DNA from a lock of hair has helped scientists prove that about 70,000 years ago, indigenous Aboriginal Australians were the first to separate from other modern humans.
The finding challenges current theories of a single phase of dispersal from Africa.
An international team of researchers published their findings in the journal Science.
Their report argues that while Aboriginal populations were moving across Asia and into Australia, the remaining humans stayed around North Africa and the Middle East until 24,000 years ago.
It was only then did they start to move and colonise Europe and Asia. By then, the indigenous Aborigines had been established in Australia for 25,000 years.
Co-author Dr Joe Dortch, an archaeologist at the University of Western Australia, says the work is significant because it shows the timeline for people in Australia is more than 50,000 years.
"So far there are no [archaeological] sites that are over 50,000
years old so it puts a time limit on that and focuses our future
efforts," he says.
Dortch believes the finding will foster a sense of pride in modern Australian Aborigines.
"It shows Aboriginal Australians have the longest branch of history in one particular place of anyone in the world.
"No one else in the world can say 'I am descended from people who have been here 75,000 years'."
The research also highlights the exciting future possibilities of comparing the genomes of multiple individuals to track migration of small indigenous groups.
Dr Francois Balloux, of Imperial College London described how a "population expanded along the coastline because of the rich resources available there. They could walk almost the entire way because the sea level was much lower". Just one small sea crossing would be required to reach Australia.
Any potential archaeological remains of this journey, which lasted 25,000 years, would be lost to the deep sea under rising sea levels.