Marketing

Context (archaeology)

Character displacement

Habitat

Ecology

Biology

Diversity (politics)

Trait

Extinction (optical mineralogy)

Computer science

Community

Anthropology

Business

Diversification (marketing strategy)

Evolutionary biology

Paleontology

Competition (biology)

Sympatry

Sociology

Programming language

Coexistence theory

Host (biology)

Evolutionary ecology

Ecosystem

Ecology Letters

Biological diversity depends on the interplay between evolutionary diversification and ecological mechanisms allowing species to coexist. Current research increasingly integrates ecology and evolution over a range of timescales, but our common conceptual framework for understanding species coexistence requires better incorporation of evolutionary processes. Here, we focus on the idea of evolutionarily stable communities ( ESC s), which are theoretical endpoints of evolution in a community context. We use ESC s as a unifying framework to highlight some important but under‐appreciated theoretical results, and we review empirical research relevant to these theoretical predictions. We explain how, in addition to generating diversity, evolution can also limit diversity by reducing the effectiveness of coexistence mechanisms. The coevolving traits of competing species may either diverge or converge, depending on whether the number of species in the community is low (undersaturated) or high (oversaturated) relative to the ESC . Competition in oversaturated communities can lead to extinction or neutrally coexisting, ecologically equivalent species. It is critical to consider trait evolution when investigating fundamental ecological questions like the strength of different coexistence mechanisms, the feasibility of ecologically equivalent species, and the interpretation of different patterns of trait dispersion.

Evolutionarily stable communities: a framework for understanding the role of trait evolution in the maintenance of diversity