NEW DISCOVERIES OF AUSTRALOPITHECUS AT MAKA IN ETHIOPIA

THE taxonomy of Australopithecus afarensis, the oldest known hominid s pecies, has been a matter of debate since its description in 1978 (ref . 1). Some authorities regard all specimens assigned to A. afarensis a s belonging to a single taxon2-4 whereas others regard the Tanzanian a nd Ethiopian specimens as each representing a different species5,6. Fu rther controversy surrounds the issues of sexual dimorphism and locomo tion among these hominids. Resolution of these problems would shed lig ht on hominid phylogeny in general and on the ancestry of later Austra lopithecus and Homo. Fossils discovered in the Afar of Ethiopia in 199 0 constitute the first major addition to the 3-4 million year (Myr) ho minid record since the 1970s. We report here the discovery of new foss ils from Maka, dated to 3.4 Myr ago, which provide powerful support fo r the interpretation of A. afarensis as a single, ecologically diverse , sexually dimorphic, bipedal Pliocene primate species whose known ran ge encompassed Ethiopia and Tanzania.