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Answers to The Question: Why do Cats Purr?

Answers to The Question: Why do Cats Purr?

Posted by Andrea on 6th Sep 2021

In order to answer this age-old question, we must go back to the evolution of the feline. Purring must have offered a selective advantage, or it would have disappeared over time. Many, but not all species of cats produce a “purr-like” vocalization that is most noticeable when the mother cat is nursing her kittens, or when the adult cat is being petted, stroked, or fed by his human companions.

Additionally, cats will purr when they are hungry, nervous, or in pain. So evidently, there are more complex physiological reasons to consider. Perhaps, it is in these stressful moments that we can find the key as to why cats purr. Whether it is a visit to the vet or recovery from an injury, cats will purr noticeably when their stress levels are high. Since these are the times cats are not happy with their environment or with their circumstances, this is the riddle that leads us to investigate the reasons behind why and how they purr.

One scientist purports that cat purring functions as a mechanism for internal healing. Other scientists have gone on to demonstrate that purring originates in the muscles of the larynx and the diaphragm. From this, it has been shown that cats purr both when they inhale and exhale--and with a consistent pattern and frequency in a range that can promote healing and improve bone density.

The association between the sound frequency of purrs with improved healing of bones and muscles might even prove helpful for people. It has been shown that the low-frequency vibrations of the purr correspond to certain sound therapy that has been successfully used to treat fractures, edema, and wounds in humans.

Since cats have evolved to conserve their energy during long periods of rest (a typical cat may sleep up to twenty hours per day), it is certainly possible that purring is a low-energy mechanism that stimulates muscle repair and bone regeneration without requiring much energy. Further, the durability of the feline, and his reputation for having “nine lives,” may show that purring and its regenerative powers are responsible for this enduring legend.

Moreover, since people generally respond so favorably to the cat’s purring as a soothing sound, it is not impossible that purring has evolved as a means by which domesticated cats chose to interact peacefully with their caretakers.

Since the domestication and breeding of cats has occurred relatively recently compared to dogs and other pets, it is fair to say that cats do not display as many muscle or bone abnormalities as do dogs, which have evolved much earlier. Perhaps the cat’s purring has helped felines to alleviate such conditions, and thus, these maladies are far more prevalent in their canine cousins.

Scientists believe they now know how purring happens. A “neural oscillator” in the feline brain triggers the constriction and relaxing of muscles around the larynx. So, perhaps it may not be too long until science hones in on the reason why this mysterious occurrence happens in the first place. The easy answer is just to accept that cats purr because they are happy. However, the better reason why cats purr is that purring is a method of self-healing in addition to a method of communicating with each other and with their human companions.

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