It’s not just humans who are prone to hum contentedly while eating.
Chimps, bonobos and gorillas also murmur while masticating, and new research deciphers the sounds among western lowland gorillas in the Republic of the Congo.
The gorillas were observed eating 41 species of plant, 18 of which elicited the humming.
“Gorillas seem to hum and sing when encountering food they really like,” explained Simone Pika of the Max Planck Institute for Ornithology, Seewiesen, Germany, who led the study.
“This is very similar to our own behaviour when eating delicious food and emphasising this by also making ‘mmmmm’ sounds.”
The scientists say that the sounds could communicate a state of well-being in order to influence whether the group stays put or moves on. Indeed adult animals, and especially silverback males, were most likely to hum.
“It could be important for group movement, since silverbacks are the centre of the group and direct their movements,” Pika told BBC Wildlife.
Source PLoS ONE
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