Why do Cats Purr

We love to hear our cats purr. There is nothing better than a cat curled up on your lap, satisfied and happy, but have you ever wondered just how cats purr and why they do it?

Humans smile, dogs wag their tails and cats purr. All of us show our contentment in different ways. So it’s not surprising that when your cat is curled up beside you, or you are stroking them, they express their feelings by purring. However, purring is not always a sign of happiness. Sometimes it is an emotional response, indicative of pain or distress. Indeed, cats may purr while giving birth, so purring is more likely to be a mechanism that helps cats rest and repair.

Purring may be feline self-comforting behaviour. It is first expressed when kittens are only a few days old, perhaps signalling their presence to their mother, encouraging her to feed them. This form of communication continues into their adult lives.

How do cats purr?

What is most surprising is that cats have no special apparatus in their body to enable them to purr. Purring involves the rapid movement of the muscles of the larynx (voice box), combined with movement of the diaphragm (the muscle at the base of the chest cavity). The muscles move at around 20 to 30 times per second. 

As the cat breathes, air touches the vibrating muscles, producing a purr. Each cat’s purr is unique with some high pitched and others emitting a low rumble. Some purrs are so faint you have to be extremely close to your cat to hear it while others are extraordinarily loud.

The purr and meow combination

Cats have a special type of purr that they use when they want our attention, especially when they wish to be fed. This purr is known as a ‘solicitation purr’ and involves a combination of the purr and meow. Cat owners respond to this sound in a similar way that parent’s respond to the cry of their baby.

This is a wonderful example of how our domesticated feline friends have evolved to live with and be nurtured by us.