At some point in human history, our ancestors descended from the trees and started walking permanently on two legs. In the process, our feet evolved from the grasping appendages of other apes into sturdy levers. We lost an opposable big toe, our ankles became stiffer, and our bones formed an arch that runs from our ankle to our toes. We sacrificed the ability to grip in return for a springy, shock-absorbent step.
These changes were already in place 3.5 million years ago. One of our ancient relatives, Australopithecus afarensis, had a remarkably human foot and was clearly already walking around on two legs. Some scientists have taken this to mean that hominins such as Lucy (the most famousA.afarensis specimen) necessarily walked on the ground. After all, human feet are supposedly ill-suited for life in the trees.
But try telling that to the gentleman in the video below. He’s one of theTwa pygmies—a group of Ugandan hunter-gatherers who often climb trees in search of food, such as honey and fruit. Like other Twa men, he started from an early age. And he’s clear proof that a human foot is no impediment to walking straight up a trunk.
The footage was shot by Vivek Venkataraman, Thomas Kraft andNathaniel Dominy from Dartmouth College. The trio originally started studying the Twa to understand the evolution of their short five-foot stature but were awestruck at how adeptly they could climb. “We tried to climb the same trees, but we found it extremely difficult,” says Venkataraman. “The Twa were quicker, more agile, and highly coordinated.”
Written By: Ed Yongcontinue to source article at phenomena.nationalgeographic.com