In the study published this week in human origins paper Nature, scientists were able to trace the journey made by intrepid ancient humans by sifting through clues left in the DNA of modern populations in Australia and Papua New Guinea, the Guardian reported on Wednesday.
The study showed that they were probably the first humans to cross an ocean.
Professor Eske Willerslev, an evolutionary geneticist who led the work at the University of Copenhagen, said: "This story has been missing for a long time in science. Now we know their relatives are the guys who were the first real human explorers. Our ancestors were sitting being kind of scared of the world while they set out on this exceptional journey across Asia and across the sea."
The study revealed that early humans would have encountered other roving hominin species, including an unknown human relative who has now been shown to have contributed around 4 per cent to the Indigenous Australian genome.
Willerslev's study also resolves around the apparent discrepancy between genetic findings implying that indigenous populations have been in Australia for tens of thousands of years and the fact that the languages spoken by these populations are only around 4,000 years old.
"You see a movement of people spreading across the continent and leaving signatures across the continent," said Willerslev. "That is the time that this new language has spread. It's a tiny genetic signature."
Aubrey Lynch, an Indigenous elder from Australia's Goldfields region, said: "This study confirms our beliefs that we have ancient connections to our lands and have been here far longer than anyone else."
