Neanderthal used precision grips

The outdated stereotype of the heavy-browed oafish Neanderthal has been dealt another blow. A study of Neanderthal hands reveals that our Palaeolithic cousins used precision hand movements in their daily activities, rather than brute force.

The study, published in the journal Science Advances, finally brings fossil bone evidence into alignment with archaeological finds that increasingly paint a picture of a rich and sophisticated Neanderthal culture.

Neanderthals were traipsing around western Eurasia between 400,000 and 40,000 years ago. The reason for their demise is unclear, but evidence for an overlap of several millennia with anatomically modern humans has led many to believe they were outwitted by our ancient forebears.

Their thickset stature and sturdy hand bones further cemented the impression that Neanderthals were simple brutes, more adept at using force rather than finesse.

In recent years, archaeological finds have challenged this view. Cave paintings, decorated shells, etched flintstones, and jewellery attributed to Neanderthals all point to a species capable of symbolic thought. Other finds, such as specialised bone tools for processing animal hides, small stone (“microlithic”) tools, and fire-aided adhesives, suggest a level of dexterity seemingly at odds with their big-boned, muscular hands.

Now, a fresh analysis of Neanderthal hands by scientist at the Senckenberg Centre for Human Evolution and Palaeoenvironment at the University of Tübingen in Germany and colleagues at Switzerland’ University of Basel reveals that, contrary to popular belief and previous fossil analyses, Neanderthals frequently used precision grips, such as pinching between thumb and index finger.

“Like modern humans, Neanderthals were competent tool makers and tool users, who were using delicate and precise hand and finger movements in their daily activities,” says Katarina Harvati, who led the study.

The team focused its attention on muscle attachment scars, called entheses. These markings provide the only window into what a person’s hand musculature looked like, and what movements they regularly performed over their lifetime.

Previous studies of muscle attachment scars have been marred by doubts about the technique’s veracity. One person’s measurements and conclusions might not align with another’s, and a clear line between repeated movements and scar shape and size can’t always be drawn.

To eliminate these problems, Harvati’s team used 3D scans to accurately measure scar size, and then, instead of looking at individual scars, used a statistical method to pull out groups of muscles that act in concert. Precision grips, which use the thumb and fingertips, become distinct from power grips – such as that used to hold a hammer – that involve the entire hand.

The team analysed Neanderthal and Paleolithic human hands, and compared these with a collection of skeletal remains held at the Natural History Museum in Basel.

“This unique collection from the nineteenth century comprises fully documented skeletons, including information about the circumstances of their life and their profession,” says the museum’s Gerhard Hotz.

“If, for example, we examine a blacksmith’s hand, we can show by means of the muscle attachment points that he regularly used ‘power grips’ during his day-to-day activities.”

All of the four Neanderthal hands showed signs of habitual use of precision rather than power grips. Early humans, in contrast, were divided into power grip users and precision grip users, suggesting an early division of labour in Paleolithic humans. Whether that division occurred along gender lines remains a question that will require additional hand fossils to be unearthed.

Others aren’t surprised by the finding.

“When I read it, I was like, ‘yeah, well, that makes total sense’,” says archaeologist Michelle Langley, from Griffith University in Australia, who wasn’t involved in the study.

Given archaeological evidence showing a complex Neanderthal culture, she says, “you’d expect that they’d have quite good precision grasping skills.”