When Ecology Fails: How Reproductive Interactions Promote Species Coexistence

That species must differ ecologically is often viewed as a fundamental condition for their stable coexistence in biological communities. Yet, recent work has shown that ecologically equivalent species can coexist when reproductive interactions and sexual selection regulate population growth. Here, we review theoretical models and highlight empirical studies supporting a role for reproductive interactions in maintaining species diversity. We place reproductive interactions research within a burgeoning conceptual framework of coexistence theory, identify four key mechanisms in intra- and interspecific interactions within and between sexes, speculate on novel mechanisms, and suggest future research. Given the preponderance of sexual reproduction in nature, our review suggests that this is a neglected path towards explaining species diversity when traditional ecological explanations have failed.

Automated summary

Recent research has shown that ecologically equivalent species can coexist under the regulation of reproductive interactions and sexual selection. Reproductive interactions play a significant role in maintaining species diversity, as highlighted by theoretical models and empirical studies. This neglected pathway towards explaining species diversity offers new insights and future research directions within the conceptual framework of coexistence theory.