Bonobos are comforted by bystanders when they emit “baby-like” signals to express their emotional distress

Psychologists at Durham University, UK, found in their study that bonobos produce a variety of signals, including “baby-like” signals, to strategically show distress when attacked by other bonobos.

The researchers conducted this study on two bonobo groups with over 40 bonobos in the Lola ya Bonobo Sanctuary in Kinshasa, Democratic Republic of the Congo, the world’s only bonobo sanctuary.

The researchers examined how bonobo victims communicate about their distress after a fight and whether these signals influence the reactions of bonobo bystanders. They found that when the bonobos send out certain types of signals of their emotional distress, they have higher chances of being comforted by other bonobos who are watching them. These signals are similar to those typically used by baby bonobos, such as B. Pouting, whimpering and tantrums.

The adult bonobos usually stop signaling their distress when supported by others, while immature bonobos still continue afterward.

The study shows that when adult bonobos display these “baby-like” signals after a conflict, they are also less likely to be attacked again by their former opponent.

The researchers further discovered that bonobos are sensitive to their audience, as they generally produce more signals when more bonobos in the social audience are nearby, suggesting that bonobos adjust their signals depending on who is nearby.

For a long time it was thought that great apes had no control over their emotional expression. The study results indicate that the expression of emotions is not only a reading of inner states, but can also be used flexibly and strategically in emotionally charged contexts to pursue social goals.

The full study was published in the journal Philosophical Transactions of the Royal Society B.

The lead author of the study, Dr. Raphaela Heesen of Durham University said: “Bonobos are very sensitive to social situations and their environment. They have rich emotional lives and are able to communicate their emotional states in flexible ways to influence their group members.

“Through targeted ‘baby-like’ cues, bonobos could increase their chances of being comforted by others and reduce their own stress levels following aggressive attacks in our own species, but also in our closest living primate relatives.”

The lead author of the study, Dr. Zanna Clay of Durham University said: “The act of comforting a victim in distress has long been viewed as a form of empathy initiated by the spectator. However, our study shows that the victim’s own signals can be used strategically to shape these responses.

“By producing signals that make them appear more like infants, bonobo victims may be more likely to receive comfort from others. This underscores the important role that communication plays in shaping empathic responses.”

The researchers emphasize that bonobos, like humans, have flexible ways of communicating their emotions.

The study illuminates the understanding of bonobos’ emotional life with a focus on the possible evolutionary origins of emotional communication.

This project was developed by members of the Comparative and Cross-Cultural Development Lab, led by Dr. Zanna Clay performed.