Question: What is the defining feature of ring species? Need Assignment Help? A ring species is created when a cline wraps around into a circle, leading to divergent populations that can no longer interbreed. In a ring species, multiple coexisting species create a circular arrangement around a geographic structure. Ring species arise when two populations undergo speciation but can still interbreed. Ring species emerge when populations move apart along a ring-shaped cline until they are no longer in contact.