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The North Pacific Coast (NPC) of North America is a region of high mammalian endemism, possibly due to its highly fragmented landscape and complex glacial history. For example, four island and one mainland subspecies of ermine, Mustela erminea, have been described as endemic to southeast Alaska alone. To better understand the role of past climatic change in generating diversity in the region, we examined DNA sequence variation in the mitochondrial cytochrome b gene of 210 ermine from across North America, with an emphasis on Alaska and British Columbia. We found three distinct (1.5-3.6% uncorrected 'p') lineages of ermine, all of which occur in southeast Alaska. One lineage includes a southeast Alaska endemic and specimens from Alaska (outside of southeast) and Eurasia. A second lineage includes two southeast Alaskan endemics and ermine from western Canada and the coterminous United States. The close relationships of these purported endemics to ermine outside of southeast Alaska suggest that they colonized the region from Beringian and southern glacial refugia, respectively, following deglaciation of the NPC. The third lineage appears restricted to the Prince of Wales Island complex in southeast Alaska (two subspecies) and Graham Island (Haida Gwaii), British Columbia. This restricted distribution suggests that these populations may be derived from relicts that persisted in a coastal refugium during the Wisconsin glaciation. Studies of nuclear genes and adaptive morphological evolution are necessary to further explore discrepancies between the geographical pattern of differentiation based on mtDNA and the existing subspecific taxonomy based on morphology. 相似文献
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Tracy E. Popowics 《Journal of morphology》1998,237(1):69-90
This study describes dental development within the ferret, Mustela putorius, through study of the form of the carnassial teeth and the upper first molar at progressive growth stages. Primordial teeth were serially sectioned in sagittal and transverse planes and three-dimensional reconstructions of tooth primordia were generated using MacReco software. Regional growth of the crown and asynchronous maturation of the dental tissues were observed in each tooth. The upper carnassial blade develops early and the tooth increases in length rapidly. Lingual growth of the upper carnassial is less pronounced and the protocone and its surrounding region mature late. The lower carnassial blade develops early and the talonid is late to mature. Development of the upper first molar differs from carnassial development in the early emphasis upon transverse growth and reduced lengthwise expansion. The early development of the carnassial blades in the ferret is shared with other carnivores, and may reflect the functional significance of this feature. Later stages of tooth ontogeny differ among carnivoran taxa and the specialized morphology of ferret teeth results from an apparently truncated period of late tooth ontogeny. This suggests that carnivoran species may share a common path of early development that specifies the ontogeny of homologous tooth features and that in later stages developmental differences result in species-specific tooth forms. J. Morphol. 237:69–90, 1998. © 1998 Wiley-Liss, Inc. 相似文献
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Assessment of locomotor modes in fossil taxa must often be made on the basis of heavily fragmented postcranial material. Previous authors have used quantitative methods to determine locomotor function from whole postcranial elements. The goals of this project were to assess the ability of element shape to discern between locomotor modes through landmark analysis, and to apply the results to assessment of fossils. Results suggest that element shape is a good predictor of function, but that different elements have different predictive capacities for each locomotor mode. Additionally, a relationship between size and shape exists that appears to drive morphological differentiation in the group. Finally, data from the extant sample were applied to fossil material of the extinct Plio-Pleistocene taxon Trigonictis . The results suggest that the locomotor mode of Trigonictis was generalized and probably an intermediate between the half-bound locomotion found in weasels and ferrets and the scansorial locomotion of martens and fishers. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 895–914. 相似文献
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Paleontological and molecular data suggest that the divergence of the European and Asian badgers (Meles meles and Meles leucurus, respectively) from their ancestor Meles thorali might have taken place in the Middle to Late Villafranchian boundary (ca. 1.8 Ma). However, the available record of Late Villafrachian European badgers is scanty and poorly known, and this hypothesis needs more paleontological data in order to be tested. The badger hemimandible from the Iberian locality of Fuente Nueva 3, a locality placed in the beginning of the Late Villafranchian, supports the idea of an early divergence between European and Asian badgers. 相似文献
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Cristine Silveira Trinca Camila Fernandes Jaeger Eduardo Eizirik 《Biological journal of the Linnean Society. Linnean Society of London》2013,109(4):932-948
Non‐invasive genetic analysis has been frequently employed to estimate ecological and population parameters for many secretive and/or threatened species. However, Neotropical carnivores have so far been scarcely targeted by such studies. The Neotropical otter (Lontra longicaudis) is a poorly‐known species for which local levels of genetic diversity and demographic parameters are virtually absent. We employed non‐invasive sampling and amplification of microsatellite loci to investigate population size and density, spatial organization, and relatedness of a wild Neotropical otter population in an Atlantic forest area in southern Brazil. We directly identified 28 individuals and estimate a rather high population density at the study site. Spatial organization analysis indicated that male cumulative displacement was higher than that of females, with the latter sex showing evidence of philopatric behaviour. Also, the reconstruction of genealogical relationships suggests that spatial organization in this otter appears to be influenced by relatedness. By allowing the testing of specific hypothesis targeting these issues, our results provided important glimpses into the Neotropical otter's population biology. Moreover, the findings of the present study reaffirm the power of non‐invasive genetics to investigate the biology of this elusive species, and open up new avenues for ecological and demographic studies of other Neotropical carnivores. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 932–948. 相似文献
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记述了云南禄丰古猿产地的一些獾类化石,主要据其牙齿和下颌特征订为食肉目、鼬科、獾亚科中一个新的属种——禄丰云南獾(Yunnanotherium lufengense gen.et sp.nov.)。从M1的冠面和牙根的特征看,可把宗冠福1991年提出、1997年所订的Trochotherium yuanmouense 1)的1枚M1(另1枚所谓m2经本文作者鉴定不属于这类动物)以及在元谋雷老发现的1枚M1和1枚m2放入这个属中。另外,产自禄丰古猿产地D剖面6层的1枚单个的m1也可归入这个属中。云南獾与欧洲的Trochotherium在牙齿(主要是M1)方面有某种程度的相像(如冠面较平坦、齿尖较低、齿根多),都是一类主要以软体动物为生的食肉动物,但二者之间在牙齿(特别是M1)的结构和下颌形态方面仍有明显的区别。这可能与二者所生长的时代以及生态环境不同有关。 相似文献
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The Javan ferret-badger Melogale orientalis (Carnivora: Mustelidae: Helictidinae) is a small carnivore endemic to Indonesia. In the family Mustelidae, 10 Eimeria, 12 Cystoisopora, one Isospora, and one Hammondia species are known, but no eimeriid coccidia has been yet described in the subfamily Helictinidae (ferret badgers). Coproscopic examination of Javan ferret-badgers imported into the Czech Republic revealed the presence of coccidian oocysts. Sporulated oocysts differ from other Eimeria known in the family Mustelidae by their small size (12.4–16.1 × 10.4–13.4 μm) and ovoidal shape. Morphological data and phylogenetic analyses of 18S rRNA and COI genes indicated a new species of Eimeria found in faecal samples of Javan ferret badgers. The species is described as E. melogale n. sp. 相似文献
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