The ecology and evolution of food-chain length in metacommunities
Vendredi 10 Novembre - 11:00 - Sophia Antipolis - Inra PACA - Salle A010
Metapopulation dynamics, i.e. the dynamics of population growth, extinction and re-colonization at a large spatial scale, has been a useful concept to explain signatures of genetic differentiation or to understand the persistence of species in environments submitted to random perturbations. However, the ecological consequences of adaptive evolutionary changes in metapopulations or metacommunities, or on the contrary the evolutionary changes induced by environmental modifications in habitat patches, have garnered less interest from both theoreticians and empiricists. Here, I will present some recent results that have emerged from applying (i) patch-occupancy metacommunity models to the problem of food chain length and (ii) trait evolution dynamics in these models. I will show that (i) metacommunity dynamics can provide a strong constraint on the length of food chains, (ii) the interaction of processes such as top-down control of species colonization rates and species extinction rates in patches can affect occupancy and food chain length in a non-intuitive way, and, (iii) when species colonization rates are allowed to evolve, the combination of ecological constraints on suitable habitat and the competition-colonization trade-off leads to eco-evolutionary feedbacks, with consequences on metacommunity occupancy, species colonization rates and food chain length. I will discuss some of the testable predictions emerging from these models in the context of recent experimental findings on metacommunity dynamics.