When you have a cat, one of the most rewarding sounds he can make is purring. It's easy to associate that soft lull with a contented kitty, sleeping while you scratch his ears -- purring is actually a type of breathing, though, and it has more purpose than you think.
Making a Purr
Technically, purring is the side effect of muscle twitching that occurs independently of your cat's breathing. To break it down a little, your cat is always breathing. Obviously. When he purrs, it's because his brain is telling the laryngeal muscles to twitch -- and they twitch fast. So fast, in fact, that when your cat breathes while they are twitching, it separates the vocal cords with each breath, producing the gentle, rolling sound of a purr. Aww.
The Healing Factor
Purring isn't just a funny type of breathing, though -- it actually has benefits that you never really see unless you're looking for them. Chief among them is that purring can actually improve your cat's ability to heal himself, which is why sometimes cats purr right after giving birth or when they're sick. It's basically like an internalized form of physical therapy.
Cats may even purr to elicit an emotional reaction -- yes, your cat is willfully manipulating you. Remember, the impulse to purr starts in the brain and can be done at will. After centuries of domestication, many cats have developed an instinct to purr because it pleases their human masters. Your cat can sneak in a sad little cry, tucking it away in a purr where you will only notice it subliminally, triggering your nurturing instincts. The end result? Attention or food. Your cat knows what he's doing.
Learning to Purr
Not all cats can purr. It's a learned and developed behavior, and if you don't use it, you lose it. Just look at big cats, like lions and tigers -- their vocal cords don't allow them to purr. Meanwhile, cats that are smaller by comparison -- even wild ones, like bobcats -- can purr, but can't roar the way bigger animals do. When's the last time you heard your calico unleash a roar that can be heard a mile away? Fact is, cats learn to communicate in ways that suit their environment, lifestyle and interests.
Tom Ryan is a freelance writer, editor and English tutor. He graduated from the University of Pittsburgh with a degree in English writing, and has also worked as an arts and entertainment reporter with "The Pitt News" and a public relations and advertising copywriter with the Carnegie Library of Pittsburgh.