Biologists have discovered how baleen whales produce their signature songs – and it includes their uniquely formed larynx.

Baleen whales, together with humpbacks, talk with complicated songs that may be heard over huge distances. “Folks recorded the primary whale sounds within the Seventies, nevertheless it was solely very lately that we began to understand the totally different sounds these animals really made,” says Coen Elemans on the College of Southern Denmark. “Now, the query is, how do they even do that?”

To study extra, Elemans and his staff extracted the larynxes of three lately deceased baleen whales: a sei whale (Balaenoptera borealis), a humpback whale (Megaptera novaeangliae) and a northern minke whale (Balaenoptera acutorostrata).

The larynx, generally generally known as the voice field, is an organ that sits on the prime of the neck in mammals. When air flows via the organ, folds of tissue vibrate, leading to sound.

However that isn’t the case with baleen whales, says Elemans. Upon examination of the whales’ larynxes, the staff discovered that they’d an sudden form – with a cushion of fats sitting on one aspect of the organ.

As these whales breathe, the air is pushed in opposition to the fatty materials, which causes it to vibrate and make sounds. “We’ve by no means seen this in every other animal,” says Elemans. “It’s completely distinctive to baleen whales.”

The whales can also recycle the air of their lungs, which is useful when they’re submerged for lengthy durations of time. After they breathe out via their windpipe and larynx, the air goes right into a sac with a contracting wall that expels the air again into their lungs.

From a pc mannequin of the larynx, the staff discovered that baleen whales may produce frequencies as much as 300 Hertz, at a most depth of 100 metres under the floor of the ocean. That’s throughout the frequency vary of noise made by ships, elevating issues that transport noise may drown out their songs.

“These whales can not escape this,” says Elemans. “So we want take steps to scale back the noise we make.”