Evolution of Sociality

For an extended period, scientists in both biology and sociology have endeavored to understand the influence of individual similarity on inter-individual interactions (with biology primarily focusing on mating and sociology on cooperation or game-theoretic behavior). Existing studies indicate that homophily tends to evolve under a wide variety of conditions. In this paper, we extend previous models to propose a new framework for examining which individual preferences are favored by natural selection in populations with multiple observable phenotypes. The payoffs to interactions depend on whether individuals share the same or different phenotypes. Each individual possesses a binary preference combination that represents their strategy, where the two preferences respectively govern the likelihood of interaction with individuals of the same phenotype (homophily) or with those of a different phenotype (heterophily). We derive the conditions under which the population tends to evolve more homophilic preferences.