A new analysis of Australia's oldest human remains suggests humans arrived on the continent about 50,000 years ago.
The Mungo burials have cast doubt on 'Out of Africa'
The evidence is based on a re-examination of the so-called Mungo Man skeleton, unearthed in New South Wales (NSW) in 1974.
Scientists say the individual was probably buried about 40,000 years ago, when humans had been living in the area for some 10,000 years.
The data will come as a relief to palaeontologists who support the "Out of Africa" theory.
We find no evidence to support claims for human occupation or burials near 60 kyr ago
Some had suggested the skeleton was 60,000 years old, challenging the popular idea that all people alive today are descended from a group that arose in Africa some 100,000 years ago.
Under the "Out of Africa" hypothesis, ancient people could not have arrived in Australia before about 50,000 years ago [kyr ago] because their spread across the world from Africa was very slow.
Mungo Man's discoverer, James Bowler of the University of Melbourne, says the new data corrects previous estimates for the date of human burials at the site.
Discovered at Lake Mungo in far west NSW in 1974
Had been covered in red ochre during a burial ritual
Hands were interlocked and positioned over the penis
Found in same area as cremated remains of female skeleton known by local Aborigines as Mungo Lady
"Our study shows that humans were present at Lake Mungo as early as 50-46 kyr ago," he said.
"We find no evidence to support claims for human occupation or burials near 60 kyr ago."
Lake Mungo is one of the most important archaeological sites in the world.
Two skeletons have been found in the area: "Mungo I'" the first recorded cremation, dated at about 26,000 years ago and "Mungo III", the world's oldest ritual ochre burial, and source of the world's oldest mitochondrial DNA.
The new analysis is based on the dating of sand taken from the burial site.
An earlier team, led by Alan Thorne, put the date at 60,000 years ago based on samples taken further away.
The latest research is published in the journal Nature.