A form of communication in which the signal varies according to the type of object to which reference is being made. It is most commonly seen in alarm situations. A number of species, including chickens (Gallus gallus domesticus) and various types of monkey (Simiae), have been reported to give alarm calls that differ according to the type of danger. Adult vervet monkeys (Cercopithecus aethiops) give different alarm calls when they sight a leopard (Panthera pardus), a python (Pythonidae), or an eagle (Accipitridae). When they hear the alarm, the other monkeys take action appropriate to the predator that has been sighted. If it is a snake, they look down, and if it is an eagle they look up. If they hear the leopard alarm, then they run into the trees.
Subjects: Zoology and Animal Sciences.