University psychologists show chimpanzees use gestures to maintain their social relationships

Posted on 4th October 2016

Chimpanzees vary the types of gestures they use, depending on who they are communicating with, according to a new study by two researchers from the Department of Psychology at the University of Chester.

One of the chimpanzees from the Budongo forest.
One of the chimpanzees from the Budongo forest.

Similarly to the way humans interact with each other, chimpanzees use a variety of gestures to communicate with other chimpanzees, with whom they have social relationships. The study, published in the Nature journal - Scientific Reports - shows that chimpanzees use different gestures to communicate with different types of social partners, just as people communicate differently with close friends and more distant acquaintances.

Dr Anna Roberts, a Visiting Research Fellow at the Department of Psychology, collected data on wild chimpanzees in the Budongo Forest, Uganda.  She said: “I discovered that when chimpanzees were communicating with other chimpanzees they had close social relationships with, they tended to use less intense visual gestures such as extending their arm. These appear to be effective when communicating with a smaller number of other chimpanzees at close proximity. In contrast, when communicating with less close social partners, chimpanzees used more intense auditory gestures such as drumming on a tree or shaking a branch. Using low and high intensity gestures has important health implications for these chimpanzees”.

Dr Sam Roberts, the co-author on the study and a Senior Lecturer in Psychology at the University of Chester, said: “We know that chimpanzees use a wide variety of gestures when communicating, but until now it has been unclear whether they use different gestures for different types of social relationships. Our study suggests that being able to use gestures in this flexible way helps chimpanzees meet the many challenges that arise from living in a large and complex social group. It also suggests gestural communication may have played an important role in managing social relationships as our hominin ancestors lived in increasingly large groups through the course of human evolution.”

Videos of all the chimpanzee gestures can be seen on the YouTube channel: Anna Illona Roberts. An example of one can be found here: https://www.youtube.com/watch?v=P1AhkFiqWNo

Reference to the paper: Roberts, A. I., & Roberts, S. G. B. (2016). Wild chimpanzees modify modality of gestures according to the strength of social bonds and personal network size. Scientific Reports, 6, 33864. doi:10.1038/srep33864