Incisor microwear and feeding behavior in Alouatta seniculus and Cebus olivaceus

Dental microwear features on the labial surfaces of maxillary central incisors of wild-shot museum specimens of Cebus olivaceus (n = 11) and Alouatta seniculus (n = 7) were examined at 200 × by polarized light microscopy. While wear scratch orientation patterns do not differ between the two samples, Cebus has a significantly higher density of wear features, and displays scratches that extend further cervically. Preliminary observations (n = 50 hours) on anterior tooth use in these species at Hato Masaguaral, in the Llanos of Venezuela, provide suggestions regarding how foraging patterns reported in the literature relate to these microwear differences. Cebus uses its front teeth more frequently in the manipulation of a greater variety of objects than does Alouatta.