Neanderthals didn’t use their thumbs like modern humans

Reconstructions of a Neanderthal man and woman.

Reconstructions of a Neanderthal man and woman.
Photo: Martin meissner (AP)

An analysis of Neanderthal hand bones suggests that these extinct humans possessed thumbs better suited to power grips, as opposed to precision grips, which could mean they used their hands differently than we do.

Researchers have found key physical differences in the thumbs of Neanderthals and modern humans (homo sapiens), which suggests that the two species used their hands in different ways. The conclusion, as described in scientific reports, potentially speaks of differences in behavior between the two species, although this may be difficult to prove.

Technically speaking, Neanderthals were humans, but they exhibited some key characteristics that, if present today, would make them stand out in the crowd. Neanderthals were a bit shorter and thicker than early modern humans, and they had wide noses with large nostrils. They also had weak chins and prominent brow ridges. Their hands were also larger than ours, and as the new research points out, Neanderthals didn’t function exactly the same as ours.

“If you squeezed a Neanderthal hand, you would notice this difference,” Ameline Bardo, postdoctoral researcher at the School of Anthropology and Conservation at the University of Kent, explains in an email. “There would be confusion over where to place the thumb, and for a thumb fight I think you would win in terms of speed and movement.”

Good to know.

More concretely, Neanderthals’ thumbs were better suited for squeezing handles – like the way we hold a hammer when we lower it. Specifically, we use these electric handles, as they are also called, to hold tools or other objects between our fingers and the palm, while the thumb is used to direct force. Neanderthals did not have hammers with handles, but these electric handles were probably useful when hafting stone tools, or when grabbing stones to use as hammers.

At the same time, perhaps it means that precision grips – in which objects are held between fingertips and thumbs – may have been more difficult for Neanderthals. Difficult, but not impossible. As contradictory research Starting from the 2018 shows, Neanderthals applied precision grips during manual labor. What the new research suggests, however, is that precision grip was not very comfortable for Neanderthals, and that they were perhaps more prone to PTO. Unfortunately, we cannot go back in time and see for ourselves, so this will likely remain a healthy debate among archaeologists and anthropologists for the foreseeable future.

That said, and as Bardo explained in his email, “Their hand anatomy and archaeological records clearly show that Neanderthals were very smart and sophisticated tool users and used many of the same tools as contemporary modern humans.

Previous research in this area has shown how the shapes of the Neanderthal thumb bones vary from those of modern humans, but these bones have been studied in isolation. Bardo and his colleagues sought to learn how Neanderthal hand bones moved in time and space, which they did by 3D mapping the joints between the bones responsible for thumb movements.

Specifically, the researchers studied the trapezo-metacarpal complex. More specifically, they examined the trapezius (the wrist bone at the base of the thumb) and the proximal end of the metacarpal (the first bone of the thumb that joins the wrist). They analyzed how changes in the shape or position of one bone influenced the shape or position of another.

For analysis, the scientists studied the fossilized remains of five Neanderthals (admittedly a small sample), which were compared to bones of five early modern humans and 50 recent modern individuals. The results indicated a “privileged thumb position” in Neanderthals that was typically different from ours.

As the new document points out, the knuckle at the base of the Neanderthal thumb is flatter than ours and with a smaller contact area. This “fits better with an extended thumb placed along the side of the hand,” according to Bardo, leading to grips that were advantageous for using certain tools, such as spears and scrapers – tools used for hunting. A downside of Neanderthal anatomy is that it limits strong precision holds, like using a small flake to cut meat, she explained.

In modern humans, these joint surfaces tend to be more curved, which is better for gripping objects between the pads of the finger and thumb, i.e. precision grip.

This variation between the two species is “likely the result of genetic and / or developmental differences, but may also reflect, in part, different functional requirements imposed by the use of various toolkits,” Bardo explained. “Indeed, the variation that we found among modern humans and Neanderthals may reflect different usual activities with their hands between individuals within each species.”

Again, we cannot know for sure, and this new document will likely reignite debate on the matter.

What we can say, however, is that the Neanderthals were successful for a long time, appearing around 400,000 years ago, and having disappeared around 45,000 years ago (and for reasons we still don’t understand. not really). Neanderthals were also cunning, as they created their own jewelry, made cave paintings, decorated with feathers, and used the smoother—A specialized bone – for working on tough animal hides.

If precision grips were difficult for Neanderthals, we certainly wouldn’t know from the cultural archaeological records they left behind.

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