Aboriginal Australians descendants of Denisova hominin;Sahul

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. These findings are in concordance with the results of other comparison tests which show a relative increase in allele sharing between the Denisovan and the Aboriginal Australian genome, compared to other Eurasians and African populations; however, it has been observed that Papuans, the population of Papua New Guinea, have more allele sharing than Aboriginal Australians.

Sahul is the name given to the single Pleistocene-era continent which connected Australia with New Guinea and Tasmania. At the time, the sea level was as much as 150 meters (490 feet) lower than it is today; rising sea levels created the separate landmasses we recognize. When Sahul was a single continent, many of the islands of Indonesia were joined to the South East Asian mainland in another Pleistocene era continent called "Sunda".

It is important to remember that what we have today is an unusual configuration. Since the beginning of the Pleistocene, Sahul was almost always a single continent, except during those short periods between glacial expansions when the sea level rises to isolate these components into north and south Sahul. The north Sahul consists of the island of New Guinea; the southern part is Australia including Tasmania.