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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The largest cell in the human body is the female egg and the smallest is the male sperm.
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We share 70% of our DNA with a slug.
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If Earth's life was compressed into 1 year, then humans would have been around for only 2 seconds.
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Your thumb is about the same size as your nose.
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Coughing can cause air to move through your windpipe faster than the speed of sound - over a thousand feet per second!
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A human brain produces as many as 12,000 to 50,000 thoughts per day, depending on how deep a thinker a person is.
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We forget why we have entered a room because passing through doors creates an ‘event boundary’ causing the brain to file away what we were just thinking about.
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