The mechanisms and function of social recognition in the cooperatively breeding Southern pied babbler, Turdoides bicolor

For group-living species, where the same individuals interact repeatedly, recognising conspecifics and remembering the outcomes of previous encounters may be critical to regulating group dynamics. In all social species, recognition potentially affects individual decisions about mate choice, dispersal, and inter and intra-group interactions. Recognition may be even more important in cooperative species, where cooperation is often predicated on the ability to detect kin, and where stable cooperation may require the capacity to monitor contributions by collaborators. However, we currently know very little about how cooperative species perceive their social environment. Thus, studies of social recognition are of extreme relevance for understanding how cooperation is maintained. Understanding the mechanisms of social recognition, its development, and its limitations facilitates our understanding of the social interactions we observe within populations, and the life history strategies we see. In this thesis I investigate the occurrence, mechanism, and function of social recognition in the highly cooperative Southern pied babbler, Turdoides bicolor. I show that: a) individuals use vocalisations to signal their identity, b)these signals are perceived and discriminated by receivers, both at the level of individual and kin and c) kin are recognised through prior association, but fail to discriminate after years of separation. Finally, I demonstrate the importance of recognition on social behaviour by revealing the influence it has on territorial defence and subordinate dispersal strategies. These findings represent a comprehensive example of the occurrence, development and mechanisms of social recognition, and demonstrate its use and limitations in mediating social interactions.