076152

  20. Global distribution and conservation of marine mammals

    PubMed Central

    Pompa, Sandra; Ehrlich, Paul R.; Ceballos, Gerardo

    2011-01-01

    We identified 20 global key conservation sites for all marine (123) and freshwater (6) mammal species based on their geographic ranges. We created geographic range maps for all 129 species and a Geographic Information System database for a 46,184 1° x 1° grid-cells, ∼10,000-km2. Patterns of species richness, endemism, and risk were variable among all species and species groups. Interestingly, marine mammal species richness was correlated strongly with areas of human impact across the oceans. Key conservation sites in the global geographic grid were determined either by their species richness or by their irreplaceability or uniqueness, because of the presence of endemic species. Nine key conservation sites, comprising the 2.5% of the grid cells with the highest species richness, were found, mostly in temperate latitudes, and hold 84% of marine mammal species. In addition, we identified 11 irreplaceable key conservation sites, six of which were found in freshwater bodies and five in marine regions. These key conservation sites represent critical areas of conservation value at a global level and can serve as a first step for adopting global strategies with explicit geographic conservation targets for Marine Protected Areas. PMID:21808012

  1. Phylogenetic conservatism of environmental niches in mammals.

    PubMed

    Cooper, Natalie; Freckleton, Rob P; Jetz, Walter

    2011-08-01

    Phylogenetic niche conservatism is the pattern where close relatives occupy similar niches, whereas distant relatives are more dissimilar. We suggest that niche conservatism will vary across clades in relation to their characteristics. Specifically, we investigate how conservatism of environmental niches varies among mammals according to their latitude, range size, body size and specialization. We use the Brownian rate parameter, σ(2), to measure the rate of evolution in key variables related to the ecological niche and define the more conserved group as the one with the slower rate of evolution. We find that tropical, small-ranged and specialized mammals have more conserved thermal niches than temperate, large-ranged or generalized mammals. Partitioning niche conservatism into its spatial and phylogenetic components, we find that spatial effects on niche variables are generally greater than phylogenetic effects. This suggests that recent evolution and dispersal have more influence on species' niches than more distant evolutionary events. These results have implications for our understanding of the role of niche conservatism in species richness patterns and for gauging the potential for species to adapt to global change.

  2. The RIKEN integrated database of mammals.

    PubMed

    Masuya, Hiroshi; Makita, Yuko; Kobayashi, Norio; Nishikata, Koro; Yoshida, Yuko; Mochizuki, Yoshiki; Doi, Koji; Takatsuki, Terue; Waki, Kazunori; Tanaka, Nobuhiko; Ishii, Manabu; Matsushima, Akihiro; Takahashi, Satoshi; Hijikata, Atsushi; Kozaki, Kouji; Furuichi, Teiichi; Kawaji, Hideya; Wakana, Shigeharu; Nakamura, Yukio; Yoshiki, Atsushi; Murata, Takehide; Fukami-Kobayashi, Kaoru; Mohan, Sujatha; Ohara, Osamu; Hayashizaki, Yoshihide; Mizoguchi, Riichiro; Obata, Yuichi; Toyoda, Tetsuro

    2011-01-01

    The RIKEN integrated database of mammals (http://scinets.org/db/mammal) is the official undertaking to integrate its mammalian databases produced from multiple large-scale programs that have been promoted by the institute. The database integrates not only RIKEN's original databases, such as FANTOM, the ENU mutagenesis program, the RIKEN Cerebellar Development Transcriptome Database and the Bioresource Database, but also imported data from public databases, such as Ensembl, MGI and biomedical ontologies. Our integrated database has been implemented on the infrastructure of publication medium for databases, termed SciNetS/SciNeS, or the Scientists' Networking System, where the data and metadata are structured as a semantic web and are downloadable in various standardized formats. The top-level ontology-based implementation of mammal-related data directly integrates the representative knowledge and individual data records in existing databases to ensure advanced cross-database searches and reduced unevenness of the data management operations. Through the development of this database, we propose a novel methodology for the development of standardized comprehensive management of heterogeneous data sets in multiple databases to improve the sustainability, accessibility, utility and publicity of the data of biomedical information.

  3. Taxon-specific response of marine nitrogen fixers to elevated carbon dioxide concentrations

    NASA Astrophysics Data System (ADS)

    Hutchins, David A.; Fu, Fei-Xue; Webb, Eric A.; Walworth, Nathan; Tagliabue, Alessandro

    2013-09-01

    Much of the bioavailable nitrogen that supports open ocean food webs and biogeochemical cycles is fixed from the atmosphere by marine cyanobacteria of the genera Trichodesmium and Crocosphaera. In previous experiments carried out with a limited set of cyanobacterial isolates, rates of cyanobacterial nitrogen fixation were shown to increase with carbon dioxide concentrations. Here, we report results from a series of laboratory experiments in which we grew seven strains of Trichodesmium and Crocosphaera from the Atlantic and Pacific oceans under a wide range of carbon dioxide concentrations, and monitored rates of nitrogen fixation and growth. We document large, strain-specific differences in the relationship between nitrogen fixation and carbon dioxide concentration, suggesting that individual strains within each genus are adapted to grow and fix nitrogen at different concentrations of carbon dioxide. We apply kinetic constants from the individual carbon dioxide response curves to an illustrative biogeochemical model of the ocean in 2100, which suggests that strains adapted to high carbon dioxide concentrations could potentially be favoured in a future acidified ocean. We suggest that surface ocean carbon dioxide concentrations could constitute a previously unrecognized selective force that shapes the community composition and diversity of nitrogen-fixing cyanobacteria.

  4. The Evolution of Brains from Early Mammals to Humans.

    PubMed

    Kaas, Jon H

    2013-01-01

    The large size and complex organization of the human brain makes it unique among primate brains. In particular, the neocortex constitutes about 80% of the brain, and this cortex is subdivided into a large number of functionally specialized regions, the cortical areas. Such a brain mediates accomplishments and abilities unmatched by any other species. How did such a brain evolve? Answers come from comparative studies of the brains of present-day mammals and other vertebrates in conjunction with information about brain sizes and shapes from the fossil record, studies of brain development, and principles derived from studies of scaling and optimal design. Early mammals were small, with small brains, an emphasis on olfaction, and little neocortex. Neocortex was transformed from the single layer of output pyramidal neurons of the dorsal cortex of earlier ancestors to the six layers of all present-day mammals. This small cap of neocortex was divided into 20-25 cortical areas, including primary and some of the secondary sensory areas that characterize neocortex in nearly all mammals today. Early placental mammals had a corpus callosum connecting the neocortex of the two hemispheres, a primary motor area, M1, and perhaps one or more premotor areas. One line of evolution, Euarchontoglires, led to present-day primates, tree shrews, flying lemurs, rodents and rabbits. Early primates evolved from small-brained, nocturnal, insect-eating mammals with an expanded region of temporal visual cortex. These early nocturnal primates were adapted to the fine branch niche of the tropical rainforest by having an even more expanded visual system that mediated visually guided reaching and grasping of insects, small vertebrates, and fruits. Neocortex was greatly expanded, and included an array of cortical areas that characterize neocortex of all living primates. Specializations of the visual system included new visual areas that contributed to a dorsal stream of visuomotor processing in a

  5. The Evolution of Brains from Early Mammals to Humans

    PubMed Central

    Kaas, Jon H.

    2012-01-01

    The large size and complex organization of the human brain makes it unique among primate brains. In particular, the neocortex constitutes about 80% of the brain, and this cortex is subdivided into a large number of functionally specialized regions, the cortical areas. Such a brain mediates accomplishments and abilities unmatched by any other species. How did such a brain evolve? Answers come from comparative studies of the brains of present-day mammals and other vertebrates in conjunction with information about brain sizes and shapes from the fossil record, studies of brain development, and principles derived from studies of scaling and optimal design. Early mammals were small, with small brains, an emphasis on olfaction, and little neocortex. Neocortex was transformed from the single layer of output pyramidal neurons of the dorsal cortex of earlier ancestors to the six layers of all present-day mammals. This small cap of neocortex was divided into 20–25 cortical areas, including primary and some of the secondary sensory areas that characterize neocortex in nearly all mammals today. Early placental mammals had a corpus callosum connecting the neocortex of the two hemispheres, a primary motor area, M1, and perhaps one or more premotor areas. One line of evolution, Euarchontoglires, led to present-day primates, tree shrews, flying lemurs, rodents and rabbits. Early primates evolved from small-brained, nocturnal, insect-eating mammals with an expanded region of temporal visual cortex. These early nocturnal primates were adapted to the fine branch niche of the tropical rainforest by having an even more expanded visual system that mediated visually guided reaching and grasping of insects, small vertebrates, and fruits. Neocortex was greatly expanded, and included an array of cortical areas that characterize neocortex of all living primates. Specializations of the visual system included new visual areas that contributed to a dorsal stream of visuomotor processing in a

  6. DSM-IV Antisocial Personality Disorder and Conduct Disorder: Evidence for Taxonic Structures Among Individuals With and Without Substance Use Disorders in the General Population

    PubMed Central

    Kerridge, Bradley T; Saha, Tulshi D; Hasin, Deborah S

    2014-01-01

    Objective: The categorical-dimensional status of DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) conduct disorder (CD) and antisocial personality disorder (ASPD) is a source of controversy. This study examined whether the underlying structure of DSM-IV CD and ASPD was dimensional or categorical (taxonic) among individuals with and without substance use disorders. Method: Using a national large representative survey of U.S. adults (n = 43,093), taxometric analyses of DSM-IV CD and ASPD diagnostic criteria were conducted on the total sample and among those with and without substance use disorders. Results: Results of three taxometric procedures were consistent in showing that the structures underlying DSM-IV CD and ASPD were clearly taxonic in the total sample and among individuals with and without substance use disorders. Comparison curve fit indices exceeded 0.57 for each model. Conclusions: Taxonic findings of the present study were in contrast to the dimensional results of prior taxometric research among incarcerated samples with substantial comorbidity of antisocial syndromes and substance use disorders. Results supported the categorical representation and diagnostic thresholds of ASPD and CD as defined in DSM-IV and DSM-5. That the structure of ASPD and CD may be taxonic suggests that further research on these disorders use group comparative designs in which samples with and without these disorders are compared in terms of sociodemographic and clinical correlates, comorbidity, and treatment utilization. The taxonic structure of ASPD and CD may contribute to future research on causal processes through which these antisocial syndromes develop. PMID:24766762

  7. Comparative analysis of mitochondrial genomes in Diplura (hexapoda, arthropoda): taxon sampling is crucial for phylogenetic inferences.

    PubMed

    Chen, Wan-Jun; Koch, Markus; Mallatt, Jon M; Luan, Yun-Xia

    2014-01-01

    Two-pronged bristletails (Diplura) are traditionally classified into three major superfamilies: Campodeoidea, Projapygoidea, and Japygoidea. The interrelationships of these three superfamilies and the monophyly of Diplura have been much debated. Few previous studies included Projapygoidea in their phylogenetic considerations, and its position within Diplura still is a puzzle from both morphological and molecular points of view. Until now, no mitochondrial genome has been sequenced for any projapygoid species. To fill in this gap, we determined and annotated the complete mitochondrial genome of Octostigma sinensis (Octostigmatidae, Projapygoidea), and of three more dipluran species, one each from the Campodeidae, Parajapygidae, and Japygidae. All four newly sequenced dipluran mtDNAs encode the same set of genes in the same gene order as shared by most crustaceans and hexapods. Secondary structure truncations have occurred in trnR, trnC, trnS1, and trnS2, and the reduction of transfer RNA D-arms was found to be taxonomically correlated, with Campodeoidea having experienced the most reduction. Partitioned phylogenetic analyses, based on both amino acids and nucleotides of the protein-coding genes plus the ribosomal RNA genes, retrieve significant support for a monophyletic Diplura within Pancrustacea, with Projapygoidea more closely related to Campodeoidea than to Japygoidea. Another key finding is that monophyly of Diplura cannot be recovered unless Projapygoidea is included in the phylogenetic analyses; this explains the dipluran polyphyly found by past mitogenomic studies. Including Projapygoidea increased the sampling density within Diplura and probably helped by breaking up a long-branch-attraction artifact. This finding provides an example of how proper sampling is significant for phylogenetic inference.

