A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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A newborn Chinese water deer is so small, it can (almost) be held in the palm of a hand.
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When Washoe, the first chimp to use sign language, was told that her caretaker's baby had died, she signed "CRY."
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The most expensive dog in the world is the Tibetan Mastiff; worth $1.5 million.
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Bats sleep 18-20 hours per day.
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A cow produces around 200,000 glasses of milk in her lifetime.
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Nervous dogs wag their tails to the left, and happy dogs to the right (from the dog’s point of view) – and fellow canines pick up on this lop-sided tail language.
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