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
Red-bellied titi whenever two from the same social group are by each other. The red-bellied titi has a variety of postures and facial expressions that it uses as visual signals. Swaying the entire body, turning the head sideways and lowering the head to face downward are examples of these signals. Observers have seen that these signals are a response to a disturbance or escape tendencies. Arching of the back is a signal that the red-bellied titi uses to warn that they're about to attack. This signal is associated with hostility, after they arch their backs an attack usually follows. Other signals associated