  8. Small mammals as monitors of environmental contaminants.

    PubMed

    Talmage, S S; Walton, B T

    1991-01-01

    The merit of using small mammals as monitors of environmental contaminants was assessed using data from the published literature. Information was located on 35 species of small mammals from 7 families used to monitor heavy metals, radionuclides, and organic chemicals at mine sites, industrial areas, hazardous and radioactive waste disposal sites, and agricultural and forested land. To document foodchain transfer of chemicals, concentrations in soil, vegetation, and invertebrates, where available, were included. The most commonly trapped North American species were Peromyscus leucopus, Blarina brevicauda, and Microtus pennsylvanicus. In these species, exposure to chemicals was determined from tissue residue analyses, biochemical assays, and cytogenetic assays. Where enough information was available, suitable target tissues, or biological assays for specific chemicals were noted. In general, there was a relationship between concentrations of contaminants in the soil or food, and concentrations in target tissues of several species. This relationship was most obvious for the nonessential heavy metals, cadmium, lead, and mercury and for fluoride. Kidney was the single best tissue for residue analyses of inorganic contaminants. However, bone should be the tissue of choice for both lead and fluorine. Exposure to lead was also successfully documented using biochemical and histopathological endpoints. Bone was the tissue of choice for exposure to 90Sr, whereas muscle was an appropriate tissue for 137Cs. For organic contaminants, exposure endpoints depended on the chemical(s) of concern. Liver and whole-body residue analyses, as well as enzyme changes, organ histology, genotoxicity, and, in one case, population dynamics, were successfully used to document exposure to these contaminants. Based on information in these studies, each species' suitability as a monitor for a specific contaminant or type of contaminant was evaluated and subsequently ranked. A relationship between

  9. Small mammals as monitors of environmental contaminants.

    PubMed

    Talmage, S S; Walton, B T

    1991-01-01

    The merit of using small mammals as monitors of environmental contaminants was assessed using data from the published literature. Information was located on 35 species of small mammals from 7 families used to monitor heavy metals, radionuclides, and organic chemicals at mine sites, industrial areas, hazardous and radioactive waste disposal sites, and agricultural and forested land. To document foodchain transfer of chemicals, concentrations in soil, vegetation, and invertebrates, where available, were included. The most commonly trapped North American species were Peromyscus leucopus, Blarina brevicauda, and Microtus pennsylvanicus. In these species, exposure to chemicals was determined from tissue residue analyses, biochemical assays, and cytogenetic assays. Where enough information was available, suitable target tissues, or biological assays for specific chemicals were noted. In general, there was a relationship between concentrations of contaminants in the soil or food, and concentrations in target tissues of several species. This relationship was most obvious for the nonessential heavy metals, cadmium, lead, and mercury and for fluoride. Kidney was the single best tissue for residue analyses of inorganic contaminants. However, bone should be the tissue of choice for both lead and fluorine. Exposure to lead was also successfully documented using biochemical and histopathological endpoints. Bone was the tissue of choice for exposure to 90Sr, whereas muscle was an appropriate tissue for 137Cs. For organic contaminants, exposure endpoints depended on the chemical(s) of concern. Liver and whole-body residue analyses, as well as enzyme changes, organ histology, genotoxicity, and, in one case, population dynamics, were successfully used to document exposure to these contaminants. Based on information in these studies, each species' suitability as a monitor for a specific contaminant or type of contaminant was evaluated and subsequently ranked. A relationship between

  10. Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park.

    PubMed

    Dorcas, Michael E; Willson, John D; Reed, Robert N; Snow, Ray W; Rochford, Michael R; Miller, Melissa A; Meshaka, Walter E; Andreadis, Paul T; Mazzotti, Frank J; Romagosa, Christina M; Hart, Kristen M

    2012-02-14

    Invasive species represent a significant threat to global biodiversity and a substantial economic burden. Burmese pythons, giant constricting snakes native to Asia, now are found throughout much of southern Florida, including all of Everglades National Park (ENP). Pythons have increased dramatically in both abundance and geographic range since 2000 and consume a wide variety of mammals and birds. Here we report severe apparent declines in mammal populations that coincide temporally and spatially with the proliferation of pythons in ENP. Before 2000, mammals were encountered frequently during nocturnal road surveys within ENP. In contrast, road surveys totaling 56,971 km from 2003-2011 documented a 99.3% decrease in the frequency of raccoon observations, decreases of 98.9% and 87.5% for opossum and bobcat observations, respectively, and failed to detect rabbits. Road surveys also revealed that these species are more common in areas where pythons have been discovered only recently and are most abundant outside the python's current introduced range. These findings suggest that predation by pythons has resulted in dramatic declines in mammals within ENP and that introduced apex predators, such as giant constrictors, can exert significant top-down pressure on prey populations. Severe declines in easily observed and/or common mammals, such as raccoons and bobcats, bode poorly for species of conservation concern, which often are more difficult to sample and occur at lower densities.

  11. Environmental contamination and marine mammals in coastal waters from Argentina: an overview.

    PubMed

    Marcovecchio, J E; Gerpe, M S; Bastida, R O; Rodríguez, D H; Morón, S G

    1994-09-16

    Environmental contamination become an increasing global problem. Different scientific strategies have been developed in order to assess the impact of pollutants on marine ecosystems. The distribution of toxic contaminants in tissues of different marine mammal species--both cetaceans and pinnipeds--has been studied in many ecosystems, as well as several related ecological processes, like pollutant accumulation or transfer through the food web. A research program directed towards evaluating the occurrence of pollutants in marine mammals from the coastal waters of Argentina (southwestern Atlantic Ocean) has been developed since 1985, and includes the study of heavy metal contents in stranded or incidentally caught animals. The marine mammal species studied during this period were: the seals Otaria flavescens and Arctocephalus australis, and small cetaceans Tursiops gephyreus, Pontoporia blainvillei, Kogia breviceps and Ziphius cavirostris. In most of the cases, high contents of heavy metals (total mercury, cadmium, zinc, and copper) have been recorded. Moreover, liver showed the maximum capability for accumulation of heavy metals in all studied species. The biological and ecological characteristics of each species of the above-mentioned marine mammals (feeding habits, age, migratory pathways, or sex) contributed to the understanding of the metal sources. Considering the results as obtained during the study period it can be assumed that: (1) The global distribution of toxic contaminants also affects the southwestern Atlantic Ocean ecosystems, and (2) Marine mammals could be appropriate bioindicator species in order to assess this kind of environmental problem. PMID:7973603

  12. Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park

    PubMed Central

    Dorcas, Michael E.; Willson, John D.; Reed, Robert N.; Snow, Ray W.; Rochford, Michael R.; Miller, Melissa A.; Meshaka, Walter E.; Andreadis, Paul T.; Mazzotti, Frank J.; Romagosa, Christina M.; Hart, Kristen M.

    2012-01-01

    Invasive species represent a significant threat to global biodiversity and a substantial economic burden. Burmese pythons, giant constricting snakes native to Asia, now are found throughout much of southern Florida, including all of Everglades National Park (ENP). Pythons have increased dramatically in both abundance and geographic range since 2000 and consume a wide variety of mammals and birds. Here we report severe apparent declines in mammal populations that coincide temporally and spatially with the proliferation of pythons in ENP. Before 2000, mammals were encountered frequently during nocturnal road surveys within ENP. In contrast, road surveys totaling 56,971 km from 2003–2011 documented a 99.3% decrease in the frequency of raccoon observations, decreases of 98.9% and 87.5% for opossum and bobcat observations, respectively, and failed to detect rabbits. Road surveys also revealed that these species are more common in areas where pythons have been discovered only recently and are most abundant outside the python's current introduced range. These findings suggest that predation by pythons has resulted in dramatic declines in mammals within ENP and that introduced apex predators, such as giant constrictors, can exert significant top-down pressure on prey populations. Severe declines in easily observed and/or common mammals, such as raccoons and bobcats, bode poorly for species of conservation concern, which often are more difficult to sample and occur at lower densities. PMID:22308381

  13. Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park

    USGS Publications Warehouse

    Dorcas, Michael E.; Wilson, John D.; Reed, Robert N.; Snow, Ray W.; Rochford, Michael R.; Miller, Melissa A.; Meshaka, Walter E.; Andreadis, Paul T.; Mazzotti, Frank J.; Romagosa, Christina M.; Hart, Kristen M.

    2012-01-01

    Invasive species represent a significant threat to global biodiversity and a substantial economic burden. Burmese pythons, giant constricting snakes native to Asia, now are found throughout much of southern Florida, including all of Everglades National Park (ENP). Pythons have increased dramatically in both abundance and geographic range since 2000 and consume a wide variety of mammals and birds. Here we report severe apparent declines in mammal populations that coincide temporally and spatially with the proliferation of pythons in ENP. Before 2000, mammals were encountered frequently during nocturnal road surveys within ENP. In contrast, road surveys totaling 56,971 km from 2003–2011 documented a 99.3% decrease in the frequency of raccoon observations, decreases of 98.9% and 87.5% for opossum and bobcat observations, respectively, and failed to detect rabbits. Road surveys also revealed that these species are more common in areas where pythons have been discovered only recently and are most abundant outside the python's current introduced range. These findings suggest that predation by pythons has resulted in dramatic declines in mammals within ENP and that introduced apex predators, such as giant constrictors, can exert significant top-down pressure on prey populations. Severe declines in easily observed and/or common mammals, such as raccoons and bobcats, bode poorly for species of conservation concern, which often are more difficult to sample and occur at lower densities.

  14. Small mammal distribution and diversity in a plague endemic area in West Usambara Mountains, Tanzania.

    PubMed

    Ralaizafisoloarivony, Njaka A; Kimaro, Didas N; Kihupi, Nganga I; Mulungu, Loth S; Leirs, Herwig; Msanya, Balthazar M; Deckers, Jozef A; Gulinck, Hubert

    2014-07-01

    Small mammals play a role in plague transmission as hosts in all plague endemic areas. Information on distribution and diversity of small mammals is therefore important for plague surveillance and control in such areas. The objective of this study was to investigate small mammals' diversity and their distribution in plague endemic area in the West Usambara Mountains in north-eastern Tanzania. Landsat images and field surveys were used to select trapping locations in different landscapes. Three landscapes with different habitats were selected for trapping of small mammals. Three types of trap were used in order to maximise the number of species captured. In total, 188 animals and thirteen species were captured in 4,905 trap nights. Praomys delectorum and Mastomys natalensis both reported as plague hosts comprised 50% of all the animals trapped. Trap success increased with altitude. Species diversity was higher in plantation forest followed by shrub, compared to other habitats, regardless of landscape type. It would therefore seem that chances of plague transmission from small mammals to humans are much higher under shrub, natural and plantation forest habitats.

  15. Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park.

