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One thing that makes humans human is our fast-paced conversation ability. Now, scientists have found chimpanzees have a similar trait.

A recent study discovered that chimps also took rapid turns to speak – not with words, but with hand gestures – sometimes even interrupting each other.

This could point to “deep evolutionary similarities (with humans) in how face-to-face conversations are structured,” Cat Hobaiter from the University of St Andrews told the BBC.

On average, there is a short, 200-millisecond moment of silence between the end of one human’s sentence and the beginning of the other’s response. That’s about the duration of a blink – so short that the second speaker does not even process the last word spoken by the first one.

But there are variations among humans, mainly due to cultural differences. A 2009 study found, for example, that the Japanese have the fastest turn-taking pace with just seven milliseconds, while Danes needed about 450 milliseconds to speak up.

“We still don’t know when these human conversational timing patterns evolved and for what reason,” said lead researcher Gal Badihi.

However, observing the same behavior among some of our closest cousins paves the way toward finding out.

In their research, Badihi, Hobaiter and their team recorded 8,500 gestures from 250 wild chimps in five East African communities.

Most of these gestures meant quick orders such as “stop it,” “follow me,” or “groom me.” The range of turn-taking times among the apes was wider than the humans’ Japanese-Danish spectrum: “The gaps ranged from interrupting the signaler 1,600 milliseconds before they finished their gesture, to taking 8,600 milliseconds to respond,” said Hobaiter.

The scientists also observed that some communities had slower exchanges than others.

“Chimpanzees use gestures in almost every aspect of their life,” Badihi told the Guardian, explaining that gestures helped mitigate conflict and foster companionship, with grooming as the hottest topic of conversation.

The researchers hope further studies will establish the origins of this turn-taking conversational behavior, and whether it exists in other species, such as whales and dolphins.