Skeleton of Diacodexis, Oldest Known Artiodactyl

Science  07 May 1982:
Vol. 216, Issue 4546, pp. 621-623
DOI: 10.1126/science.216.4546.621


A nearly complete skeleton of early Eocene Diacodexis, the oldest known member of the mammalian order Artiodactyla, is described. Its slender, elongate limb elements indicate that Diacodexis was highly cursorial and closer in postcranial adaptations to tragulids and other primitive ruminants than to living or extinct nonruminant artiodactyls. Its skeletal specializations call into question the widespread notion that Diacodexis was the ancestor of all later artiodactyls.