Origin of Whales from Early Artiodactyls: Hands and Feet of Eocene Protocetidae from Pakistan

Abstract

Partial skeletons of two new fossil whales, Artiocetus clavis and Rodhocetus balochistanensis, are among the oldest known protocetid archaeocetes. These came from early Lutetian age (47 million years ago) strata in eastern Balochistan Province, Pakistan. Both have an astragalus and cuboid in the ankle with characteristics diagnostic of artiodactyls; R. balochistanensis has virtually complete fore- and hind limbs. The new skeletons are important in augmenting the diversity of early Protocetidae, clarifying that Cetacea evolved from early Artiodactyla rather than Mesonychia and showing how early protocetids swam.