A new study has just detected intentional communication in “nockers”, also nicknamed “sealing bread” monkeys: when a predator arrives, the females perform a specific alarm call, aimed at alerting the males to defend the group. A behavior never observed in any species other than humans, until today.
Just as we would cry “help” in case of danger, these female monkeys are able to give a precise warning cry when a predator is seen. This is shown by a recent study published in Animal Behavior Cognition, who looked at nodding monkeys, also called “sealing bread” or “white-nose” monkeys. These primates, characterized in particular by a white spot on their nose, hence their nickname, are mainly found in the west of the African continent.
The team of scientists set out to test 13 groups of rattlesnakes in the wild. “White-nosed monkeys live mainly in trees and live in groups of around 5 to 25 members”explains Dr. Claudia Stephan in a communicatedbiologist and first author of the study. “The male usually stays on the periphery of the group and barely participates in social interaction. » For each, a researcher dressed up in leopard skin and approached the group. The idea being to imitate the arrival of a predator. The females then made an alarm call, serving to alert the retreating males. “In order to prove that the females deliberately recruit the male in order to defend the group, we played recordings of the alarm calls of the males after the appearance of the leopard.continues Claudia Stephan. We wanted to show that the females react directly to the actions of the male to protect the group and not just to their calls. »
Currently, the origin of intentionality in human language is not known.
And the team found that this call adapted to the behavior of males, betraying intentional communication. More precisely, the females check the effect of their behavior, and therefore of their alertness, and then adapt it according to whether the objective has been achieved or not. A real first in the animal kingdom, because if this behavior exists of course in humans, it had never been observed in other species. “Until now, we had no conclusive evidence that intentionality of this type is also found in animal vocal communication”, confirms Claudia Stephan. This discovery could make it possible to go back to the evolutionary roots of the intentionality of human language, which remain for the moment unknown.