    PubMed

    Dorcas, Michael E; Willson, John D; Reed, Robert N; Snow, Ray W; Rochford, Michael R; Miller, Melissa A; Meshaka, Walter E; Andreadis, Paul T; Mazzotti, Frank J; Romagosa, Christina M; Hart, Kristen M

    2012-02-14

    Invasive species represent a significant threat to global biodiversity and a substantial economic burden. Burmese pythons, giant constricting snakes native to Asia, now are found throughout much of southern Florida, including all of Everglades National Park (ENP). Pythons have increased dramatically in both abundance and geographic range since 2000 and consume a wide variety of mammals and birds. Here we report severe apparent declines in mammal populations that coincide temporally and spatially with the proliferation of pythons in ENP. Before 2000, mammals were encountered frequently during nocturnal road surveys within ENP. In contrast, road surveys totaling 56,971 km from 2003-2011 documented a 99.3% decrease in the frequency of raccoon observations, decreases of 98.9% and 87.5% for opossum and bobcat observations, respectively, and failed to detect rabbits. Road surveys also revealed that these species are more common in areas where pythons have been discovered only recently and are most abundant outside the python's current introduced range. These findings suggest that predation by pythons has resulted in dramatic declines in mammals within ENP and that introduced apex predators, such as giant constrictors, can exert significant top-down pressure on prey populations. Severe declines in easily observed and/or common mammals, such as raccoons and bobcats, bode poorly for species of conservation concern, which often are more difficult to sample and occur at lower densities. PMID:22308381

  16. Environmental contamination and marine mammals in coastal waters from Argentina: an overview.

    PubMed

    Marcovecchio, J E; Gerpe, M S; Bastida, R O; Rodríguez, D H; Morón, S G

    1994-09-16

    Environmental contamination become an increasing global problem. Different scientific strategies have been developed in order to assess the impact of pollutants on marine ecosystems. The distribution of toxic contaminants in tissues of different marine mammal species--both cetaceans and pinnipeds--has been studied in many ecosystems, as well as several related ecological processes, like pollutant accumulation or transfer through the food web. A research program directed towards evaluating the occurrence of pollutants in marine mammals from the coastal waters of Argentina (southwestern Atlantic Ocean) has been developed since 1985, and includes the study of heavy metal contents in stranded or incidentally caught animals. The marine mammal species studied during this period were: the seals Otaria flavescens and Arctocephalus australis, and small cetaceans Tursiops gephyreus, Pontoporia blainvillei, Kogia breviceps and Ziphius cavirostris. In most of the cases, high contents of heavy metals (total mercury, cadmium, zinc, and copper) have been recorded. Moreover, liver showed the maximum capability for accumulation of heavy metals in all studied species. The biological and ecological characteristics of each species of the above-mentioned marine mammals (feeding habits, age, migratory pathways, or sex) contributed to the understanding of the metal sources. Considering the results as obtained during the study period it can be assumed that: (1) The global distribution of toxic contaminants also affects the southwestern Atlantic Ocean ecosystems, and (2) Marine mammals could be appropriate bioindicator species in order to assess this kind of environmental problem.

  17. Development, polymorphism, and cross-taxon utility of EST-SSR markers from safflower (Carthamus tinctorius L.).

    PubMed

    Chapman, Mark A; Hvala, John; Strever, Jason; Matvienko, Marta; Kozik, Alexander; Michelmore, Richard W; Tang, Shunxue; Knapp, Steven J; Burke, John M

    2009-12-01

    Due to their highly polymorphic and codominant nature, simple-sequence repeat (SSR) markers are a common choice for assaying genetic diversity and genetic mapping. In this paper, we describe the generation of an expressed-sequence tag (EST) collection for the oilseed crop safflower and the subsequent development of EST-SSR markers for the genetic analysis of safflower and related species. We assembled 40,874 reads into 19,395 unigenes, of which 4,416 (22.8%) contained at least one SSR. Primer pairs were developed and tested for 384 of these loci, resulting in a collection of 104 polymorphic markers that amplify reliably across 27 accessions (3 species) of the genus Carthamus. These markers exhibited a high level of polymorphism, with an average of 6.0 +/- 0.4 alleles per locus and an average gene diversity of 0.54 +/- 0.03 across Carthamus species. In terms of cross-taxon transferability, 50% of these primer pairs produced an amplicon in at least one other species in the Asteraceae, and 28% produced an amplicon in at least one species outside the safflower subfamily (i.e., lettuce, sunflower, and/or Gerbera). These markers represent a valuable resource for the genetic analysis of safflower and related species, and also have the potential to facilitate comparative map-based analyses across a broader array of taxa within the Asteraceae.

  18. Taxon-specific metagenomics of Trichoderma reveals a narrow community of opportunistic species that regulate each other’s development

    PubMed Central

    Friedl, Martina A.

    2012-01-01

    In this paper, we report on the in situ diversity of the mycotrophic fungus Trichoderma (teleomorph Hypocrea, Ascomycota, Dikarya) revealed by a taxon-specific metagenomic approach. We designed a set of genus-specific internal transcribed spacer (ITS)1 and ITS2 rRNA primers and constructed a clone library containing 411 molecular operational taxonomic units (MOTUs). The overall species composition in the soil of the two distinct ecosystems in the Danube floodplain consisted of 15 known species and two potentially novel taxa. The latter taxa accounted for only 1.5 % of all MOTUs, suggesting that almost no hidden or uncultivable Hypocrea/Trichoderma species are present at least in these temperate forest soils. The species were unevenly distributed in vertical soil profiles although no universal factors controlling the distribution of all of them (chemical soil properties, vegetation type and affinity to rhizosphere) were revealed. In vitro experiments simulating infrageneric interactions between the pairs of species that were detected in the same soil horizon showed a broad spectrum of reactions from very strong competition over neutral coexistence to the pronounced synergism. Our data suggest that only a relatively small portion of Hypocrea/Trichoderma species is adapted to soil as a habitat and that the interaction between these species should be considered in a screening for Hypocrea/Trichoderma as an agent(s) of biological control of pests. PMID:22075025

  19. Phosphorus Availability, Phytoplankton Community Dynamics, and Taxon-Specific Phosphorus Status in the Gulf of Aqaba, Red Sea

    NASA Astrophysics Data System (ADS)

    Mackey, K. R.; Labiosa, R. G.; Calhoun, M.; Street, J. H.; Post, A. F.; Paytan, A.

    2006-12-01

    The relationships among phytoplankton taxon-specific phosphorus-status, phytoplankton community composition, and nutrient levels were assessed over three seasons in the Gulf of Aqaba, Red Sea. During summer and fall, stratified surface waters were depleted of nutrients and picophytoplankton populations comprised the majority of cells (80% and 88% respectively). In winter, surface nutrient concentrations were higher and larger phytoplankton were more abundant (63%). Cell specific alkaline phosphatase activity (APA) derived from enzyme labeled fluorescence was consistently low (less than 5%) in the picophytoplankton throughout the year, whereas larger cells expressed elevated APA during the summer and fall but less in the winter. A nutrient addition bioassay during the fall showed that, relative to control, APA was reduced by half in larger cells following addition of orthophosphate, whereas the APA of picophytoplankton remained low (less than 1%) across all treatments and the control. These results indicate that the most abundant phytoplankton are not limited by orthophosphate and only some subpopulations (particularly of larger cells) exhibit orthophosphate-limitation throughout the year. Our results indicate that orthophosphate availability influences phytoplankton ecology, correlating with shifts in phytoplankton community structure and the nutrient status of individual cells. The role of dissolved organic phosphorus as an important phosphorus source for marine phytoplankton in oligotrophic settings and the need for evaluating nutrient limitation at the taxa and/or single cell level (rather than inferring it from nutrient concentrations and ratios or bulk enzyme activity measurements) are highlighted.

  20. Dispersal and diversity in the earliest North American sauropodomorph dinosaurs, with a description of a new taxon.

    PubMed

    Rowe, Timothy B; Sues, Hans-Dieter; Reisz, Robert R

    2011-04-01

    Sauropodomorph dinosaurs originated in the Southern Hemisphere in the Middle or Late Triassic and are commonly portrayed as spreading rapidly to all corners of Pangaea as part of a uniform Late Triassic to Early Jurassic cosmopolitan dinosaur fauna. Under this model, dispersal allegedly inhibited dinosaurian diversification, while vicariance and local extinction enhanced it. However, apomorphy-based analyses of the known fossil record indicate that sauropodomorphs were absent in North America until the Early Jurassic, reframing the temporal context of their arrival. We describe a new taxon from the Kayenta Formation of Arizona that comprises the third diagnosable sauropodomorph from the Early Jurassic of North America. We analysed its relationships to test whether sauropodomorphs reached North America in a single sweepstakes event or in separate dispersals. Our finding of separate arrivals by all three taxa suggests dispersal as a chief factor in dinosaurian diversification during at least the early Mesozoic. It questions whether a 'cosmopolitan' dinosaur fauna ever existed, and corroborates that vicariance, extinction and dispersal did not operate uniformly in time or under uniform conditions during the Mesozoic. Their relative importance is best measured in narrow time slices and circumscribed geographical regions.

  1. Dispersal and diversity in the earliest North American sauropodomorph dinosaurs, with a description of a new taxon

    PubMed Central

    Rowe, Timothy B.; Sues, Hans-Dieter; Reisz, Robert R.

    2011-01-01

    Sauropodomorph dinosaurs originated in the Southern Hemisphere in the Middle or Late Triassic and are commonly portrayed as spreading rapidly to all corners of Pangaea as part of a uniform Late Triassic to Early Jurassic cosmopolitan dinosaur fauna. Under this model, dispersal allegedly inhibited dinosaurian diversification, while vicariance and local extinction enhanced it. However, apomorphy-based analyses of the known fossil record indicate that sauropodomorphs were absent in North America until the Early Jurassic, reframing the temporal context of their arrival. We describe a new taxon from the Kayenta Formation of Arizona that comprises the third diagnosable sauropodomorph from the Early Jurassic of North America. We analysed its relationships to test whether sauropodomorphs reached North America in a single sweepstakes event or in separate dispersals. Our finding of separate arrivals by all three taxa suggests dispersal as a chief factor in dinosaurian diversification during at least the early Mesozoic. It questions whether a ‘cosmopolitan’ dinosaur fauna ever existed, and corroborates that vicariance, extinction and dispersal did not operate uniformly in time or under uniform conditions during the Mesozoic. Their relative importance is best measured in narrow time slices and circumscribed geographical regions. PMID:20926438

  2. In Situ Detection of Freshwater Fungi in an Alpine Stream by New Taxon-Specific Fluorescence In Situ Hybridization Probes▿

    PubMed Central

    Baschien, Christiane; Manz, Werner; Neu, Thomas R.; Marvanová, Ludmila; Szewzyk, Ulrich

    2008-01-01

    New rRNA-targeting oligonucleotide probes permitted the fluorescence in situ hybridization (FISH) identification of freshwater fungi in an Austrian second-order alpine stream. Based on computer-assisted comparative sequence analysis, nine taxon-specific probes were designed and evaluated by whole-fungus hybridizations. Oligonucleotide probe MY1574, specific for a wide range of Eumycota, and the genus (Tetracladium)-specific probe TCLAD1395, as well as the species-specific probes ALacumi1698 (Alatospora acuminata), TRIang322 (Tricladium angulatum), and Alongi340 (Anguillospora longissima), are targeted against 18S rRNA, whereas probes TmarchB10, TmarchC1_1, TmarchC1_2, and AlongiB16 are targeted against the 28S rRNA of Tetracladium marchalianum and Anguillospora longissima, respectively. After 2 weeks and 3 months of exposure of polyethylene slides in the stream, attached germinating conidia and growing hyphae of freshwater fungi were accessible for FISH. Growing hyphae and germinating conidia on leaves and in membrane cages were also visualized by the new FISH probes. PMID:18776035

  3. Variability of Sequence Surrounding the Xist Gene in Rodents Suggests Taxon-Specific Regulation of X Chromosome Inactivation

    PubMed Central

    Shevchenko, Alexander I.; Malakhova, Anastasia A.; Elisaphenko, Eugeny A.; Mazurok, Nina A.; Nesterova, Tatyana B.; Brockdorff, Neil; Zakian, Suren M.

