Adult Drosophila fruit flies feed on yeasts on the surface of ripe fruits. Female flies lay their eggs inside the fruit and the larvae feed inside the fruit before developing into adults. The tree Morinda citrifolia produces fruits called noni fruits. Noni fruits contain a toxin and are avoided by nearly all Drosophila species, including Drosophila yakuba in mainland Africa. One population of D. yakuba lives on the island of Mayotte off the coast of Africa. The population of D. yakuba on Mayotte has specialised to feed on noni fruit. Flies of this population produce enzymes that give them resistance to the toxin in noni fruits. Adults are able to feed on yeasts on the fruit surface and their eggs and larvae can develop and grow inside the fruit. Scientists have used bioinformatics to estimate that the unique D. yakuba population on Mayotte originated in the last 30000 years.