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''Cynodesmus'' is an extinct genus of omnivorous canine which inhabited North America during the Oligocene living from 33.3—-26.3 Ma and existed for approximately . 〔http://paleobackup.nceas.ucsb.edu:8110/cgi-bin/bridge.pl?action=checkTaxonInfo&taxon_no=41207&is_real_user=1 ''Cynodesmus'': Basic info.〕 ''Cynodesmus'' was one of the first canids to truly look dog-like. At around in length, it was about the same size as a modern coyote, but had a shorter skull, heavier tail, and longer rump. The shape of its limbs suggests that ''Cynodesmus'' was not a very good runner compared to most other canids; it probably attacked prey from an ambush. Unlike modern dogs, it had five toes on each foot, bearing partially retractable claws. == Taxonomy == ''Cynodesmus'' once included numerous species of Oligocene and Miocene canid with highly carnivorous (hypercarnivorous) dentitions. A revision of the genus by Wang (1994) indicates that most species previously placed in ''Cynodesmus'' are unrelated to the type species, ''C. thooides''. These other species have been placed the genera ''Carpocyon'', ''Desmocyon'', ''Leptocyon'', ''Metatomarctus'', ''Osbornodon'', ''Otarocyon'', ''Paracynarctus'', ''Paratomarctus'', and ''Phlaocyon'' (Wang, 1994; Wang et al., 1999). Of these, only ''Osbornodon'' belongs in the same subfamily as ''Cynodesmus'', Hesperocyoninae. The remaining genera are placed in the subfamilies Borophaginae and Caninae. With unrelated species removed, ''Cynodesmus'' is currently restricted to the type species and the closely related ''C. martini'' (Wang, 1994). Studies using the old conception of ''Cynodesmus'' considered it to be the ancestor of ''Tomarctus'' (16-23 Ma) from which wolves, dogs, foxes and fennecs developed. The ''Cynodesmus'' is a good example of convergent evolution because of other species such as the ''Borophagus'', the largest and most dominant canids of this Pliocene epoch, both of which evolved from it.〔(North American Coyote )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cynodesmus」の詳細全文を読む スポンサード リンク
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