It’s all in the genes. Traces of genetic code from two ancestral species of human have been found in present-day Melanesian people.
Molecular anthropologist Dr. Andrew Merriwether from Binghampton University, and an international team of researchers, compared DNA from Neandertal and Denisovan fossils with blood samples taken from communities living today in the Bismarck Archipelago in Papua New Guinea. The results show “substantial amounts of Neanderthal and Denisovan DNA” in the modern population, the scientists report in the journal Science.
Previous studies have indicated that Neandertals (Homo neanderthalensis) and modern humans (Homo sapiens) from outside the African continent share a 2 percent genetic overlap, suggesting that interbreeding occurred between the two species for thousands of years. But according to Merriwether’s team, it was surprising to find Neanderthal influence in Oceania. It’s quite a trek from Western Eurasia, where most of the interaction between the species is thought to have happened between 47,000 and 65,000 years ago.
Also, little was previously known about the genetic influence of Denisovans — a recently-discovered human ancestor identified from remains found in the Denisova Cave in southern Siberia. Merriwether’s research shows that present-day Melanesians share between 1.9 and 3.4 percent of their genetic code with these enigmatic ancestors.
Source: B. Vernot et al., Science 10.1126/science.aad9416 (2016).