WHAT DETERMINES ANIMAL GROUP-SIZE - INSIDER-OUTSIDER CONFLICT AND ITS RESOLUTION

Presents a theory that, by incorporating the evolutionary interests of both insiders and outsiders, generates a more comprehensive set of predictions of group size and provides new insights into the determinants of group size. A key idea of the theory is the evolutionary resolution of the insider-outsider conflict over group size, resulting in a "compromise group size' that can substantially differ from any of those predicted by previously proposed hypotheses. The authors summarize existing group size hypotheses, and clarify their mutual relationships. This leads to an explicit identification of conflict between the insiders and outsiders of a group of related individuals. -from Authors