A novel approach for finding ring species: Look for barriers rather than rings

Abstract

Ring species, in which two different forms coexist in one region while being connected by a long chain of interbreeding populations encircling a geographic barrier, provide clear demonstrations of the evolution of one species into two. Known ring species are rare, but now Monahan et al. propose an intriguing new approach to discovering them: focus first on geography to find potential barriers.See research article http://www.biomedcentral.com/1741-7007/10/20. © 2012 Irwin; licensee BioMed Central Ltd.