Urine washing in urban robust capuchin monkeys (Sapajus sp.): The relation with visitors.

In primates, urine washing (UW) is a behavior in which individuals intentionally deposit urine on their bodies. Social and nonsocial hypotheses have been proposed to explain the adaptive function of this behavior. For capuchins, different functions have been assigned for UW, suggesting it as a flexible behavior, but studies have been mainly in captivity.