Song of the jungle Bernd Rohrschneider/FLPA

Gorillas sing and hum when eating, a discovery that could help shed light on how language evolved in early humans.

Singing seems to be a way for gorillas to express contentment with their meal, as well as for the head of the family to communicate to others that it is dinner time.

Food-related calls have been documented in many animals, including chimpanzees and bonobos, but aside from anecdotal reports from zoos, there was no evidence of it in gorillas.


To see if they make these noises in the wild, Eva Luef, a primatologist at the Max Planck Institute for Ornithology in Seewiesen, Germany, observed two groups of wild western lowland gorillas in the Republic of the Congo.

Luef identified two different types of sound that the gorillas sometimes made when eating. One of them was humming – a steady low-frequency tone that sounds a bit like a sigh of contentment (listen to clip below).

The other was singing – a series of short, differently pitched notes that sounds a little like someone humming a random melody (listen to clip below).

“They don’t sing the same song over and over,” says Luef. “It seems like they are composing their little food songs.”

Ali Vella-Irving, who looks after gorillas at Toronto Zoo in Canada, says humming and singing is a frequent part of mealtimes there. “Each gorilla has its own voice: you can really tell who’s singing,” she says. “And if it’s their favourite food, they sing louder.”

Singing for supper

But although every individual in the zoo sings for its supper, Luef found that in the wild it was generally only dominant silverback males that sang and hummed while eating.

This suggests that as well as possibly signalling contentment or pleasure with the food – a sort of gorilla version of “om nom nom” – the activity might be the silverback’s way of informing the group that mealtime is continuing and it is not yet time to move on. “He’s the one making the collective decisions for the group,” Luef says. “We think he uses this vocalisation to inform the others ‘OK, now we’re eating’.”

Zanna Clay, a psychologist at the University of Birmingham in the UK, who has studied communication in bonobos, says it is interesting how food calls in different species reflect the different social structures of the great apes.

“We think food calls are a very social signal; it’s about coordinating feeding events with others,” she says. “So in gorillas you get the dominant male producing the calls, because he has to keep hold of all the females in his group.”

In the much more fluid chimpanzee and bonobo societies, in which individuals constantly make decisions about who they want to hang out with, they all get involved in dinner-time conversations.

Because there is so much variation in calls both between individuals and species, food calls provide a good way to study the origin of language, says Clay. “It gives a good insight into the origin of meaning in animal signals, and also the social pressures that might drive the flexibility we see in language,” she says.

Journal reference: PLOS One, DOI:10.1371/journal.pone.0144197

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