With cries of a chimpanzee, humans are able to guess if the primate is attacked, discovers food or suffers a tickling session, according to a study published Wednesday in the journal Proceedings of the Royal Society B . "For the first time, we demonstrate that humans are able to deduce from vocalizations of other species, the behavioral contexts in which they were produced," explains Roza Kamiloglu of the University of Amsterdam, co-author of the study. .
To reach these conclusions, nearly 3,500 people, not experts in primates, were invited to listen to 150 vocalizations of 66 chimpanzees, then to determine if the animal was in a positive or negative context and if it was relaxed or excited . "The individual is in a negative situation when for example he is attacked by another chimpanzee, when he faces something frightening or is separated from his mother," explains Roza Kamiloglu. Tickling and good meals illustrate positive contexts. "Our results show that listeners are more able to deduce information from negative vocalizations than positive," notes the researcher, adding that "negative situations involve danger and can be more important for survival".
Relate a cry to a context
Among the participants, 300 then had to link the vocalizations to ten behavioral contexts defined by the researchers, according to whether they thought that the primate discovered food, was tickled or attacked by another chimpanzee, or if he himself threatened a fellow aggressive or a predator ... The others were asked to indicate whether or not the cry heard corresponded to a behavioral context. This for each context.
According to the study, "the results show that the listeners managed to match the vocalizations with most contexts". An aptitude due to the fact that we are "genetically closely related" to chimpanzees.