Chimps use their feet for gripping and swinging through trees, so it’s no surprise that human feet, made for walking, are shaped a bit differently than our closest relatives’. But some people, it turns out, possess a more ape-like foot than others.
Most of us have very rigid feet, helpful for stability, with stiff ligaments holding the bones in the foot together.
When primates lift their heels off the ground, however, they have a floppy foot with nothing holding their bones together.
This is known as a midtarsal break and is similar to what the Boston team identified in some of their participants.
The authors of a new paper asked nearly 400 visitors at the Boston Museum of Science to walk around barefoot on a special carpet that analyzed components of the participants’ feet. As expected, the BBC reports, most people had stiff feet, which help with stabilizing our bipedal bodies. One in about thirteen of the participants, however, had more floppy feet, pointing towards a bone structure akin to that found in fossils of 2-million-year-old human ancestors and closer to the bone structure of our primate relatives.
The researchers hope this anomaly in some modern humans may help them study how our ancient ancestors moved as well as figure out how we evolved the stiff, non-folding feet most people inherit today. Whether or not the more flexible feet bestow an enhanced ability to climb trees also requires further investigation.
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