Adaptation to suspensory locomotion in Australopithecus sediba

Thomas R Rein; Terry Harrison; Kristian J Carlson; Katerina Harvati

doi:10.1016/j.jhevol.2016.12.005

Adaptation to suspensory locomotion in Australopithecus sediba

J Hum Evol. 2017 Mar:104:1-12. doi: 10.1016/j.jhevol.2016.12.005. Epub 2017 Feb 3.

Authors

Thomas R Rein¹, Terry Harrison², Kristian J Carlson³, Katerina Harvati⁴

Affiliations

¹ Department of Anthropology, Central Connecticut State University, 1615 Stanley Street, New Britain, CT 06053, USA; Paleoanthropology, Senckenberg Center for Human Evolution and Paleoenvironment, Eberhard Karls Universität Tübingen, Rümelinstr. 23, 72070 Tübingen, Germany. Electronic address: rein@ccsu.edu.
² Center for the Study of Human Origins, Department of Anthropology, New York University, 25 Waverly Place, New York, NY 10003, USA.
³ Department of Cell & Neurobiology, Keck School of Medicine, University of Southern California, 1333 San Pablo Street, Los Angeles, CA 90033, USA; Evolutionary Studies Institute, University of the Witwatersrand, Wits 2050, South Africa.
⁴ Paleoanthropology, Senckenberg Center for Human Evolution and Paleoenvironment, Eberhard Karls Universität Tübingen, Rümelinstr. 23, 72070 Tübingen, Germany.

PMID: 28317552
DOI: 10.1016/j.jhevol.2016.12.005

Abstract

Australopithecus sediba is represented by well-preserved fossilized remains from the locality of Malapa, South Africa. Recent work has shown that the combination of features in the limb skeleton of A. sediba was distinct from that of earlier species of Australopithecus, perhaps indicating that this species moved differently. The bones of the arm and forearm indicate that A. sediba was adapted to suspensory and climbing behaviors. We used a geometric morphometric approach to examine ulnar shape, potentially identifying adaptations to forelimb suspensory locomotion in A. sediba. Results indicated suspensory capabilities in this species and a stronger forelimb suspensory signal than has been documented in Australopithecus afarensis. Our study confirms the adaptive significance of functional morphological traits for arboreal movements in the locomotor repertoire of A. sediba and provides important insight into the diversity and mosaic nature of locomotor adaptations among early hominins.

Keywords: Australopithecus afarensis; Functional morphology; Geometric morphometrics; South Africa; Ulna.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Adaptation, Biological
Animals
Fossils / anatomy & histology*
Hominidae / anatomy & histology*
Locomotion*
Ulna / anatomy & histology*