Humans can be found pretty much everywhere on the planet, but this wasn’t always the case. After Homo sapiens first emerged in Africa about 300,000 years ago, it was the beginning of a long journey as our species spread to distant corners of the world.
Previously, evidence largely supported that the early voyage from Africa to Southeast Asia and eventually Australia was by the seaside: Our ancestors stuck to coastal and island locations, moving through today’s Sumatra, Philippines, and Borneo. But new findings show that island-hopping may have been just one method of travel for the humans who became Australia’s First People. A paper published June 13 in Nature Communications outlines how modern humans passed by a cave in Northern Laos on their way through Asia, around 40,000 years earlier than anthropologists had thought.
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The findings from the Tam Pà Ling cave demonstrate two crucial discoveries—that modern humans moved through Arabia and Asia much earlier than previously known, and that these humans weren’t afraid to travel through woods and forests to get there.
“Tam Pà Ling plays a key role in the story of modern human migration through Asia but its significance and value is only just being recognised,” Fabrice Demeter, a University of Copenhagen palaeoanthropologist and one of the paper’s lead authors, said in a news release.
The story begins back in 2009 with the discovery of a skull and mandible in the cave located 186 miles from the shore. But, Laotion law doesn’t permit direct dating of fossils found at its World Heritage sites, which includes Tam Pà Ling. At the time, using a form of luminescence dating on nearby sediments, scientists placed the fossils at a minimum age of 46,000 years, which is in line with prior research investigating when humans showed up in the region.
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But, in the following years, more fossils have been found—including pieces of human skeletons beneath around 15 feet of sediment. To figure out the age of these skeletal remains, the researchers used uranium-series dating on a stalactite tip buried in sentiment, as well as uranium-series and electron-spin-resonance on two pairs of animal teeth found about 6 feet deeper. This chronology reveals a human presence in the region for at least 56,000 years, according to the new research: A fragment of human bone buried below around 23 feet of sediment suggests humans arrived between 68,000 and 86,000 years ago.
Strangely enough, this cave is not too far from Laos’ Cobra Cave, where an ancient Denisovan tooth discovery placed the mysterious human cousin in the region as far as 164,000 years ago. There may be more buried secrets of early humans waiting to be uncovered, as author and Macquarie University geochronologist Kira Westaway said in a statement: “We have much to learn from the caves and forests of Southeast Asia.”