Game Theory, Reproductive Skew, and Nepotism

Abstract

Abstract Our understanding of the evolution of cooperative kin groups has been greatly advanced by kin selection models (Hamilton 1964, West-Eberhard 1975) and, more recently, by a melding of such models with game-theoretic models to explain and predict the outcomes of a variety of intragroup conflicts (Trivers&Hare 1976, Gra fen 1979, Emlen 1982, Vehrencamp 1983, Reeve 1991, Reeve&Ratnieks 1993, Reeve&Keller 1995, Mock et al., this volume). In this chapter, I focus on potential conflicts within kin groups over both the partitioning of reproduction and the expres sion of nepotism, the latter conflict arising when resolution of the former leads to reproductive sharing among group members. In particular, I shall argue that new game-theoretic models are needed to shed light on two fundamental problems: (1) the joint evolution of reproductive partitioning and genetic composition of cooperative groups, especially when potential group-joiners have a choice of groups to join or residents have a choice of joiners to accept, and (2) the selective mechanisms underlying the surprising absence of within group nepotism in kin groups, most notably in social insect colonies.