Red deer (Cervus elaphus) is one of the most important and widespread game species throughout Europe, with an estimated population size exceeding half a million. The current distribution of red deer is assumed to be strongly influenced by human activities in addition to the colonization history and the last glaciation event. Due to the stationary habits of female social groups, the establishment of new populations by human translocations has often been reported. There are even historical data describing such translocations from the Viking sagas.
Worldwide, red deer has a circumboreal distribution, and genetic investigations have pointed to a central Asian origin. Despite its prominence as a big game animal, a detailed investigation of the genetic relationships of red deer populations in Europe has not been performed until now. As a consequence, the large (geographic) scale impacts of human translocations have not been known. In an article published in Journal of Biogeography, Anna Skog and co-workers report on the mitochondrial phylogeography of red deer in Europe.
Skog et al. analysed two regions within the mitochondrial genome from most European populations and by phylogenetic analyses of the gene sequences found that there are three main evolutionary lineages in Europe. The southern lineage is the most ancient. This genetic lineage is found in Africa in Sardinia/Corsica and at one site in Spain. The rest of Europe is populated by two genetically distinct red deer lineages, showing a western/northern and an eastern distribution, respectively.
Within each main lineage there are several variants, and the diversity and distribution of these variants give indications about putative glacial refugia. Skog and co-workers suggest that such refugia have existed in Spain (the Iberian Peninsula) and in the Balkans. Thus, the Western and Eastern clades have survived during the last glaciation in these regions and subsequently repopulated Europe from their respective refugia. This is further substantiated by calculations of how old the Western and Eastern clades are. Using the mutations separating the clades and estimated mutation rates for the genes, they calculated the split between the Western and Eastern clades to date at least 150,000 years ago, thus pre-dating the last glaciation.
Somewhat surprisingly, the analysis revealed no obvious signs of long-distance human translocations. While there is little doubt that this has happened in the past, the data of Skog et al. indicate that translocations have predominantly been short distance, or involved animals being translocated between regions where animals belong to the same main clade.
Source paper: Skog, A., Zachos, F.E., Rueness, E.K., Feulner, P.G.D., Mysterud, A., Langvatn, R., Lorenzini, R., Hmwe, S.S., Lehoczky, I., Hartl, G.B., Stenseth, N.C. & Jakobsen, K.S. (2008) Phylogeography of red deer (Cervus elaphus) in Europe. Journal of Biogeography, doi: 10.1111/j.1365-2699.2008.01986.x