Meeting Abstract
Studies of sexual selection in vertebrates have focused on visual and auditory signals; however, olfactory cues can also effectively communicate an individual’s condition, particularly in mammals. Bats are excellent subjects in which to study the evolution of olfactory signals because many species are nocturnal, live in social groups, and do not rely on visual cues. We investigated a possibly sexually selected trait in fringe-lipped bats (Trachops cirrhosus). Adult male T. cirrhosus produce a previously undescribed odorous orange crust on their forearms. We conducted behavioral observations of reproductive and non-reproductive males in captivity and at natural roosts to determine how this crust is produced. We found that the crust is produced through complex, stereotypic behaviors only observed in reproductively active male T. cirrhosus. We also investigated whether the crust is correlated with body condition (body mass/forearm length) to determine its potential as a signal of male quality. We found that males with a crust had a significantly higher body condition than males with no crust. This study aids our understanding of the evolution of chemical traits under sexual selection. Given that the majority of animals do not primarily rely on visual cues, further study of chemically/olfactory-based systems are necessary to understand the dynamics of sexual selection and sexual signaling.
