S9-5 Wed Jan 6 14:00 – 02:30 Androgenic modulation of multimodal signal structure in foot-flagging frogs Mangiamele, LA; Smith College lmangiamele@smith.edu
Multimodal communication requires coordination of multiple signaling systems. Yet, how multiple signaling traits arise, interact, and share (or do not share) underlying mechanisms is not well understood. In the frog Staurois parvus, visual, vocal, and gestural signals are used for sexual communication in a noisy streamside environment. The recent evolution of “foot flagging” – a gestural signal involving extension and backward rotation of a hind leg – is associated with increased sensitivity to androgenic hormones in the main muscles controlling limb movement, similar to that found in the larynx of vocalizing frogs. We therefore hypothesized that multiple male signals would be androgen dependent in S. parvus. However, antagonism of both central and peripheral androgen receptors (ARs), or peripheral ARs alone, inhibits foot flagging but it does not affect vocalization. Further, antagonism of ARs also decreases the number of transitions between unique display components in a multimodal signaling bout. Together, these results suggest that androgenic action may play a role in overall mating display architecture or signaling strategy, possibly underlying the ability to switch signaling modalities in different environmental or social contexts.