Serial polygyny in the primitively eusocial wasp Ropalidia marginata: implications for the evolution of sociality

Social insects usually live in colonies comprising one or a small number of reproductive individuals and a few or large number of sterile individuals. In termites only, both sexes are represented among the reproductives as well as among the sterile workers. In other social insects, namely ants, bees, and wasps, males do not participate significantly in the social life of colonies, which involves primarily the fertile queens and sterile female workers (Wilson 1971). The haplodiploid genetic system found universally in the Hymenoptera creates an asymmetry in genetic relatedness such that a female is more closely related to her full sister (coefficient of genetic relatedness, r = 0.75) than to her offspring (r = 0.5). This makes inclusive fitness theory (Hamilton, 19640, b) particularly applicable to the evolution of sterile worker castes in the social hymenoptera (Wilson 1971; Hamilton 1972)