Tooth breakage and diet: a comparison of bats and carnivorans

Abstract

Species of carnivorans that eat bone are believed to break teeth more often than those eating mainly meat. Two predictions that arise from this hypothesis are that bats, which do not eat bone, will have a lower incidence of broken teeth than carnivorans and that smaller carnivorans, which often feed heavily on arthropods and other insects, will exhibit 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 insects, fruit, nectar and pollen, and blood. When the sample is expanded to include larger carnivorans studied by Van Valkenburgh (1988), there is a signi®cant difference in the incidence of tooth breakage, indicating that the selection of species in the sample affects the results. Tooth breakage was strongly in¯uenced by body size in carnivorans but not in bats. This evidence suggests that factors other than diet in¯uence tooth breakage in mammals. We propose that lifespan, which increases with body size in carnivorans but not in bats, is a better predictor of tooth breakage than diet.

Costs of carnivory: tooth fracture in Pleistocene and Recent carnivorans

“…Contra Fenton et al. (1998), carnivorans break their teeth significantly more often than do bats, based on a comparison of the bat species ( N = 13) from their study and the 36 species of extant carnivorans in the present study ( P < 0.001, t = 5.457, d.f.…”

“…Although this may be true, comparisons with fossil material necessitate the use of fracture frequency on a per‐tooth basis because complete skulls are very rare and, in some cases, different partial specimens of dentary bones may have belonged to the same individual. In the present study, fracture frequency is examined on a per‐individual basis for comparison of extant carnivorans with the bat species described by Fenton et al. (1998) because that is the metric they used.…”

“…However, that study included nine species only, all of which were of large size (mass > 20 kg) and predominantly carnivorous. Subsequently, Fenton et al. (1998) compared tooth fracture frequencies between bats (13 species) and carnivorans (ten species) with a wider range of sizes and diets and found no significant relationship between diet and fracture incidence, unless the nine large carnivoran taxa from Van Valkenburgh (1988) were included.…”

Canine Length in Wild Male Baboons: Maturation, Aging and Social Dominance Rank

“…Enamel is lost during feeding, especially during the consumption of abrasives [ 35 ], and also when males open and close the mouth in canine displays or “yawns,” which sharpen the lower premolars and the upper and lower canines [ 25 – 26 ]. Male-male fights can blunt or break the canines, shortening them; predatory behaviors may also act as a potential source of canine damage [ 27 , 60 – 61 ]. Close to 28% of analyzed adult males in the present study showed at least one broken or blunt upper canine.…”

Finite element analysis of performance in the skulls of marmosets and tamarins

“…To date, there are no data to suggest that the skulls of mammals are stress‐limited. With the exception of relatively high frequencies of tooth fracture in some carnivores (Van Valkenberg & Ruff, 1987; Fenton et al. 1998; Van Valkenburgh, 2009), there is no known example of a mammal voluntarily loading its skull to failure during feeding.…”