    2011-01-01

    One of the two X chromosomes in female mammalian cells is subject to inactivation (XCI) initiated by the Xist gene. In this study, we examined in rodents (voles and rat) the conservation of the microsatellite region DXPas34, the Tsix gene (antisense counterpart of Xist), and enhancer Xite that have been shown to flank Xist and regulate XCI in mouse. We have found that mouse regions of the Tsix gene major promoter and minisatellite repeat DXPas34 are conserved among rodents. We have also shown that in voles and rat the region homologous to the mouse Tsix major promoter, initiates antisense to Xist transcription and terminates around the Xist gene start site as is observed with mouse Tsix. A conservation of Tsix expression pattern in voles, rat and mice suggests a crucial role of the antisense transcription in regulation of Xist and XIC in rodents. Most surprisingly, we have found that voles lack the regions homologous to the regulatory element Xite, which is instead replaced with the Slc7a3 gene that is unassociated with the X-inactivation centre in any other eutherians studied. Furthermore, we have not identified any transcription that could have the same functions as murine Xite in voles. Overall, our data show that not all the functional elements surrounding Xist in mice are well conserved even within rodents, thereby suggesting that the regulation of XCI may be at least partially taxon-specific. PMID:21826206

  4. Mammal madness: is the mammal tree of life not yet resolved?

    PubMed

    Foley, Nicole M; Springer, Mark S; Teeling, Emma C

    2016-07-19

    Most molecular phylogenetic studies place all placental mammals into four superordinal groups, Laurasiatheria (e.g. dogs, bats, whales), Euarchontoglires (e.g. humans, rodents, colugos), Xenarthra (e.g. armadillos, anteaters) and Afrotheria (e.g. elephants, sea cows, tenrecs), and estimate that these clades last shared a common ancestor 90-110 million years ago. This phylogeny has provided a framework for numerous functional and comparative studies. Despite the high level of congruence among most molecular studies, questions still remain regarding the position and divergence time of the root of placental mammals, and certain 'hard nodes' such as the Laurasiatheria polytomy and Paenungulata that seem impossible to resolve. Here, we explore recent consensus and conflict among mammalian phylogenetic studies and explore the reasons for the remaining conflicts. The question of whether the mammal tree of life is or can be ever resolved is also addressed.This article is part of the themed issue 'Dating species divergences using rocks and clocks'.

  5. Predation, Competition, and Abiotic Disturbance: Population Dynamics of Small Mammals

    SciTech Connect

    Yunger, John A.; /Northern Illinois U. /Northern Illinois U.

    1996-01-01

    Predation and food availability have been implicated in annual non-cyclic fluctuations of vertebrate prey at mid-latitudes. The timing and magnitude of these factors are unclear due to a lack of large-scale field experiments, little attention to interactions, and a failure to closely link vertebrate predators with their prey. From October 1992 to January 1996, small mammal populations were censused on eight 0.6 ha plots at monthly intervals in a 32-ha prairie restoration at Fermi National Accelerator Laboratory, Illinois. Terrestrial vertebrate predators were excluded after July 1993 from four of the eight plots and canid diets monitored. Both terrestrial and avian vertebrate predators were excluded in March 1994. During 1993 small mammal densities (i.e., Microtus Pennsylvanicus, Peromyscus leucopus, and P. maniculatus) were relatively high. Following peak densities in late summer, Microtus numbers wer 2-3x greater on exclusion plots relative to controls due to preferential selection of Microtus by canids, as reflected in dits. Following an ice-storm and crash in small mammal numbers (particularly Microtus), vertebrate predator exclusion had no detectable effect on P. leucopus numbers, probably due to an abundance of alternative prey (i.e., Sylvilagus floridanus). Meadow vole numbers began to increase in Fall 1995, and a numerical effect of predator exclusion, similar to that in 1993, was observed. Predator exclusion had no detectable effect on the movements and spatial patterns of Microtus during 1993. There was a significant decrease in home range and a significant increase in home range overlap for P. leucopus on the predator exclusion plots. The change in spatial behavior may be due to interspecific competition with Microtus resulting from increased densities on exclusion plots. Thus, predators had an indirect effect on P. leucopus spatial patterns mediated through M. Pennsylvanicus. The role of food limitation was studied using natural and manipulative

  6. Mammal mortality at Arizona, California, and Nevada gold mines using cyanide extraction

    USGS Publications Warehouse

    Clark, D.R.; Hothem, R.L.

    1991-01-01

    Five-hundred nineteen mammals were reported dead at cyanide-extraction gold mines in Arizona [USA], California, and Nevada from 1984 through 1989. Most numerous were rodents (34.9%) and bats (33.7%); 'bat' was the most often reported category among 24 species or species groups. There are an estimated 160 cyanide-extraction gold mines in these three states, and the number is increasing. Ten mammal species listed as endangered, threatened, rare, protected, or species of special concern are known to have cyanide-extraction gold mines within their geographic ranges.

  7. Age-related variation in immunity in a wild mammal population

    PubMed Central

    Nussey, Daniel H; Watt, Kathryn; Pilkington, Jill G; Zamoyska, Rose; McNeilly, Tom N

    2012-01-01

    Summary Age-related changes in immunity are well documented in humans and laboratory mammals. Using blood samples collected from wild Soay sheep, we show that pronounced differences in T-cell subsets and inflammatory markers amongst age classes are also evident under natural conditions. These shifts parallel those observed in mammals experiencing protected environments. We found progressive declines in the proportion of naïve CD4 T cells with age, a precipitous drop in γδ T cells after the second year of life and an increase in acute phase protein levels amongst geriatric sheep. Our findings suggest immune aging patterns observed in laboratory and domestic mammals may generalize to more complex, challenging environments and could have fitness costs under natural conditions. PMID:22107028

  8. Phylogeny, niche conservatism and the latitudinal diversity gradient in mammals.

    PubMed

    Buckley, Lauren B; Davies, T Jonathan; Ackerly, David D; Kraft, Nathan J B; Harrison, Susan P; Anacker, Brian L; Cornell, Howard V; Damschen, Ellen I; Grytnes, John-Avid; Hawkins, Bradford A; McCain, Christy M; Stephens, Patrick R; Wiens, John J

    2010-07-22

    Biologists have long searched for mechanisms responsible for the increase in species richness with decreasing latitude. The strong correlation between species richness and climate is frequently interpreted as reflecting a causal link via processes linked to energy or evolutionary rates. Here, we investigate how the aggregation of clades, as dictated by phylogeny, can give rise to significant climate-richness gradients without gradients in diversification or environmental carrying capacity. The relationship between climate and species richness varies considerably between clades, regions and time periods in a global-scale phylogenetically informed analysis of all terrestrial mammal species. Many young clades show negative richness-temperature slopes (more species at cooler temperatures), with the ages of these clades coinciding with the expansion of temperate climate zones in the late Eocene. In carnivores, we find steeply positive richness-temperature slopes in clades with restricted distributions and tropical origins (e.g. cat clade), whereas widespread, temperate clades exhibit shallow, negative slopes (e.g. dog-bear clade). We show that the slope of the global climate-richness gradient in mammals is driven by aggregating Chiroptera (bats) with their Eutherian sister group. Our findings indicate that the evolutionary history should be accounted for as part of any search for causal links between environment and species richness. PMID:20335205

  9. Temporal scaling of molecular evolution in primates and other mammals.

    PubMed

    Gingerich, P D

    1986-05-01

    Molecular clocks are routinely tested for linearity using a relative rate test and routinely calibrated against the geological time scale using a single or average paleontologically determined time of divergence between living taxa. The relative rate test is a test of parallel rate equality, not a test of rate constancy. Temporal scaling provides a test of rates, where scaling coefficients of 1.0 (isochrony) represent stochastic rate constancy. The fossil record of primates and other mammals is now known in sufficient detail to provide several independent divergence times for major taxonomic groups. Molecular difference should scale negatively or isochronically (scaling coefficients less than 1.0) with divergence time: where two or more divergence times are available, molecular difference appears to scale positively (scaling coefficient greater than 1.0). A minimum of four divergence times are required for adequate statistical power in testing the linear model: scaling is significantly nonlinear and positive in six of 11 published investigations meeting this criterion. All groups studied show some slowdown in rates of molecular change over Cenozoic time. The break from constant or increasing rates during the Mesozoic to decreasing rates during the Cenozoic appears to coincide with extraordinary diversification of placental mammals at the beginning of this era. High rates of selectively neutral molecular change may be concentrated in such discrete events of evolutionary diversification.

  10. Mammals of Australia's Tropical Savannas: A Conceptual Model of Assemblage Structure and Regulatory Factors in the Kimberley Region

    PubMed Central

    Radford, Ian J.; Dickman, Christopher R.; Start, Antony N.; Palmer, Carol; Carnes, Karin; Everitt, Corrin; Fairman, Richard; Graham, Gordon; Partridge, Thalie; Thomson, Allan

    2014-01-01

    We construct a state-and-transition model for mammals in tropical savannas in northern Australia to synthesize ecological knowledge and understand mammalian declines. We aimed to validate the existence of alternative mammal assemblage states similar to those in arid Australian grasslands, and to speculate on transition triggers. Based on the arid grassland model, we hypothesized that assemblages are partitioned across rainfall gradients and between substrates. We also predicted that assemblages typical of arid regions in boom periods would be prevalent in savannas with higher and more regular rainfall. Data from eight mammal surveys from the Kimberley region, Western Australia (1994 to 2011) were collated. Survey sites were partitioned across rainfall zones and habitats. Data allowed us to identify three assemblage states: State 0:- low numbers of mammals, State II:- dominated by omnivorous rodents and State III:- dominated by rodents and larger marsupials. Unlike arid grasslands, assemblage dominance by insectivorous dasyurids (State I) did not occur in savannas. Mammal assemblages were partitioned across rainfall zones and between substrates as predicted, but—unlike arid regions—were not related strongly to yearly rainfall. Mammal assemblage composition showed high regional stability, probably related to high annual rainfall and predictable wet season resource pulses. As a consequence, we speculate that perpetually booming assemblages in savannas allow top-down control of the ecosystem, with suppression of introduced cats by the dingo, the region's top predator. Under conditions of low or erratic productivity, imposed increasingly by intense fire regimes and introduced herbivore grazing, dingoes may not limit impacts of cats on native mammals. These interacting factors may explain contemporary declines of savanna mammals as well as historical declines in arid Australia. The cat-ecosystem productivity hypothesis raised here differs from the already

  11. Mammals of Australia's tropical savannas: a conceptual model of assemblage structure and regulatory factors in the Kimberley region.

    PubMed

    Radford, Ian J; Dickman, Christopher R; Start, Antony N; Palmer, Carol; Carnes, Karin; Everitt, Corrin; Fairman, Richard; Graham, Gordon; Partridge, Thalie; Thomson, Allan

    2014-01-01

    We construct a state-and-transition model for mammals in tropical savannas in northern Australia to synthesize ecological knowledge and understand mammalian declines. We aimed to validate the existence of alternative mammal assemblage states similar to those in arid Australian grasslands, and to speculate on transition triggers. Based on the arid grassland model, we hypothesized that assemblages are partitioned across rainfall gradients and between substrates. We also predicted that assemblages typical of arid regions in boom periods would be prevalent in savannas with higher and more regular rainfall. Data from eight mammal surveys from the Kimberley region, Western Australia (1994 to 2011) were collated. Survey sites were partitioned across rainfall zones and habitats. Data allowed us to identify three assemblage states: State 0:--low numbers of mammals, State II:--dominated by omnivorous rodents and State III:--dominated by rodents and larger marsupials. Unlike arid grasslands, assemblage dominance by insectivorous dasyurids (State I) did not occur in savannas. Mammal assemblages were partitioned across rainfall zones and between substrates as predicted, but-unlike arid regions-were not related strongly to yearly rainfall. Mammal assemblage composition showed high regional stability, probably related to high annual rainfall and predictable wet season resource pulses. As a consequence, we speculate that perpetually booming assemblages in savannas allow top-down control of the ecosystem, with suppression of introduced cats by the dingo, the region's top predator. Under conditions of low or erratic productivity, imposed increasingly by intense fire regimes and introduced herbivore grazing, dingoes may not limit impacts of cats on native mammals. These interacting factors may explain contemporary declines of savanna mammals as well as historical declines in arid Australia. The cat-ecosystem productivity hypothesis raised here differs from the already-articulated cat

  12. Mammals of Australia's tropical savannas: a conceptual model of assemblage structure and regulatory factors in the Kimberley region.

