Apes are once again proven to be man's closest relative, as scientists discovered young bonobos and children both manage emotions in a similar way, according to a press release.
Using this study, researchers can predict and test great ape behavior. It also adds another similarity humans have to apes, further establishing their evolutionary relationship. The study, published online Monday in the journal Proceedings of National Academy of Science, also shows the socio-emotional framework from young apes is the same as for children.
"This makes the species an ideal candidate for psychological comparisons," said Frans de Waal, Ph.D., of the Living Links Center at the Yerkes National Primate Research Center, Emory University. "Any fundamental similarity between humans and bonobos probably traces back to their last common ancestor, which lived around six million years ago."
De Waal worked with Emory colleague Zanna Clay, Ph.D. at a bonobo sanctuary near Kinshasa, the capital of the Democratic Republic of the Congo.
Video analysis showed the bonobos recovered quickly and easily from emotional troubles and were also empathetic to fellows who were down as well. Clay noticed the animals often used physical cues like hugging to comfort each other.
"Empathy allows great apes and humans to absorb the distress of others without getting overly distressed themselves," said de Waal.
Many bonobos victimized by bushmeat hunting reside in the sanctuary and young apes torn from their mothers are raised with a human substitute. When they are old enough, they are transferred to a forested enclosure with bonobos of all ages.
"Compared to peers reared by their own mothers, the orphans have difficulty managing emotional arousal," said Clay. "They would be very upset, screaming for minutes after a fight compared to mother-reared juveniles, who would snap out of it in seconds."
The researchers found that orphaned bonobos were perhaps emotionally scarred by growing up without their birth mother. Clay and de Waal noticed it took these young apes longer to recover from emotional trouble.
"Animal emotions have long been scientifically taboo," said de Waal. "By measuring the expression of distress and arousal in great apes, and how they cope, we were able to confirm that efficient emotion regulation is an essential part of empathy."
