Premolar microwear and tooth use in Australopithecus afarensis.

摘要: The mandibular third premolar (P3) of Australopithecus afarensis is notable for extensive morphological variability (e.g., metaconid presence/absence, closure the anterior fovea, root number) and temporal trends in crown length shape change over its 700 Ka time range. Hominins preceding A. have unicuspid, mesiodistally elongated P3s with smaller talonids, subsequent australopiths bicuspid, more symmetrically-shaped P3 crowns expanded talonids. For these features, intermediate and, thus, evinces incipient stages molarization. Here, we examine Phase II microwear compare it that africanus Cercocebus atys, an extant hard-object specialist, to assess whether role food processing changed afarensis. Premolar textures are also compared those molars look evidence functional differentiation along tooth row (i.e., foods different mechanical properties were processed by separate regions postcanine battery). Microwear examined mesial protoconid crest, site occlusion maxillary canine, same region Pan troglodytes determine can be useful identifying changes occlusal relationship between canine early Australopithecus. Finally, considered. Results indicate 1) both molar facets less complex than or C. atys; 2) differ, though not extent seen taxa eat hard tough items; 3) crest clearly distinct from P. troglodytes, indicating there no honing equivalent afarensis; 4) little on either facet. In sum, results provide routinely loaded premolars process objects function time.