A spider monkey is a New World monkey in the family Atelidae, found widely distributed across South America. These monkeys have long, spindly legs and lengthy tails along with slightly potbellied bodies, which remind some observers of spiders. They live exclusively in the rain forest, and are considered endangered due to habitat destruction. As a result, many zoos have established captive breeding programs in an effort to retain biodiversity and save the numerous individual species in the Ateles genus.
The average spider monkey ranges in length from 12-26 inches (35-66 centimeters), depending on the species and sex. The limbs and tail seem disproportionately long, and are used to move the monkey quickly and efficiently through the forest. Most never come down from the trees they live in, foraging for food and water in the rain forest canopy. Like other New World monkeys, spider monkeys lack opposable thumbs, although their prehensile tails are used like fifth hands. They have coarse hair in gray, brown, reddish, or black, depending on region and individual species.
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The diet of a spider monkey includes fruits, nuts, flowers, and greens, and the monkeys sometimes must forage far afield for food. Because of the large habitat that these monkeys require, they are especially sensitive to destruction of tracts of rain forest. Many scientists consider spider monkeys to be an indicator species, judging the health of the rain forest by the health of the spider monkey populations. These monkeys are also used in some scientific research, especially malaria research.
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In the wild, a troupe of spider monkeys contains around 20 individuals. The monkeys will break up into smaller sub groups for daily foraging expeditions, and they also appear to have a complex culture. Primarily, females are in charge of the group. In captivity, the monkey band is often smaller, but usually contains at least five monkeys so that they can retain the rudiments of their social structure.
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In some regions, captive spider monkeys are available as pets, especially in South America. Because of their endangered status, this practice is frowned upon by conservationists. Adult monkeys can also become quite strong and belligerent, and are not usually safe around children and teens.