Study finds great apes communicate cooperatively, like humans

The communicative exchanges of our closest living relatives, the great apes resemble turn-taking sequences in human conversation, a new study has found. Human language is a fundamentally cooperative enterprise, embodying fast-paced interactions. It has been suggested that it evolved as part of a larger adaptation of humans’ unique forms of cooperation, researchers said.

In a cross-species comparison of bonobos and chimpanzees, scientists from Max Planck Institute in Germany have now showed that communicative exchanges of our closest living relatives, the great apes resemble cooperative turn-taking sequences in human conversation.

Human communication is one of the most sophisticated signalling systems, being highly cooperative and including fast interactions, researchers said. The first step into this collective endeavour can already be observed in early infancy, well before the use of first words, when children start to engage in turn-taking interactional practices embodying gestures to communicate with other individuals, they said.

One of the predominant theories of language evolution thus suggested that the first fundamental steps towards human communication were gestures alone, researchers said. Scientists conducted the first systematic comparison of communicative interactions in mother-infant dyads of two different bonobo and two different chimpanzee communities in their natural environments.

The bonobos were studied over the duration of two years. The results showed that communicative exchanges in both species resemble cooperative turn-taking sequences in human conversation, researchers said. However, bonobos and chimpanzees differed in their communication styles. “For bonobos, gaze plays a more important role and they seem to anticipate signals before they have been fully articulated,” said Marlen Froehlich from Max Planck Institute.

In contrast, chimpanzees engage in more time-consuming communicative negotiations and use clearly recognisable units such as signal, pause and response, researchers said. Bonobos may therefore represent the most representative model for understanding the prerequisites of human communication, they said.

“Communicative interactions of great apes thus show the hallmarks of human social action during conversation and suggest that cooperative communication arose as a way of coordinating collaborative activities more efficiently,” said Simone Pika from Max Planck Institute. The findings were published in the journal Scientific Reports