The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
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Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
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An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
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It takes approximately 12 hours for food to entirely digest.
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Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
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Having sex can make a woman look younger and more attractive due to the release of estrogen and collagen.
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A man's beard grows fastest when he anticipates sex.
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Playing Tetris after a traumatic event can prevent the development of traumatic memories and reduce the chance of having flashbacks.
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