Prehistoric cave discoveries hint at shared culture between Neanderthals and humans

This Friday, March 20, 2009 file photo shows reconstructions of a Neanderthal man, left, and woman at the Neanderthal museum in Mettmann, Germany. (AP Photo/Martin Meissner, File)

Ancient DNA revealed that our species, Homo sapiens, once interbred with Neanderthals, but what was the nature of those Stone Age encounters tens of thousands of years ago?

Discoveries unearthed in a cave in what’s now Turkiye indicate the two groups did not merely cross paths but may have shared some cultural traditions, making similar tools and collecting the same kind of shell.

“Our findings suggest that Neanderthals and Homo sapiens likely shared more than just the same landscape,” lead author İsmail Baykara said via email, discussing the new research published Monday in the journal PNAS.

“Although we cannot yet prove direct contact, the remarkable continuity in technology, hunting practices, and the transport of bead-seashells is consistent with the idea that these populations interacted and shared cultural traditions over time.”

While archeologists have known about the Üçağızlı II cave in southern Turkiye for some time, the first systematic excavation began in 2020, said Baykara, a professor in the department of archeology at Gaziantep University in Turkiye.

Fossils found in the cave — four individual teeth and a partial jawbone with two teeth still attached — showed that Neanderthals inhabited the cave between 77,000 and 59,000 years ago, with Homo sapiens later occupying the cave between 59,000 years ago and 47,000 years ago. These timeframes were determined by dating the sediment layers in which the fossils were encased.

During that time, the two species made similar flint tools in a style known as Mousterian after the rock shelter in France where the tools were first identified. The two species also hunted the same types of animals, such as wild goats, deer and boars. One of the researchers’ biggest surprises was the discovery of a particular type of shell from the mollusk Columbella rustica, too small to provide sustenance, in both the Neanderthal and Homo sapiens layers.

While some of the C. rustica shells had been perforated, suggesting they could have been ornamental, the study authors described them as “manuports,” or objects transported by a person from their places of origin. Although the mollusk shell has previously been linked exclusively with Homo sapiens, the authors said it is very likely that Neanderthals also valued this seashell.

“Neanderthals deliberately collected and transported this shell from the Mediterranean coast despite many other shell species being available, and modern humans at the site also collected Columbella rustica,” said study coauthor Naoki Morimoto, a researcher at Kyoto University in Japan.

Out of Africa

The Üçağızlı II cave is one of only a handful of known sites that date back to a pivotal but little-known period in the human story.

Around 60,000 years ago, a sweeping migration of our species out of Africa ultimately led to modern humans residing in every corner of the globe, with a few pioneering groups leaving the continent much earlier. Scholars think that during this larger migration modern humans likely encountered and interbred with Neanderthals in places such as modern-day Turkiye.

However, this hypothesis comes mainly from population patterns modelled from DNA sequences. Direct archaeological evidence from this critical period in the Levant, the region that now roughly equates to the Middle East and Turkiye, is scarce and fragmentary. It’s not clear, the new study noted, whether the Homo sapiens who sheltered in the cave were part of this major wave of migration or the descendants of the early pioneers.

Ludovic Slimak, an archeologist at the French National Centre for Scientific Research (CNRS) and the author of the “The Last Neanderthal: How Humans Die,” said the cave represented “a very important discovery,” demonstrating that modern humans did not necessarily arrive on the scene and replace Neanderthals with a new and superior culture.

“To me, the most important point is not simply that Neanderthals and modern humans used similar tools or collected similar shells,” he noted in an email.

“What is much more interesting here is that, within the chronological range of the Homo sapiens layer, modern humans appear to be involved in a deeply local, well-rooted Mousterian tradition.”

Slimak said the site provided a fascinating contrast to Grotte Mandrin, an archeological site in southern France where Neanderthals and Homo sapiens once both lived. Slimak has led excavations at that site.

There, Homo sapiens, who lived in the rock shelter at roughly the same time their counterparts occupied the cave, used very different stone tools, perhaps even bow-and-arrow technology, that were much more finely crafted than the bulkier Mousterian tools found in the Neanderthal layer at Grotte Mandrin and used by both species at Üçağızlı II.

“The two sites do not tell the same story,” Slimak said. “Together, they suggest a much more complex picture, with multiple Homo sapiens populations, multiple cultural trajectories, and probably several waves of expansion, interaction, disappearance and replacement.”

Baykara added that more archaeological evidence is needed to understand whether the Üçağızlı II cave was an outlier or not.

“This unique situation suggests that culture is shaped not only by biology but also by local traditions, allowing different species in the same region to maintain shared behaviors for thousands of years,” Baykara said.

By Katie Hunt, CNN