Photo: Issouf Sanogo Agence France-Presse
This study suggests that systems of communication are influenced by the perspective of others would be appeared as soon as the first lines of hominoids.
Washington — chimpanzees living in the wild are capable of assessing danger and warn their fellow humans, especially those who appear to be unconscious, reveals a study published Wednesday in the american journal Science Advances.
For the first time, experience shows that animals take into account, when they communicate, the point of view of others, an ability thought to be unique to human beings, underline the researchers.
According to them, this suggests that the chimpanzees communicate and cooperate in more complex ways than we believed possible until then.
Experiences in Uganda
To test this theory, Catherine Crockford, a researcher at the Max Planck Institute for social anthropology in Germany, and his colleagues have designed a set of experiments in the Budongo forest in Uganda.
In particular, they have placed a fake poisonous snake on a path and observed how chimpanzees react to it, recording in a first time, how primates indicated to the other chimps where was the reptile.
In addition to cree, one-third of the chimpanzees pointed to the next, alternately, the whereabouts of the reptile and their congeners.
In a second experiment, the researchers tested two scenarios using calls pre-recorded chimpanzees launched to other members of their group.
In the first case, they have hidden a speaker to disseminate a cry indicating that a chimpanzee in the vicinity was aware of the presence of a snake, and another record indicating that another of these primates were not aware of the danger.
When the chimpanzees in the experiment have detected the serpent, those who had heard the cries recorded suggesting that one of their brethren had not seen the reptile started to throw up more warnings, cries and body movements, until he is out of danger.
Thus, the vocalization seems to change depending on whether the other chimps are, or are not aware of any danger.
Taken together, these observations suggest that the communication systems influenced by the perspective of the other, rather than by his own perception, arose from the first lines of hominoids, before the appearance of language, enter into these anthropologists.