Website: http://www.science.mcmaster.ca/~sigal/index.html

Research involves

Studying social behaviour from both evolutionary and mechanistic perspectives, using cichlid fish as model organisms.

Research relevance

The research is producing a more comprehensive understanding of the evolution of social behaviour as well as of the roles that sex and status play in sculpting the brain and complex behaviour.

Understanding Conflict and Cooperation

Understanding what factors lead to conflict and cooperation in social groups has been a major challenge in evolutionary biology. Just how does social experience and behaviour influence an individual's physiology-from neural anatomy to gene expression?

Sigal Balshine, Canada Research Chair in Aquatic Behavioural Ecology, uses a social species of fish-Neolamprologus pulcher from Lake Tanganyika-to find the answer. She studies the species to learn how complex social behaviours (social aggression, subordination and cooperation) influence the brain and general physiology, and to compare the effects between males and females.

The fish exist in two states: as subordinate helpers and as dominant breeders. Subordinate helpers assist breeding pairs in caring for young, as well as in defence and maintenance of their territory.

To help answer the "big" question, Balshine focuses on specific questions related to the fish such as: How do social rank and sex influence the degree of cooperative versus conflict behaviour? How does variation in social experience (degree of conflict and cooperation) affect levels of sex hormones, cortisol, body condition, and reproductive investment? Is there a difference, in categories such as gross brain morphology, neuropeptide concentrations or gene expression, between males and females? Between dominant and subordinate fish? And how does social experience influence brain anatomy?

Building on previous research, Balshine is testing new ideas concerning the influence of social experience from the molecular/cellular level to physiology, anatomy and behaviour. Her research is pioneering work, as she is the first to examine the influence of cooperation and conflict on the brain, behaviour and physiology in both males and females. And, since she is focusing on a small social fish, she is able to unravel some of the mechanisms responsible for cooperative breeding-something not practical for researchers working with most other social vertebrates.