Overview
- Published in Science Advances, the Utrecht University–led study compared aggression in 22 zoo-housed groups of bonobos and chimpanzees.
- Observers recorded 3,243 aggressive incidents (1,368 in bonobos and 1,875 in chimpanzees), revealing no overall difference in aggression rates between the species.
- In chimpanzees, aggression was largely driven by males and directed at both sexes, whereas in bonobos aggression came from both sexes but was mostly aimed at males.
- Aggression levels varied widely between groups within each species, with bonobo groups showing both the highest and lowest rates observed.
- The authors say the results challenge simple self-domestication claims and point to aggression in the common ancestor of humans, chimpanzees, and bonobos, calling for more studies in wild populations.