Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
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If a vampire bat goes 2 days without drinking blood, they can die. However, well fed female bats will puke up blood and share it with other bats that they like in exchange for grooming.
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Sheep, goats, octopuses, and toads have rectangular pupils.
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In Australia, there are spiders big enough to eat snakes.
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