In a genetic study in 2011, researchers found evidence, in DNA samples taken from strands of Aboriginal people's hair, that the ancestors of the Aboriginal population split off from the ancestors of the European and Asian populations between 65,000 and 75,000 years ago—roughly 24,000 years before the European and Asian populations split off from each other. These Aboriginal ancestors migrated into South Asia and then into Australia, where they stayed, with the result that, outside of Africa, the Aboriginal peoples have occupied the same territory continuously longer than any other human populations. These findings suggest that modern Aboriginal peoples are the direct descendants of migrants who left Africa up to 75,000 years ago.
This finding is supported by earlier archaeological finds of human remains near Lake Mungo that date to 45,000 years ago. The same genetic study of 2011 found evidence that Aboriginal peoples carry some of the genes associated with the Denisovan (a species of human related to but distinct from Neanderthals) peoples of Asia; the study suggests that there is an increase in allele sharing between the Denisovans and the Aboriginal Australians genome compared to other Eurasians and Africans. Examining DNA from a finger bone excavated in Siberia, researchers concluded that the Denisovans migrated from Siberia to tropical parts of Asia and that they interbred with modern humans in South-East Asia 44,000 years ago before Australia separated from Papua New Guinea.
They contributed DNA to Aboriginal Australians along with present-day New Guineans and an indigenous tribe in the Philippines known as Mamanwa. This study makes Aboriginal Australians one of the oldest living populations in the world and possibly the oldest outside of Africa, confirming they may also have the oldest continuous culture on the planet. The Papuans have more sharing alleles than Aboriginal peoples. The data suggest that modern and archaic humans interbred in Asia before the migration to Australia.
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