 The call an individual uses varies as a response to the call that they've heard.If one of the contact calls is played over a loudspeaker (from a familiar location to the marmoset), the response from a given individual can be predicted, indicating that the calls are used as an identification mechanism of communication.Chacma Baboons have been observed to use contact calls not only as identification tools and locators of members of the group, but also as a way of communicating messages with one another about their status with respect to the main group.