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Recent studies highlighted the potential role of cryptic glacial refugia for temperate taxa in Europe beyond the Mediterranean peninsulas. To further investigate phylogeographic features of the European pine marten (Martes martes) in previously identified cryptic refugia located in central–western Europe, we analysed the hyper-variable diagnostic fragment of the mitochondrial control region in a total of 134 specimens, allowing for reliable comparisons with previous genetic studies of the species. We included samples from eight different European countries in central–western Europe (Belgium, France, Luxembourg and the Netherlands), in south–western Europe (Spain), in north–central Europe (Denmark) and in central Europe (Germany and Poland). The sequences collapsed in 17 haplotypes, which allowed us to determine the genetic composition of the pine marten populations throughout central–western Europe. Overall, our results showed that the population genetic variation, estimated by the standardised haplotype diversity, was high (0.400 ≤ Hs ≤ 0.762), and it was considerably higher in Germany (0.762) and the Netherlands (0.722) compared to the other countries. The nucleotide diversity was relatively low (0.002 ≤ π ≤ 0.016) even in Germany and the Netherlands (0.016 and 0.014, respectively), suggesting relatively small, long-term effective population sizes or severe bottlenecks. Out of the 17 haplotypes found in our study area, 13 were unique and limited to a single country: one in Denmark, one in Spain, four in Poland and seven in the Netherlands. The pairwise genetic distance ranged from 0.001 to 0.032 and did not show any evident correlation with the geographic distances between the populations. A genealogical relationship network was constructed, which provided evidence for a recent origin of many of the unique haplotypes. Approximately 82 % of the samples analysed in this study belonged to haplotypes grouped into a previously identified central–northern European phylogroup of the species. Our results support previous findings, indicating low contribution of southern refugial populations to the postglacial recolonization of central–western Europe and a predominant contribution of pine marten populations that survived the Last Glacial Maxima in cryptic northern refugia.
Here we present the first attempt to use the BovineSNP50 Illumina Genotyping BeadChip for genome-wide screening of European bison Bison bonasus bonasus (EB), two subspecies of American bison: the plains bison Bison bison bison (PB), the wood bison Bison bison athabascae (WB) and seven cattle Bos taurus breeds. Our aims were to (1) reconstruct their evolutionary relationships, (2) detect any genetic signature of past bottlenecks and to quantify the consequences of bottlenecks on the genetic distances amongst bison subspecies and cattle, and (3) detect loci under positive or stabilizing selection. A Bayesian clustering procedure (STRUCTURE) detected ten genetically distinct clusters, with separation among all seven cattle breeds and European and American bison, but no separation between plain and wood bison. A linkage disequilibrium based program (LDNE) was used to estimate the effective population size (N e) for the cattle breeds; N e was generally low, relative to the census size of the breeds (cattle breeds: mean N e = 299.5, min N e = 18.1, max N e = 755.0). BOTTLENECK 1.2 detected signs of population bottlenecks in EB, PB and WB populations (sign test and standardized sign test: p = 0.0001). Evidence for loci under selection was found in cattle but not in bison. All extant wild populations of bison have shown to have survived severe bottlenecks, which has likely had large effects on genetic diversity within and differentiation among groups.
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