Prehistoric fingerprint found in Spain offers clue to Neanderthal capacity for making art, study finds

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Researchers in central Spain say they may have uncovered one of the most ancient symbolic objects bearing a human fingerprint on record in Europe, dating back tens of thousands of years. Unlocking the secret identity of exactly who made the mark involved enlisting the help of forensic experts working in crime scene investigations.

The pebble marked with the print, found in the San Lázaro rock shelter in Segovia, hints at the possible capacity of Neanderthals to create symbolic art, according to a new study. The discovery adds to a growing body of evidence, including cave markings and paintings unearthed in recent years, building the case that our prehistoric relatives who went extinct about 40,000 years ago were more like modern humans than some might think.

The team of Spanish researchers spotted the oblong rock below 5 feet (1.5 meters) of sediment during an excavation in July 2022 and reported their findings in a paper published May 24 in the journal Archaeological and Anthropological Sciences. San Lázaro is a site believed to have been occupied by Neanderthals, according to the study.

“When we saw (the pebble) the first time … we were looking at the stone, all the team and students, and we were like ‘Uh, it looks like a face,’” said study coauthor María de Andrés Herrero, a professor of prehistory at the Compultense University of Madrid. This kind of finding in a Neanderthal context was unexpected, she added.

Herrero said she and her team carbon-dated the fingerprint, and they are certain it dates back about 43,000 years. The rock had been found near a riverbed and deliberately brought to the rock shelter, the researchers believe. Unlike other artifacts found in the shelter, this pebble was unique: It appeared to have no functional use and had a peculiar red dot that intrigued the researchers.

“We felt that the red dot had something, I don’t know what … and the only way we could know there was a fingerprint was to contact the main specialist in Spain (for) finding fingerprints,” Herrero said. “That’s why we contacted the police.”

Unraveling a Neanderthal mystery

With the help of experts working in crime scene investigations with Madrid’s forensic police corps Madrid, the researchers were able to confirm that a fingerprint existed within the dot.

But the police were initially skeptical about the find. “They are used to identifying fingerprints that are very recent, from 2 days, 1 week, 1 month. But 43,000 years ago — it was very weird and very difficult for them,” Herrero said.

Using forensic techniques and multispectral analysis (an advanced method of capturing images), the investigative experts and the study team were able to discern a fingerprint within the red dot. “We couldn’t believe it really,” Herrero said. The forensic investigator created a special camera to capture the evidence, and it was the first time such techniques were used to identify a Neanderthal fingerprint, according to Herrero.

The imaging technology section of the forensic team then analyzed the marking to confirm it was compatible with a human fingerprint — and to make sure it didn’t belong to any of the researchers. The police unit was able to verify that it likely belonged to an adult male Neanderthal.

“The verification of the fingerprint by forensic experts shows beyond doubt that this derived from direct contact with a human fingerprint,” said Paul Pettitt, a professor of paleolithic archaeology at Durham University in the United Kingdom.

The artifact could be the oldest complete hominin fingerprint ever found, according to Herrero. Another, possibly older print was found in Königsaue, Germany, back in 1963 — but that one is a partial fingerprint.

The San Lázaro fingerprint could also be the oldest associated with a pigment, according to the study. The researchers were able to confirm that ocher, a clay pigment, was applied to the tip of the finger that made its mark on the quartz-rich granite pebble.

Statistical modeling used by the researchers showed that the mark on the pebble was “not random” and rather, intentionally placed, Herrero said.

Pettitt said he was unsurprised by the findings.

“It represents yet another example of the emerging data that are revealing Neanderthal visual culture,” he explained. “This is an admirably clear and unequivocal example of the Neanderthal use of red pigment, one of a growing database that reveals that Neanderthals were routinely using pigments to leave marks of their bodies (hands, fingertips) on cave walls and portable objects.”

One theory is that the hollows on the rock resemble parts of a face: eyes, mouth and chin. The placement of the red dot, the researchers hypothesized, could be the place of a nose. If that is the case, the pebble marking would constitute a visual sign with a symbolic purpose.

“A meaning or message exists, however simple the object and action may appear, “the study authors wrote. They added there is reason to suspect that the pebble was intended to be a representation of a face.

The study, which called the characteristics of the pebble “exceptional,” suggests it might be a visual symbol that could be considered a piece of “portable art in some contexts.”

Neanderthals vs. modern humans

If that’s the case, scientists’ understanding of what Neanderthals were capable of could continue to shift. “The fact that the pebble was selected because of its appearance and then marked with ocher shows that there was a human mind capable of symbolizing, imagining, idealizing and projecting his or her thoughts on an object,” the study authors wrote.

Though there is no way of knowing for certain, Herrero thinks it’s a demonstration of how our understanding of the “thin line” separating Neanderthals from modern humans is getting thinner. “They were able to recognize faces in objects, as you and me are able to recognize a lion in the clouds,” she said.

Pettitt offered a similar outlook, saying the findings fit with “emerging evidence that the Neanderthal imagination was experimenting with the human form and with recognition and extension of that form within and onto objects in their natural world.”

Herrero said the research team is now planning to search for more “invisible artifacts” to help interpret the past. The forensic police will play a role in finding information not visible to the naked eye.

“We have to collaborate and integrate forensic technologies in archaeology, and maybe archaeology in forensic technologies,” she explained, saying the collaboration is “opening a new window to check our past.”

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