The Meta-Community Concept: A framework for large scale community ecology?

The concept of meta-communities was developed in an effort to link community ecology theory at the local level with regional and global models at larger spatial scales. Currently there are two contrasting views of meta-communities. The "patch-dynamics" perspective is based on the idea that similar local habitat patches are colonized by species that interact to produce communities consisting of different species depending on their dispersal abilities. In contrast, the "species-sorting" view assumes that sites differ in their abiotic environment, causing interacting species to sort themselves differently along gradients depending on their competitive abilities at different sites. The first view ignores local population dynamics and therefore allows for non-equilibrial abundances but it ignores intrinsic heterogeneity among local sites. The second view is generally modeled using equilibrium models of local population dynamics but accounts for heterogeneity among sites. Empirical evidence suggests that both of these approaches are useful for understanding patterns in real communities. Thus there is a need for a more synthetic approach. We propose to form a collaborative group to work on such a synthesis. Our goal is to explore what happens when both sets of metacommunity processes occur. We hope to use this synthetic approach to explore their roles in regulating phenomena such as the trophic structure, patterns of diversity and composition along environmental gradients and the role of regional processes such as dispersal in ecosystem processes.