Published on 29 Feb 2016
by Lorenzo Brenna
It seems that gorillas hum and sing to signal contentment and pleasure for the food they’re eating. Such discovery could shed light on how language evolved among our ancestors.
In the thick and verdant rainforests of Congo, curious, sweet and primordial singsongs are heard at dinnertime. They’re composed by gorillas. A new study shows that western lowland gorillas (Gorilla gorilla gorilla) sing and hum while eating.
These melodies represent their way of expressing satisfaction of what they’re eating. This form of communication is also used by leaders to announce it is mealtime to other family members. A similar behaviour was observed among other apes, including chimpanzees and bonobos, but aside from reports from zoos, there was no evidence of it in gorillas.
In order to find out if gorillas actually hum in the wild, Eva Luef, anthropological linguist, phonology and neurolinguistics expert at the Max Planck Institute for Ornithology of Seewiesen, Germany, tracked two wild western lowland gorilla populations in the Republic of Congo.
Gorilla in Congo
The researcher identified two different types of calls made by gorillas during eating. One of them was humming, a steady low-frequency tone that sounds a bit like a sigh of contentment, as Luef reported. “They don’t sing the same song over and over,” she said. “It seems like they are composing their little food songs.”
“Each gorilla has its own voice: you can really tell who’s singing,” said Ali Vella-Irving, who looks after gorillas at Toronto Zoo in Canada. “And if it’s their favourite food, they sing louder.” While every individual in the zoo sings for its supper, Eva Luef found that in the wild generally only dominant silverback males sing and hum while eating.
Gruppo di gorilla occidentali di pianura
It is thus thought that humming and singing is a way dominant males use to inform the group that mealtime is continuing and it is not yet time to move on. According to Eva Luef, this discovery could help shed light on how language has evolved in our ancestors.