How to Become Selfish: Evolution and Adaptation to Self-fertilization in Plants

A major trend in plant evolution is the transition from outcrossing to selfing. This transition has occurred many times independently despite some putative detrimental consequences on the evolutionary potential of individuals. In animal–pollinated flowers, this transition has often been followed by a set of changes in flower characters, sex allocation and life history. In this article, we review the evolutionary history of this transition focusing on the shift from obligate outcrossing to predominant selfing. We discuss the current knowledge on the ecological factors driving selfing evolution and the consequences on the morphology, biogeography and evolution of selfing lineages. This event constitutes an excellent model to study phenotypic evolution in plants, and several studies are starting to shed light on the underlying molecular and evolutionary mechanisms.