A comprehensive framework for global patterns in biodiversity

Robert E. Ricklefs Department of Biology, University of Missouri-St Louis, 8001 Natural Bridge Road, St Louis, MO 63121–4499, USA E-mail: [email protected] Abstract The present study proposes to reconcile the different spatial and temporal scales of regional species production and local constraint on species richness. Although interactions between populations rapidly achieve equilibrium and limit membership in ecological communities locally, these interactions occur over heterogeneous environments within large regions, where the populations of species are stably regulated through competition and habitat selection. Consequently, exclusion of species from a region depends on long-term regional-scale environmental change or evolutionary change among interacting populations, bringing species production and extinction onto the same scale and establishing a link between local and regional processes.