TOOTH BREAKAGE AND DIET - A COMPARISON OF BATS AND CARNIVORANS

Species of carnivorans that eat bone are believed to break teeth more often than those eating mainly meat. Two predictions that arise from t his hypothesis are that bats, which do not eat bone, will have a lower incidence of broken teeth than carnivorans and that smaller carnivora ns, which often feed heavily on arthropods and other insects, will exh ibit less tooth damage than larger carnivorans. We found no difference between bats and carnivorans in the proportion of skulls with broken or missing teeth in a sample including 10 species of carnivorans from ermines to bears, and 13 species of bats including some that eat insec ts, fruit, nectar and pollen, and blood. When the sample is expanded t o include larger carnivorans studied by Van Valkenburgh (1988), there is a significant difference in the incidence of tooth breakage, indica ting that the selection of species in the sample affects the results. Tooth breakage was strongly influenced by body size in carnivorans but not in bats. This evidence suggests that factors other than diet infl uence tooth breakage in mammals. We propose that lifespan, which incre ases with body size in carnivorans but not in bats, is a better predic tor of tooth breakage than diet.