Whispering is a common strategy used by people to communicate with one or more people while simultaneously trying to avoid having others hear. Other animals have been found to lower the volume of their communications as well under certain circumstances, but never before has any primate other than humans been found to do so. In this new effort, the discovery was inadvertent.
The two researchers were studying cotton-top tamarins at New York’s Central Park zoo, hoping to learn more about the kinds of calls the monkeys make to one another under different circumstances. Prior research had found that tamarins are capable of vocalizing a wide range of noises. Morrison and Reiss were most interested in what are known as mobbing calls—sounds members of a group make to confuse or intimidate predators.
Read more at: Phys.org