Fish Fall Victim to “Pollution Goggles” When It Comes to Mating

At a bar, intoxicated people may fall victim to the notorious “beer goggles” effect. Now, researchers have discovered that in the fish world, pollution can have the same effect as a six-pack of Heineken. Scientists already know that female African cichlids are partially blind, and have evolved into a new species over the past 30 years. The cichlids in Lake Victoria’s polluted waters are vanishing, causing “the largest human-witnessed mass extinction of vertebrates.” And now, pollution is also causing closely-related species of cichlids to interbreed, all because they can't see each other. Color is very important in cichlid mate choice, and normally when the water is clear, red females like red males and blue females like blue males. Because blue appears brighter in shallow water and red is brighter in deep water, the fish tend to stick to their comfort zones. But when the water is murky, they have no ...