Pieces of human skull found in the "Cave of the Monkeys" are being reported as the earliest skeletal evidence of ancient migration to Asia, according to archeologists.  

There has been prior archaeological evidence that suggested modern humans once migrated out of Africa into Southeast Asia, but with the lack of fossils to support this theory, it has always been up for debate, until now.

The fossils supporting the migration to Southeast Asia were unearthed in 2009 in Laos in the limestone cave at the top of the Pa Hang Mountain.

According to Dr. Laura Shackelford, anthropologist at the University of Illinois, the remains are particularly old for a modern human fossil and exceptionally old for human remains found in that region.

The skeletal fragments were uncovered under layers of sediments that had washed into the cave over the years. Archeologists believe since there is no evidence of ceremonial burial, the remains may have been washed into the cave from outside as well.

Through uranium/thorium dating, a radiometric dating technique used to determine the age of calcium carbonate materials, it was determined that the remains are about 63,000 years old. Additionally, based on the layer of the soil the fossils were found in, scientists believe the remains may have washed into the cave between 46,000 and 51,000 years ago.

Shackelford believes this new discovery supports the "Out-of-Africa" theory, which states every living human once descended from a small group in Africa, rather than the multi-regionalism, which stated modern humans evolved in all regions simultaneously.

Currently scientist are attempting to extract DNA from the remains to see how they may or may not relate to later humans that once lived or are presently living in the area.

Shackelford is optimistic about future findings. She is certain that with the numerous amounts of limestone caves in the particular area they can continue to look for early modern humans.

This study was published in the Proceedings of the National Academy of Sciences.