It turns out that early human ancestors were handier than previously thought. A study published Thursday in the journal Science found evidence that Australopithecus africanus may have used tools more than 3 million years ago. The earliest stone tools ever discovered are from around 2.5 million years ago. Researchers did not uncover anything older. Instead, Matthew Kent, a paleoanthropologist at the University of Kent, and his team performed a CT scan on the hands of four A. africanus skeletons. The scan revealed spongy bone tissue in places where the hand faces the most pressure. In apes, that is often in areas used for gripping branches or walking on knuckles.
The internal structure of these hand bones — with support at the base of the thumb and the side of the knuckles — is unlike anything found in apes. It's more similar to the structure of human hands, meant for gripping tools. The finding is not conclusive proof that some of our earliest ancestors were using stone tools, but it does indicate that they had a "human-like" grip capable of doing just that.
IN-DEPTH
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