    PubMed

    Radford, Ian J; Dickman, Christopher R; Start, Antony N; Palmer, Carol; Carnes, Karin; Everitt, Corrin; Fairman, Richard; Graham, Gordon; Partridge, Thalie; Thomson, Allan

    2014-01-01

    We construct a state-and-transition model for mammals in tropical savannas in northern Australia to synthesize ecological knowledge and understand mammalian declines. We aimed to validate the existence of alternative mammal assemblage states similar to those in arid Australian grasslands, and to speculate on transition triggers. Based on the arid grassland model, we hypothesized that assemblages are partitioned across rainfall gradients and between substrates. We also predicted that assemblages typical of arid regions in boom periods would be prevalent in savannas with higher and more regular rainfall. Data from eight mammal surveys from the Kimberley region, Western Australia (1994 to 2011) were collated. Survey sites were partitioned across rainfall zones and habitats. Data allowed us to identify three assemblage states: State 0:--low numbers of mammals, State II:--dominated by omnivorous rodents and State III:--dominated by rodents and larger marsupials. Unlike arid grasslands, assemblage dominance by insectivorous dasyurids (State I) did not occur in savannas. Mammal assemblages were partitioned across rainfall zones and between substrates as predicted, but-unlike arid regions-were not related strongly to yearly rainfall. Mammal assemblage composition showed high regional stability, probably related to high annual rainfall and predictable wet season resource pulses. As a consequence, we speculate that perpetually booming assemblages in savannas allow top-down control of the ecosystem, with suppression of introduced cats by the dingo, the region's top predator. Under conditions of low or erratic productivity, imposed increasingly by intense fire regimes and introduced herbivore grazing, dingoes may not limit impacts of cats on native mammals. These interacting factors may explain contemporary declines of savanna mammals as well as historical declines in arid Australia. The cat-ecosystem productivity hypothesis raised here differs from the already-articulated cat

  13. Scale Effects between Body Size and Limb Design in Quadrupedal Mammals

    PubMed Central

    Kilbourne, Brandon M.; Hoffman, Louwrens C.

    2013-01-01

    Recently the metabolic cost of swinging the limbs has been found to be much greater than previously thought, raising the possibility that limb rotational inertia influences the energetics of locomotion. Larger mammals have a lower mass-specific cost of transport than smaller mammals. The scaling of the mass-specific cost of transport is partly explained by decreasing stride frequency with increasing body size; however, it is unknown if limb rotational inertia also influences the mass-specific cost of transport. Limb length and inertial properties – limb mass, center of mass (COM) position, moment of inertia, radius of gyration, and natural frequency – were measured in 44 species of terrestrial mammals, spanning eight taxonomic orders. Limb length increases disproportionately with body mass via positive allometry (length ∝ body mass0.40); the positive allometry of limb length may help explain the scaling of the metabolic cost of transport. When scaled against body mass, forelimb inertial properties, apart from mass, scale with positive allometry. Fore- and hindlimb mass scale according to geometric similarity (limb mass ∝ body mass1.0), as do the remaining hindlimb inertial properties. The positive allometry of limb length is largely the result of absolute differences in limb inertial properties between mammalian subgroups. Though likely detrimental to locomotor costs in large mammals, scale effects in limb inertial properties appear to be concomitant with scale effects in sensorimotor control and locomotor ability in terrestrial mammals. Across mammals, the forelimb's potential for angular acceleration scales according to geometric similarity, whereas the hindlimb's potential for angular acceleration scales with positive allometry. PMID:24260117

  14. Brain size is correlated with endangerment status in mammals.

    PubMed

    Abelson, Eric S

    2016-02-24

    Increases in relative encephalization (RE), brain size after controlling for body size, comes at a great metabolic cost and is correlated with a host of cognitive traits, from the ability to count objects to higher rates of innovation. Despite many studies examining the implications and trade-offs accompanying increased RE, the relationship between mammalian extinction risk and RE is unknown. I examine whether mammals with larger levels of RE are more or less likely to be at risk of endangerment than less-encephalized species. I find that extant species with large levels of encephalization are at greater risk of endangerment, with this effect being strongest in species with small body sizes. These results suggest that RE could be a valuable asset in estimating extinction vulnerability. Additionally, these findings suggest that the cost-benefit trade-off of RE is different in large-bodied species when compared with small-bodied species. PMID:26888034

  15. Radiobiological effects of heavy ions and protons. [on cells of mammals, bacteria and viruses

    NASA Technical Reports Server (NTRS)

    Ryzhov, N. I.; Vorozhtsova, S. V.; Krasavin, Y. A.; Mashinskaya, T. Y.; Savchenko, N. Y.; Fedorov, B. S.; Khlaponina, V. F.; Shelegedin, V. N.; Gut, L.; Sabo, L.

    1974-01-01

    Radiobiological effects of heavy ions and protons are studied on cells of mammals, bacteria, viruses and DNA of bacteria. Results show that the dose effect dependence bears an exponential character; the reduction of RBE as LET of particle increases reflects the different character of microdistribution of absorbed energy in biological objects with different levels of biological organization.

  16. Trypanosomes of Australian mammals: A review.

    PubMed

    Thompson, Craig K; Godfrey, Stephanie S; Thompson, R C Andrew

    2014-08-01

    Approximately 306 species of terrestrial and arboreal mammals are known to have inhabited the mainland and coastal islands of Australia at the time of European settlement in 1788. The exotic Trypanosoma lewisi was the first mammalian trypanosome identified in Australia in 1888, while the first native species, Trypanosoma pteropi, was taxonomically described in 1913. Since these discoveries, about 22% of the indigenous mammalian fauna have been examined during the surveillance of trypanosome biodiversity in Australia, including 46 species of marsupials, 9 rodents, 9 bats and both monotremes. Of those mammals examined, trypanosomes have been identified from 28 host species, with eight native species of Trypanosoma taxonomically described. These native trypanosomes include T. pteropi, Trypanosoma thylacis, Trypanosoma hipposideri, Trypanosoma binneyi, Trypanosoma irwini, Trypanosoma copemani, Trypanosoma gilletti and Trypanosoma vegrandis. Exotic trypanosomes have also been identified from the introduced mammalian fauna of Australia, and include T. lewisi, Trypanosoma melophagium, Trypanosoma theileri, Trypanosoma nabiasi and Trypanosoma evansi. Fortunately, T. evansi was eradicated soon after its introduction and did not establish in Australia. Of these exotic trypanosomes, T. lewisi is the sole representative that has been reported from indigenous Australian mammals; morphological forms were recorded from two indigenous species of rodents (Hydromys chrysogaster and Rattus fuscipes). Numerous Australian marsupial species are potentially at risk from the native T. copemani, which may be chronically pathogenic, while marsupials, rodents and monotremes appear at risk from exotic species, including T. lewisi, Trypanosoma cruzi and T. evansi. This comprehensive review of trypanosome biodiversity in Australia highlights the negative impact of these parasites upon their mammalian hosts, as well as the threatening biosecurity concerns. PMID:25161902

  17. Trypanosomes of Australian mammals: A review

    PubMed Central

    Thompson, Craig K.; Godfrey, Stephanie S.; Thompson, R.C. Andrew

    2014-01-01

    Approximately 306 species of terrestrial and arboreal mammals are known to have inhabited the mainland and coastal islands of Australia at the time of European settlement in 1788. The exotic Trypanosoma lewisi was the first mammalian trypanosome identified in Australia in 1888, while the first native species, Trypanosoma pteropi, was taxonomically described in 1913. Since these discoveries, about 22% of the indigenous mammalian fauna have been examined during the surveillance of trypanosome biodiversity in Australia, including 46 species of marsupials, 9 rodents, 9 bats and both monotremes. Of those mammals examined, trypanosomes have been identified from 28 host species, with eight native species of Trypanosoma taxonomically described. These native trypanosomes include T. pteropi, Trypanosoma thylacis, Trypanosoma hipposideri, Trypanosoma binneyi, Trypanosoma irwini, Trypanosoma copemani, Trypanosoma gilletti and Trypanosoma vegrandis. Exotic trypanosomes have also been identified from the introduced mammalian fauna of Australia, and include T. lewisi, Trypanosoma melophagium, Trypanosoma theileri, Trypanosoma nabiasi and Trypanosoma evansi. Fortunately, T. evansi was eradicated soon after its introduction and did not establish in Australia. Of these exotic trypanosomes, T. lewisi is the sole representative that has been reported from indigenous Australian mammals; morphological forms were recorded from two indigenous species of rodents (Hydromys chrysogaster and Rattus fuscipes). Numerous Australian marsupial species are potentially at risk from the native T. copemani, which may be chronically pathogenic, while marsupials, rodents and monotremes appear at risk from exotic species, including T. lewisi, Trypanosoma cruzi and T. evansi. This comprehensive review of trypanosome biodiversity in Australia highlights the negative impact of these parasites upon their mammalian hosts, as well as the threatening biosecurity concerns. PMID:25161902

  18. Control of prolactin secretion in mammals.

    PubMed

    Clemens, J A; Shaar, C J

    1980-06-01

    Evidence describing the neuroendocrine regulation of prolactin secretion in mammals is reviewed, with focus on catecholamines, serotonin, and polypeptides. Dopamine may be a physiological prolactin inhibiting factor (PIF), while norepinephrine and possibly epinephrine regulate prolactin release at the level of the hypothalamus. Serotonin may participate in the regulation of prolactin secretion by stimulating the release of prolactin releasing factor (PRF). The identity of PRF is not known, but two polypeptides--thyrotropin releasing hormone and vasoactive intestinal polypeptide--can act directly on the adenohypophysis to stimulate prolactin release.

