Spatial partitioning of allozyme variability in European mountain hares (Lepus timidus): gene pool divergence across a disjunct distributional range?

To investigate if the postglacial dispersion of mountain hares (Lepus timid us) into the present geographically separated ranges in Europe has produced marked gene pool differentiation, 209 individuals from Scandinavia, Russia , the Alps, Scotland, and Ireland were screened for allozymic variability a t 40 structural gene loci by horizontal starch gel electrophoresis. Polymor phisms were detected at 13 loci. Most alleles were identical with those of brown hares (Lepus europaeus) studied earlier in Europe. Average expected h eterozygosity (2.0-5.0 %) and rates of polymorphism (8.5-29.4 %) in regions or subspecies were comparable to those of local samples of European brown hares studied earlier. Despite a high amount (31.3 %) of "private alleles", genetic distances (NEI's 1978 D: 0.000-0.008 among subspecies, and 0.000-0 .017 among regions) were similar to those found among local samples of cent ral European brown hares. This indicates low genetic differentiation among gene pools of subspecies or regions. Also, relatively low mean F-ST values (0.157 for regions, 0.14 for subspecies) and low numbers of significantly d iffering allele frequencies indicated little genetic differentiation. WRIGH T'S (1978) hierarchical F-statistics revealed that less than 1 % of the rel ative genetic variation was partitioned among subspecies but 13.6 % among r egions within subspecies. All results conform to the hypothesis of a quite panmictic gene pool of late-glacial and postglacial mountain hares in Europ e. They also support the view that no severe drift has occurred in postglac ial populations during the colonization of the present ranges.