Incisor microwear, diet, and tooth use in three Amerindian populations

Incisor microwear patterns have been shown to reflect aspects of diet and i ngestive behaviors in a wide range of nonhuman primates. While some studies have suggested that anterior dental microwear might be used to infer unusu al front tooth use practices in archaeological populations, quantitative wo rk on modern human incisors has thus far been limited. In this study we exa mined dental microwear on the maxillary central incisors of three groups of humans: Aleutian Islanders (n = 16), Arikara from the Mobridge Site in Sou th Dakota (n = 15), and a Late Woodland Bluff sample from Jersey County, Il linois (n = 17). High-resolution replicas were prepared and examined by sca nning electron microscopy following conventional procedures. Photomicrograp hs were taken at consistent locations on the labial surface, and microwear was quantified using Microware 3.0 (Ungar, 1997). Statistical test results revealed significant differences among the groups in microwear feature dens ities, sizes, and shapes. The Aleut, Arikara, and Illinois Bluff samples sh owed a gradient of increasing microwear density, increasing linearity in fe ature shape, and decreasing feature size. These differences evidently corre spond to amount of meat consumption, and apparently to degree of use of the incisors in heavy loading. No differences were observed between groups in heterogeneity of feature orientations, and no sex-related differences were found. Associations between incisor microwear on the one hand and subsisten ce practice and anterior tooth use on the other likely have important impli cations for the study of hominid paleobiology. (C) 1999 Wiley-Liss, Inc.