Cats are notoriously tough to comprehend. They are frequently regarded to be more elusive than dogs, despite their beauty. For some, though, this is precisely what makes life with cats so rewarding.
Jackson Galaxy, a cat behaviour and wellness expert, told Newsweek, "I enjoy living in the mysteries with them, you know?"
Why do cats purr is a question that has perplexed many cat enthusiasts for years.
Although cat communication is complex, most people who share their home with a feline will agree that a purring is a good sign that their animal is happy.
The reality, however, is much more complicated.
How Do Cats Purr?
The scientific community has been debating how cats are able to generate this sound. According to Galaxy, just as human-cat relationships can be enigmatic, science is equally enthralling.
"There [are] different hypotheses about when and why," he said when questioned about the origin of a cat's purr.
Blood flowing to the inferior vena cava was formerly assumed to be associated to purring until subsequent research revealed that the sounds came from the muscles within the cat's larynx.
"Laryngeal muscles in the throat open and close the glottis, which regulates the voice cords," explained Dr. Mikel Delgado, a scientist and cat specialist at Feline Minds.
"The movements induce air vibrations, which provide the purring sound. The brain is most likely signalling the muscle movements in reaction to pleasure and contentment."
Why Do Cats Purr?
While happy cats are more likely to make this vocalisation, it isn't the only occasion a cat will do so.
"Purring is regarded to be an intimate communication," said Lisa Stemcosky, proprietor of the PawLitically Correct cat behaviour consulting and Certified Cat Behavior Consultant.
"Only other cats or humans near the cat can hear it because the loudness is so low."
"Cats purr for a variety of reasons, but we believe the most important is to promote the mother-kitten relationship during nursing," Delgado concluded.
"That feel-good experience probably establishes purring as a response to comfort and pleasure in adulthood."
Cats can also purr at times of distress like when stressed, injured, or even at the end of their lives.
If you've ever found the sounds of your pet soothing, this is because they purr at a range between 25 and 150Hz. One study even suggested purring has healing properties.
As to whether this could be of any benefit to humans, Delgado explained: "There's no solid science behind this claim."
Stemcosky added: "Humans will always benefit from spending time with a purring cat, it's just good for the soul."
The reason we don't know exactly what causes cats to purr is that their sensitivity to their environment makes them hard to observe in a lab rather than their home.
What Is My Cat Trying to Tell Me?
Just hearing your cat purr is an indicator of a close bond as Stemcosky said: "It's very important, it relates to the intimacy of the relationship."
A more frantic purr, she added, is usually a sign that your cat wants something from you or another cat, like food.
"It seems like cats may use their purr to manipulate humans," Delgado agreed.
"A 2009 study suggested that cats can adjust their purr to sound more urgent to humans, especially when they want food."
Learning to understand the way your cat communicates with you requires some patience.
Delgado explained: "Cats can be subtle, and they can be quite individual in their likes and dislikes. Once you pay attention to their behavior and body language, it is not that difficult to understand your cat."
Feline body language is complex but to understand your cat you should pay attention to visual signal like the position of their ears, eyes, tail and whiskers.
Other important vocalizations to listen out for include meowing, chirping, hissing, growling and yowling.
Why Is My Cat Not Purring?
There are not always clear reasons why a cat may not purr but Delgado cited a 2017 study published in Behavioral Processes which found that cats with more behavior problems were less likely to purr, suggesting that a failure to purr may indicate that your cat is experiencing stress.
For Galaxy though, it comes down to the individual cat.
"This is all completely anecdotal but I wouldn't be worried... You know, your cat, if your cat was always like a purr machine, and suddenly they stop, then yeah, you should be concerned.
"If your cat has never purred before, and all of a sudden, is laying there and purring for no apparent reason. Again, you should probably be concerned, it's just knowing your cat."
