Researchers create ‘dictionary’ for chimp sign language

Big news for anyone looking to have more meaningful conversations with man’s nearest genetic relative: For the first time, scientists at the University of St Andrews have decoded the hand gestures of chimpanzees. After studying some 80 animals, they believe they’ve translated everything from chest thumps to foot stomps.

“There is abundant evidence that chimpanzees and other apes gesture with purpose. Apes target their gestures to particular individuals, choosing appropriate gestures according to whether the other is looking or not; they stop gesturing when they get the result they want; and otherwise they keep going, trying out alternative gestures or other tactics altogether,” said Professor Richard Byrne.

After sorting through 4,500 instances of gesturing, they ascribed meaning to what they say are the 66 core “non-play” expressions chimps use to communicate. The non-play distinction is important because, as with humans, expressions used during play aren’t always used for their real meaning.

The full text is available by subscription, but Byrne and his colleagues provided a sampling of the communications. Tapping another chimp on the arm, for instance, usually means “stop that.” Hand flinging or slapping, as you might imagine, means “move away,” while an arm raise is used to say “give me that.”

Not unlike our human words, the same gesture can have different meanings depending on context. “Just as with human words, some gestures have several senses, but importantly the meanings of chimpanzee gestures are the same irrespective of who uses them. Chimpanzees may use more than one gesture for the same purpose – especially in social negotiations, where the final outcome may be a matter of some give and take,” explains co-author Dr Catherine Hobaiter.

There’s still much to be done, including research regarding variations of certain gestures and whether or not some are general rather than contextual. Still, we finally have an answer to what seems like an obvious question.

“It has been known for over 30 years that chimpanzees communicate in this way, but oddly enough nobody has attempted to answer the obvious question, what are these apes actually trying to ‘say’,”said Dr Byrne.