Fossils from Africa exhibit features of both modern humans and archaic species — possible evidence for interbreeding. However, finding a genetic legacy of such encounters has been difficult because of a lack of ancient human DNA from Africa.

Michael Hammer at the University of Arizona in Tucson and his team analysed the entire genomes of seven individuals from two contemporary Western African Pygmy groups. The researchers identified 265 regions of the Pygmy genomes that may have been acquired through ancient interbreeding with other species, events that could have happened as recently as 9,000 years ago.

Genome Res. http://doi.org/bct3 (2016)