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41.
Wolverines (Gulo gulo) are found in low densities throughout their circumpolar distribution. They are also potentially susceptible to human-caused population fragmentation (development, recreation and fur harvesting). The combination of these factors has contributed to this species being listed as having either vulnerable or endangered status across much of its current range. The effects of inherently low densities and anthropogenic pressures on the genetic structure and variation of wolverine populations are, as yet, unknown. In this study, 461 individuals were typed at 12 microsatellite loci to investigate the population genetic structure of wolverines from north-western Alaska to eastern Manitoba. Levels of gene flow and population differentiation among the sampled regions were estimated via a genotype assignment test, pairwise F(ST), and two genetic distance measures. Our results suggest that wolverine populations from southernmost regions, in which anthropogenic factors are strongest, revealed more genetic structuring than did northern populations. Furthermore, these results suggest that reductions in this species' range may have led to population fragmentation in the extreme reaches of its southern distribution. The continued reduction of suitable habitat for this species may lead to more populations becoming isolated remnants of a larger distribution of northern wolverines, as documented in other North American carnivore species. 相似文献
42.
YSTEIN WIIG 《Zoological Journal of the Linnean Society》1989,95(3):177-204
Craniometric variation in Norwegian wolverines was analysed using univariate and multivariate techniques. The wolverine skull seems to be full-grown after about 9 months in both sexes although some dimensions continued to grow at a slow rate after the first year. Size allometry was studied in skulls older than 11 months. Allometric coefficients were calculated from different methods. The multivariate allometric coefficients were found to reflect the same allometric patterns as were found from the reduced major axis and from the direction cosines of PCI, whereas the coefficients seem to be underestimated by the least-square regression method. Sexual dimorphism was found to be highly significant, males being the larger sex. The female skulls were found to be relatively broader and to have a relatively higher coronoid process than the male skulls. It seems that the females have a relatively stronger feeding apparatus than the males, which leads to less absolute differences in strength, as reflected in a very high degree of dietary overlap. Two discriminant functions were calculated which both classified the material into their correct sex with nearly 100% accuracy. Geographical variation between samples from Nordland and Finnmark counties were studied. No significant multivariate variation was found between the female skulls. The male variation was highly significant; the Nordland skulls seem to have longer carnassials than those from Finnmark. 相似文献
43.
H. L. DUGDALE P. NOUVELLET L. C. POPE T. BURKE D. W. MACDONALD 《Journal of evolutionary biology》2010,23(2):282-292
Age at first (α) and last (ω) breeding are important life‐history traits; however, the direction and strength of selection detected on traits may vary depending on the fitness measure used. We provide the first estimates of lifetime breeding success (LBS) and λind (the population growth rate of an individual) of European badgers Meles meles, by genotyping 915 individuals, sampled over 18 years, for 22 microsatellites. Males are slightly larger than females, and the opportunity for selection was slightly greater for males, as predicted. λind and LBS both performed well in predicting the number of grand‐offspring, and both detected selection for a late ω, until the age of eight. Differential selection (S′α) for an early α, however, was only detected using LBS, not with λind. In declining populations (λind < 1) selection favours reproduction later in life, whereas early reproduction is selected in increasing populations (λind > 1). As 41% of badgers were assigned only one offspring (λind < 1), whereas 40% were assigned more than two (λind > 1), this cancelled out S′α measured by λind. 相似文献
44.
45.
