Arboreality and Bipedality in the Hadar HominidsSusman R.L. · Stern, Jr. J.T. · Jungers W.L.
Department of Anatomical Sciences, Health Sciences Center, SUNY at Stony Brook, N.Y., USA
Numerous studies of the locomotor skeleton of the Hadar hominids have revealed traits indicative of both arboreal climbing/suspension and terrestrial bipedalism. These earliest known hominids must have devoted part of their activities to feeding, sleeping and/or predator avoidance in trees, while also spending time on the ground where they moved bipedally. In this paper we offer new data on phalangeal length and curvature, moφhology of the tarsus and metatarsophalangeal joints, and body proportions that further strengthen the argument for arboreality in the Hadar hominids. We also provide additional evidence on limb and pedal proportions and on the functional anatomy of the hip, knee and foot, indicating that the bipedality practiced at Hadar differed from that of modern humans. Consideration of the ecology at Hadar, in conjunction with modern primate models, supports the notion of arboreality in these earliest australopithecines. We speculate that selection for terrestrial bipedality may have intensified through the Plio-Pleistocene as forests and woodland patches shrunk and the need arose to move increasingly longer distances on the ground. Only with Homo erectus might body size, culture and other factors have combined to ‘release’ hominids from their dependence on trees.
© 1984 S. Karger AG, Basel
R.L. Susman, Department of Anatomical Sciences, Health Sciences Center, SUNY at Stony Brook, Stony Brook, NY 11794 (USA)
Published online: September 11, 2008
Number of Print Pages : 44
Folia Primatologica (International Journal of PrimatologyInternationale Zeitschrift für PrimatologieJournal international de Primatologie)
Vol. 43, No. 2-3, Year 1984 (Cover Date: 1984)
Journal Editor: Crompton R.H. (Liverpool)
ISSN: 0015–5713 (Print), eISSN: 1421–9980 (Online)
For additional information: http://www.karger.com/FPR