Laut Studie küssen und kuscheln Menschenaffen, um den Frieden zu bewahren – Berührungen, Umarmungen und Küsse vor stressigen Ereignissen könnten laut Wissenschaftlern, die das Verhalten unserer nächsten Affenverwandten untersuchen, eine uralte Methode sein, Vertrauen aufzubauen.

Abstract

Social tolerance underpins cooperation in humans and other social animals, but its proximate drivers in short-term, competitive contexts remain poorly understood. Reassurance behaviours may enable individuals to pre-empt conflict and signal benign intent, facilitating social tolerance. We tested whether reassuring body contact during anticipation of a collective feeding event promotes cofeeding tolerance in our closest primate relatives. Using a controlled cofeeding paradigm across five semi-wild bonobo and chimpanzee groups (n = 116 individuals), we quantified pre-feeding affiliative contact and measured access to a restricted, depleting food zone.

In both species, increased affiliative body contact enhanced subsequent cofeeding tolerance in most groups. Bonobo female–female pairs and chimpanzee male–male pairs engaged in more pre-feeding reassurance than other-sex pairings, aligning with species-specific predictions. However, these trends were only clear for socially tolerant groups. Likewise, vulnerable chimpanzee-specific kissing behaviours were more prevalent in a tolerant group. Our results reveal that reassuring contact may function as a flexible, short-term mechanism to mitigate contest competition and promote group-level tolerance. By identifying a proximate behavioural tool for managing competition in our closest cousins, our findings demonstrate the important role that friendly social behaviours play in negotiating the trade-off between competition and cooperation, as is essential to our own species’ survival.

https://royalsocietypublishing.org/rspb/article/293/2075/20253190/482572/Reassuring-body-contact-promotes-social-tolerance