COMPARATIVE PHYLOGEOGRAPHY AND POSTGLACIAL COLONIZATION ROUTES IN EUROPE

The Quaternary cold periods in Europe are thought to have heavily infl uenced the amount and distribution of intraspecific genetic variation in both animals and plants. The phylogeographies of 10 taxa, including mammals (Ursus arctos, Sorex spp., Crocidura suaveolens, Arvicola spp .), amphibians (Triturus spp.), arthropods (Chorthippus parallelus), a nd plants (Abies alba, Picea abies, Fagus sylvatica, Quercus spp.), we re analysed to elucidate general trends across Europe. Only a small de gree of congruence was found amongst the phylogeographies of the 10 ta xa, but the likely postglacial colonization routes exhibit some simila rities. A Brooks parsimony analysis produced an unrooted area phylogra m, showing that: (i) the northern regions were colonized generally fro m the Iberic and Balkanic refugia; and (ii) the Italian lineages were often isolated due to the presence of the Alpine barrier. The comparis on of colonization routes highlighted four main suture-zones where lin eages from the different refugia meet. Some of the intraspecific genet ic distances among lineages indicated a prequaternary divergence that cannot be connected to any particular cold period, but are probably re lated mainly to the date of arrival of each taxon in the European cont inent. As a consequence, molecular genetics so far appears to be of li mited use in dating Quaternary events.