Jewelry

About 42,000 years ago, the Neanderthals, the stocky cousin of modern humans, fashioned tiny jewelry beads from animal teeth, shells and ivory, a new study finds.

The finding is a momentous one, as it suggests that Neanderthals could engage in symbolic expression, that is, the ability the make art, before they went extinct about 30,000 years ago, the researchers said.

"We now know that some of the last Neanderthals in Europe made artifacts that we do not see in Neanderthal material culture before that time," said study lead researcher Frido Welker, a doctoral student of human evolution at the Max Planck Institute of Anthropology in Germany. [In Photos: Neanderthal Burials Uncovered]

The discovery is based on the artifacts and bony remains found in the Grotte du Renne cave in Arcy-sur-Cure, an area located about 125 miles (200 kilometers) southeast of Paris. After the cave was discovered in 1949, its contents were dated to about 50,000 to 40,000 years ago, a period during which modern humans were sweeping across Europe and displacing the Neanderthals, the researchers said.

The entrance to the Grotte du Renne in France.

At first, anthropologists credited the beads to the Neanderthals. But the prevailing view on Neanderthals was that they didn't have the brainpower to craft such items, prompting many experts to wonder whether the excavation team had made a mistake in attributing the beads to Neanderthals when, perhaps it was modern humans who made the ornaments, according to Phys.org.

The researchers of the new study set out to answer that question once and for all.

"We wanted to know whether an archaeological culture called the Châtelperronian was made by Neanderthals or modern humans," Welker told Live Science in an email. "If they were modern humans, they would be some of the earliest modern humans on the European continent, and might have played a role in Neanderthal extinction."

Protein investigation

The ancient bone fragments in the cave did not have enough preserved DNA for a thorough analysis, so the researchers turned to another identifying factor: proteins.

They used several mass-spectrometry techniques to study the proteins preserved in about 200 ancient bone specimens from the cave, Welker said. The mass-spectrometry methods were key to the experiment, he added. That's because proteins are made out of amino acids, which are joined together on a string.

Bone awls, known as poincons, are not normally present in Neanderthal material culture, but they were found in the Châtelperronian of the Grotte du Renne.

Each amino acid has a different weight, or mass. "By using massspectrometry, we can establish the different sequences of amino acids in our sample and compare that with existing protein databases," Welker said.

They found that while the majority of the bone fragments belonged to horses or aurochs (wild cattle), some were clearly hominin, Welker said. Moreover, they identified an amino acid sequence that was unique to Neanderthals, proving that the bones did not belong to modern humans or the Denisovans, another kind of ancient human, he said. [The 10 Biggest Mysteries of the First Humans]

Results from additional testing methods, such as direct radiocarbon dating and ancient mitochondrial DNA analysis, also pointed to the bones belonging to Neanderthals, he said.

'Very young infant'

One of the proteins found in the Neanderthal bones was a type of collagen that is found only in growing bones. In addition, the specimen had a high proportion of a certain kind of nitrogen isotope (a variation of an element, but with a different number of neutrons) that is associated with breastfed infants. 

"We identified ancient proteins in these Neanderthal bone specimens that indicated they belong to a very young infant, probably around the age of 1 year old," Welker said.  

The baby likely lived about the same time as the Neanderthals crafted the 1.2-to 2.4-inch-long (3 to 6 centimeters) beads, the researchers said. However, "we don't know if they belong to a single 'necklace' or were worn in different ways, and they were found in different areas of the Grotte du Renne," Welker said.

"It is now up to the archaeologists to try and explain how this happened," Welker said. "Did they learn [bead-making] from modern humans? We know they interacted, as there is genetic interbreeding between Neanderthals in modern humans in our DNA. Or maybe they imitated? Or invented such artifacts themselves independently?"

It's also possible that the Neanderthals got the beads from modern humans, possibly as a courtship gift, according to Phys.org.

The findings were published online Friday (Sept. 16) in the journal Proceedings of the National Academy of Sciences.

Original article on Live Science.