Bonobo apes aren’t just grunting at each other — in fact, their complex ‘language’ offers plenty of surprises, scientists claim

Ape see, ape do.

Bonobos, humans’ closest relatives in the primate family, have a language of their own — and it’s not unlike the communication patterns of their upright cousins.

A new study published Thursday in the journal Science found that our evolutionary relatives can combine vocal sounds to produce phrases with new meanings in a way previously only observed in humans.

“Human language is not as unique as we thought,” said Melissa Berthet, a researcher at the University of Zurich who authored the report.

The team, led by the Zurich team alongside researchers from Harvard University, recorded and analyzed 700 vocalizations from 30 adult bonobos in the Kokolopori Bonobo Reserve in the Democratic Republic of the Congo, comparing their communications patterns to a list of 300 possible situations or descriptions.

This study “will change the face of the field,” Maël Leroux, an evolutionary biologist at the University of Rennes, who was not involved with the work, said in a statement to Science, calling their findings “pivotal.”

“[It’s] compelling evidence for abilities that were assumed to be uniquely human.”

In the human language, Berthet and her colleagues explained, words are often put together to make phrases that either mean simply the sum of their parts or mean something related to but not directly each component of the phrase.

The research found that the giant apes have seven different types of calls used in 19 different combinations. Of these combinations, 15 require further analysis — but four of them seem to follow the same rules as human sentences.

When bonobos yelp, it’s thought to mean “let’s do that,” while grunts are thought to mean “look at what I’m doing.” When combined to make a “yelp-grunt,” it seems to take on the meaning of “let’s do what I’m doing.” This combination reflects the sum of its parts, the researchers said, and bonobos used the phrase to encourage their fellow apes to build night nests.

The other three combinations, however, took on a meaning that was seemingly related to, but different from, their individual meanings.

A peep from a bonobo is believed to mean roughly “I would like to…” and a whistle is believed to mean “let’s stay together.” But when combined to make a “peep-whistle,” it’s thought to mean something along the lines of “let’s find peace” — a way to ease tensions in social situations such as during mating or displays of prowess.

The study authors gave another example of describing someone as a “blond dancer,” which uses sound to add to the meaning — the person is both blond and a dancer.

While various animal species can do this, it’s rarer and complex to describe someone as a “bad dancer.” To say someone is a “bad dancer” doesn’t mean that they are both bad and a dancer — it means they are bad at dancing specifically. This is something that researchers previously thought could only be done by humans.

The team of researchers said that these findings combined with previous studies involving chimps could be an indication of how language in humans involved, given that all three species have proved the ability to combine words and vocalizations to create phrases.

“The cognitive building blocks that facilitate this capacity is at least 7 million years old,” Dr. Simon Townsend, another author of the research, shared. “And I think that is a really cool finding.”