Hortal, J., De Marco Jr, P., Santos, A.M.C. & Diniz-Filho, J.A.F. (2012) Integrating biogeographical processes and local community assembly. Journal of Biogeography, 39, 627–628. doi:10.1111/j.1365-2699.2012.02684.x

The nature of ecological communities has been a longstanding question in ecology since the debate between F.E. Clements and H.A. Gleason (Ricklefs, 2008). While Clements (1936) viewed communities as closed structures that tend to persist through time, Gleason (1926) perceived them as dynamic entities resulting from the mere coincidence of species’ distributions in space and time. Taken to its extreme, the Clementsian view implies that the characteristics and ecological roles performed by the species that form a community determine which new species will be able to establish populations in the locality through either facilitation or competitive displacement (see Clements, 1936). The absence of large-scale processes from Clements’ ideas – which focus exclusively on local interactions – may create the false impression that community processes hardly scale up to geographical patterns. In contrast, Gleason’s view embraces processes acting at multiple scales (from local habitat selection to the species’ macroclimatic requirements), that determine the individualistic response of each species.