There comes a point in the lives of young owl monkeys when they leave their parents and strike out on their own to find a mate. In a new study of a wild population of Azara's owl monkeys in northern Argentina, researchers reveal that a combination of social and ecological factors influences when these tree-dwelling monkeys peel away from their parents and siblings. According to their findings -- which were based on 25 years of genetic and demographic data for several generations of owl monkeys, covering more than 330 individuals -- none of the individuals, regardless of their sex, reproduced in the same group where they were born. In all cases, the researchers found, the animals either departed from their natal group or died before reproducing.