(Picture: Getty Images)
(Picture: Getty Images)

When it’s late and humans aren’t around, giraffes do something rather unexpected: they hum.

This behaviour had never before been documented until recently, when researchers recorded almost 1,000 hours worth of giraffe sounds by leaving their recording equipment in the enclosures of three European zoos overnight.

Poring through the audio, they came across an unusual low hum that the giraffes seem to have made at night.

And they don’t really know why the giraffes do it.

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They have suggested the hum is some sort of communication between giraffes in separate enclosures.

‘These patterns might provide suggestive hints that in giraffe communication the ‘hum’ might function as a contact call, for example, to re-establish contact with herd mates,’ the researchers wrote.


The other, far less glamorous possibility, is that the hum is the sound the giraffe makes when it’s asleep, just like snoring.

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