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Neanderthals could grab a hammer but would have struggled to pick up a coin because the joints in their thumbs made precision grips more challenging than “ strings of force ”
- The researchers compared the thumb bones of Neanderthals and modern humans
- The joints between the former were flatter and had a smaller contact surface
- This would have more suitable grips where the thumb is held extended
- Neanderthals would have been capable of precision grappling, but not that easily
Neanderthal thumbs would have meant they could easily grasp a tool like a hammer, but they would have struggled to pick up a coin, according to a study.
UK-led experts compared thumb bones in Neanderthals and modern humans, and found that the former were more suited to power squeeze grips.
Neanderthals had a flatter and smaller contact surface between their first metacarpal and trapezoidal bones, so such grips with an extended thumb are easier.
On the contrary, our hands are better evolved for so-called precision grips, in which objects are held between the tip of the thumb and the finger.
Power squeeze grips on the other hand see objects held between the fingers and palm – with the thumb extended straight and used to direct force.
Neanderthal thumbs would have meant they could easily grab a tool like a hammer, but they would have struggled to pick up a coin. In the photo, the thumb bones of a modern human (left) and five Neanderthals (right). The yellow highlight represents the contact surface
In their study, anthropologist Ameline Bardo of the University of Kent and colleagues mapped the so-called trapeziometacarpal complex – the joints between the bones involved in thumb movement – of five Neanderthals in three dimensions.
They compared these reconstructions with similar ones taken from the remains of five early modern humans and 50 modern-day adult humans.
The team found that the relative shape and orientation of these joints relative to Neanderthals and modern humans were indicative of different styles of repetitive thumb movements.
The joint at the base of the Neanderthal thumb was flatter, with a smaller contact surface – and there it was more suited to an extended thumb, positioned along the side of the hand, the researchers concluded.
This thumb posture, they added, suggests the regular use of compression grips, such as those humans now use to hold tools with handles.
In modern humans, the joint surfaces themselves are typically larger and more curved, an advantageous configuration when grasping objects between the finger and thumb pads, in what is known as precision grasping.
The researchers said that although the Neanderthals’ thumb morphology appears more suitable for PTOs, they would still be capable of precision hand postures.
However, they would find it more challenging than modern humans.
UK-led experts compared thumb bones in Neanderthals and modern humans, finding that the former were more suited to ‘power squeeze’ grips (as pictured) where objects are held between the fingers. and the palm, while the thumb is extended and used to direct the force. Previously, the blue bone is the first metacarpal and the purple one is the trapezius
The team said comparing the shapes of Neanderthal hand bones from fossil remains to those of modern humans can provide additional insight into the behaviors of our ancient relatives and early use of the tools.
“The results show a distinct pattern of shape covariation in Neanderthals, consistent with more extended and adducted thumb postures that may reflect the habitual use of commonly used grips for handled instruments,” the researchers wrote in their paper.
The results, they added, “underscore the importance of holistic joint shape analysis for understanding the functional capabilities and evolution of the modern human thumb.”
Full study results were published in Scientific Reports.
Neanderthals had a flatter and smaller contact surface between their first metacarpal and trapezoidal bones, so such grips with an extended thumb are easier. On the contrary, our hands are better evolved for the so-called precision grips, in which objects are held between the tip of the thumb and the finger, as in the photo
Close relatives of modern humans, Neanderthals went extinct 40,000 years ago
Neanderthals were a close human ancestor who mysteriously went extinct some 40,000 years ago.
The species lived in Africa with early humans for millennia before moving to Europe around 300,000 years ago.
They were later joined by humans, who entered Eurasia around 48,000 years ago.
Neanderthals were a cousin species of humans but not a direct ancestor – the two species separated from a common ancestor – who died about 50,000 years ago. Pictured is an exhibit from the Neanderthal museum
These were the original “cavemen”, historically believed to be dull and brutal compared to modern humans.
In recent years, however, and especially over the past decade, it has become increasingly evident that we have short-sold Neanderthals.
A growing body of evidence points to a more sophisticated and multifaceted type of “caveman” than previously thought possible.
It now seems likely that Neanderthals have told, buried their dead, painted and even interbred with humans.
They used body art such as pigments and beads, and were the very first artists, with Neanderthal rock art (and symbolism) in Spain seemingly predating early modern human art by around 20,000 years.
They are thought to have hunted ashore and fished. However, they became extinct about 40,000 years ago following the success of Homo sapiens in Europe.
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