White-eared titi the males. There is a strong bond between the adult mating pair, they stay close and carry out activities together. Either member of the pair may follow the other and leadership changes through the day. Evidence of the strength of the pair bond is shown by grooming, huddling together with their tails twined, nuzzling, and gentle grasping. Titi monkeys are highly territorial and when confronted with another family group, both will respond with threatening behaviour, males showing increased agitation towards intruding males. When not close together, the pair show a significant amount of distress and agitation. Titi monkeys are well
Coimbra Filho's titi of Bahia and Sergipe in coastal northeastern Brazil. Coimbra Filho's titi, like most titis, is a folivore-frugivore, with a diet consisting mostly of leaves, but also including various fruits. Coimbra Filho's titi generally lives in small groups consisting of three to five members. Such a group generally contains a breeding pair and its direct offspring that have yet to reach sexual maturity. However, upon reaching sexual maturity, individuals leave their natal groups, and often immigrate to new areas. Their range size varies, with some occurrences recorded of ranges as small as , and others larger than . Coimbra Filho's titi