Right-hand dominance may have been around longer than thought

Courtesy illustration

New research shows “righties” might have been more common than “lefties” since pre-Neanderthal times.

The research serves as the first potential evidence of right-hand dominance in pre-Neanderthal humans. And a University of Kansas professor emeritus was the lead author of the study.

The researchers studied scratches on teeth from a 1.8 million-year-old jaw from Tanzania. The jaw belonged to a species called Homo habilis, which is one of the least similar to modern humans in the genus Homo. The ridges on the Homo habilis teeth show right-handed eating habits.

The study was published in the Journal of Human Evolution.

“We think that tells us something further about lateralization of the brain,” David Frayer, professor emeritus of anthropology, said in a news release.

The release said multiple lines of research support the idea that brain recognition, the use of tools and the idea of a dominant hand occurred early in the history of humans.

But Frayer’s research was the first to look at the directionality of ridges on teeth for the earliest specimens.

It’s estimated that 90 percent of people are right-handed today. For apes, hand dominance is split about half and half.

“We think we have the evidence for brain lateralization, handedness and possibly language, so maybe it all fits together in one picture,” Frayer said in the release.

Gabriella Dunn: 316-268-6400, @gabriella_dunn