Premium
Species attribution of the Swartkrans member 1 first metacarpals: SK 84 and SKX 5020
Author(s) -
Trinkaus Erik,
Long Jeffrey C.
Publication year - 1990
Publication title -
american journal of physical anthropology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.146
H-Index - 119
eISSN - 1096-8644
pISSN - 0002-9483
DOI - 10.1002/ajpa.1330830403
Subject(s) - australopithecus , morphology (biology) , biology , evolutionary biology , homo erectus , zoology , paleontology , pleistocene
Susman ( Am. J. Phys. Anthropol. 75: 277–278, 79: 451–474; Science 240: 781–784; In FE Grine (ed): Evolutionary History of the “Robust” Australopithecines. New York: Aldine de Gruyter, pp. 149–172) has attributed the morphologically similar SK 84 and SKX 5020 hominid first metacarpals to Homo erectus and Australopithecus robustus , respectively, and has inferred that both species exhibited derived pollical morphologies, indicating refined precision grips. Consideration of the structure of his taphonomic arguments indicates that there are no adequate nonmorphological reasons to attribute these specimens securely to one or the other of the craniodentally represented species at Swartkrans. His morphological arguments fail to note any significant differences between the two specimens. Only the contrast in size between the small SK 84 and large SKX 5020 bones might warrant a species distinction; yet comparison of their length ratio to distributions of modern human first metacarpal length ratios indicates that it is not possible to reject conclusively the null hypothesis that they are conspecific. Therefore, early hominid adaptive scenarios based on a derived Homo ‐like manual functional morphology in A. robustus remain without a secure paleontological basis.