Manuela Aiglstorfer Elmar P.J. Heizmann Stphane Peign 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2019,52(3):429-444
The fossil remains of the moschid Micromeryx flourensianus from the Sansan type locality (middle Miocene, France) show indications of fluvial transport and clear signs of carnivore activity. Most remarkable are bite marks with a distinctive pattern on the heels of the moschids (marks predominantly on the medial side of the astragalus and on the lateral side of the calcaneus). These allow the reconstruction of a specific hunting behaviour: most likely, the predator was attacking the moschid prey by deliberate bites on the heel during the chase, probably to immobilize it. This kind of behaviour is recorded for mustelids hunting moschids in modern ecosystems. Considering this and evaluating the size and pattern of the bite marks, it was possible to name the mustelids Martes sansaniensis, Taxodon sansaniensis and Proputorius sansaniensis as the most likely candidates for the hunt on Micromeryx. This offers an insight into a predator–prey relationship in the fossil‐rich locality Sansan and reveals that a hunting behaviour present in modern mustelids might actually represent a trait at least 14 million years old. 相似文献
46.
ØYSTEIN WIIG F.L.S. 《Zoological Journal of the Linnean Society》1998,95(3):177-204
Craniometric variation in Norwegian wolverines was analysed using univariate and multivariate techniques. The wolverine skull seems to be full-grown after about 9 months in both sexes although some dimensions continued to grow at a slow rate after the first year. Size allometry was studied in skulls older than 11 months. Allometric coefficients were calculated from different methods. The multivariate allometric coefficients were found to reflect the same allometric patterns as were found from the reduced major axis and from the direction cosines of PCI, whereas the coefficients seem to be underestimated by the least-square regression method. Sexual dimorphism was found to be highly significant, males being the larger sex. The female skulls were found to be relatively broader and to have a relatively higher coronoid process than the male skulls. It seems that the females have a relatively stronger feeding apparatus than the males, which leads to less absolute differences in strength, as reflected in a very high degree of dietary overlap. Two discriminant functions were calculated which both classified the material into their correct sex with nearly 100% accuracy. Geographical variation between samples from Nordland and Finnmark counties were studied. No significant multivariate variation was found between the female skulls. The male variation was highly significant; the Nordland skulls seem to have longer carnassials than those from Finnmark. 相似文献
47.
Resource partitioning among British and Irish mustelids 总被引:5,自引:0,他引:5
Robbie A. McDonald 《The Journal of animal ecology》2002,71(2):185-200
48.
Max Kasparek 《Zoology in the Middle East.》2013,59(1):8-11
Abstract It was shown that the Weasel is distributed over the whole of Anatolia The species’ considerable size, the occasional occurrence of a white winter coat and the existence of two types of Weasels (nivalis type and minuta type) in Turkey have often lead to the wrong assumption that the Stoat (M. erminea) also occurs in Turkey. 相似文献
49.
Jerry W. Dragoo Robert D. Bradley Rodney L. Honeycutt Joe W. Templeton 《Journal of Mammalian Evolution》1993,1(4):255-267
Phylogenetic relationships among the three recognized genera of skunks (Mephitis, Spilogale, andConepatus) were examined using allozymes and nucleotide sequence data from portions of the cytochromeb gene and displacement loop of the mitochondrial genome. The data sets indicated thatMephitis andSpilogale shared a common ancestor after they diverged fromConepatus. Intrageneric relationships revealed that the level of genetic divergence between the two species ofSpilogale was equal to the level of divergence between the two species ofMephitis, with the two North American species ofConepatus possessing the least amount of genetic divergence. 相似文献
50.
This paper reports a new species of ancient badger – Meles iberica n. sp. – discovered at the Fonelas P-1 Plio-Pleistocene site (Cuenca de Guadix, Granada, Spain). The anatomical features of its fossils, which identify it as a new species of Meles, include: the great robustness and small size of the specimens found, orbits nearly closed by well-developed zygomatic processes of the frontal bone, very small and rounded infraorbital foramens that open above the fourth upper premolar metacone, upper carnassial teeth with a concave linguodistal outline, the reduction of the talon of the first upper molar, a very deep masseteric fossa, whose anterior margin reaches the mesial limit of the second lower molar, an extensive horizontal platform at the base of this fossa, and a very long and narrow angular apophysis. This species is the most ancient of the genus recorded for the Iberian Peninsula. 相似文献