Eco-evolutionary dynamics in metacommunities: ecological inheritance, helping within- and harming between-species

Abstract

Understanding selection on traits affecting intra-and inter-specific interactions in meta-communities subject to stochastic demography is a long-standing problem in ecology and evolution. The problem is that eco-evolutionary dynamics are too complicated to make analytical investigations tractable.We here circumvent this problem by approximating the selection gradient on a quantitative trait that influences local community dynamics, assuming that such dynamics are deterministic but taking into account kin selection effects arising from local demographic stochasticity. Selection on a trait is shown to depend on how an individual expressing a change in trait value changes: (1) its own fitness and that of its relatives living in the present; and (2) the fitness of all its relatives living in the future through modifications of local ecological conditions. The latter effects capture feedbacks between ecology and evolution, which impact downstream generations ("ecological inheritance"), and take the form of press-perturbations of community ecology.As an illustration, we analyze the evolution of altruism within and spite between species. We show that altruism within species is more likely when competition is for material resources than for space, and that spite between species can readily evolve to alleviate local competition for future relatives. More broadly, our approximate selection gradient opens an avenue to analyze a variety of eco-evolutionary questions in meta-communities, from selection on mutualism to prey-predator coevolution.