Cavefish Study Supports Controversial Evolutionary Mechanism

摘要

To the classic case studies of evolution, such as Darwin's finches and the peppered moth, a small group of researchers would now add the Mexican tetra. This small, freshwater fish is mostly found as a drably colored inhabitant of creeks and rivers. But at least a half dozen times, populations have taken up residence in caves, where they have been transformed. They remain the same species, but are now eyeless and nearly albino.