Two closely related species differ in their regional genetic differentiation despite admixing.
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ABSTRACT:
SUBMITTER: Schmidt L
PROVIDER: S-EPMC5817946 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Alexei V. Abramov, Andrey Yu. Puzachenko, and Igor L. Tumanov (2016) A morphological differentiation (i.e., the amount of morphological space occupied) in two polecat species, Mustela putorius and M. eversmanii, has been studied. These closely related species are similar in the body size, the age of origin, and many aspects of their natural history. We have used cranial characters to estimate some parameters of morphological diversity, to compare 'morphological niche breadth' occupied by polecats in the morphological space and their overlap, assuming that variation in the characteristics of morphological diversity could be reflected in the extent of adaptive diversification. A comparison of diversity based on 23 cranial characters shows that the polecats occupied distinct areas of the morphospace. Both skull 'size' and 'shape' characters are important components of the morphological differentiation between M. putorius and M. eversmanii. It seems that the difference between these polecat species is accounted for the ecological pattern rather than the phylogenetic one. Resource partitioning and the lessening of their ecological niches' overlap in two sympatric carnivores could apparently explain the observed differences of their morphospaces. The morphological diversity of the European polecat is higher than that of the steppe polecat. A possible explanation of this phenomenon is likely to lie in the differences between prey ranges of these species. The morphological diversification in M. putorius could be facilitated by its adaptations to forest habitats of the temperate zone with a wide range of potential prey, whereas M. eversmanii could have evolved under more severe conditions of arid Eurasian habitats with a possible prey specialization.
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Project description:The species status of two closely related Chinese oaks, Quercus liaotungensis and Q. mongolica, has been called into question. The objective of this study was to investigate the species status and to estimate the degree of introgression between the two taxa using different approaches.Using SSR (simple sequence repeat) and AFLP (amplified fragment length polymorphism) markers, we found that interspecific genetic differentiation is significant and higher than the differentiation among populations within taxa. Bayesian clusters, principal coordinate analysis and population genetic distance trees all classified the oaks into two main groups consistent with the morphological differentiation of the two taxa rather than with geographic locations using both types of markers. Nevertheless, a few individuals in Northeast China and many individuals in North China have hybrid ancestry according to Bayesian assignment. One SSR locus and five AFLPs are significant outliers against neutral expectations in the interspecific FST simulation analysis, suggesting a role for divergent selection in differentiating species.All results based on SSRS and AFLPS reached the same conclusion: Q. liaotungensis and Q. mongolica maintain distinct gene pools in most areas of sympatry. They should therefore be considered as discrete taxonomic units. Yet, the degree of introgression varies between the two species in different contact zones, which might be caused by different population history or by local environmental factors.
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