Evolution Is Written in Our Joints

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Yesyou can say a lot about Homo sapiens of their joints. Above all, we see that our species seems anatomically unadapted to our way of life.

This lifestyle, of standing and walking on two legs unlike some of our primate predecessors, may have been key to enhancing the survival and reproductive advantage of our ancestral species. But oh, our joints – the parts of the body that do the heavy lifting to support this casual strategy – pay the price.

Knees hurt, ankles are sprained, hips break, and it doesn’t even let me start on my back. Each of us walks around in a body that still bears millions of years of mammalian non-verturie etched in the evolution of joints that have changed slightly to support a relatively recent bipedal existence.

Our spines, originally designed to serve as rafters under which hang an organ-filled stomach and chest, now act as columns to support the entire bipedal enterprise. “By being bipedal, we turned that spine vertically, a bad idea,” Dartmouth College paleoanthropologist Jeremy DeSilva once said. Nautilus editor Kevin Berger. “And to ensure that the torso is oriented over the hips and all of our joints are aligned and balanced, a curve is introduced into the spine.”

See? Unsuitable. Humans are one of the only mammals to develop scoliosis and other spinal problems, and approximately 60 to 80 percent of adults worldwide have suffered from lower back pain during their lifetime.

DeSilva then lamented the state of H. sapiens‘ foot. “If you were to challenge an engineer to design a structure that needs to be flexible enough to absorb forces from the ground, but stiff enough to be able to lift off the ground, and maybe even elastic enough to be able to absorb energy to push off the ground,” he told Berger, “the last thing they would do is make it from 26 parts.”

Guess how many bones are in the human foot?

This illogical construction is because we evolved from monkeys who made their living in trees. It takes all those foot bones to navigate a maze of branches and grab branches all day long. Not so much for walking to the corner store. “In evolving bipedalism, natural selection can only work with pre-existing forms,” DeSilva added. “He DIYed this monkey foot. I think it’s like using duct tape and paper clips to repair and stiffen this foot.”

Recently, researchers working in the crucible of human evolution in Africa shed light on how the construction of the ankle, in an ancestral species of hominids called Ardipithecus ramiduspoints to a model in which our species derives directly from a species reminiscent of today’s African apes, that is, tree-dwelling primates. A study published this month in Communication biology postulates that the age of 4.4 million years A. ramidus The fossil ankle has many similarities to the ankles of chimpanzees and gorillas that exist today.

Since scientists believe that A. ramidus walking upright, the authors suggest that it could be a true transitional species between arboreal and bipedal primates. The findings essentially shift previous interpretations of human evolution, where living apes such as chimpanzees and gorillas were considered evolutionary dead ends, to suggest that the species that form the link between upright humans and forest apes may belong more to the latter.

Either way, the reality we live in H. sapiens We have to deal with the fact that our joints will eventually fail, due to injury or age. As Bruce Latimer, director of the Center for Human Origins at Case Western Reserve University, once said: Nautilus on knees: “You take the most complex joint in the body and place it between two enormous levers – the femur and the tibia – and you’re looking for trouble. »

Of course. A ball and socket joint might work better than the hinge that is our knee, Latimer continued, but natural selection simply hasn’t had the time or impetus to adapt to all of the physiological challenges unique to humans—ultra marathon running, rugby, etc. – to which we submit them. “We didn’t need it,” Latimer said. “We didn’t know football.”

Main image: Svetolk / Shutterstock

• Bob Grant

  Published on October 22, 2025

  Bob Grant is the associate editor of Nautilus.