Modern humans may have first migrated to mainland Southeast Asia between 86,000 and 68,000 years ago. These are the dates suggested by the discovery of new fossil remains found in the Tam Pà Ling cave, in northern Laos.
These discoveries represent the first known evidence for the presence of Homo sapiens in mainland Southeast Asia. At the same time, they allow us to improve our understanding of the timing and route of dispersal of modern humans into East Asia and eventually Australia.
Previous genomic data suggests that multiple dispersals of Homo sapiens from Africa to Australasia occurred, but fossil evidence from Southeast Asia is limited.
New fossils found in the Tam Pà Ling cave prove "without a doubt" that modern humans spread from Africa through Arabia and into Asia much earlier than previously thought, according to a team of researchers.
The study published in Nature Communications indicates that the evidence found in Tam Pà Ling indicates that modern humans passed through it between 86,000 and 68,000 years ago on their way through Asia to become the first people of Australia.
This delays the arrival in mainland Southeast Asia by about 40,000 years, although genetically speaking, these early migrations did not contribute significantly to our current populations.
That temporal arc was provided by radiometric dating of a tibia and a skull fragment found in the cave. The latter, according to the authors, was "much more graceful or delicate than expected", thus resembling the morphology of more recent Homo sapiens from Asia.
The authors suggest that this may indicate that the individual was descended from a population that dispersed in the region, rather than from local populations that exhibit more robust traits.
The chronology and shape of these fossils could support genomic evidence for unsuccessful early dispersal into Australasia.
In addition, the findings confirm that human dispersals throughout this period were complex and add to our understanding of hominin diversity in northern Laos.
This evidence also proves that our ancestors not only followed the coasts, but were able to move through forested areas and very probably along inland river systems as well.
Tam Pà Ling plays "a key role in the migration story of modern humans through Asia, but its importance and value have only just been recognized," said Demeter of the University of Copenhagen, one of the paper's lead authors. .
This study provides enough dating evidence to say for sure when Homo sapiens first arrived in the area, how long they were there, and what route they may have taken, said Kira Westaway, also a signatory to the paper, from Macquarie University in Australia. .
Tam Pà Ling cave is very close to the recently discovered Cobra cave, frequented by Denisovans some 70,000 years earlier.
Despite the lack of evidence for an early arrival in mainland Southeast Asia, this area could be a dispersal route previously used by our ancestors, long before Homo sapiens, the researchers said.
