Alouatta

Alouatta is a genus of New World monkeys in the family Atelidae, commonly known as howler monkeys. They are among the largest primates in the Americas and are especially noted for their loud vocalizations, produced by an enlarged hyoid bone that functions as a resonating chamber. These calls can travel long distances and are used to defend territory and maintain group cohesion.

Alouatta species are distributed across tropical forests of Central and South America, from southern Mexico to northern Argentina. They are primarily arboreal, spending most of their time in trees. They have prehensile tails that aid in grasping branches, and their bodies are well adapted to a largely folivorous and frugivorous diet. Leaves form a major portion of their intake, supplemented by fruit when available; the digestive system is adapted to processing high-fiber foliage.

Physically, howlers are robust, with fur coloration that varies among species and individuals. Sexual dimorphism is present, with males typically larger than females. They move through the canopy in slow, deliberate branches-to-branch locomotion. Group life is common, ranging from small to medium-sized social units that often include several females and one or more males. Vocal behavior is a hallmark of the genus; loud barks and howls are produced by adults, with duet calls between mates and coordinated group displays that establish territorial boundaries.

Conservation-wise, Alouatta includes multiple described species with varying statuses, from Least Concern to more threatened categories, depending on range and population trends. Habitat loss and fragmentation, hunting, and degradation of forests are ongoing threats. Taxonomic classifications within the genus are subject to revision as new data on genetics and morphology become available.