Ecological constraints predict the spatial structure of biodiversity

Conservation strategies depend on a basic understanding of how communities are spatially structured.  The Maximum Entropy Theory of Ecology (METE) proposes that communities may be in the most likely spatial distribution given two ecological constraints: total number of species and total number of individuals.  We developed and tested the spatial predictions of METE using the species-area and distance-decay relationships across a global forest dataset. The METE predictions were extremely accurate for the species-area relationship, but METE generally predicted steeper patterns of distance-decay than observed empirically.  Our results demonstrate that ecological constraints can inform predictions of spatial community structure.