Scientists have always assumed that, given their 13-foot-long tracheas, giraffes were silent beings. There has been some speculation that the gentle, odd-looking vegetarians might produce infrasonic sounds too low for the human ear to catch, but it’s never been proven.
At least, until now.
https://www.instagram.com/p/B2oquDZoCJI/
Researchers at the University of Vienna have spent the last 8 years gathering 947 hours of giraffe noises from zoos around Europe, and have come out with some very interesting – and unexpected – findings.
Not only do giraffes hum to each other at night, but they hum at frequencies that humans can actually hear (around 92 Hertz).
The report in BMC Research Notes, expands:
“Based on their acoustic structure, these vocalizations might function as communicative signals to convey information about the physical and motivational attributes of the caller.”
https://www.instagram.com/p/B2znYuojuji/
According to Wired:
“Giraffes have excellent vision, so their primary means of communication is thought to be visual signals during daylight hours. As prey animals, it also makes sense that they might not want to make loud noises that can attract the attention of predators. But when vision is impaired at night, low frequency humming might be a great way to make sure the herd stays together.”
More research is needed to correlate the sounds to giraffe behaviors, but scientists suspect the humming might convey information about age, gender, sexual arousal, dominance, and other things that are less understood.
Researchers more firmly believe that the sounds could be meant to keep the herd together at night, or help wanderers find their way back to safety.
Take a listen:
https://soundcloud.com/wired/giraffe-humming
It’s pretty cool, if you ask me. Were I a giraffe, there would be something reassuring about knowing the others would be there all night, making it easy to get some rest.
There’s safety in numbers, after all.
