The first genome of a 100-year-old hair from an Australian aborigine establishes the arrival of migrants from Africa to Australia about 50,000 to 70,000 years ago.

The lock of hair was donated to British anthropologist Alfred Haddon in the early 20th century by an aboriginal man from Western Australia's Goldfields region. DNA sequencing of the hair showed the man was a direct descendant of African migrants.

It showed no genetic input for modern European Australians who migrated to the country much later.

University of Western Australia archeologist Dr Joe Dortch, who co-authored the study, said the finding is significant because it indicated a timeline for Australian inhabitants of at least 50,000 years.

"So far there are no (archeological) sites that are over 50,000 years old so it puts a time limit on that and focuses our future efforts.... No one else in the world can say, 'I am descended from people who have been here 75,000 years'," ABC News quoted Mr Dortch.

The findings appear to provide an answer to the question if there was a single wave of migration out of Africa into Europe, Asia and Australia. One theory is that the first migrants to Australia were branched off from the Asian population who were differentiated from European ancestors.

Mr Dortch said the study indicated that when the first migrants in Australia arrived, the Asian and European ancestors have not differentiated and were probably still in Africa or the Middle East.

David Lambert, the co-author and professor of evolutionary biology at Griffith University, pointed to the natives in Papua New Guinea and Aetas of the Philippines as the ones closest to the population of Australian aborigines.

Hair analysis expert Silvana Tridico, who contributed to the study published Friday in the Science journal, said that he was able to see features on the hair shafts such as ochre and weather conditions in the harsh outback. He said the research showed that hair preserved not under frozen condition could still be used for genome sequencing minus the risk of modern human contamination typical in ancient bones and teeth.

Stanford University paleoanthropolist Richard Klein added that most of the early migrations to Australia, whether by people or animals, were not successful because of the continent's desert land. However, the aboriginal Australians found they way to the country's south which has vegetation and helped the migrants survive to this day.