The Salamander That Forms A Living Ring

The Ensatina salamander is a master of evolution that has spread across California in a giant circle. While populations at each step can mate with their neighbors, the two groups that meet at the end of the chain can no longer interbreed.

This phenomenon is known as a ring species, acting as a perfect living map of speciation. As these salamanders migrated south around the massive Central Valley, they split into two distinct paths that slowly changed over millions of years. By the time they met again at the southern tip, they had become so genetically different that they effectively became two separate species. It is a rare, visible case of evolution unfolding right before our eyes.