Abstracts (first author)
Co-evolutionary branching of dispersal and sociality in structured populations
Dispersal has antagonistic effects for the evolution of altruism, cooperation and social behavior. On one hand, dispersal of individuals from their native patches decreases relatedness between locally interacting individuals, and thus disfavors the evolution of social traits. On the other hand, dispersal reduces local competition among kin, thereby favoring cooperation. It is traditionally thought that these two antagonistic effects balance, and as a consequence, an intermediate level of dispersion and sociality evolves. However, recent numerical experiments have suggested that when social traits and dispersal evolve together, evolutionary branching may take place, leading to the stable coexistence of social and asocial individuals with different dispersal strategies. In order to clarify the effects of dispersal on the evolution of cooperation, we developed analytical tools to study the evolution of multiple phenotypic traits in structured populations. By tracking changes in the phenotypic distribution in a population over time, we are able to explicitly predict the conditions that lead to evolutionary branching, and thus the coexistence of different dispersal and cooperating strategies. More generally, our method can be applied to study the emergence of highly differentiated life histories in structured populations.