22.11 Wednesday, Jan. 4 Cranial Morphology, Feeding Performance and Diversification in New World Leaf-Nosed Bats DUMONT, E.R.*; DAVALOS, L.M.; GOLDBERG, A.; SANTANA, S.E.; REX, K.; VOIGT, C.C.; Univ. of Massachusetts, Amherst; Stony Brook University; Stony Brook University; Univ. of California, Los Angeles; Leibniz Institute for Zoo and Wildlife Research ; Leibniz Institute for Zoo and Wildlife Research firstname.lastname@example.org
Ecological opportunity coupled with innovation in morphology is thought to open doors to new adaptive zones and promote species diversification, although in practice it has proven difficult to demonstrate this sequence. Among mammals, New World leaf-nosed bats (Phyllostomidae) are a good system in which to investigate this process because of their tremendous diversity in cranial morphology and diet. There are phyllostomid species that feed on insects, small vertebrates, nectar, blood and fruit. Moreover, several studies have suggested that the transition to frugivory provided an ecological opportunity that promoted diversification. Here we link the evolution of cranial morphology, biting performance, diet and species diversification rates in phyllostomid bats. We found that that our measure of cranial morphology is a good predictor of biting performance, and that diet and cranial morphology evolved together. We found a significant shift in speciation rate at the base of the most frugivous clade (Stenodermatinae). Following this increase in speciation rate, the rate of morphological evolution slowed while the rate of evolution in diet increased. This pattern suggests that cranial morphology stabilized once it resulted in a certain level of biting performance, and then niches within the new adaptive zone of frugivory were filled rapidly. The tree-wide speciation rate increased linearly with a increased frugivory, and was highest at both morphological extremes. These results suggest a central role for a novel stenodermatine skull phenotype and performance in the evolution of frugivory and increase in speciation within phyllostomids.