Human evolutionary science has long been caught up in a debate: Did our last common ancestor with apes walk on its knuckles, like chimpanzees do, or was it more flat-handed? The answer to that question may lie in the anatomy of modern apes and extinct human species’ wrists.
The human-ape family tree doesn’t follow a straight path; it’s gnarled and branching. Scientists estimate it sprouted sometime between eight million and six million years ago, when an unknown ancestral species split into two lineages: nonhuman apes, such as chimpanzees and bonobos, and hominins, upright-walking primates such as Neanderthals, Denisovans, and anatomically modern humans.
In the absence of any fossil of this last common ancestor, it’s difficult for scientists to know what this creature may have looked like or how it behaved. While the search for such a fossil continues, some researchers have turned to other, less direct means of studying our ancient lineage, including fossils of extinct human “cousins” in the family tree, as well as the biology of modern humans and apes.
In a new study published on Tuesday in the journal Proceedings of the Royal Society B: Biological Sciences, researchers utilized both methods—they analyzed scans of wristbones from nonhuman primates such as gorillas, orangutans, and chimpanzees, as well as more than 50 hominin wristbone fossils. They found evidence that humans and our closest primate relatives—African apes—share wrist traits that may be related to walking on knuckles, although more research is needed to say definitively what a more ancient human species used those traits for, the authors say.
“There appear to be traits which evolved in the common ancestor of humans and African apes that, based on existing biomechanical research, could have been advantageous for knuckle walking,” says Laura Hunter, who conducted the research while a Ph.D. student at the University of Chicago. Some of the features include a “reorganization” of bones on the thumb side of the wrist in both knuckle-walking apes and humans, Hunter says.
A diagram showing seven of eight wristbones. (The eighth bone, the pisiform, is pea-shaped in humans and rod-shaped in nonhuman apes. It was excluded from the study for feasibility reasons.)
“Did Modern Human Carpal Morphology Evolve from Knuckle Walking Traits?” by Laura E. Hunter et al., in Proceedings of the Royal Society B: Biological Sciences, Vol. 293. Published online May 19, 2026
.
The study is “excellent,” says Tracy Kivell, director of the department of human origins at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who was not involved with the new research. While previous studies working to answer this question have focused on specific wristbones, this is “most comprehensive analysis of the wrist that we’ve seen yet,” Kivell says.
Hunter and her colleagues theorize that these shared traits may have “stuck around” in the human lineage through our evolutionary history not for knuckle walking but because they happened to also be advantageous for “object manipulation or sophisticated tool behaviors,” she says—a process biologists call “exaptation.”
There are some important caveats to the work. For one, the study is focused on just the wrist—it doesn’t reveal much about other parts of the body that may have been involved in knuckle walking or movement broadly, Kivell says.
The other wrinkle is that scientists can’t know for sure whether similarities between the human and ape wrists prove our common ancestor walked on its knuckles, if they were used in another wrist function, such as climbing, or if they are just a relic of our species’ relative proximity on the primate family tree. “I think we won’t ever know this answer until we find fossils from that time period,” Kivell says.
“I think it is important to emphasize that the title is a question, not a statement,” Hunter says, referring to the study, whose title asks, “Did Modern Human Carpal Morphology Evolve from Knuckle Walking Traits?”“There’s still a lot of work that definitely can be done to really figure out what exactly was happening with our ancestors,” she adds.
That’s part of the difficulty in studying fossils, Hunter notes—because the species are extinct, we may never know how our ancestors behaved.
“If only we could go back in time and see what they were doing,” she says.
In the world, human beings are facing various problems. People who are full of greed, anger, and ignorance are seen to be fighting with each other in words and deeds. As the fighting continues, various problems such as civil wars, wars of aggression, and wars of aggression are occurring. As world peace is being destroyed, humans are facing unbearable problems. Innocent children and women are not getting the rights they deserve and deserve. I can't think of one thing every time. What is it? The United Nations. If we look at the responsibilities and duties of the United Nations, I think it is not suitable for solving the problems that are happening in the world today. In fact, the United Nations and the World Security Council, such an organization must rule the world, must be able to give orders, and must have various ways to obey orders. There must be no organization that can influence more than that organization. There should be experts from each country. They can even dominate the superpowers like the US, China, and Britain. Only then will global peace be achieved quickly. Now, if a country with power develops more militarily, economically, or socially than its own country, then powerful countries will jealously seek out enemies and wage war. Or they will attack with fighter jets. In this, innocent people are losing their lives. No one understands the value of a life. You should think about how to achieve global peace by controlling these. If the US continues to be the permanent president of the UN, world peace will never be achieved. If you think carefully, no one sees that they are working for the common good, but for their own benefit, for the benefit of their own country. The permanent president of the UN and the Security Council has rejected this, As a young Rohingya, I have come to realize that only by electing the president and secretary from among the countries in the world through a secret ballot system and governing the world fairly can we achieve global peace. The United Nations and the Security Council are organizations in which any country must govern, give orders, and make them obey their orders. For example, only when a defendant is tried in court can we hold the leaders of the countries in check and control them, can we achieve global peace smoothly. Otherwise, it will not be easy for powerful countries to use various excuses to end this war every year, every year, for the benefit of themselves and their countries. No country's leaders pay any attention to the words of the United Nations and the Security Council. If we look at it in practice, look at the Rohingya issue. Myanmar is a small country. Even that country has been under siege for 8 years. What action can be taken? Why is the UN and the Security Council Powerless? Without such Power, how can the organization bring about global peace? Everyone should think about it. Whether there is a veto or a strong one, all countries in the world can only achieve global peace if they are subject to the UN and the Security Council. Seek peace in the quiet embrace of nature. Peace is an indispensable need of the human race. It is not as if one person can kill another person, and it is as if one country can attack another country, but instead of trying to build peace, we must try to destroy the peace now, and the world is getting hotter and is on the verge of collapse. I especially appeal to all the world experts to urgently try to bring about peace in all parts of the world. Mr, Noor Muhamed Arkhan Rohingya Youth Myanmar
Film and Writing Festival for Comedy. Showcasing best of comedy short films at the FEEDBACK Film Festival. Plus, showcasing best of comedy novels, short stories, poems, screenplays (TV, short, feature) at the festival performed by professional actors.
May 23, 2026 @ 18:34:26
Interesting read.
LikeLike
May 23, 2026 @ 23:37:34
Thanks for your comment sir! 👍 wouldn’t like to meet one and ask to see his knuckles.
LikeLiked by 1 person