86,000-Year-Old Human Remains Rewrite History of Human Expansion

When The Croods hit theaters in 2013, it provided moviegoers with a comedic window into what it might have been like in the early days of human evolution. We follow a family of indeterminate “cave people” as they encounter an array of wild (and mostly imagined) animals and other environmental threats in search of a new home.

As the story progressed through a sequel and an episodic animated series (now streaming on Peacock!), they encounter not just interesting animals, but other groups of humans who are seemingly different from them. While the events of The Croods are invented and often fanciful, they might not be a wholly inaccurate view of what it might have been like for early humans to disperse across an uncharted planet. Precisely how and when that happened isn’t wholly clear, but a recent discovery from a cave in Laos is shining a new light on the story of early human migration.

Humans May Have Arrived in Asia Earlier Than Expected

Researchers have been digging at Tam Pà Ling cave in Laos, for more than a decade. The findings have been infrequent, but the most recent is a game changer. Over the last decade of excavations, scientists dug seven meters into the earth of the mountaintop cave, looking for evidence of human habitation.

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That’s particularly challenging in southeast Asia, because the climate decomposes bones more easily, leaving the human fossil record in the area painfully sparse.  In total, researchers have recovered seven bone fragments from early humans, most of which date to between 46,000 and 70,000 years ago. Those dates line up with the prevailing narrative of human expansion. It’s widely believed that humans moved out of Africa in a mass exodus stretching between 130,000 and 80,000 years ago.

Of the fragments found at Tam Pà Ling, five correspond to that narrative, but two newly discovered fragments suggest things were more complicated. A piece of skull and a splinter of shin bone recently discovered at the cave are substantially older, suggesting that humans may have spread more gradually through a number of smaller migrations.

The life of the cave dwellers. Illustration from 19th century. Photo: clu/Getty Images

Researchers used a combination of dating methods, including dating the sediments and animal teeth found alongside the bones. Those combined methods date the skull fragment to somewhere between 70,000 and 77,000 years ago. The shin bone, by contrast, is roughly 86,000 years old, significantly older than the other bones found in the cave.

The characteristics of the bone fragments at Tam Pà Ling also support a more complicated expansion process. While all seven of the bones from the cave are from Homo sapiens, researchers found that the oldest bones have features corresponding to modern humans, while the younger ones have a mixture of features from modern and archaic humans, like a more pronounced brow. It’s possible that early populations of more modern humans started to migrate earlier than other populations, but to find out for sure we’re going to need more data.

Unfortunately, there is no evidence that any of the ancient humans at Tam Pà Ling cave wore living sloths as fashion accessories.

For innovations like that, you’ll have to watch The Croods: Family Tree, streaming now on Peacock!