Some cichlid fish see red better while others only have eyes for blue. This difference in vision, observed in fish in an African lake, could be pushing red-bodied cichlids to branch off from their blue-bodied brethren and to form a new species.
By looking at the DNA of fish from both groups, Okada’s team showed that each has accumulated genetic changes not shared by the other, which suggests that the two groups aren’t interbreeding, Okada and his colleagues report in the Oct. 2 Nature. They also showed in experimental studies that female fish from the red-light group preferred red-colored males, and vice versa. Taken together, the results suggest that changes in the fish’s vision could be starting to split the fish into two species.
It would have been nice to know which species they were discussing in the article.....
