Crows (and corvids, the family that includes crows, ravens, rooks and magpies) are extraordinarily intelligent creatures, but this means that they can be devious little devils, too. One annoying and clever behavior that they're all prone to is biting other, larger animals' tails and backing off when they try to retaliate, making them the supreme trolls of the animal kingdom.
This innate behavior, which has even been observed in corvids raised by humans, is thought to be a way to trick larger predators out of a meal. By teasing larger animals, corvids can steal scraps of their food, chase them away from a tasty carcass, or simply test their aggression.
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