Vienna/Berlin – Elephants can communicate in the wilderness over great distances through sounds in the infrasound range.
They communicate in a frequency of just 20 hertz, a level so low that humans can hardly hear it.
But it’s still unclear how they produce these sounds. Do they create it similarly to humans and other mammals by sending airflow through the vocal folds?
Or is it a muscle vibration similar to a purring cat? With the help of international colleagues, Christian Herbst from the University of Vienna came to the conclusion that elephants communicate like humans by airflow.
The researchers, among them Roland Frey from the Leibniz Institute for Zoo and Wildlife Research in Berlin, examined the larynx of an elephant that died of natural cause last autumn in the Berlin zoo.
“We placed the larynx on a pipe and blew heated and dampened air through the vocal folds. We basically simulated a lung in the laboratory,” explained Herbst.
With a high-speed video camera, the researchers were able to view a movement of the vocal folds as well as audio recordings of the low frequency sounds.
Herbst and his colleagues concluded that the frequency range communicated through the elephant’s vocal folds ranged from that of echo sounder bats to that of a singing human.
The vocal folds are in the larynx and consist of the vocal muscle and vocal cord. They produce tones with the help of their position and tension.
“We have known for 150 years that the voice of a human is generated in the larynx. But you can’t really examine animals endoscopically,” said Herbst.
The researchers presented their findings in the magazine Science.