Global Correlations in Tropical Tree Species Richness and Abundance Reject Neutrality

Abstract

Forest Diversification The relative role of neutral and deterministic processes in generating species richness in ecological communities (particularly tropical trees) has dominated recent discussions about patterns of diversity and abundance of species. Ricklefs and Renner (p. 464 ) present a test of random diversification and population change by comparing the numbers of individuals and species in plant families between forest plots on different continents that have diversified independently for millions of years. Stochastic theory, based on random events, predicts that there should be no correlation between the regions; however, the data reveal strong, statistically significant correlations. Thus, patterns of diversity appear to be dominated by deterministic processes.