  19. Viruses and virus diseases of marine mammals.

    PubMed

    Smith, A W; Skilling, D E

    1979-11-01

    Poxvirus and several serotypes of calicivirus cause recognizable disease in marine mammals. Pox lesions in pinnipeds are raised and proliferative and are seen most frequently after confinement in captivity. In cetaceans, a poxvirus is associated with a much more benign and chronic lesion called a "tattoo." Numerous caliciviruses of differing antigenic types have been isolated from vesicular lesions and aborted fetuses of northern fur seals and California sea lions as well as from clinically normal and orphaned northern elephant seal pups. An adenovirus has been isolated from a sei whale and an enterovirus has been isolated from a gray whale. PMID:230170

  20. Hybridization increases invasive knotweed success

    PubMed Central

    Parepa, Madalin; Fischer, Markus; Krebs, Christine; Bossdorf, Oliver

    2014-01-01

    Hybridization is one of the fundamental mechanisms by which rapid evolution can occur in exotic species. If hybrids show increased vigour, this could significantly contribute to invasion success. Here, we compared the success of the two invasive knotweeds, Fallopia japonica and F. sachalinensis, and their hybrid, F. × bohemica, in competing against experimental communities of native plants. Using plant material from multiple clones of each taxon collected across a latitudinal gradient in Central Europe, we found that knotweed hybrids performed significantly better in competition with a native community and that they more strongly reduced the growth of the native plants. One of the parental species, F. sachalinensis, regenerated significantly less well from rhizomes, and this difference disappeared if activated carbon was added to the substrate, which suggests allelopathic inhibition of F. sachalinensis regeneration by native plants. We found substantial within-taxon variation in competitive success in all knotweed taxa, but variation was generally greatest in the hybrid. Interestingly, there was also significant variation within the genetically uniform F. japonica, possibly reflecting epigenetic differences. Our study shows that invasive knotweed hybrids are indeed more competitive than their parents and that hybridization increased the invasiveness of the exotic knotweed complex. PMID:24665343

  1. Hybridization increases invasive knotweed success.

    PubMed

    Parepa, Madalin; Fischer, Markus; Krebs, Christine; Bossdorf, Oliver

    2014-03-01

    Hybridization is one of the fundamental mechanisms by which rapid evolution can occur in exotic species. If hybrids show increased vigour, this could significantly contribute to invasion success. Here, we compared the success of the two invasive knotweeds, Fallopia japonica and F. sachalinensis, and their hybrid, F. × bohemica, in competing against experimental communities of native plants. Using plant material from multiple clones of each taxon collected across a latitudinal gradient in Central Europe, we found that knotweed hybrids performed significantly better in competition with a native community and that they more strongly reduced the growth of the native plants. One of the parental species, F. sachalinensis, regenerated significantly less well from rhizomes, and this difference disappeared if activated carbon was added to the substrate, which suggests allelopathic inhibition of F. sachalinensis regeneration by native plants. We found substantial within-taxon variation in competitive success in all knotweed taxa, but variation was generally greatest in the hybrid. Interestingly, there was also significant variation within the genetically uniform F. japonica, possibly reflecting epigenetic differences. Our study shows that invasive knotweed hybrids are indeed more competitive than their parents and that hybridization increased the invasiveness of the exotic knotweed complex. PMID:24665343

  2. 76 FR 43267 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-20

    ... USAF's activities are considered military readiness activities. Pursuant to the Marine Mammal... geographical region'' provisions and amended the definition of ``harassment'' as it applies to a ``military... Notice of Proposed IHA and request for 30-day public comment published on January 23, 2006 (71 FR...

  3. 76 FR 330 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-04

    ... ringed seal (75 FR 77476) and a notice of proposed threatened and not warranted status for subspecies and distinct population segments of the bearded seal (75 FR 77496) in the Federal Register. Neither species is... supports a diverse assemblage of marine mammals, including: Bowhead, gray, beluga, killer, minke,...

  4. 77 FR 65059 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-24

    ... FR 49922). That notice described, in detail, ION's proposed activity, the marine mammal species that... Register notice for the proposed IHA (77 FR 49922; August 17, 2012), ION would start its seismic survey... proposed IHA (77 FR 49922; August 17, 2012), ION's in-ice seismic survey would be performed in a...

  5. 78 FR 18965 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-28

    ... on OCS leases in the Chukchi Sea, Alaska, during the 2014 open-water season (78 FR 12542). NMFS... whether to issue an IHA. NMFS refers the reader to the February 22, 2013, Federal Register notice (78 FR... Specified Activities; Taking Marine Mammals Incidental to an Exploration Drilling Program in the Chukchi...

  6. 78 FR 24731 - Taking Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to an...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-26

    ... Proposed IHA, initiating a 30- day public comment period, on February 22, 2013 (78 FR 12542). We then published a notice extending the comment period by 45 days on March 28, 2013 (78 FR 18965). On April 22... Specified Activities; Taking Marine Mammals Incidental to an Exploration Drilling Program in the Chukchi...

  7. 76 FR 4093 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-24

    ... comment periods in the Federal Register on April 19, 2010 (74 FR 20482) for the Beaufort Sea request and May 7, 2010 (74 FR 25730) for the Chukchi Sea request. On May 27, 2010, following the April 20, 2010... Specified Activities; Taking Marine Mammals Incidental to Exploration Drilling Programs in the Chukchi...

  8. 77 FR 12246 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-29

    ... mammals incidental to black abalone (Haliotis cracherodii) research surveys. The first of five IHAs for the specified activities was issued to VanBlaricom on September 23, 2003 (68 FR 57427; October 3, 2003); the most recent of these was issued on January 18, 2008 (73 FR 4841; January 28, 2008),...

  9. 76 FR 34157 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Operation and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-13

    ... mammals, including: The North Atlantic right whale; blue whale; fin whale; sei whale; minke whale... species. Of the species listed here, the North Atlantic right, blue, fin, sei, humpback, and sperm whales... of their rarity in the Massachusetts Bay area (blue whale, sperm whale, harp seal, hooded...

  10. 78 FR 25703 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Fisheries Research

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-02

    ... (off the U.S. west coast), the Eastern Tropical Pacific Research Area, and the Antarctic Research Area (in the Antarctic Scotia Sea). It is possible that marine mammals may interact with fishing gear (e.g... and treaties related to the management of living marine resources in international waters outside...

  11. 78 FR 63396 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Replacement of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... (78 FR 22096, April 12, 2013). In summary, SDOT proposes to replace the Elliott Bay Seawall from South... result in the take of marine mammals. This area includes the proposed construction zone, Elliott Bay, and... frequently referred to in this rulemaking (78 FR 22096, pages 22099-22102). This section also includes...

  12. 77 FR 51773 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-27

    ... on monitoring of marine mammal reactions to rocket launches at Vandenberg Air Force Base. In those... Administration (NOAA), Commerce. ACTION: Notice; proposed incidental harassment authorization; request for... non-target species, if such an alternative action is chosen, during a proposed house mouse...

  13. 77 FR 23463 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Space Vehicle and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-19

    ... Marine Mammals Incidental to Space Vehicle and Missile Launch Operations at Kodiak Launch Complex, Alaska... two species of pinnipeds incidental to space vehicle and missile launch operations at the Kodiak... launch operations at the KLC, were issued on March 22, 2011 (76 FR 16311, March 23, 2011), and remain...

  14. 75 FR 49709 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ..., 2010 (75 FR 27708). That notice described, in detail, Shell's proposed activity, the marine mammal... application, the notice of proposed IHA (75 FR 27708; May 18, 2010) and this document), NMFS determined that... the proposed IHA (75 FR 27708; May 18, 2010), the EA for the issuance of IHAs to Shell and Statoil...

  15. 77 FR 27720 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-11

    ... notice in the Federal Register (76 FR 58473) discussing the effects on marine mammals and making... the proposed IHA (76 FR 58473, September 21, 2011). The activities to be conducted have not changed... should refer to the proposed IHA notice (76 FR 58473, September 21, 2011), the IHA application...

  16. 78 FR 12720 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-25

    ... in Cook Inlet (77 FR 27720). On December 10, 2012, NMFS published a notice in the Federal Register (77 FR 73434) discussing the effects on marine mammals and making preliminary determinations regarding.... In the notice of the proposed IHA (77 FR 73434, December 10, 2012), NMFS described the second area...

  17. 75 FR 49759 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ... FR 32379). That notice described, in detail, Statoil's proposed activity, the marine mammal species... application, the notice of proposed IHA (75 FR 32379; June 8, 2010) and this document), NMFS determined that... in the proposed IHA (75 FR 32379; June 18, 2010), the EA for the issuance of IHAs to Shell...

  18. 78 FR 51147 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-20

    ..., not NMFS. The goals of the workshop, as stated in the Web site of the workshop, were to (1) Review and... mammals in the Chukchi Sea are discussed in the Federal Register (78 FR 35508; June 12, 2013) notice for... in the Federal Register (78 FR 35508; June 12, 2013) notice for the proposed IHA. No changes...

  19. 75 FR 32379 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-08

    ... mammals, readers are encouraged to review NMFS' response to comments on this matter found in 69 FR 74905 (December 14, 2004), 71 FR 43112 (July 31, 2006), 71 FR 50027 (August 24, 2006), and 71 FR 49418 (August 23... of 26 active airguns in 13 clusters. The difference in discharge volume would lead to an...

  20. 78 FR 52135 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-22

    ... AFB, published in the Federal Register on June 4, 2013 (78 FR 33357). During the 30-day public comment... mammal takes was fully explained in the IHA application, the Notice of Proposed IHA (78 FR 33357, June 4..., and those straddling the 200 meter isobath were clipped to remove deep water areas. In...

  1. 78 FR 57368 - Taking and Importing Marine Mammals: Taking Marine Mammals Incidental to Navy Operations of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-18

    ... operations of SURTASS LFA sonar are in effect through August 15, 2017 (77 FR 50290, August 20, 2012) and are... issued on August 15, 2012 (77 FR 51969, August 28, 2012), for the taking of marine mammals incidental to... the north-central Pacific Ocean under the regulations issued on August 15, 2012 (77 FR 50290,...

  2. 76 FR 27308 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Space Vehicle and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-11

    ... vehicle and missile launch operations at the KLC, were issued on March 22, 2011 (76 FR 16311, March 23... Marine Mammals Incidental to Space Vehicle and Missile Launch Operations at Kodiak Launch Complex, Alaska... Kodiak Launch Complex (KLC) in Kodiak, Alaska. DATES: Effective from April 30, 2011, through April...

  3. 75 FR 12734 - Taking and Importing Marine Mammals; Taking Marine Mammals Incidental to Operation of Offshore...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-17

    ... repair and maintenance; and emergency and oil spill response training. Sections 1 and 2 of BP's... occurrence of oil spills. Petroleum development and associated activities in marine waters introduce sound... NMFS, BP requests authorization to take marine mammals incidental to operation of offshore oil and...

  4. 78 FR 28411 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-14

    ... Mexico Inc. (Shell) for an Incidental Harassment Authorization (IHA) to take marine mammals, by... not limited to, migration, breathing, nursing, breeding, feeding, or sheltering . Summary of Request.... For example, at the Guerreo Negro Lagoon in Baja California, Mexico, which is one of the...

  5. Toward a Tree-of-Life for the boas and pythons: multilocus species-level phylogeny with unprecedented taxon sampling.

    PubMed

    Graham Reynolds, R; Niemiller, Matthew L; Revell, Liam J

    2014-02-01

    Snakes in the families Boidae and Pythonidae constitute some of the most spectacular reptiles and comprise an enormous diversity of morphology, behavior, and ecology. While many species of boas and pythons are familiar, taxonomy and evolutionary relationships within these families remain contentious and fluid. A major effort in evolutionary and conservation biology is to assemble a comprehensive Tree-of-Life, or a macro-scale phylogenetic hypothesis, for all known life on Earth. No previously published study has produced a species-level molecular phylogeny for more than 61% of boa species or 65% of python species. Using both novel and previously published sequence data, we have produced a species-level phylogeny for 84.5% of boid species and 82.5% of pythonid species, contextualized within a larger phylogeny of henophidian snakes. We obtained new sequence data for three boid, one pythonid, and two tropidophiid taxa which have never previously been included in a molecular study, in addition to generating novel sequences for seven genes across an additional 12 taxa. We compiled an 11-gene dataset for 127 taxa, consisting of the mitochondrial genes CYTB, 12S, and 16S, and the nuclear genes bdnf, bmp2, c-mos, gpr35, rag1, ntf3, odc, and slc30a1, totaling up to 7561 base pairs per taxon. We analyzed this dataset using both maximum likelihood and Bayesian inference and recovered a well-supported phylogeny for these species. We found significant evidence of discordance between taxonomy and evolutionary relationships in the genera Tropidophis, Morelia, Liasis, and Leiopython, and we found support for elevating two previously suggested boid species. We suggest a revised taxonomy for the boas (13 genera, 58 species) and pythons (8 genera, 40 species), review relationships between our study and the many other molecular phylogenetic studies of henophidian snakes, and present a taxonomic database and alignment which may be easily used and built upon by other researchers.

