Last updated March 8, 2018 at 10:11 am
It seems chimpanzees and bonobos have a lot more in common than just looks and genes. They use many similar gestures during grooming and usually mean the same thing when they use them.
An international team has painstakingly defined the meaning of 33 bonobo gesture types and compared them with known chimpanzee gesture meanings. The overlap was quite substantial and, according to lead author Dr Kirsty Graham from the University of York, “may indicate that the gestures are biologically inherited”.
Chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) are the only two species in the genus Pan and are closely related, having separated about 1-2 million years ago.
Bonobos are a little smaller (they were once known as pygmy chimpanzees) and have slightly different facial features, but their genome is about 99.6 per cent identical to that of the chimpanzee.
In the recent study, researchers from the Universities of York, St Andrews and Kyoto defined the meaning of each of the bonobo gestures by looking at the reaction it elicited and whether the bonobo that gestured was “satisfied” with the reaction.
Once happy with these definitions, they compared them with the known meanings when the gestures were used by chimpanzees.
You can learn more from a set of videos included in the online Great Ape Dictionary.
But there’s still more of the story to be told.
“In future, we hope to learn more about how gestures develop through the apes’ lifetimes,” Graham says. “We are also starting to examine whether humans share any of these great ape gestures and understand the gesture meanings, so watch this space.”
The paper published in PLOS Biology.