Breaking Barriers: Causes, Consequences, and Experimental Utility of Human-Mediated Hybridization

Hybridization between naturally co-occurring species that normally do not interbreed is being documented following anthropogenic habitat modifications for an increasing number of taxa. Here, we evaluate the mechanisms by which disturbance promotes hybridization and highlight the utility of human-caused hybridization for understanding evolution. Monitoring hybridization dynamics before, and following, disturbance over multiple timescales offers a unique opportunity to understand how disturbances alter species interactions and to pinpoint the mechanisms that cause species barriers to fail. Identifying the conditions promoting hybridization in disturbed habitats, the generality of these conditions across taxa, and the taxa most affected by human-mediated change is critical for furthering our understanding of human impacts on evolution and for informing management.