Why do Howler Monkeys Howl?

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The howler monkeys are found in the rainforests of South America. The deep howls of these monkeys echo around the forest at dawn and dusk. A bony box in the thick neck of these monkeys amplifies its howling calls. They make the noise to warn other howler monkeys to keep out of the family group's patch of forest, so that they can keep the food supplies there for themselves.

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