Lake Victoria, together with its satellite lakes, harbours roughly 200 endemic forms
of cichlid fishes that are classified as 'haplochromines' and yet the lake system is less
than a million years old. This 'flock' has attracted attention because of the possibility
that it evolved within the lake from one ancestral species and that biologists are thus
presented with a case of explosive evolution. Within the past decade, however, morphology
has increasingly emphasized the view that the flock may be polyphyletic. We sequenced
up to 803 base pairs of mitochondrial DNA from 14 representative Victorian species and
23 additional African species. The flock seems to be monophyletic, and is more akin to
that from Lake Malawi than to species from Lake Tanganyika; in addition, it contains
less genetic variation than does the human species, and there is virtually no sharing of
mitochondrial DNA types among species. These results confirm that the founding event
was recent.