Kin Selection in Plants

Kin selection may act directly on individuals expressing a particular trait as well as indirectly through the trait's effect on the fitness of their relatives. This insight has fundamentally transformed our understanding of the evolution of animal behavior—especially social behavior—but it is relevant to any organism in which individuals interact with their relatives, including plants. We here explore how and when kin selection might occur in plants, both through reducing the effects of competition among kin and through promoting the improved performance of kin. We survey plant traits likely to be affected by kin selection, including sex allocation, ovule number, dispersal, seed dormancy, and traits affecting competition. We point to opportunities for future research on kin selection in plants, explain what such research needs to accomplish, and identify limits on the action of kin selection. To conclude, we discuss approaches for detecting kin selection in nature.