Why Do Cats Purr?
By Rolf Lampo
For as long as there have been domestic cats, possibly longer, one question
has come up time and time again - Why do Cats Purr? To this day, no one can
say for certain, but there are a number of popular theories.
Some are quite convincing, some are verging on the ridiculous, there are
even a few that go way past ridiculous and well into the crazy ramblings of
the stereo-typical feline obsessive. (...and I'm not talking about me with
that last one, despite what you may have heard!)
In this article we'll discuss some of the more popular theories - maybe
your own experiences can add to the already extensive volume of speculation
on the subject, if so we'd love to hear about it.
Purring to show contentedness.
We all know the scene. A cat curled up on a lap, enjoying a fuss and
purring away without a care in the world. Contentedness is the most likely
reason given by the general populous when asked 'Why does a cat purr?' - but
most cat owners realise there's more to it.
There are a number of other occasions when a cat can be heard letting out
a loud purr, so although contentedness may well be one of the reasons for
purring, there must be others too. This theory also doesn't fully answer the
question of 'why?'- Why would a contented cat have any reason to demonstrate
their contentedness?
This leads us to the second theory; maybe the reason they show their
contentedness in this way is their affection for those around them?
Purring to show affection
Cats will often approach their favourite people purring loudly and
proceed to nuzzle, nibble, drool and roll all over them, in a great show of
affection. Undoubtedly in this instance the purring is part of the
affectionate behaviour.
Although proof still remains elusive, it is fairly logical to draw the
conclusion that the purring here is an audible means of communicating that
affection, as if to say 'I love you'.
To show passiveness
Blowing the satisfaction theory out of the water, cats can often be heard
purring after a serious trauma, accident or injury. In fact it seems that
the more imminent death is the louder they will purr. This is certainly not
a show of contentedness or affection, and a much more reasonable explanation
would be to demonstrate passiveness.
The common thinking is that this might be a message to a carer translated
as 'please look after me', or to a predator saying 'please don't hurt me any
more'.
The healing properties of a Purr
My favourite theory, possibly because I'm an idealist or possibly because
it is the most scientifically explainable, is that purring has healing
qualities and cats take every opportunity to get a bit of healing.
Unlike the other theories, this one also doesn't preclude any of the
other situations in which you might encounter a loud purr.
Cats purr at a frequency of between 25Hz and 150Hz. Low frequencies such
as these have been proven to have strange effects on the physiology of most
animals.
Effects range from altering mood to the involuntary relaxing of muscles
to increasing the speed of recovery from an injury. One of the most
compelling effects is that some low frequencies can, over time, increase the
strength of bones.
It is well noted that cats are tenacious and tough little critters,
surviving illnesses and injuries that would have killed a human many times
over. They can fall from great heights or consume deadly poisons and recover
without showing any lasting effect.
One of our cats even seems to enjoy the odd meal of hazardous substances,
to the point that we now lock away anything we know to be toxic.
In conclusion
In conclusion, there are still no firm conclusions! All of the above
theories, and some others, certainly have some merit. My own feeling is that
purring has more than one purpose; these may include all of the theories
mentioned here and more.
Either way, purring is certainly an endearing quality and just one more
reason to love your cat.
