Linking the evolution of gender variation to floral development

Background and Aims In the present review, I have endeavoured to conduct a joint assessment of the thinking underlying the evolutionary genetics of gender polymorphism and the developmental genetics of gender determination. It is my hope, through highlighting the historical development of ideas in two related but somewhat disparate sets of scientific literature, to encourage a synthetic perspective that integrates the two. Scope An overview is provided of various theories on the evolution of sex polymorphism and examples of evidence that has been brought to bear in support of them. Current knowledge on floral development is summarized, with an emphasis on gender variation. Finally, an attempt is made to integrate the two perspectives with the hope that it will encourage future research at the interface. Conclusions Evolutionary models of gender evolution have, of necessity, posited genetic effects that are relatively simple in their impacts. Emerging insights from developmental genetics have demonstrated that the underlying reality is a more complex matrix of interacting factors. The study of gender variation in plants is poised for significant advance through the integration of these two perspectives. Bringing genomic tools to bear on population-level processes, we may finally develop a comprehensive perspective on the evolution of floral gender.