Add Yahoo as a preferred source to see more of our stories on Google. Our prehistoric human ancestors relied on deliberately modified and sharpened stone tools as early as 3.3 million years ago. The ...
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Early humans relied on simple stone tools for 300,000 years in a changing East African landscape
Our prehistoric human ancestors relied on deliberately modified and sharpened stone tools as early as 3.3 million years ago. The selection of rock type depended on how easily the material could be ...
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