Meeting Abstract
Multimodal communication often evolves in noisy habitats, where selection favors multiple ways to send messages to conspecifics. Multimodal displays are highly dynamic; however, to date most studies have focused on how signaling behavior varies across behavioral contexts and physical environments. We hypothesize that endocrine state also influences the structure of multimodal displays. To test this hypothesis, we recorded the interactions between two male Bornean rock frogs (Staurois parvus) and one female and quantified the behavior of a focal male during aggressive bouts. S. parvus uses an array of vocal and visual signals for male-male competition, the most conspicuous of which is an unusual hind limb gesture known as “foot flagging.” A bout was defined as a period of short intense activity that was initiated by either a foot-flag or a call. Males were treated either with 1) saline, 2) testosterone + vehicle, or 3) testosterone + flutamide, an androgen-receptor blocker. We used R to create kinematic diagrams that mapped the frequency and sequences of the six main behaviors in the males’ multimodal display. Our results show that when flutamide is introduced as an androgen receptor blocker, it decreases the number of bouts that occur. Flutamide also influences display dynamics in S. parvus by decreasing the overall frequency of many behaviors, and reducing the complexity of the entire network of behaviors by increasing repetition.
