Ecology: Diversity breeds complementarity.

Abstract

Evolutionary and ecosystem processes have long been treated as distinct. The finding that interactions among plant species cause rapid evolutionary changes that affect ecosystem function suggests that it is time for unification. See Letter p.108 More diverse plant communities are often more stable and productive, an effect which tends to increase through time. In this paper, Debra Zuppinger-Dingley et al. investigate the role of evolution in this ecological phenomenon. They assemble new ecological communities using plants — grasses, herbs and legumes — with different recent evolutionary histories, grown in either mixed-species communities or monocultures. Ecosystem functioning and morphological trait diversity were greater in communities of mixture-grown than monoculture-grown plants, suggesting that biodiversity effects in natural communities strengthen as populations adapt to their biotic environment. The finding that small-scale evolution is important to ecological relationships brings together these different perspectives on species coexistence in natural communities.