Chimpanzees use distinctive drumming styles to communicate

Rainforest trees are supported by massive roots forming large flat buttresses. Male chimpanzees often drum with their hands and feet on these roots, sending messages that can be heard across over a kilometer through these dense, humid forests. Now, a team of scientists from the University of St Andrews has found that chimpanzees in Uganda’s Budongo Forest have their own signature style when drumming on these three roots. 

These specific rhythms allow the chimpanzees to send information revealing who is where, and what they are doing. Interestingly, only drumming activities performed while traveling appear to carry specific signatures, suggesting that chimpanzees can control whether they want to reveal their identity and location to conspecifics. 

“We could often recognize who was drumming when we heard them, and it was a fantastic way to find the different chimpanzees we were looking for – so if we could do it, we were sure they could too. It’s lovely to finally show how it works,” said study senior author Catherine Hobaiter, a primatologist at St Andrews.

“One thing that has always been a puzzle is why chimpanzees greet each other but very rarely seem to say goodbye. Our results might help to explain this – chimpanzees are rarely really out of contact, even when kilometers apart these long-distance signals allow them to keep in touch with who is where. It’s as though they have their own social media that allows them to check in through the day.”

The investigation revealed that chimps use different patterns of beats, with some individuals having a regular rhythm resembling that of rock or blues drummers, while others having more syncopated and variable jazz-like rhythms. They often combine these drums with long-distance calls, called “pant-hoots.”

“This really looks like chimp social media. Indeed, we also found that chimpanzees drum more often when they’re alone or in small groups. This means that they drum to know where others are and decide whether to join them or not,” said study lead author Vesta Eleuteri, a PhD student in the evolution of cognition and communication at the University of Vienna and visiting researcher at St Andrews. 

 “I was surprised that I was able to recognize who was drumming after just a few weeks in the forest. But their drumming rhythms are so distinctive that it’s easy to pick up on them. For example, Tristan – the John Bonham (Led Zeppelin) of the forest – makes very fast drums with many evenly separated beats. His drumming is so fast that you can barely see his hands! Ben, the alpha male, also has a peculiar style: he makes two closely following beats separated by one or two more distant beats.”

In future research, the scientists aim to investigate group differences to clarify whether there are different drumming “cultures” among different chimpanzee populations.

The study is published in the journal Animal Behavior.

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By Andrei Ionescu, Earth.com Staff Writer