Why do cats purr?
When we stroke cats, they often purr. But how does this characteristic sound originate, and why do cats purr at all?
Cats purr as a means of communication, both with people and with other cats. The most familiar situation is when you stroke them in a place that they like. Cats also purr when they are washed by another cat. Moreover, the purring sound is often heard in connection with feeding – probably a relic from their first days of life, when the mother finds her kittens by means of the purring sound, allowing them to breastfed. In all these situations, the message is the same: keep doing whatever you are doing!
The purring can be heard when muscles in the larynx, which correspond to our vocal chords, contract and relax at fast intervals, making them vibrate. When the cat breathes, air passes the larnyx muscles, the vibrations of which set the air in motion, causing the sound waves we know as purring.
The sound is produced not only when the cat is comfortable, but also in very different situations when the cat is nervous, fearful or stressed, such as after having been chased by a dog. According to one theory concerning purring, it can have a reassuring effect on the cats themselves.
In 2001, cat purring in connection with stressful situations made animal sound researcher Elizabeth von Muggenthaler consider whether cats can even heal themselves with purring. She examined 44 cats, cheetahs, pumas and other cats, only to discover that the frequencies of the purring are consistent with the frequencies that exist in sounds and vibrations that are used in people to relieve muscle pain and boost bone growth.