Multilevel Selection and the Evolution of Predatory Restraint

Individual selection favors that predator which can most efficiently turn its prey into increased reproductive capacity. But any species that becomes too successful in this game sows the seed of its own demise; for its progeny may be delivered into an environment where prey populations are depleted, and starvation a danger. From this danger derives a compensatory evolutionary pull toward moderation. The latter effect derives from a cost that is shared generally by the community that claims a common prey population. A widely accepted argument from classical evolutionary theory holds that the selective force of such group effects is likely to be weak and slow-acting compared to the efficiency of individual selection. We offer a numerical simulation in defiance of this wisdom, demonstrating how under general assumptions and a wide range of parameter values, predatory restraint may evolve as a group adaptation.