Chimpanzees in Uganda use leaf gestures in a variety of dialects to communicate with their group.
According to the study, a community of Chimpanzees will use their preferred form of leaf-modifying gesture, and neighboring groups can use different ones, so that each group has its own dialect.
Chimpanzees use gruntural communication to communicate with one another. Chimpanzees make up after fights by using gestures. There are many ways in which a gesture can be performed, from using the hands to touching another person.
Like plucking the petals off a daisy, leaf gestures can include modifying the leaves by tearing or ripping them with a distinctive sound. Almost all the communities of Chimpanzees studied from East to West Africa have these leaf-modifying gestures in common. Researchers have shown for the first time that leaf-modifying gestures can't be explained by differences in forest environment or genetics.
The different forms of gestures used by the two communities seem to have the same meaning. I think of the song 'you say Potayto, I say Potaato'; it's the same word, with the same meaning, but with a different pronunciation.
The cultural component of human and non-human animal societies is called a dialect. Chimpanzees have been shown to be very good at learning from each other, but scientists haven't found any evidence that their social environment affects their communication. Chimpanzees may learn some aspects of their communication from other animals.
"These gestures are quite common, but in the thick forest it can be hard to see the details," said Dr. Cat Hobaiter. We would look at the leaf remains after the chimps had said their last words. We were able to figure out who was using which style because of the different ways in which the leaves were torn.
Chimpanzees in Budongo use these leaf-modifying gestures for a number of reasons, but the most common one is as a sort of gesture called a pick-up line.
It appears that females who moved between communities were able to understand the dialect of their new community. Chimpanzees can learn to use foreign dialects even as adults.
The paper "Dialects in leaf-clipping and other leaf-modifying gestures between neighboring communities of East African Chimpanzees" was published in scientific reports.
There are Dialects in leaf-clipping and other leaf-modifying gestures between neighbours. The DOI is 10.1038/s41598-022 25814-x.
Journal information: Scientific Reports