Apes orphaned by the African bushmeat trade lack the social savvy of apes raised by their mothers, a new study finds. The study links the emotional development of bonobos (Pan paniscus), one of humans' closest living relatives, with the ability to interact nicely with others, echoing how human emotions develop.
Bonobos who are good at soothing themselves out of a bad mood are more likely to comfort other bonobos in distress, researchers report today (Oct. 14) in the journal Proceedings of the National Academy of Sciences.
"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," study researcher Frans de Waal, of Emory University's National Primate Research Center, said in a statement.
Though animal emotions "have long been scientifically taboo," de Waal said, he and his colleagues suspected that emotions might have evolved similarly before the bonobo and human lines split about 6 million years ago.