Drivers of Diversity

Abstract

Ecology![Figure][1] CREDIT: ISTOCKPHOTO Large-scale biogeographic patterns of species diversity are generally attributed to the effects of regional climate, climatic history, and other physical factors such as topography. Greve et al. now report a case where continental-scale diversity patterns appear to also be influenced by biotic factors. In Africa, the diversity of acacia trees reaches its highest levels in East Africa and the Limpopo Basin, and the species richness of browsing herbivores (herbivores that use acacias as a food source) is the best explanatory driver of this pattern. The mechanism behind this association remains uncertain; however, one possibility is that decreased fitness and decreased competition of trees under heavier pressure from browsers could lead to greater opportunities for the coexistence of multiple tree species. If consumer diversity has indeed contributed to acacia diversity, the conservation and retention of large herbivores in the African landscape may ultimately be important to the persistence of a diverse tree community. J. Ecol. 100 , 10.1111/j.1365-2745.2012.01994.x (2012). [1]: pending:yes