Morphological correlates of the first metacarpal proximal articular surface with manipulative capabilities in apes, humans and South African early hominins

Marchi, Damiano; Proctor, Daniel J.; Huston, Emma; Nicholas, Christina L. and Fischer, Florian (2017): Morphological correlates of the first metacarpal proximal articular surface with manipulative capabilities in apes, humans and South African early hominins. In: Comptes Rendus Palevol, Vol. 16, No. 43256: pp. 645-654

Abstract

This study quantifies the metacarpal 1 (MC 1) proximal articular surface using three-dimensional morphometrics in extant hominids and fossil hominins (SK 84, cf. Paranthropus robustus/Homo erectus and StW 418, Australopithecus africanus) to understand which characteristics of the proximal metacarpal 1 are potentially correlated with human manipulative abilities and if they can be used in a paleoanthropological setting. A principal components (PC) analysis was used to compare MC 1 proximal articular surface shape and ANOVA and Tukey's HSD post-hoc tests were conducted to determine differences among groups. Homo is significantly different from nonhuman hominids having a less radioulnarly and dorsovolarly curved articular surface. All nonhuman hominids have more curved articular surface with Gorilla showing the most curved joint. Moreover, this study highlights the presence of a radially extended surface in Homo that may be related to the greater thumb abduction in human manipulation activities. Both fossils analyzed show a great ape-like MC 1 proximal articular surface which, associated with recent trabecular and archaeological evidence, may indicate that the ability to make/use stone tools preceded the morphological adaptations associated today with such behavior. (C) 2016 Academie des sciences.

• Item Type: Journal article
• Faculties: Medicine
• Subjects: 600 Technology > 610 Medicine and health
• ISSN: 1631-0683
• Language: English