The Cacajao, commonly known as the uakari, is notable for its bright red face and bald head. It inhabits the Amazon rainforest, particularly in flooded forests. This primate has a short tail, long limbs, and a diet consisting mainly of fruits and seeds. Uakaris are social animals, often seen in large groups.

The Cacajao, commonly known as the uakari, is native to the Amazon rainforest in South America. Their geographical distribution is primarily within the countries of Brazil, Peru, and Colombia, specifically in the Amazon Basin. They are typically found in the western Amazonian region, including areas along the Rio Negro, Rio Solimões, and Rio Japurá.

Cacajao species inhabit tropical rainforest environments characterized by high humidity, dense vegetation, and a warm climate with temperatures generally ranging from 24 to 28 degrees Celsius (75 to 82 degrees Fahrenheit). The annual rainfall in these regions is typically high, often exceeding 2000 mm (78 inches) per year, creating a lush and diverse ecosystem.

The uakaris are arboreal primates, primarily residing in the canopy and sub-canopy layers of the rainforest. They are well adapted to life in the trees, with strong limbs for climbing and long tails for balance. Their diet mainly consists of fruits, seeds, and occasionally small animals or insects. Uakaris are known for their strong social structures, often living in large groups, which aids in foraging and protection from predators.