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How does the structure of a cat’s vocal cords produce purring?

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Eurasian lynx (Lynx lynx) with tufted ears and spotted fur walking through snow in a winter landscape. — feline The Eurasian lynx (*Lynx lynx*), a member of the family Felidae, can be found in forests that range from Scandinavia to far eastern Russia. It is the largest member of the genus *Lynx* and the third largest predator in Europe.

It is a common misconception that purring is produced solely by the vibration of a cat's vocal cords. While scientists have not reached a definitive consensus on the exact mechanism, there are several prevailing theories regarding how cats produce this sound.1

One prominent theory suggests that purring originates from the laryngeal muscles in the throat. These muscles may cause the vocal cords to vibrate at low frequencies during both inhalation and exhalation, creating the characteristic rumbling sound. Other researchers propose that the sound is produced by the vibration of "false" vocal cords—membranes located near the true vocal cords—as they vibrate in the throat.21

Alternatively, some scientists believe the sound is not vocal at all, but rather the result of blood vibrating within a large vein in the chest. In this model, surrounding muscles repeatedly squeeze and release a blood vessel, with the lungs and windpipe acting to amplify the resulting vibrations.1

This ability is shared by domestic cats and other members of the Felinae subfamily, though it is notably absent in roaring big cats like lions and tigers.2