Molecular phylogenies of the genus Marmota (Rodentia, Sciuridae): comparative analysis [Phylogénies moleculaires du genre Marmota (Rodentia, Sciuridae) : analyse comparative].

Résumé

Phylogenetic reconstructions of the genus Marmota were made using mitochondrial genes cit b (Thomas and Martin, 1993, Lyapunova et al. 1995, Steppan et al. 1999, Kruckenhauser et al. 1999) and D-loop (our data) sequences, DNA-DNA hybridization (Giboulet et al. 1997) and inter-SINEs nuclear DNA pattern (our data) as molecular markers. All these studies are evidence of a recent origin and North-American origin of marmots. Most of the data show Nearctic and Palearctic groups of species, but their compositions are different. M. monax and M. browery are grouped with Nearctic or Palearctic marmots on different trees. Existence on mtDNA and nDNA trees of closed related species groups, such as bobak- and camtschatica-groups, reflects a recent Pleistocene evolution. Low mtDNA and high nDNA genetic distances in pair M. menzbieri – M. caudata probably indicates their remote hybridization. A genetic affinity of M. vancouverensis and M. caligata shows short time of their separate evolution for accumulation of species specific molecular differences. Significance of different molecular markers in reconstruction of marmot phylogeny is discussed. A consensus phylogenetic tree of the genus Marmota is proposed.