ABSTRACT
Food sharing is common among foraging bands, but the degree and mode of sharing differ across hunter-gatherer communities, leading to varying degrees of reciprocity and willingness to share. Various factors influence the prevailing sharing norms found in hunter-gatherer societies and lead to a plethora of institutional setups. These factors include the cost of punishment, the benefit of sharing or free-riding or the intrinsic benefit from sharing, in addition to kin selection and reciprocal altruism – and conversely, these factors are determined by the social and natural environment in which foraging bands interact.
To study the impact of these factors, this chapter introduces the reader to evolutionary game theory and covers elementary aspects that are central to the study of social systems, in particular the analysis of dynamical systems and differential equations. This approach is particularly apt for analysing interactions among large numbers of agents. This chapter introduces the replicator equations and the notion of asymptotically / evolutionarily stable equilibria, and studies in particular the social dynamics of one and two-player population games.
Among the concepts discussed are: nodes, repellors and saddle points, eigenvalues, basins of attraction, stable and unstable manifolds, unit simplices, best-responses, and tangential bifurcations.
