No less than 500 new species of cichlids, brightly coloured perch-like fish, evolved in Lake Victoria (East Africa) over the past 15,000 years -- a record in the animal and plant world. This evolutionary puzzle has now been solved by scientists. They demonstrate for the first time that this rapid evolution was facilitated by earlier hybridization between two distantly related cichlid species from the Upper Nile and Congo drainage systems.

Source: Explosion in species diversity due to hybridization