Why Cats Purr: A Physiological Explanation

1 The Physiology of Cat Purring

I. Why Cats Purr

Cats have a special structure: like humans, the larynx divides into 3 parts, but the cat’s is special—the upper rear edge has false vocal cords and other structures. These make the false cords vibrate when breathing, resonating through the larynx to make the purr. This is the special nasal structure and the reason cats can purr.

So why this special structure?

1. A scientist exposed humans to sound waves at the cat-snore frequency and found it helped bone; so purring may promote bone growth and ease pain and heal bone injury—cats are jumpers and easily hurt.

2. Purring is an innate ability. After birth, the mother uses purrs to help kittens find her. About 5–6 days later, kittens answer with their own purrs. This low frequency eases communication and lowers predator detection.

But purring isn’t exclusive to cats—other felines like tigers and bobcats reportedly purr too. Why cats evolved it is still unclear. But purring cats are really cute, don’t you think?

II. When Do Cats Purr

1. Cats purr when happy, like our ‘wow’ when enjoying; they also purr on purpose when wanting something, rubbing against the owner to get attention, sometimes hoping for a pet—don’t think it can’t talk, it’s a little smartie!

2. Opposite: cats also purr when unhappy. But you can read mood from body language. Happy cats are relaxed and stretched, preferring good sightlines. Unhappy cats curl in a corner, licking themselves and purring, wary of surroundings.

3. As said, kittens purr while nursing to communicate with the mother; short-nosed cats purr more easily.

4. Also, respiratory disease causes purring, but lower and with noise—if so, take the cat to the vet promptly.

Above is our analysis of why cats purr; if you know more, we’d love your sharing!