Molar Microwear in Extant Small-bodied Faunivorous Mammals: an Analysis of Feature Density and Pit Frequency

This study quantitatively examined molar microwear in nine species of extant small-bodied faunivorous primates and microchiropterans. Comparative analyses were performed within the food category faunivory, both between hard- and soft-object feeding faunivores and between primarily insectivorous and carnivorous taxa. Additionally, microwear in faunivores was compared to that reported in the literature for frugivorous and folivorous primates. The results indicated that although insectivores and carnivores could not be distinguished by microwear analyses, hard-object faunivores (i.e., those that primarily consume beetles or actively comminute bone) can be readily distinguished from soft-object faunivores (i.e., moth, caterpillar, or vertebrate flesh specialists). The hard-object faunivores consistently exhibited greater pit frequencies (in excess of 40%). Furthermore, comparisons of these microwear data on faunivorous mammals to previous work on frugivorous and folivorous primates (Teaford, 1988, pers. comm.; Teaford and Runestad, 1992, pers. comm.; Teaford and Walker: American Journal of Physical Anthropology 64:191-200, 1984) permitted three observations to be made. 1) Faunivores tend to have higher mean feature densities than either frugivores or folivores, although these differences are not consistently statistically distinct. 2) Faunifores and frugivores that feed on hard-objects have comparable mean pit frequencies. 3) Although it is impossible to distinguish faunivores and folivores on the basis of metric analysis of gross molar morphology, this distinction can be made on microwear criteria. Both hard- and soft-object faunivores exhibit much higher mean pit frequencies than primarily folivorous species.