Genetic diversity and phylogeography of the European roe deer: the refuge area theory revisited

The extant taxa of central and northern Europe are commonly believed to derive from Pleistocene ancestors, who moved to the north from three separate glacial refugia: the Iberian and Italian peninsulae, as well as the southern Balkans. The issue of postglacial dispersal patterns was addressed through the investigation of population structure and phylogeography of the European roe deer, Capreolus capreolus. The genetic diversity in 376 individuals representing 14 allegedly native populations across their European range was assessed, using ten autosomal microsatellite loci and restriction fragment length polymorphisms of the mitochondrial D-loop and NADH dehydrogenase 1 gene segments. Our results suggest the existence of three major genetic lineages of roe deer in Europe. One comprises populations in the south-western limit of the species’ distribution (i.e. Iberia), where an internal substructure splits a northern from a southern sublineage. A second lineage includes populations of southern and eastern Europe, as well as a separate sublineage sampled in central-southern Italy, where the existence of the subspecies Capreolus c. italicus was supported. In central-northern Europe, a third lineage is present, which appeared genetically rather homogeneous, although admixed, and equally divergent from both the eastern and western lineages. Current patterns of intraspecific genetic variation suggest that postglacial recolonization routes of this cervid to northern Europe could be due to range expansion from one or more refugia in central-eastern Europe, rather than proceeding from the Mediterranean areas.