Event:

Learned acoustic signals in group-living animals serve diverse critical functions including locating and identifying mates and members of the social group, antipredator strategies and group coordination. This is particularly relevant for social animals with fission-fusion dynamics, where vocal signatures of group and individual identity are critical as groups associate and dissociate. Parrots are an excellent system to study these phenomena, being open-ended vocal learners with fission-fusion social structures which are amenable to studies in captivity. In multiple species, vocalizations signal group identity and contact calls converge by social learning when groups come into contact. I will first discuss earlier studies from my lab on budgerigars (Melopsittacus undulatus), demonstrating that their complex warble songs are both individually variable and linked to steps in their courtship display, and also contain signatures of group identity that converge after groups come into contact. These studies suggest links between vocal similarity and social hierarchies. I will next discuss how we tested these links in captive colonies of two species: budgerigars and Rosy-faced Lovebirds (Agapornis roseicollis). First, we filmed the colonies to record behavioral interactions and construct inter-individual social networks. Next, we recorded males in an acoustically isolated chamber to obtain clean recordings of both vocal sequences and contact calls. We quantified patterns in acoustic similarity both at the level of individual contact call-like notes (spectral similarity) and at the level of vocal sequences (syntactic similarity). Our results indicate that both species exhibit stable dominance hierarchies, with individual signatures in both contact calls and the syntax of vocal sequences. Further analyses indicate that dyadic interactions and network structure are important determinants of vocal similarity between individuals. I will discuss these results and their implications for vocal learning in group-living animals.