Grant: Discovery Grants Program - Individual

In many species, humans included, the social environment influences physiology, behavior, and even evolution. The study of the mechanistic basis of social behaviour in the natural sciences, however, lacks a tractable experimental model system that captures the full range of neural, physiological and behavioural processes that mediate the complex interplay among individuals. For the past decade my students and I have been studying and experimentally manipulating social behaviour in a gregarious songbird: the brown-headed cowbird. We are able to experimentally manipulate social contexts of groups of birds living in large outdoor aviaries and now we are also able to control individuals' social proclivities experimentally by conducting neural manipulations on individuals and then studying them as they live, interact, and breed in social groups. The work in this proposal uses this paradigm (manipulating individuals' social characteristics and testing them as they live in large groups) to examine how neural mechanisms create behavioural phenotypes, how those individual characteristics affect social networks, and, in turn, how social networks change individuals' behavioural phenotypes and even their brains. Female subjects with neural lesions will be introduced into large outdoor aviaries, where subjects can live and breed in complex social environments. The manipulated females will sometimes serve as subjects for experiments (for example, to test their mating patterns, their reproductive output, and the health and viability of their young) but sometimes they will serve as the social environment, creating the culture in which other individuals develop (for example, interacting with juvenile male and juvenile female cowbirds, and thus influencing the juveniles' learning contingencies for song, song preferences and social skills. Taken together, this work will establish a new paradigm for studying the brain mechanisms that influence sociality and conversely, the social features that shape brain circuits. It will provide an integrated investigation into the mechanistic basis and the evolutionary function of social behaviour.