The evolution of cichlid fish. (a) A phylogenetic tree adapted with permission from  indicates the origin of Lake Malawi and Lake Victoria cichlids from a single lineage of Lake Tanganyika cichlids; the bracket indicates the Lake Tanganyika and riverine cichlids. MYA, millions of years ago; numbers of species are indicated in parentheses; all species shown are cichlids. (b) A single lineage from the diverse cichlid species of Lake Tanganyika (left) recapitulates a diverse group of cichlid species in Lake Malawi (right) from a single lineage. Many of the Lake Malawi cichlids evolved to fill similar niches to more distantly related species in Lake Tanganyika, and species in similar niches have a surprisingly similar appearance (reproduced from  with permission from Roberto Osti).