Title

An Early Australopithecus Afarensis Postcranium from Woranso-Mille, Ethiopia

Publication Title

Proceedings of the National Academy of Sciences of the United States of America

Publication Date

7-6-2010

Document Type

Conference Proceeding

Keywords

bipedality, human evolution, upright walking, hominid, thorax

Disciplines

Anthropology

Abstract

Only one partial skeleton that includes both forelimb and hindlimb elements has been reported for Australopithecus afarensis. The di minutive size of this specimen (A.L 288-1 ["Lucy"]) has hampered our understanding of the paleobiology of this species absent the potential impact of allometry. Here we describe a large-bodied (i.e., well within the range of living Homo) specimen that, at 3.58 Ma, also substantially antedates A.L. 288-1. It provides fundamental evidence of limb proportions, thoracic form, and locomotor heri tage in Australopithecus afarensis. Together, these characteristics further establish that bipedality in Australopithecus was highly evolved and that thoracic form differed substantially from that of either extant African ape.