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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A group of kittens is called a "kindle".
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The sound of a tiger's roar can travel a distance of up to 2 miles (~3 km).
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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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Vampire bats adopt orphans, and are one of the few mammals known to risk their own lives to share food with less fortunate roost-mates.
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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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