A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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Queen ants have one of the longest life-spans of any known insect - typically up to 30 years. Western harvester ant queens can live up to 40 years!
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Sharks have been on the planet longer than trees.
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Penguins have a gland above their eye that turns saltwater into freshwater.
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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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