Post-mortem wear as indicator of taphonomic processes affecting enamel surfaces of hominin teeth from Laetoli and Olduvai (Tanzania): implications to dietary interpretations

Abstract

The buccal microwear pattern of premolar and molar teeth has been linked to the composition of the ingested diet in human populations, both extant and fossil. However, numerous enamel surfaces observed for microwear analyses show microscopic damage that can be attributed to post-mortem taphonomic processes, not related to dietary habits. Post-depositional processes may greatly affect enamel surfaces, occasionally hindering dietary reconstructions based on dental microwear patterns. The present study analyses the damage patterns that can be observed on fossil Hominin teeth from the sites of Laetoli and Olduvai (Tanzania) to differentiate between ante-mortem and post-mortem processes. The results obtained show that post-mortem wear can be easily differentiated from ante-mortem abrasion for its distinct effects, mainly consisting of obliteration of enamel features. The frequency of abraded surfaces in the samples studied is considerably high. Despite the great antiquity of the remains studied, patches of well preserved enamel can still be distinguished in a number of teeth. Well preserved enamel surfaces can be discriminated for their polished appearance and the presence of distinct microwear features.