Thewissen, J. G. M. Williams, E. M. Roe, L. J. Hussain, S. T. 2001 Skeletons of terrestrial cetaceans and the relationship of whales to artiodactyls Nature 413 277-281 Arctocyon Hyopsodus Phenacodus Meniscotherium Andrewsarchus Eoconodon Hapalodectes Dissacus Ankalagon Sinonyx Pachyaena Mesonyx Synoplotherium Harpagolestes Pakicetus Ambulocetus D_pakistanensis D_secans Archaeotherium Elomeryx Hippopotamus Hexaprotodon Sus Agriochoerus Poebrotherium Tragulus Haplobunodontid Cebochoerid Raoellid Osteology Maximum Parsimony Based on reanalysis of the original matrix. Thewissen_etal_2001a