A recent study reveals that Bonovo call displays signs of complex communication

Constituity, the ability to combine meaningful elements into larger meaningful structures, is a characteristic of human language. Constitutiveness is trivial (the meaning of a combination is the sum of the meaning of that part) or non-trivial (one element changes the meaning of another element). In a new study, scientists studied the behavior of voices Wild bonobo (Pampaniscus) – Our closest living relatives – Kokoropoli Community Reserve The Democratic Republic of the Congo has found robust empirical evidence for the existence of non-trivial constitutive properties in these primates.

A distinctive feature of human language is its ability to combine individual elements to form more complex and meaningful structures.

This principle known as constituency allows morphemes to be constructed into words and sentences.

The overall meaning is determined by its components and their arrangement.

Constitutiveness can take two forms: trivial and non-trivial. In trivial composition, each word maintains an independent meaning.

Non-trivial constituency involves more complex and nuanced relationships where meaning is not merely a direct sum of words that involve.

Constituity may not be inherent to human language. Birds and primate studies have demonstrated that some animals can combine meaningful vocalizations with structures of trivial composition.

However, to date, there is no direct evidence that animals use non-trivial compositionality in their communication.

In their new study, Melissa Bursett, a biologist at the University of Zurich, and her colleagues, discovered strong empirical evidence that wild bonobos use non-trivial constitutiveness in their vocal communications.

The authors analyzed 700 recordings and call combinations of bonobo vocal calls and documented over 300 contextual features associated with each utterance

A linguistic framework that measures the similarity of meaning between words using methods derived from distribution semantics, and these contextual features were analyzed to infer the meaning of individual bonobo vocalizations and quantify the relationships.

Next, to assess whether Bonobo Call combinations follow construct principles, they applied a multi-step approach that had previously been used to identify the constitutive nature of human communication.

They found that the bonobo call types are integrated into four constituent structures. Three of these suggest that they share more structural similarities with human language than previously recognized.

“Our approach allowed us to quantify how the meaning of the combination of single-call and call on bonobos relate to one another,” said Simon Townsend, professor at the University of Zurich.

“Humans and bonobos had a common ancestor about 70-13 million years ago, so they share many characteristics through descent, and constitutiveness seems likely to be one of them,” added Martin Sarbeck, a professor at Harvard University.

“So our research suggests that our ancestors already use compositionality extensively, if not more, at least 7 million years ago,” Professor Townsend said.

study Published in the journal Science.

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M. Berthet et al. 2025. The broad composition of the Bonobos vocal system. Science 388 (6742): 104-108; doi: 10.1126/science.adv1170