Earliest complete hominin fifth metatarsal-Implications for the evolution of the lateral column of the foot

• Published in: American journal of physical anthropology Vol. 140; no. 3; pp. 532 - 545
• Main Authors: Zipfel, Bernhard, DeSilva, Jeremy M., Kidd, Robert S.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.11.2009; Wiley-Liss
• Subjects: Africa; Anatomy, Comparative; Animals; Anthropological analysis; Anthropological methods; Anthropometry; Biological anthropology; Biological Evolution; bipedalism; Comparative analysis; Female; Foot - anatomy & histology; fossil metatarsal; Fossils; Generalities; Hominidae - anatomy & histology; Hominids; hominins; Human evolution; Human paleontology; Humans; Locomotion - physiology; Male; Mankind origin and evolution; Metatarsal Bones - anatomy & histology; Methodology and general studies; Multivariate Analysis; Paleoanthropology; Physical anthropology; Prehistory and protohistory; South Africa; Southern and East Africa; Sterkfontein; South Africa; Africa; Homininae; Bipedalism; Human palaeontology; Sterkfontein; hominins; Bone; fossil metatarsal; Physical anthropology; Foot
• ISSN: 0002-9483; 1096-8644
• DOI: 10.1002/ajpa.21103

StW 114/115, from Sterkfontein, South Africa, is the earliest complete hominin fifth metatarsal. Comparisons of StW 114/115 to modern humans, extant apes, and partial hominin metatarsals AL 333‐13, AL 333‐78, SKX 33380, OH 8, and KNM‐ER 803f reveal a similar morphology in all six fossils consistent with habitual bipedality. Although StW 114/115 possesses some primitive characters, the proximal articular morphology and internal torsion of the head are very human‐like, suggesting a stable lateral column and the likely presence of lateral longitudinal and transverse tarsal arches. We conclude that, at least in the lateral component of the foot of the StW 114/115 individual, the biomechanical pattern is very similar to that of modern humans. This, however, may not have been the case in the medial column of the foot, as a mosaic pattern of hominin foot evolution and function has been suggested. The results of this study may support the hypothesis of an increased calcaneo‐cuboid stability having been an early evolutionary event in the history of terrestrial bipedalism. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.