Overview
- The peer-reviewed study published Wednesday, July 22, 2026, analysed 60 controlled cofeeding sessions filmed in five semi-wild groups at two African sanctuaries and found a clear association between pre-feeding touch and later peaceful co-feeding.
- Researchers recorded 116 individuals during five-minute windows before food release and counted embraces, pats, hand-holding, genital contact and mouth-to-body touches to link specific reassurance acts to subsequent feeding tolerance.
- The effect varied by species and sex: female–female pairs showed the strongest link in bonobos while male–male pairs showed the strongest link in chimpanzees, matching each species’ core alliance patterns.
- Observers noted risky intimate gestures, such as placing fingers in another’s mouth, especially among tolerant male chimpanzees, which the team interprets as a likely signal of trust between partners.
- Authors emphasise the data are observational so causality is unresolved and they will next measure stress hormones and track pair-level behaviour over time to determine whether touch reduces tension or simply reflects pre-existing tolerance.