Abstract
Natural hybridization is a widespread phenomenon, detected among clades of fungi, plants, and animals. The potential outcomes of genetic exchange include adaptive trait evolution, speciation, and even the radiation of entire species complexes. Not only does natural hybridization have the potential to affect evolutionary processes, it often does so very rapidly. Indeed, adaptations can be transferred in only a handful of hybrid generations. Likewise, entire species assemblages may arise from a hybrid swarm over the space of a few thousand years. This chapter tests these conclusions with examples from a diverse array of fungal, botanical, and zoological examples. Each example illustrates the potential for natural hybridization to provide the genetic and phenotypic variation necessary for rapid, adaptive, diversifying evolution.