Craniodental traits and interaction in the bite force of tropical
frugivore bats (Phyllostomidae: Stenodermatinae)
Abstract
1. Phyllostomid bats exhibit great diversity in skull size and
morphology that reflects the degree of resource division and ecological
overlap in the group. In particular, Stenodermatinae has high
morphological diversification associated with cranial and mandibular
traits that is associated with the ability to consume the full range of
available fruits (soft and hard). In terms of morphology, performance
(bite force) appears to play an important role in niche partitioning
among bat species, however, very few studies have confirmed these
relationships using functional cranial traits. 2. Here, we analyzed
craniodental traits and their relationship to the bite force in 308
specimens distributed in seven species of stenodermatine bats with two
foraging types: nomadic and sedentary frugivorous bats. We evaluated 19
functional traits of the skull and jaw related to feeding and bite force
in live animals by correcting bite force with body size. We used a GLM
model and post hoc tests to determine possible relationships and
differences between cranial traits, species, and sex. 3. The results
showed that there is significant interspecific variation between
stenodermatines that are nomadic and sedentary. The greatest variation
in bite force within species was explained by the mandibular toothrow
length (MANDL) between sexes, which was greater in females. The larger
species of Artibeus, together with Platyrrhinus helleri, Uroderma
convexum and Sturnira giannae, which have a greater length of the skull,
condylo-incisor, condylo-canine, mandibular toothrow and height of the
coronoid, exhibit greater bite force. By contrast, the smaller species
A. anderseni and A. phaeotis have short skulls and the lowest values of
bite force, which suggests that the size of the skull confers a
biomechanical advantage. 4. Our results highlight the usefulness of
analyzing functional traits related to feeding to establish the
performance of bats in terms of the bite force.