Spatial patterns of genetic diversity across European subspecies of the mountain hare, Lepus timidus L.

Abstract

Fossil evidence shows that populations of species that currently inhabit arctic and boreal regions were not isolated in refugia during glacial periods, but instead maintained populations across large areas of central Europe. These species commonly display little reduction in genetic diversity in northern areas of their range, in contrast to many temperate species. The mountain hare currently inhabits both temperate and arctic-boreal regions. We used nuclear microsatellite and mtDNA sequence data to examine population structure and alternate phylogeographic hypotheses for the mountain hare, that is, temperate type (lower genetic diversity in northern areas) and arctic-boreal type (high northern genetic diversity). Both data sets revealed concordant patterns. Highest allelic richness, expected heterozygosity and mtDNA haplotype diversity were identified in the most northerly subspecies, indicating that this species more closely maps to phylogeographic patterns observed in arctic-boreal rather than temperate species. With regard to population structure, the Alpine and Fennoscandian subspecies were most genetically similar (F ST E0.1). These subspecies also clustered together on the mtDNA tree and were assigned with highest likelihood to a common Bayesian cluster. This is consistent with fossil evidence for intermediate populations in the central European plain, persisting well into the postglacial period. In contrast, the geographically close Scottish and Irish populations occupied separate Bayesian clusters, distinct clades on the mtDNA maximum likelihood tree and were genetically divergent from each other (F ST 40.4) indicating the influence of genetic drift, long isolation (possibly dating from the late glacial era) and/ or separate postglacial colonisation routes.

Niche overlap of mountain hare subspecies and the vulnerability of their ranges to invasion by the European hare; the (bad) luck of the Irish

“…There are five extant European mountain hare subspecies differentiated by morphophysiological characteristics, behaviour, and ecology (Angerbjörn and Flux 1995). There is generally low genetic differentiation between subspecies, indicative of a post-glacial panmictic European population, which subsequently underwent fragmentation, isolation, and divergence (Hamill et al 2006). The most widespread subspecies, recognised as the typical form (and thus presumed similar to the ancestral type), is the northern hare (L. timidus timidus, Linnaeus 1758) which inhabits tundra (in the north) and boreal forest (further south) in the Arctic and Fennoscandia (Angerbjörn and Flux 1995).…”

European phylogeography of the common frog (Rana temporaria): routes of postglacial colonization into the British Isles, and evidence for an Irish glacial refugium

“…However, a high divergence between British and Irish populations has been found in certain species. For example, Hamill et al (2006) found that populations of mountain hares (L. timidus) in Scotland and Ireland belonged to different mitochondrial DNA (mtDNA) clades and showed high divergence based on nuclear microsatellite data, reporting F ST values above 0.4.…”

Nonreceding hare lines: genetic continuity since the Late Pleistocene in European mountain hares (Lepus timidus)

“…As the "random histories" failed to provide a clear picture of the demographic history of L. The statistical power for the models of the "old-change test" was moderate but rose to high 430 levels when a Bayes factor of 2.0 was used as a threshold criterion (Table S6) (Hamill et al, 2006;Suchentrunk et al, 1999). However, the historically high 461 levels of diversity revealed in our analyses suggest that the mountain hare has maintained 462 diversity over time unlike many classic arctic/alpine specialists.…”