For scientists, it has long remained a mystery how Australian Aborigines came to colonise the world's largest island.
But a controversial new theory from molecular anthropologist, Dr Sheila van Holst Pellekan, suggests that indigenous Australians may be the result of the meeting of ancients migrating from Indonesia and Papua New Guinea.
From abc.net.au :
Previous genetic analysis shows that modern humans took two migration routes out of Africa 100,000 to 150,000 years ago, she says.
One group went north into Europe and Northern Eurasia, the other along the coast via Saudi Arabia, India and South-East Asia.
Dr van Holst Pellekaan analysed mitochondrial DNA (mtDNA) from Aboriginal people in western New South Wales and Central Australia.
She says she found evidence of two ancient genetic groups that appear to be linked to these two migration routes.
Dr van Holst Pellekaan says some archaeologists argue there was more than one founding population of Australia, and her research is the first genetic evidence that could be used to support this.
It is possible that some Australians came in from the north via Papua New Guinea and the other took a more southerly route via Indonesia, she says.
Archaeologist Dr Colin Pardoe, who is speaking at the conference on a related topic, disagrees.
He believes the diversity of early Australians could have arisen from one group that came in from South-East Asia and then diversified as it adapted to different environments.
"The idea of two founding populations is speculative," she says. "I can't prove it either way."
Dr Van Holst Pellekaan says despite the links with the global lineages that came out of Africa, the Australian groups are quite different from those shown in samples from Papua New Guinea, the Andaman and Nicobar Islands and Malaysia.
"[People] have to have been in Australia for a very long time for that diversity to generate. We're saying at least 40,000 years," she says.
