Aotus lemurinus, commonly known as the brown night monkey or owl monkey, is a small primate native to the tropical forests of South America. This species is characterized by its large eyes, which are adapted for nocturnal vision, and its soft, brown fur. They are social animals, often found in small family groups, and are known for their unique vocalizations. These monkeys are primarily frugivorous, meaning they mainly eat fruits, but they also consume insects and other small animals. Aotus lemurinus is an important species for studying primate behavior and ecology, as they exhibit interesting social structures and communication methods.