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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Cows can sleep standing up, but they can only dream lying down.
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Scientists at the Zhejiang University in China have developed an ultra-light material known as carbon aerogel.
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The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
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In Georgia, there is an airtight room called the Crypt of Civilization that was sealed in 1940. It contains numerous artefacts documenting what life was like at the time of sealing, and is scheduled to be opened in the year 8113 to show people of the future exactly what life was like.
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The University of Oxford (teaching since 1096) predates the Aztec empire (1428 - 1521).
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Scientists have revived a flowering plant from a fruit stored away in permafrost by Arctic ground squirrel 32,000 years ago.
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