Researchers have sequenced the genome of a man who was an Aboriginal Australian and used that to show that modern day Aboriginal Australians are the direct descendants of the first people who arrived on the continent some 50,000 years ago and that those ancestors left Africa earlier than their European and Asian counterparts.
Although there is good archaeological evidence that shows humans in Australia around 50,000 years ago, this genome study could rewrite the story of their journey there. The study provides evidence that Aboriginal Australians are descendants of the earliest modern explorers and left Africa around 24,000 years before their Asian and European counterparts, which is contrary to the previous and most widely accepted theory that all modern humans derive from a single out-of-Africa migration wave into Europe, Asia, and Australia.
The study derived from a lock of hair donated to a British anthropologist by an Aboriginal man from the Goldfields region of Western Australia in the early 20th century. One hundred years later, researchers have isolated DNA from this same hair, using it to explore the genetics of the first Australians and to provide insights into how humans first dispersed across the globe.
Credit: Voice: Sheena Lauersen. Illustration: Science/AAAS, Sofia Olsen. Stills: Mikal Schlosser, Timothy P. Topper. Camera: Kristoffer Aabo, Henrik Prætorius. Production: Henrik Prætorius.
By sequencing the genome, which was shown to have no genetic input from modern European Australians, the researchers demonstrated that Aboriginal Australians descend directly from an early human expansion into Asia that took place some 70,000 years ago, at least 24,000 years before the population movements that gave rise to present-day Europeans and Asians.
Professor Eske Willerslev from the University of Copenhagen, who led the study, said, "While the ancestors of Europeans and Asians were sitting somewhere in Africa or the Middle East, yet to explore their world further, the ancestors of Aboriginal Australians spread rapidly; the first modern humans traversing unknown territory in Asia and finally crossing the sea into Australia. It was a truly amazing journey that must have demanded exceptional survival skills and bravery."
Dr Francois Balloux, MRC Centre for Outbreak, Analysis and Modelling, Imperial College London, led the UK team, and said, "Thanks to tremendous progress in sequencing technologies it is much easier to compare genomes of individual people, including those from geographically distinct populations. And by doing this you can learn a lot about when and via what route they came to be where they are today. In this way, the science of genomics makes a unique contribution to our understanding of when and how humans colonised the world."
Genomics study published in Science.