Human language is infinite – although it consists of only a very limited number of sounds. From them we can form words and put them together according to fixed rules into ever new sentences. Researchers at the Institut des Sciences Cognitives Marc Jeannerod in Lyon and the Max Planck Institute for Evolutionary Anthropology in Leipzig have now detected such grammar-like structures in chimpanzees for the first time. They report their results in »Nature Communications Biology«.
The scientists led by anthropologist Cédric Girard-Buttoz investigated three properties of language that form the basis for an inexhaustible vocabulary: sounds must be combinable with each other as desired. In addition, these sound sequences must be able to be strung together, just like individual words to form a sentence. All this should be done according to certain rules. Such a rule could be, for example, that a certain sound occurs especially often at the beginning of an exclamation. The team analysed almost 5000 images of 46 wild chimpanzees in the Taï National Park in the Ivory Coast. For the first time, they were able to observe all three properties of speech in a non-human animal. Some monkeys systematically lined up up to ten sounds to each other.
"Our results show that the verbal communication system of the chimpanzees is much more complex and structured than previously assumed," says co -author Tatiana Bortolato. In theory, the primates could express hundreds of different meanings through the combination of twelve loud. The anthropologists could not find out whether they actually exploit this potential in the current work, since they did not pay attention to the context in which the monkeys communicated with each other. This is exactly what you want to investigate in the future.
