PARALLEL EVOLUTION IN THE HOMINOID TRUNK AND FORELIMB

The evolutionary history of the living hominoids has remained elusive despite years of exploration and the discovery of numerous Miocene fos sil ape species. Part of the difficulty can be attributed to the chang ing nature of our views about the course of hominoid evolution. In the 1950s and 1960s, individual Miocene taxa were commonly viewed as the direct ancestors of specific living ape species, suggesting an early d ivergence of the modern lineages.(1-5) However, in most cases, the Mio cene forms were essentially ''dental apes,'' resembling extant species in dental and a few cranial features, but possessing more primitive p ostcranial features that suggested arboreal quadrupedalism rather than suspensory habits. With the introduction of molecular methods of phyl ogenetic reconstruction and the increasing use of cladistic analysis, it has become apparent that the radiation leading to the modern homino ids was somewhat more recent than had been believed, and that most of the Miocene hominoid species had little to do with the evolutionary hi story of the living apes.(6)