The Enigmatic Purr

Part Three:  The Anatomy of a Purr

The anatomy of a purr is shrouded in controversy. There are many diverse theories about how a purr is created. One theory is that purring is produced through a combination of the laryngeal, diaphragmatic muscles and a neural oscillator.  This theory probably makes the most sense because when a cat suffers from laryngeal paralysis, he can’t purr. Another theory claims that the vibrations come from the hyoid bone, a small bone located between the skull and the larynx. Still another veterinarian argues that purrs are initiated from the central nervous system. A long time ago people believed purrs were the result of blood rushing through the vena cava (large vein that carries blood to the heart).

Domestic cats don’t have the monopoly on purring, though they are one of the only animals who purr both while inhaling and exhaling. Servals, Cheetahs and Ocelots purr. Not all members of the Felidae Family purr though. Big cats that are members of the sub family Pantherinae are supposed to not purr. These include Lions, Tigers, Jaguars and Snow Leopards, along with other big cats. Though it has been reported that lions make a noise that may be kind of purr like. Other residents in the animal kingdom also purr. I read that Hyenas, Civet Cats and even Elephants purr.  I wonder if an Elephant really purrs. I would like to know in what circumstances these other animals purr. Does an Elephant purr when he’s feeling contented and safe? Does a Hyena purr when he’s stressed out? Is the mechanism behind these purrs the same as in our domestic cats?

I conclude my musings on purrs with more questions then answers…