It has been scientifically proven that stroking a cat can lower one's blood pressure!
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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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A cow produces around 200,000 glasses of milk in her lifetime.
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Cows can sleep standing up, but they can only dream lying down.
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Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
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The reindeer is the only mammal that can see UV light.
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Sergeant Stubby was the only war dog to be promoted to sergeant through combat in WWI. He saved his regiment from surprise mustard gas attacks, found and comforted the wounded, and even once caught a German spy by the seat of his pants, holding him there until American Soldiers found him.
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Penguins have a gland above their eye that turns saltwater into freshwater.
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