Why do cats purr?

The gentle rumble of a purring cat is one of the most comforting sounds a pet owner can hear. Most people assume a cat purrs simply because it is happy, and while contentment is certainly one reason, the truth is far more interesting. Cats purr in a surprising variety of situations, including when they are frightened, injured, or even close to death. Scientists now understand that purring is a complex behavior that serves several different purposes, making it much more than a simple signal of a happy cat.

For a long time, exactly how cats produce the purring sound was a mystery. The current understanding is that purring comes from the cat's larynx, or voice box. A signal from the brain causes the muscles of the larynx to rapidly open and close the space between the vocal cords, many times per second. As the cat breathes in and out, air passing through this vibrating opening creates the steady purring sound. Because the mechanism works on both the inhale and the exhale, a cat can purr almost continuously without interrupting its breathing.

One of the most important functions of purring is communication. Kittens are born blind and deaf, and they begin purring when only a few days old, which helps them stay connected with their mother. Mother cats also purr, which may reassure their kittens and guide them during nursing. As cats grow up, purring continues to be a social signal. A purring cat may be telling a human or another animal that it feels safe and poses no threat. Some cats even develop a special "solicitation purr" with a higher-pitched, more urgent tone, which they use to encourage their owners to feed them.

Perhaps the most fascinating reason cats purr is that it appears to help them cope with stress and pain. Cats have been observed purring at the veterinarian, while recovering from injury, and even while giving birth. This suggests purring is a self-soothing mechanism, a way for a cat to calm itself in a difficult moment. Some researchers have also explored the idea that the low frequency of a cat's purr, often in the range of 25 to 150 hertz, may help stimulate healing in bones and tissue. While this healing theory is still being studied, it adds another intriguing layer to one of the animal kingdom's most familiar sounds.

This article was written using information from Wikipedia.