Neanderthal Science: Skull Trauma Study Explains Their Violent Lives

Bones can tell you a lot about the life and death of the person they once belonged to, even if that person was one of our ancient relatives. Each scar and scrape serves as a clue to how an individual lived or warred; how they journeyed and how they formed families. Historically, scientists have pointed to the bones of Neanderthals as evidence that they lived uniquely brutal lives. However, a study released Wednesday in Nature upturns that theory with demonstrable evidence that Neanderthals weren’t especially violent — they just lived in especially violent times.

Previous claims that Neanderthals were a hominin species with notably stressful and dangerous lives stemmed from studies that compared their remains to the remains of more recently alive Homo sapiens. But now, German scientists from the University of Tübingen take a different approach: In the new paper, they compare the frequency of Neanderthal traumatic injuries to the frequency of injuries attained by Upper Palaeolithic anatomically modern humans. This latter group shared similar environments with the Neanderthals and lived a similar hunter-gatherer lifestyle — making them a more suitable comparison group.

In the end, the researchers determined from the 80,000- to 20,000-year-old specimens that Neanderthals and Upper Paleolithic Homo sapiens exhibited similar overall incidences of cranial trauma. In an accompanying commentary published in Nature, paleoanthropologist Marta Mirazón, Ph.D., who was not a part of this study, writes that this finding implies that “Neanderthal trauma does not require its own special explanation, and that risk and danger were as much as part of the life of Neanderthals as they were of our own evolutionary past.”

More simply, it was just an extremely dangerous time to be alive. Patricia Kramer, Ph.D., a University of Washington anthropology professor who studies Neanderthal anatomy, told Inverse via email that while she’s not surprised that Neanderthals have similar injury patterns to modern humans of their time, knowing that as a fact adds to our overall understanding of our close relatives.

“The subsistence and mobility patterns of people living tens of thousands of years ago are different from today, so the comparison of Neanderthal behavior to ‘us’ has always been a problem,” Kramer, who was not a part of the new study, explains. “I think that as our understanding of the past matures, we realize that the distinctions we make among groups of humans are, in fact, less important and ‘real’ than we think that they are.”

In this study — which Kramer describes as a “rigorous statistical comparison” — the team assessed published descriptions of Neanderthal and modern human fossil skulls found in Eurasia. They analyzed data for 114 Neanderthal skulls and 90 Homo sapiens skulls and pinpointed nine Neanderthal specimens and 12 ancient human specimens with head injuries. For each specimen, the scientists recorded the individual’s taxon, their trauma, their sex, their age when they died, and where they were found.

Statistical models that incorporated all of this data revealed that skull injuries affected an average of 4 to 33 percent of Neanderthals and 2 to 34 percent of ancient humans — evidence that the related groups were similarly likely to experience head injuries, whether at the hands of a foe, predator, or accident.

Some differences did pop up, though: There was a significantly higher prevalence of trauma in males compared to females across both groups, and the more complete skeletal fragments showed more signs of injury. The scientists also noticed that young Neanderthals (those 30 or younger) were overrepresented in the trauma group and were more likely to die while still young. This wasn’t true for the Upper Palaeolithic humans, causing the researchers to hypothesize that young humans either were injured less or had better survival rates:

Possible explanations for these patterns include cultural or individual differences in injury proneness and healing, and different long-term consequences of healed trauma, resulting from (for example) difference in injury severity or differential treatment of the injured — which did not, however, affect the overall prevalence of trauma.

This research, as Mirazón writes, doesn’t invalidate previous estimates of Neanderthal injuries — it simply, and importantly, points out that Neanderthals were not unique in their trauma. The era itself was merciless, and all humans were left to deal with life’s oppositions.