The human past of Southeast Asia – the territory now occupied by Burma, the Philippines, Cambodia, Indonesia, Thailand, and Vietnam, among other countries – has been the subject of debate among anthropologists for decades. Where does the current population come from? When and how did agriculture arise there? Was it invented on their own by the indigenous people of the Hoabinhiam (inhabitants of those lands for about 44,000 years) or was it imported by Chinese farmers?
In order to put an end to the discussions once and for all, an international team of specialists led by Professor Eske Willersev, who works at the universities of Cambridge and Copenhagen, has just completed what seems to be the definitive study on the matter. And the verdict is that modern South Asians come from at least four different prehistoric peoples .
The scientists base their hypotheses on analyzing DNA extracted from skeletons found in Malaysia, Thailand, the Philippines, Vietnam, Indonesia, Laos and Japan, up to 8,000 years old . Before, they had only managed to sequence genetic material from up to 4,000 years ago. The new samples came from several hoabinhiam and also the skeleton of an individual linked to the Jomon culture, which developed in the Japanese archipelago from about 16,000 years ago until the Neolithic period. In total, the scientists had at their disposal 26 genomes of ancient humans , which they compared with those of the current inhabitants of the region.
An unsuspected genetic wealth
The results, published in the journal Science , have surprised the scientific community, who did not foresee the underlying genetic richness in the roots of the modern inhabitants of Southeast Asia. First, the Jomon and the Hoabinhiam – geographically far apart – have been found to be genetically related, already suggesting astonishing mobility. And furthermore, both Hoabinhiam hunter-gatherers and farming peoples contributed to the area’s gene pool, with later contributions from other migrations to the islands of Southeast Asia and Vietnam during the Bronze Age.
“This is a much more complex model, by far, than the one we used previously,” sums up Fernando Racimo, associate professor at the Museum of Natural History at the University of Copenhagen and one of the study participants.
Apart from the merit of radically changing the perspective of paleontropological research in the region, the new work has an added merit, since finding bone remains with DNA that can be sequenced is a challenge in Southeast Asia , whose humid climate does not exactly help that the bones arrive in good condition to this day.
Photo: skull of an ancient hoabinhiam found at the Gua Cha site in Malaysia. Credit: Fabio Lahr.
More information: Eske Willersev, Hugh McColl, Fernando Racimo, Lasse Vinner, Fabrice Demeter, J. Víctor Moreno-Mayar et al. “The prehistoric peopling of Southeast Asia”. Science (2018). DOI: 10.1126 / science.aat3628
