

Interestingly, their attention was grabbed most by images showing conspecifics such as sexual behavior, yawning, or grooming, and not as much-as is often observed in humans-by signs of distress or aggression. As predicted, results consistently showed that bonobos' attention was biased toward the location of the emotional versus neutral scene. In the present study, we investigated (i) whether bonobos, similar to humans, have an attentional bias toward emotional scenes compared with conspecifics showing a neutral expression, and (ii) which emotional behaviors attract their attention the most. Bonobos have rich, social emotional lives and are known for their soft and friendly character. Humans tend to be biased toward emotional images, especially when the emotion is of a threatening nature. The dot-probe task is a well-established paradigm in psychology, measuring emotional attention through reaction times. In social animals, the fast detection of group members' emotional expressions promotes swift and adequate responses, which is crucial for the maintenance of social bonds and ultimately for group survival. Bonobos ( ) show an attentional bias toward conspecifics' emotions, Proceedings of the National Academy of Sciences (2016). The researchers suggest that their findings back up other observations of bonobos that has shown that bonding is an important part of their existence in their natural environment, where it is generally more important that individuals correctly read the emotions of others, than hostile actions by other species. Similar experiments run on humans and chimpanzees, the researchers note, have found that both species tend to react more quickly to images depicting danger or aggression. More specifically, they found that the bonobos were more focused on images of grooming, copulation, and most of all yawning, than on images of aggression or danger. In looking at their results, the researchers found that the bonobos located the dot more quickly when looking at pictures that showed other bonobos in an emotional state-and in general, a positive emotional state.

The experiment consisted of running 13 such tests in each session and 25 sessions in all. The purpose of the exercise was to determine which of the pictures that preceded the dot held more fascination for the bonobo. The bonobo got a treat after pointing at the spot. When the images were removed a single dot was shown in the spot where one of the pictures had been displayed. In this new effort, the researchers enlisted the assistance of four female bonobos, asking them to participate in dot-probe tasks, which consisted of sitting and watching as two images were projected onto a screen, side-by side. Because of their gentle good nature, bonobos have been the subject of much study, as we humans try to understand why we are so much more violent. Bonobos are also different from chimps and humans in that they live in a matriarchal-type society-the females run things. Bonobos are apes that look very much like chimpanzees, but unlike chimps, they are rarely aggressive, preferring to settle their differences by engaging in non-reproductive sexual encounters and other bonding experiences.
