The result of the study, which was published in the scientific journal PeerJ. Bonobos have 28 different facial movements, which can be traced back to 22 muscle actions. Although this does not quite match the mimic diversity of humans, they are close to their closest relatives, the chimpanzees. The new method now allows direct comparisons between humans, chimpanzees and bonobos for the first time and sheds light on how facial expressions have developed over the course of evolution.
The project was led by Dr Catia Correia Caeiro from the University of Leipzig and the Max Planck Institute for Evolutionary Anthropology. The new technology is not only a breakthrough for behavioural research, but also a practical tool for animal keepers and vets. They can use the system to better assess the emotional state of the animals. Particularly exciting. The tool will be freely accessible and can also be used by people without prior knowledge. So perhaps the facial expressions of bonobos will soon no longer be a secret.
News from "Universität Leipzig" on 17 June 2025
