It is also known as the Night Monkey or Owl Monkey. They live in monogamous groups of a male, a female, and young. A young Night monkey will stay with its family for two and a half years.
Night monkeys are the only truly nocturnal monkeys.
They differ from most nocturnal mammals by having color vision and this, combined with the structure of their eyes, suggests that their ancestors were recently diurnal To avoid being hunted by diurnal hawks and eagles or being chased by larger monkeys from fruit trees, the Night monkeys have adapted to venturing out punctually fifteen minutes after sunset. Male Night monkeys who are searching for a mate or defending their territory will give a series of 2-4 short hoots.