  6. Blobology: exploring raw genome data for contaminants, symbionts and parasites using taxon-annotated GC-coverage plots.

    PubMed

    Kumar, Sujai; Jones, Martin; Koutsovoulos, Georgios; Clarke, Michael; Blaxter, Mark

    2013-01-01

    Generating the raw data for a de novo genome assembly project for a target eukaryotic species is relatively easy. This democratization of access to large-scale data has allowed many research teams to plan to assemble the genomes of non-model organisms. These new genome targets are very different from the traditional, inbred, laboratory-reared model organisms. They are often small, and cannot be isolated free of their environment - whether ingested food, the surrounding host organism of parasites, or commensal and symbiotic organisms attached to or within the individuals sampled. Preparation of pure DNA originating from a single species can be technically impossible, but assembly of mixed-organism DNA can be difficult, as most genome assemblers perform poorly when faced with multiple genomes in different stoichiometries. This class of problem is common in metagenomic datasets that deliberately try to capture all the genomes present in an environment, but replicon assembly is not often the goal of such programs. Here we present an approach to extracting, from mixed DNA sequence data, subsets that correspond to single species' genomes and thus improving genome assembly. We use both numerical (proportion of GC bases and read coverage) and biological (best-matching sequence in annotated databases) indicators to aid partitioning of draft assembly contigs, and the reads that contribute to those contigs, into distinct bins that can then be subjected to rigorous, optimized assembly, through the use of taxon-annotated GC-coverage plots (TAGC plots). We also present Blobsplorer, a tool that aids exploration and selection of subsets from TAGC-annotated data. Partitioning the data in this way can rescue poorly assembled genomes, and reveal unexpected symbionts and commensals in eukaryotic genome projects. The TAGC plot pipeline script is available from https://github.com/blaxterlab/blobology, and the Blobsplorer tool from https://github.com/mojones/Blobsplorer.

  7. Does leptin signal adiposity in the egg-laying mammal, Tachyglossus aculeatus?

    PubMed

    Sprent, Jenny; Jones, Susan M; Nicol, Stewart C

    2012-09-01

    Leptin is a peptide hormone best known for its role in feedback regulation of adiposity in eutherian mammals. Normally an increase in adipose tissue mass leads to an increase in circulating leptin which increases energy expenditure and limits food intake, but in hibernating eutherian mammals this relationship may change to allow prehibernatory fattening. The echidna (Tachyglossus aculeatus) is a monotreme mammal which accumulates significant fat reserves before entering hibernation, and mates immediately at the end of hibernation. We hypothesised that echidnas would show a strong relationship between body mass and plasma leptin for most of the year which would change during the pre-hibernatory period. We measured plasma leptin and body mass in free-ranging echidnas over several reproductive and hibernation cycles. There were significant seasonal variations in plasma leptin in both sexes, with the highest levels occurring in hibernation and in mating females. The lowest levels were found in males when they were foraging maximally after the reproductive period. We used mass%, body mass at the time of sampling as a percentage of long term mean mass, as a proxy for adiposity. There was a weak negative relationship between mass% and plasma leptin, from which we infer a weak negative relationship between adiposity and plasma leptin as has been found in reptiles and birds, rather than the strong positive relationship found in other mammals. PMID:22750512

  8. Small mammals and forest fuel reduction: national-scale responses to fire and fire surrogates.

    PubMed

    Converse, Sarah J; White, Gary C; Farris, Kerry L; Zack, Steve

    2006-10-01

    Forest fuel reduction treatments are increasingly used by managers to reduce the risk of high-severity wildfire and to manage changes in the ecological function of forests. However, comparative ecological effects of the various types of treatments are poorly understood. We examined short-term patterns in small-mammal responses to mechanical thinning, prescribed-fire, and mechanical thinning/prescribed-fire combination treatments at eight different study areas across the United States as a part of the National Fire and Fire Surrogate (FFS) Project. Research questions included: (1) do treatments differ in their effect on small mammal densities and biomass? and (2) are effects of treatments consistent across study areas? We modeled taxa-specific densities and total small-mammal biomass as functions of treatment types and study area effects and ranked models based on an information-theoretic model selection criterion. Small-mammal taxa examined, including deer mice (Peromyscus maniculatus), yellow-pine chipmunks (Tamias amoenus), and golden-mantled ground squirrels (Spermophilus lateralis), as well as all Peromyscus and Tamias species, had top-ranked models with responses varying both by treatment type and study area. In each of these cases, the top-ranked model carried between 69% and 99% of the total weight in the model set, indicating strong support for the top-ranked models. However, the top-ranked model of total small-mammal biomass was a model with biomass varying only with treatment (i.e., treated vs. untreated), not by treatment type or study area; again, this model had strong support, with 75% of the total model weight. Individual species and taxa appear to have variable responses to fuel reduction treatment types in different areas; however, total small-mammal biomass appears generally to increase after any type of fuel reduction. These results suggest that there is substantial variability in taxa-specific responses to treatments and indicate that adaptive

  9. Small mammal tooth enamel carbon isotope record of C4 grasses in late Neogene China

    NASA Astrophysics Data System (ADS)

    Arppe, Laura; Kaakinen, Anu; Passey, Benjamin H.; Zhang, Zhaoqun; Fortelius, Mikael

    2015-10-01

    The spatiotemporal pattern of the late Cenozoic spread of C4 vegetation is an important indicator of environmental change that is intertwined with the uplift of the Himalaya and Tibetan Plateau, and the development of the East Asian monsoons. To explore the spread of C4 vegetation in China and shed new light on regional climatic evolution, we measured δ13C values of more than 200 small mammal teeth (primarily rodents and lagomorphs) using a laser ablation isotope ratio mass spectrometry approach. Small mammals are highly sensitive indicators of their environment because they have limited spatial ranges and because they have minimal time-averaging of carbon isotope signatures of dietary components. The specimens originate from four classic Late Miocene fossil localities, Lufeng, Yuanmou, Lingtai, and Ertemte, along a southwest-northeast transect from Yunnan Province to Inner Mongolia. In Yunnan (Lufeng, Yuanmou) and on the Loess Plateau (Lingtai), the small mammal δ13C values record nearly pure C3 ecosystems, and mixed but C3-based ecosystems, respectively, in agreement with previous studies based on carbon isotopes of large herbivores and soil carbonates. In Inner Mongolia, the micromammalian tooth enamel δ13C record picks up the presence of C4 vegetation where large mammal samples do not, indicating a mixed yet C3-dominated ecosystem at ~ 6 Ma. As a whole, the results support a scenario of northward increasing C4 grass abundance in a pattern that mirrors northward decreasing precipitation of the summer monsoon system. The results highlight differences between large and small mammals as indicators of C4 vegetation in ancient ecosystems, particularly the ability of small mammal δ13C values to detect the presence of minor components of the vegetation structure.

  10. Behavioral Ecology of Captive Species: Using Bibliographic Information to Assess Pet Suitability of Mammal Species

    PubMed Central

    Koene, Paul; de Mol, Rudi M.; Ipema, Bert

    2016-01-01

    Which mammal species are suitable to be kept as pet? For answering this question many factors have to be considered. Animals have many adaptations to their natural environment in which they have evolved that may cause adaptation problems and/or risks in captivity. Problems may be visible in behavior, welfare, health, and/or human–animal interaction, resulting, for example, in stereotypies, disease, and fear. A framework is developed in which bibliographic information of mammal species from the wild and captive environment is collected and assessed by three teams of animal scientists. Oneliners from literature about behavioral ecology, health, and welfare and human–animal relationship of 90 mammal species are collected by team 1 in a database and strength of behavioral needs and risks is assessed by team 2. Based on summaries of those strengths the suitability of the mammal species is assessed by team 3. Involvement of stakeholders for supplying bibliographic information and assessments was propagated. Combining the individual and subjective assessments of the scientists using statistical methods makes the final assessment of a rank order of suitability as pet of those species less biased and more objective. The framework is dynamic and produces an initial rank ordered list of the pet suitability of 90 mammal species, methods to add new mammal species to the list or remove animals from the list and a method to incorporate stakeholder assessments. A model is developed that allows for provisional classification of pet suitability. Periodical update of the pet suitability framework is expected to produce an updated list with increased reliability and accuracy. Furthermore, the framework could be further developed to assess the pet suitability of additional species of other animal groups, e.g., birds, reptiles, and amphibians. PMID:27243023

  11. Behavioral Ecology of Captive Species: Using Bibliographic Information to Assess Pet Suitability of Mammal Species.

    PubMed

    Koene, Paul; de Mol, Rudi M; Ipema, Bert

    2016-01-01

    Which mammal species are suitable to be kept as pet? For answering this question many factors have to be considered. Animals have many adaptations to their natural environment in which they have evolved that may cause adaptation problems and/or risks in captivity. Problems may be visible in behavior, welfare, health, and/or human-animal interaction, resulting, for example, in stereotypies, disease, and fear. A framework is developed in which bibliographic information of mammal species from the wild and captive environment is collected and assessed by three teams of animal scientists. Oneliners from literature about behavioral ecology, health, and welfare and human-animal relationship of 90 mammal species are collected by team 1 in a database and strength of behavioral needs and risks is assessed by team 2. Based on summaries of those strengths the suitability of the mammal species is assessed by team 3. Involvement of stakeholders for supplying bibliographic information and assessments was propagated. Combining the individual and subjective assessments of the scientists using statistical methods makes the final assessment of a rank order of suitability as pet of those species less biased and more objective. The framework is dynamic and produces an initial rank ordered list of the pet suitability of 90 mammal species, methods to add new mammal species to the list or remove animals from the list and a method to incorporate stakeholder assessments. A model is developed that allows for provisional classification of pet suitability. Periodical update of the pet suitability framework is expected to produce an updated list with increased reliability and accuracy. Furthermore, the framework could be further developed to assess the pet suitability of additional species of other animal groups, e.g., birds, reptiles, and amphibians. PMID:27243023

  12. Spatial and temporal exposure patterns in non-target small mammals during brodifacoum rat control.

    PubMed

    Geduhn, Anke; Esther, Alexandra; Schenke, Detlef; Mattes, Hermann; Jacob, Jens

    2014-10-15

    Worldwide pest rodents on livestock farms are often regulated using anticoagulant rodenticides (ARs). Second generation ARs in particular can cause poisoning in non-target species due to their high toxicity and persistence. However, research on exposure of small mammals is rare. We systematically investigated spatial and temporal exposure patterns of non-target small mammals in a large-scale replicated study. Small mammals were trapped at different distances to bait stations on ten farms before, during and after brodifacoum (BR) bait application, and liver samples of 1178 non-target small mammals were analyzed for residues of eight ARs using liquid chromatography coupled with tandem mass spectrometry. BR residues were present in 23% out of 742 samples collected during and after baiting. We found clear spatial and temporal exposure patterns. High BR residue concentrations mainly occurred within 15m from bait stations. Occurrence and concentrations of residues significantly decreased with increasing distance. This pattern was found in almost all investigated taxa. After baiting, significantly more individuals contained residues than during baiting but concentrations were considerably lower. Residue occurrence and concentrations differed significantly among taxa, with the highest maximal residue concentrations in Apodemus species, which are protected in Germany. Although Sorex species are known to be insectivorous we regularly found residues in this genus. Residues of active agents other than brodifacoum were rare in all samples. The confirmation of substantial primary exposure in non-target small mammals close to the baiting area indicates considerable risk of secondary poisoning of predators, a pathway that was possibly underestimated until now. Our results will help to develop risk mitigation strategies to reduce risk for non-target small mammals, as well as their predators, in relation to biocidal AR usage.

