Molecular Phylogeny of the Marmots (Rodentia: Sciuridae): Tests of Evolutionary and Biogeographic Hypotheses

摘要: There are 14 species of marmots distributed across the Holarctic, and despite extensive systematic study, their phylogenetic relationships remain largely unresolved. In particular, compre- hensive studies have been lacking. A well-supported phylogeny is needed to place numerous ecological behavioral on in an evolutionary context. To address this situation, we obtained complete cytochrome (cyt) b sequences for 13 a partial sequence 14th. We applied statistical approach both estimation hypothesis testing, us- ing parsimony maximum likelihood-based methods. conducted tests suite previously proposed hypotheses biogeographic histories. The cyt data strongly support monophyly Marmota western montane clade Nearc- tic. Although some other scenarios cannot be rejected, results consistent with initial di- versification North America, followed by invasion subsequent rapid diversification Palearctic. These analyses reject two major competing M. broweri's relationships—namely, that it sister camtschatica eastern Siberia, related closely caligata Nearctic. Alaskan distribution broweri best explained as reinvasion from Palearctic, but Nearctic origin can not rejected. Several conven- tionally recognized groups also Social evolution has homoplastic, large colonial systems evolving convergently. do provide unam- biguous resolution several basal nodes Palearctic radiation, leaving aspects pelage karyotypic equivocal. {Beringia; b; Holarctic; testing; Mar- mota; phylogenetics.}