How Do Cats Purr?

The way that cats purr has been a subject of great debate over many years, and cat experts still aren't in absolute agreement. Who'd have thought Kitty's purr could stir up such controversy in the scientific world?


At the moment, the most widely accepted theory to answer the how do cats purr question is that the voice box muscles rapidly twitch.
This causes rapid, repeated partial closing and opening of the middle of the voice box (i.e. the area where air moves through).


The repeated closing and opening causes vibrations in the air being breathed in and out. It's these vibrations that are responsible for making the purring sound.


The vibrations happen when Kitty breathes in and out, which is why the purr sounds continuous, as if he's not stopping to breathe at all!


The theory that Kitty's voicebox is responsible for purring is supported by the fact that cats that have paralyzed voice box muscles are unable to purr.


Why do some cats purr more than others?


I don't believe anyone knows the answer to this for sure, but it's thought that cats are a bit like humans... Some humans are very talkative, some whistle or sing all the time, others rarely or never do...


If you apply the same theory to cats, it's easy to understand why some purr more than others.


Do "big cats" purr?


Lions, panthers, tigers and leopards don't purr. But smaller "big" cats - e.g. cheetahs - do purr.






Source:  Cat Behavior Explained