Handedness of Early Humans Speaks Volumes

Not many Neanderthal skeletons have been found, but one of the more complete ones, dubbed “Regourdou,” was found in France in 1957 buried near the Lascaux Cave. “This skeleton had a mandible and parts of the skeleton below the neck,” according to anthropologist David Frayer, author of a recent study of the skeleton. “Twenty-plus years ago, some people studied the skeleton and argued that it was a right-handed individual based on the muscularity of the right arm versus the left arm.” (With use, the bones of the dominant arm get a bit thicker.) But that finding remained controversial. Why? Because the implications that Neanderthals could be right- or left-handed suggests Neanderthals also had linguistic abilities. Frayer’s team now reports a strong correlation between Regourdou’s arms and teeth, a finding with broad implications for anthropological understanding of early humans.

What do teeth have to do with handedness? Examination of Regourdou’s teeth and the teeth of over two dozen other Neanderthals and Homo heidelbergensis reveals “labial scratches.” These scratches are on the “lip-side” of their front teeth. (Labial means “lip.”) Similar scratches are found on the teeth of some living hunter-gatherer people. They seem to have been produced by inadvertently striking the teeth with a cutting tool while holding an object with the teeth and one hand and sawing with the other. Because these scratches are obliquely angled, they appear different when made with the right hand or the left.

These scratches on the “lip-side” of Regourdou’s front teeth are typical of scratches made by a cutting tool wielded by a right-handed human steadying an object with his teeth. Regourdou was a Neanderthal. Scratches like these on the teeth of many Neanderthals and Homo heidelbergensis, 27 individuals altogether, suggest only 7% were lefties. Image from doi:10.1371/journal.pone.0043949.g004.

“Labial scratches” have been found on the teeth of European Neanderthal specimens, including Regourdou, and also on the Homo heidelbergensis skeletal remains from Sima de los Huesos, a cave in Spain’s Atapuerca Mountains. Because Regourdou’s mandible and arm bones are available for study, Frayer’s group was, by studying the scratches and the diameter of arm bones, able to corroborate earlier conclusions that Regourdou was right-handed. And if right-handed, then Regourdou may have had some things to say!

It turns out that 16 of the 18 European Neanderthal specimens have right-handed scratches. And all of the tooth sets from Sima cave bore the marks of right-handed owners. Overall, 93% of these early humans, based on dental evidence, were right-handed. This percentage reflects the right-handed propensity seen worldwide in humans today.

Handedness is a uniquely human characteristic, and about 90% of modern humans are right-handed.

Handedness is a uniquely human characteristic, and about 90% of modern humans are right-handed. Handedness starts in the womb, as unborn babies show a decided preference in thumb-sucking, and that preference correlates with their handedness in adolescence.1 This handedness is associated with dominance of the right- and left-brain for certain types of functions, and such “brain lateralization” is also a uniquely human trait. And language—another uniquely human ability—is primarily a function of the left side of the brain.

Evolutionary anthropologists have long resisted the idea that Neanderthals had a dominant hand because that would imply they had the capacity for language, a novel concept for beings habitually considered lower on the evolutionary scale than modern humans. Archaeology has not found any evidence of writing thus far, but the Neanderthals’ intellectual reputation has been improving in recent years as more and more discoveries suggest early humans could think abstractly. Recent findings in Spain have suggested Neanderthals did paint. (See our illustrated report at “Handprints in Northern Spain.”) Anatomy of the Neanderthal and Homo heidelbergensis hyoid bone—the little bone that supports the tongue—shows it is characteristic of humans and not apes, as we recently discussed. That finding supports a 2011 study’s conclusion that Neanderthals were probably capable of “vocalizing voluntarily, with communicative intentions and in a sophisticated way.”2

These findings do not surprise us, as God’s eyewitness account reports He created Adam and Eve the same day He created land animals. The biblical account has no room for evolution. And He created humans in His own image. Adam and Eve were able to speak from the beginning. Neither linguistic ability nor language had to evolve. Since Neanderthals and Homo heidelbergensis were simply varieties of human beings who eventually became extinct by the end of the Ice Age, we would expect them to have had quite a lot to say. After all, their relatives were among those dispersed from the Tower of Babel after confusion of their languages. The Bible’s account of history makes sense of the growing body of evidence that these early people were pretty much like people today.