From Metapopulation to Metacommunity and the Complications of Community Structure

The metacommunity, as it evolved from Levins metapopulation, provides a framework to consider the spatial organization of species interactions. Arguably the most fundamental feature of metapopu-lations and metacommunities are that demes are connected via migration. An important result from Levins metapopulation work--that increasing migration lowers regional extinction probability--is often incorporated into conceptions of metacommunities. We first use a toy model to show how this result from Levins metapopulation does not necessarily hold when considering community interactions in a metacommunity context. We also report results from a metacommunity field experiment conducted with a tropical terrestrial leaf litter community and show that migration induces the extinction of predators in the metacommunity. Our result corroborates the findings of a prior metacommunity experiment in a temperate terrestrial leaf litter community. The concordance between these experiments even with vastly different communities highlights the importance of considering trophic and non-trophic community structure to understand metacommunity dynamics.