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The wood mouse Apodemus sylvaticus is an opportunistic rodent that is found throughout most of the European mainland. It is present on many islands around the margins of the continent and in northern Africa. The species has been the subject of previous phylogeographical studies, although these have focussed on the more southerly part of its range. A substantial number of new samples, many of them from the periphery of the species' range, contribute to an exceptional dataset comprising 981 mitochondrial cytochrome b sequences. These new data provide sufficient resolution to transform our understanding of the survival of the species through the last glaciation and its subsequent re-colonization of the continent. The deepest genetic split that we found is in agreement with previous studies and runs from the Alps to central Ukraine, although we further distinguish two separate lineages in wood mice to the north and west of this line. It is likely that this part of Europe was colonized from two refugia, putatively located in the Iberian peninsula and the Dordogne or Carpathian region. The wood mouse therefore joins the growing number of species with extant populations that appear to have survived the Last Glacial Maximum in northern refugia, rather than solely in traditionally recognized refugial locations in the southern European peninsulas. Furthermore, the existence of a northern refugium for the species was predicted in a study of mitochondrial variation in a specific parasite of the wood mouse, demonstrating the potential value of data from parasites to phylogeographical studies. Lastly, the presence of related haplotypes in widely disparate locations, often on islands or separated by substantial bodies of water, demonstrates the propensity of the wood mouse for accidental human-mediated transport. [ABSTRACT FROM AUTHOR]

Ecogeographical patterns of morphological variation were studied in the Eurasian pygmy shrew Sorex minutus aiming to understand the species' morphological diversity in a continental and island setting, and within the context of previous detailed phylogeographical studies. In total, 568 mandibles and 377 skulls of S. minutus from continental and island populations from Europe and Atlantic islands were examined using a geometric morphometrics approach, and the general relationships of mandible and skull size and shape with geographical and environmental variables were studied. Samples were then pooled into predefined geographical groups to evaluate the morphological differences among them using analyses of variance, aiming to contrast the morphological and genetic relationships based on morphological and genetic distances and ancestral state reconstructions, as well as assess the correlations of morphological, genetic, and geographical distances with Mantel tests. We found significant relationships of mandible size with geographical and environmental variables, fitting the converse Bergmann's rule; however, for skull size, this was less evident. Continental groups of S. minutus could not readily be differentiated from each other by shape. Most island groups of S. minutus were easily discriminated from the continental groups by being larger, indicative of an island effect. Moreover, morphological and genetic distances differed substantially and, again, island groups were distinctive morphologically. Morphological and geographical distances were significantly correlated, although this was not the case for morphological and genetic distances, indicating that morphological variation does not reflect genetic subdivision in S. minutus. Our analyses showed that environmental variables and insularity had important effects on the morphological differentiation of S. minutus. [ABSTRACT FROM AUTHOR]

There is now considerable evidence for the survival of temperate species within glacial refugia that were situated at relatively high latitudes, notably the Carpathian Basin and Dordogne region in Europe. However, the prevalence of fossil remains in such locations is rarely matched by molecular evidence for their contribution to subsequent geographical and demographic expansion of the species in question. One obstacle to this has been insufficient analysis of modern samples from the relevant areas, in particular the parts of eastern Europe that surround the Carpathian refugium. In the present study, we examine the patterns of variation in mitochondrial DNA of the common vole ( Microtus arvalis), obtained from existing museum specimens and from newly-collected samples obtained in this area. We show that common voles from one of six extant mitochondrial DNA lineages have colonized most of the species' range in eastern Europe. We contend that the post-glacial dispersal of this lineage most likely originated from the Carpathian refugium, adding support to the argument that such northern refugia made an important contribution to existing genetic diversity in Europe. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, ●●, ●●-●●. [ABSTRACT FROM AUTHOR]