New research indicates that humans may not be the only species that expresses empathy. Elisabetta Palagi with the Natural History Museum at the University of Pisa in Italy and colleagues are the first to demonstrate both differences and similarities in a common empathetic response in both humans and bonobos. The research was presented in the Aug. 12, 2014, edition of the journal PeerJ.
The study is predicated on the fact that bonobos are the closet existing relative to humans. Genetic studies have shown a phenomenally large amount of DNA that is shared between humans and bonobos. The study also relies on the fact that yawn contagion has been observed in both humans and bonobos. Contagious yawning has been previously demonstrated to exist in both humans and bonobos that share a strong emotional bond.
The intent of the study was to determine the extent of the transfer of emotion called “emotional contagion” in bonobos relative to humans. Emotional contagion is considered to be one of the major foundations of empathy in humans. If bonobos exhibited the same rate and level of emotional contagion that humans do then bonobos could be considered to have empathy. The implication would be that emotional contagion is not a purely human behavior.
Bonobos were found to exhibit a form of empathy based on contagious yawning. The same scenario of an initiator or emitting face and a receiving face for the transmission of yawns between individuals was seen in both species. Humans exhibited a faster rate of transfer of yawns between individuals than did bonobos. This fact was attributed to human’s greater levels of cognitive abilities and memory retention.
The closer an individual was to another individual the greater the rate of contagious yawning and the faster the rate of transfer. Relationships were usually family or spousal in nature. The study does not indicate that bonobos exhibit all the nuances of empathy that humans do or the nuances of emotion that are involved with empathy. The research does indicate that empathy may be an evolutionary inheritance that has expanded as human’s mental abilities expanded.