Over generations of darkness, the subterranean fish lost the huge round eyes of their surface dwelling cousins, and the silvery pigments in their skin. They became Mexican blind cavefish.

The Mexican tetra fish that lives in the rivers of Northern Mexico can heal its heart, while its cave-dwelling relative cannot A fish that can repair its heart may hold clues for future treatments ...

Most people never get to see these fish, but they’re important: Their health reflects the health ... San Antonio Zoo’s Department of Conservation and Research houses some Mexican blindcats in a ...

To demonstrate this, they give the example of the Mexican tetra fish Astyanax mexicanus. Some populations of A. mexicanus are blind cave fish that live in darkness. Other, genetically distinct ...