Speciation
All of the native drosophilid species in Hawaii have apparently descended from a single ancestral species that colonized the islands, about 20 million years ago. The subsequent adaptive radiation was spurred by a lack of competition and a wide variety of vacant niches. Although it would be possible for a single pregnant female to colonise an island, it is more likely to have been a group from the same species.Carson H.L. 1983. Chromosomal sequences and interisland colonizations in Hawaiian Drosophila. Genetics 103, 465-482.Kaneshiro K.Y. Gillespie R.G. and Carson H.L. 1995. Chromosomes and male genitalia of Hawaiian Drosophila: tools for interpreting phylogeny and geography. In Wagner W.L. & Funk E. (eds) Hawaiian biogeography: evolution on a hot spot archipelago, Smithsonian Institution Press, Washington D.C. 57-71