The sound allows the animals to communicate over distances of up to six miles.

The low-pitched elephant calls, occupying a frequency range below 20 Hertz, may seem to have
little in common with human singing.

However, researchers have confirmed that both are produced in exactly the same way.

Experts had wondered whether, like a cat’s purr, elephant infrasound was generated by
muscular ‘twitching’ movements of the vocal cords.

This mechanism can produce ‘arbitrarily low’ frequencies, scientists revealed.

Instead, it came to notice that the elephant sounds are made purely by air being blown
through the larynx, or voice box, as in the case of a human singer.

“The elephant larynx constitutes a vibrating system that behaves in a fashion similar to
that known in humans and other mammals, showing that flow-induced vocal fold vibration
offers a physiologically and evolutionarily efficient means to produce the very intense
low-frequency sounds used in elephant long-distant communication,” the German researchers
wrote in a science journal.