Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
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Dolphins sometimes have fun by blowing bubbles and creating rings of air underwater, which they then swim through.
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Cats are one of the only animals to domesticate themselves and approach humans on their own terms.
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Some lizards, in which the tail is a major storage organ for accumulating reserves, will return to a dropped tail after the threat has passed, and will eat it to recover part of the sacrificed supplies.
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