Male howler monkeys are black, and females range from a brown to a light tan color. They have a large neck and a large lower jaw (containing the large hyoid bones), short legs, and a long, prehensile tail. All baby howler monkeys are born with brown fur, but the fur on the males eventually changes to black. These monkeys can grow up to 2 feet in height and can weight up to 16 pounds. The males are usually significantly larger than the females.
Howlers travel and live in packs of one to three males and two to seven females. There is one dominant male in each group. They spend the majority of their time in trees. Their howling vocalizations are used to mark their territories as well as to communicate with other packs of monkeys. Their diet consists mostly of leaves, but they also eat fruit and bugs. They are becoming an endangered species due to the shrinking size of the forests in which they live.
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