When our ancestors discovered the trick of consistently producing sharp stone flakes, it constituted a major… — Richard E. Leakey

When our ancestors discovered the trick of consistently producing sharp stone flakes, it constituted a major breakthrough in human prehistory. ...The modest flake... is a highly effective implement for cutting through all but the toughest of hides... the humans who made and used these simple stone flakes thereby availed themselves of a new energy source—animal protein.

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