  13. Paracoccidioides brasiliensis Infection in Small Wild Mammals.

    PubMed

    Sbeghen, Mônica Raquel; Zanata, Thais Bastos; Macagnan, Rafaela; de Abreu, Kaue Cachuba; da Cunha, Willian Luiz; Watanabe, Maria Angelica Ehara; de Camargo, Zoilo Pires; Ono, Mario Augusto

    2015-12-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis prevalent in Brazil and other Latin American countries. The etiological agents of PCM are the thermo-dimorphic fungi Paracoccidioides brasiliensis and P. lutzii. Taking into account that the natural habitat of Paracoccidioides spp. is still undefined, domestic and wild animals could be useful as indicators of Paracoccidioides spp. presence in endemic areas. The objective of this study was to evaluate the infection of small wild mammals by P. brasiliensis in an endemic area for human PCM. Samples from 38 wild mammals from different species such as Akodon sp., Thaptomys nigrita, Euryoryzomys russatus, Oligoryzomys nigripes, Monodelphis sp., Sooretamys angouya, Abrawayaomys angouya, Abrawayaomys ruschii and Akodontinae sp. were evaluated by ELISA, immunodiffusion, histopathology, nested PCR and culture. The overall positivity to gp43 observed in the ELISA was 23.7%. Samples from heart and liver of one O. nigripes were PCR positive, and the animal was also seropositive to gp43 in ELISA. This study showed that wild animals living in endemic areas for PCM are infected with P. brasiliensis and can be valuable epidemiological markers of the fungus presence in the environment. This is the first evidence of PCM infection in Akodon sp., E. russatus, T. nigrita and O. nigripes. PMID:26232125

  14. Biogeography of time partitioning in mammals

    PubMed Central

    Bennie, Jonathan J.; Duffy, James P.; Inger, Richard; Gaston, Kevin J.

    2014-01-01

    Many animals regulate their activity over a 24-h sleep–wake cycle, concentrating their peak periods of activity to coincide with the hours of daylight, darkness, or twilight, or using different periods of light and darkness in more complex ways. These behavioral differences, which are in themselves functional traits, are associated with suites of physiological and morphological adaptations with implications for the ecological roles of species. The biogeography of diel time partitioning is, however, poorly understood. Here, we document basic biogeographic patterns of time partitioning by mammals and ecologically relevant large-scale patterns of natural variation in “illuminated activity time” constrained by temperature, and we determine how well the first of these are predicted by the second. Although the majority of mammals are nocturnal, the distributions of diurnal and crepuscular species richness are strongly associated with the availability of biologically useful daylight and twilight, respectively. Cathemerality is associated with relatively long hours of daylight and twilight in the northern Holarctic region, whereas the proportion of nocturnal species is highest in arid regions and lowest at extreme high altitudes. Although thermal constraints on activity have been identified as key to the distributions of organisms, constraints due to functional adaptation to the light environment are less well studied. Global patterns in diversity are constrained by the availability of the temporal niche; disruption of these constraints by the spread of artificial lighting and anthropogenic climate change, and the potential effects on time partitioning, are likely to be critical influences on species’ future distributions. PMID:25225371

  15. Circannual Testis Changes in Seasonally Breeding Mammals.

    PubMed

    Jiménez, Rafael; Burgos, Miguel; Barrionuevo, Francisco J

    2015-01-01

    In the non-equatorial zones of the Earth, species concentrate their reproductive effort in the more favorable season. A consequence of seasonal breeding is seasonal testis regression, which implies the depletion of the germinative epithelium, permeation of the blood-testis barrier, and reduced androgenic function. This process has been studied in a number of vertebrates, but the mechanisms controlling it are not yet well understood. Apoptosis was assumed for years to be an important effector of seasonal germ cell depletion in all vertebrates, including mammals, but an alternative mechanism has recently been reported in the Iberian mole as well as in the large hairy armadillo. It is based on the desquamation of meiotic and post-meiotic germ cells as a consequence of altered Sertoli-germ cell adhesion molecule expression and distribution. Desquamated cells are either discarded alive through the epididymis, as in the mole, or subsequently die by apoptosis, as in the armadillo. Also, recent findings on the reproductive cycle of the greater white-toothed shrew at the meridional limits of its distribution area have revealed that the mechanisms controlling seasonal breeding are in fact far more plastic and versatile than initially suspected. Perhaps these higher adaptive capacities place mammals in a better position to face the ongoing climate change. PMID:26375035

  16. Placentation in mammals once grouped as insectivores.

    PubMed

    Carter, Anthony M; Enders, Allen C

    2010-01-01

    Interest in insectivoran grade mammals has been reawakened by taxonomic changes that place tenrecs and golden moles in a new order and separate hedgehogs from moles, shrews and solenodons. This survey of their placentation shows there is great variation even within families. As an example three subfamilies of tenrec have been examined. The interhemal region is cellular hemomonochorial in Echinops and Microgale but endotheliochorial in Micropotamogale. Golden moles, which are placed in the same order, have hemodichorial placentation. Many insectivores have complex arrangements for histotrophic nutrition involving columnar trophoblast cells. These range from areolae in moles through complexly folded hemophagous regions in tenrecs to the trophoblastic annulus in shrews. Of these placental characters, few offer support to current phylogenies. However, the case for placing hedgehogs and gymnures in a separate order (Erinaceomorpha) is bolstered by the presence of interstitial implantation, amniogenesis by cavitation, a hemochorial barrier and a prominent spongy zone; these features do not occur in shrews, moles or solenodons (Soricomorpha). Three insectivoran grade mammals deserve close attention as they have been selected for genome sequencing. One of these, the European hedgehog (Erinaceus europaeus), has not been studied with current methodology and renewed investigation of this or the closely related genus Atelerix should be a priority.

  17. The specification of imprints in mammals.

    PubMed

    Hanna, C W; Kelsey, G

    2014-08-01

    At the heart of genomic imprinting in mammals are imprinting control regions (ICRs), which are the discrete genetic elements that confer imprinted monoallelic expression to several genes in imprinted gene clusters. A characteristic of the known ICRs is that they acquire different epigenetic states, exemplified by differences in DNA methylation, in the sperm and egg, and these imprint marks remain on the sperm- and oocyte-derived alleles into the next generation as a lifelong memory of parental origin. Although there has been much focus on gametic marking of ICRs as the point of imprint specification, recent mechanistic studies and genome-wide DNA methylation profiling do not support the existence of a specific imprinting machinery in germ cells. Rather, ICRs are part of more widespread methylation events that occur during gametogenesis. Instead, a decisive component in the specification of imprints is the choice of which sites of gamete-derived methylation to maintain in the zygote and preimplantation embryo at a time when much of the remainder of the genome is being demethylated. Among the factors involved in this selection, the zinc-finger protein Zfp57 can be regarded as an imprint-specific, sequence-specific DNA binding factor responsible for maintaining methylation at most ICRs. The recent insights into the balance of gametic and zygotic contributions to imprint specification should help understand mechanistic opportunities and constraints on the evolution of imprinting in mammals.

  18. Earliest known Australian Tertiary mammal fauna

    NASA Astrophysics Data System (ADS)

    Godthelp, Henk; Archer, Michael; Cifelli, Richard; Hand, Suzanne J.; Gilkeson, Coral F.

    1992-04-01

    REMAINS of Early Eocene vertebrates from freshwater clays near Murgon, southeastern Queensland, represent Australia's oldest marsupials, bats, non-volant placentals, frogs, madtsoiid snakes, trionychid turtles1and birds. Radiometric dating of illites forming part of the matrix of the mammal-bearing zone has given a minimum age estimate of 54.6 +/- 0.05 x 106 years, which is roughly twice as old as any marsupials previously known from Australia2 and well before the 38 million year (Myr) separation of Australia from Antarctica/South America3. All marsupials so far known from the Tingamarra Local Fauna are more derived (being dilambdodont) than peradectids. None of them is clearly a member of a previously known Australian family, but some could be uniquely plesiomorphic dasyuroids or perameloids. Another is autapomorphically specialized and indicative of at least partial isolation of the Australian portion of Gondwana. Here we report on the discovery of a tooth of the earliest non-volant placental known from Australia, Tingamarra porterorum gen.et sp. nov., which seems to be a condylarth-like placental mammal. The presence of non-volant placentals in the Early Tertiary of Australia challenges a common presumption that marsupials dominated Australia's therian assemblages because of failure of such placentals to reach Australia before the Late Tertiary.

  19. Intraperitoneal insemination in mammals: a review.

    PubMed

    Yaniz, J L; Lopez-Bejar, M; Santolaria, P; Rutllant, J; Lopez-Gatius, F

    2002-04-01

    This review focuses on factors associated with the development of intraperitoneal insemination in mammals. Findings to date indicate that fertility improves as the sperm cell concentration rises, but that the optimal sperm number differs in each species. Sperm washing before intraperitoneal insemination favours fertility. Peritoneal fluid shows a variable effect on spermatozoa, depending on the hormonal status of the female. The optimal time for insemination appears to be just prior to ovulation. The technique may be performed either through the abdominal or the vaginal wall. Verification of sperm deposition in the proximity of the ovaries improves fertility rates. Although associated with some risk of infection and an immune reaction against spermatozoa, the intraperitoneal technique rarely gives rise to severe anaphylactic shock, peritonitis, adhesion formation and the production of anti-sperm antibodies and these complications may be prevented by adequate sperm pretreatment and antibiotic therapy. The success of intraperitoneal insemination in humans, with results comparable with those of intrauterine insemination in the treatment of infertility, suggest the potential use of this technique in domestic mammals, especially in those in which intrauterine insemination poses practical difficulties. Some of the methods applied in human intraperitoneal insemination, such as confirming the position of the needle in the peritoneal cavity, and sperm pre-treatments might also improve results in domestic species. Conversely, the use of the animal model should help to develop some aspects of this technique in humans. PMID:11975743

  20. Paracoccidioides brasiliensis Infection in Small Wild Mammals.

    PubMed

    Sbeghen, Mônica Raquel; Zanata, Thais Bastos; Macagnan, Rafaela; de Abreu, Kaue Cachuba; da Cunha, Willian Luiz; Watanabe, Maria Angelica Ehara; de Camargo, Zoilo Pires; Ono, Mario Augusto

    2015-12-01

    Paracoccidioidomycosis (PCM) is a systemic mycosis prevalent in Brazil and other Latin American countries. The etiological agents of PCM are the thermo-dimorphic fungi Paracoccidioides brasiliensis and P. lutzii. Taking into account that the natural habitat of Paracoccidioides spp. is still undefined, domestic and wild animals could be useful as indicators of Paracoccidioides spp. presence in endemic areas. The objective of this study was to evaluate the infection of small wild mammals by P. brasiliensis in an endemic area for human PCM. Samples from 38 wild mammals from different species such as Akodon sp., Thaptomys nigrita, Euryoryzomys russatus, Oligoryzomys nigripes, Monodelphis sp., Sooretamys angouya, Abrawayaomys angouya, Abrawayaomys ruschii and Akodontinae sp. were evaluated by ELISA, immunodiffusion, histopathology, nested PCR and culture. The overall positivity to gp43 observed in the ELISA was 23.7%. Samples from heart and liver of one O. nigripes were PCR positive, and the animal was also seropositive to gp43 in ELISA. This study showed that wild animals living in endemic areas for PCM are infected with P. brasiliensis and can be valuable epidemiological markers of the fungus presence in the environment. This is the first evidence of PCM infection in Akodon sp., E. russatus, T. nigrita and O. nigripes.