On the Origin of Species by Natural and Sexual Selection

Abstract

Local Selection of Magic Traits Ecological interactions can favor specialization, and sexual selection can induce reproductive isolation; however, these processes are insufficient by themselves to create new species. They must act in concert and on the same set of genes. Van Doorn et al. (p. 1704 , published online 26 November; see the Perspective by Mank ) present a theoretical model that shows that within a larger population the evolution of mating preferences will favor sexual ornaments that indicate the degree of adaptation to the local ecological conditions, for example, the abundant song of a male bird that can obtain food easily because it has the right bill size for the seeds in that locale. Once mate choice evolves on the basis of a signal of local adaptation, natural and sexual selection will mutually enforce each other, ultimately leading to speciation.