Generally, it is thought that new species are formed when two populations become physically isolated from each other and, over time, become so different that they can no longer interbreed. New research published in the journal Proceedings of the National Academy of Sciences, however, suggests species can also form within populations that are not geographically separated—a phenomenon called “sympatric” speciation.
The researchers found evidence that a population of spiny mice (genus Acomys) is diverging into two species in different slopes of a canyon in Israel. Although there is no physical barrier between them, the canyon’s slopes vary dramatically; one is hot and dry while the other is cool, humid, and forested. The scientists call the area “Evolution Canyon” because they believe it holds many examples of sympatric speciation.
The finding adds fuel to the debate among evolutionary biologists over the prevalence of sympatric speciation in nature—a debate that has been ongoing since Darwin’s time.
Climate change is likely to cause ecosystems to experience shifts that can affect species’ ranges and distribution. Learn more about the ecological impacts of climate change in the Koshland Science Museum’s Earth Lab exhibit or the National Academies’ online resource, Ecological Impacts of Climate Change.