We know cats purr for a variety of reasons. But the actual mechanics of how they make their signature sound remains unclear.

As the cat breathes in and out, vocal fold muscles in the larynx vibrate. This causes the small hyoid bones that support the larynx and the tongue to resonate, producing the familiar purr.

We think purrs are caused by the vibration of air through a cat’s larynx (voice box). The biggest cat species can't purr, but cheetahs and servals can. So why do cats purr and is it always a ...