Jellyfish as a species are actually older than dinosaurs and sharks.
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Ants have tiny magnetic compasses in their antennae which help them navigate.
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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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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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Dolphins have names for one another.
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Early American humans hunted car-size armadillos and used their shells for houses.
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The colossal squid has the largest eyes in the world.
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