Traces of DNA from Denisovans, an extinct group of archaic humans from Asia, have been found in modern humans from Papua New Guinea and elsewhere in Melanesia.

Studies have shown that all non-Africans owe about 2% of their ancestry to Neanderthals, but only Melanesians seem to harbour substantial levels of Denisovan DNA as well. To better characterize the Denisovan heritage of modern humans, Joshua Akey at the University of Washington in Seattle, Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and their team sequenced the genomes of 35 people from Melanesia, and analysed the genomes of another 1,496 people from around the world.

They found that the Melanesians derived between 1.9% and 3.4% of their ancestry from Denisovans. Long stretches of the genomes that were devoid of both Denisovan and Neanderthal DNA included genes that are expressed in certain parts of the brain and one, FOXP2, that is involved in speech and language.

Science http://dx.doi.org/10.1126/science.aad9416 (2016)