Carpals

Abstract

A capitate and scaphoid are the only carpal bones known from Sterkfontein, and are described here. These bones lack the derived features that characterize the wrist of modern humans and Neandertals solely on the geological and paleontological context of where these specimens were recovered. These elements are attributed to Australopithecus africanus because of where they were recovered, but recent discoveries of A. sediba and Homo naledi from the same geographical region underscore the complexity and diversity of hominin evolution in southern Africa throughout the Pleistocene and suggest extreme caution is needed in attributing isolated hominin elements to particular taxa. Functional interpretations based on single fossil carpals also must be treated cautiously until more reasonably complete fossil hominin hand skeletons are recovered. That said, however, the comparative morphology of these bones suggests that they belonged to hominins in which hand functional morphology was likely broadly similar to that of other early hominins, such as australopiths and Homo floresiensis.