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 strangers in your dreams are actually people that you've seen in real life.
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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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If aliens located 60-65 million light years away from us, looked at earth through a really powerful telescope today, they would see dinosaurs!
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The University of Oxford (teaching since 1096) predates the Aztec empire (1428 - 1521).
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