Individuals and the Variation Needed for High Species Diversity in Forest Trees

Abstract

Difference, Not Diversity In tropical forests, as in the ocean plankton, thousands of species may compete for the same resources. How they succeed in coexisting remains one of the central paradoxes in the study of biodiversity. Theory shows that coexisting species must partition the environment, but such partitioning is not obvious. Using data from coexisting forest trees in the southeastern United States, Clark (p. 1129 ) show that individual variation between members of the same species allows them to avoid direct competition: One plant may differ significantly from another in its requirements for light, nutrients, or moisture, yet remain within the general spectrum of features displayed by its conspecifics.