World News – USA – Neanderthals did not use their thumbs like us, new research suggests

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

Researchers have found important physical differences in the thumbs of Neanderthals and modern humans (Homo sapiens), suggesting that the two species used their hands in different ways. Findings described in scientific reports may suggest behavioral differences between the two species, although this could be difficult to prove.

Technically, Neanderthals were humans, but they exhibited some key features that, if there today, would make them stand out in a crowd. Neanderthals were slightly shorter and thicker than people of the early modern period and had a wide nose with large nostrils. They also had weak shins and prominent forehead ridges. Their hands were bigger than ours, too, and new research shows that Neanderthal hands didn’t work the same as ours either.

« If you shook hands with a Neanderthal man, you would notice this difference, » Ameline Bardo, a postdoctoral fellow at the University of Kent’s School of Anthropology and Conservation, explained in an email. “There would be confusion about where to place the thumb, and a thumb fight would win in terms of speed and movement. ”

More practically, Neanderthals’ thumbs were better suited for pushing handles – like we hold a hammer when we bring it down. In particular, we use these power grips, as they are also called, to hold tools or other objects between our fingers and the palm of the hand while the thumb is used to direct the force. Neanderthals didn’t have hammers with handles, but these power grips were likely useful when sticking stone tools or grasping stones to use as hammers.

At the same time, this may mean that precision grips, where objects are held between the fingertip and thumb, may be more of a challenge for Neanderthals. Challenging, but not impossible. As contradicting research from 2018 shows, Neanderthals used precision grips when working manually. However, the new study suggests that precise grasping was not very comfortable for Neanderthals and that they may be more inclined to grasp force. Unfortunately, we cannot go back in time and see it for ourselves, so this is likely to remain a healthy debate among archaeologists and anthropologists for the foreseeable future.

That is, and as Bardo explained in her email, their “hand anatomy and archaeological records make it clear that Neanderthals were very intelligent, sophisticated tool users, using many of the same tools that modern day humans used. ”

Previous research in this area has shown how the shapes of the Neanderthal thumbbones differ from those of modern humans. However, these bones were examined in isolation. Bardo and her colleagues wanted to find out how Neanderthal hand bones actually moved through time and space by mapping in 3D the joints between the bones that are responsible for thumb movements.

Specifically, the researchers examined the trapeziometacarpal complex. They took a closer look at the trapezoid (the wrist bone at the base of the thumb) and the proximal end of the metacarpal bone (the first bone in the thumb that connects at the wrist). . They analyzed how changes in the shape or position of one bone affected the shape or position of another bone.

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

As the new paper shows, the joint at the base of the Neanderthal thumb is flatter than ours and has a smaller contact area. This « is better suited for an elongated thumb positioned next to the side of the hand, » Bardo said, resulting in grips that were beneficial for the use of some tools such as spears and scrapers – tools for hunting. One disadvantage of Neanderthal anatomy is that it limited powerful precision grips, such as using a small flake to cut meat, she explained.

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

This variation between the two species is “likely the result of genetic and / or developmental differences, but it can also partly reflect different functional requirements resulting from the use of different toolkits,” explained Bardo. Indeed, the variation we have seen in modern humans and Neanderthals may reflect different habitual activities with their hands between individuals within each species. ”

Again, we cannot know for sure, and this new paper is likely to restart a debate on the matter.

What we can say, however, is that Neanderthals were successful over a long period of time, around 400 years ago. 000 years ago and about 45. 000 years ago (and for reasons we still don’t really understand). . Neanderthals were also smart, as they created their own jewelry, made cave paintings, adorned themselves with feathers, and used the lissoir – a special bone – to work through tough animal skins.

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

Neanderthals, Human

World News – USA – Neanderthals did not use their thumbs like us, new research suggests

Ref: https://gizmodo.com

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