Researchers have discovered an ancient skull believed to be the oldest modern human fossil found in Southeast Asia.

A team of researchers recovered the skull from the Annamite Mountains in northern Laos, and using techniques such as uranium/thorium dating they determined the skull's age to be around 63,000-years-old.

Although fossil remains of ancient modern humans have been found earlier in China or in Island Southeast Asia that is around the same age as the newly found skull, they neither have definitive human features nor have been well dated. The skull found in Laos is the first fossil evidence that supports the DNA data which clearly sheds light on the earliest migration of humans to Southeast Asia 60,000 years ago.

"It's a particularly old modern human fossil and it's also a particularly old modern human for that region," University of Illinois anthropologist Laura Shackelford, who led the study, said in a statement from the university.

"There are other modern human fossils in China or in Island Southeast Asia that may be around the same age but they either are not well dated or they do not show definitively modern human features. This skull is very well dated and shows very conclusive modern human features," she said.

While the researchers found the skull below the surface of the cave, they pointed out that the cave wasn't a burial site. They noted that the person would have died outside the cave and the body would have washed into the cave later.

The discovery has showed evidence that the ancient modern humans from Africa migrated to Southeast Asia much earlier than previously thought at a relatively rapid rate.

Shackelford said that the fossil recovery also revealed that the ancient humans not only migrated south to the islands of Southeast Asia and Australia, but they also wandered in the northern regions in very different terrains. "This find supports an 'Out-of-Africa' theory of modern human origins rather than a multi-regionalism model," she said.

"Given its age, fossils in this vicinity could be direct ancestors of the first migrants to Australia. But it is also likely that mainland Southeast Asia was a crossroads leading to multiple migratory paths," she added.

The findings of the study are published in the journal Proceedings of the National Academy of Sciences.