Managing the threats and opportunities afforded by human sociality.

Group living offers humans substantial fitness-enhancing benefits, although it also affords significant fitness-decreasing costs. To enhance these benefits and reduce these costs, individuals use emotional, cognitive, and behavioral mechanisms designed to help them effectively manage the complexities of life in highly interdependent groups. The authors briefly outline their evolutionary, functional analysis of human sociality and summarize accumulating empirical support for various implications derived from this conceptual analysis. In particular, the authors focus on four questions central to intragroup and intergroup relations: (a) How do people manage the need to be selective in their choice of social affiliates? (b) how do people manage the impressions others form of them? (c) how do people manage the threats that fellow group members often