Interesting parallels to humans: Bonobos develop a kind of sense of duty towards their fellow species, suggests a behavioral study. If the great apes are interrupted in a joint activity, they then return to it with the same partner. In the event of a disruption or resumption of work, they also communicate particularly intensively using sounds and gestures. Bonobos may “apologize” in this way for interrupting the “binding” behavior.
Cooperation and mutual support are key elements of human success. It is well known that our complex social behavior is linked to many rules – those who do not adhere to them can expect negative reactions from other people. This system also includes the feeling of an obligation to others, which can appear in different contexts. It also shapes our behavior during joint activities or social activities such as engaging in a conversation. If people are disturbed – for example by an important phone call – the sense of duty is expressed, for example, in an apology for the interruption. After the end of the phone call, the partners then usually continue the interrupted interaction together.
Are bonobos also binding?
Is this behavior associated with the sense of duty exclusively human or do our closest relatives in the animal kingdom also show it? The researchers led by Raphaela Heesen from the University of Neuchâtel pursued this question in a study on 15 bonobos (Pan paniscus). They live in a very natural environment – in the “Valley of the Apes” – a zoological park in France. The study focused on grooming behavior – bonobos clean themselves as well as others. The social grooming could best correspond to the binding interactions in humans, explain the scientists.
In order to specifically interrupt partners in their mutual grooming, they each called one of the animals involved by name and gave it a treat. As a second variant of the disturbance, the researchers loudly opened the sliding door of the enclosure, which always caused excitement among the entire group of monkeys. The scientists recorded what happened before and after the disruptions using video recordings.
The evaluations of the behavior showed: In 80 percent of the cases, shortly after the interruption, the monkeys returned to the exact partner they had previously groomed and went back to work. If, on the other hand, they had cleaned their fur themselves beforehand, only about half of the animals continued their own personal hygiene after the disturbance. Accordingly, there is an increased commitment to the same behavior when a conspecific is involved, the scientists conclude. They see it as an indication of a kind of sense of duty on the part of the bonobos not to “let down” a partner, which resembles human behavior.
Special communication in the event of interruptions
The researchers also found that the animals show intense communication behavior when they interrupt and resume their work. What the monkeys are expressing remains speculation, of course, but it seems possible that the message is linked to the breach of binding behavior. In this context, the researchers also found that communication efforts depended on the ranking and social bond between the partners. “If you are in a meeting with your boss and your phone rings, you will apologize more clearly than if you were talking to a family member, for example,” explains Heesen. Apparently similarly, the monkeys tried harder when they were dealing with a higher-ranking animal, report the behavioral researchers.
“The bottom line is that our results indicate that bonobos have a certain awareness of the social consequences of interrupting a joint activity,” summarizes Heesen. The behavioral researchers now want to pursue this interesting behavior and the possible communication elements that accompany it. Perhaps this will give further indications as to whether the animals convey messages similar to humans: “Sorry, I’ll be right back” or “I’m sorry about the interruption”.
Source: University of Neuchâtel, specialist article: Science Advances, doi: 10.1126 / sciadv.abd1306