Have you ever been lying in bed trying to sleep
when the cat jumps up on your chest and starts, like, kneading you, getting all up in
your face rumbling like a Corvette and drooling into your mouth? And you're kind of
annoyed because, like, you don't love the taste of cat spit, and you have to get up early. And you're also like "Awww... that's very cute. This cat has genuine affection for me." Well, don't be fooled! Sheriff Fluffy is probably
happen to be cuddling you, but cats don't just purr when they're content; they also do it when they're in pain, giving birth and even dying. (INTRO PLAYING) The smaller members of the felidae family
including lynx, cougar, ocelot and domestic cat can purr. And they do it by pulsing muscles in their larynx and diaphragm. The resulting vibrations come in a
rhythmic pattern during both inhalation and exhalation at a frequency
between 25 and 150 hertz. And cats make all kinds of interesting sounds, hisses, growls, mews, meows and (CAT NOISE), which is one of my favorites; all communicating
specific feelings like "feed me" or "you better better recognize", while purring could mean "I'm so happy" or "Crap! I'm dying!" Since purring occurs in
such different emotional states, it's not considered a true communicative vocalization. Instead, it turns out, it's a
kind of self-medication. Veterinarians have long known that cats are quicker to heal than dogs; especially from bone trauma. It's not uncommon for distracted cats to
fall from upper level windows in a condition called the "high-rise syndrome." But what's incredible, is that these poor
broken cats have a 90 percent chance for survival, no matter how messed
up they are, in part because they have a built-in method of physical therapy. In
the late 1990s, Doctor Clinton Rubin of the State University
of New York and his colleagues discovered that exposure to low-level
frequencies helps build bone density, and a cat's purr falls exactly within that frequency
sweet spot. So it could be that cats' purring helps
cats heal and keep them healthy. And people
who have gone through physical therapy can attest to this. Sitting there purring beats the other
way to build bone density– actually moving around. Let's face it:
cats are kinda lazy, and purring may help take the place of good ol' fashioned
exercise. Other animals need to, like, run after
balls, or chase cars to maintain healthy bones, but a cat need only put up its
paws and purr! And those perfect hertz vibrations may
help humans too. Turkeys, rats and sheep strapped to vibrating plates at purr
frequency for 10 to 20 minutes a day showed a marked increase in bone strength. Researchers are now looking at how this technology could benefit astronauts who suffered bone density
loss under low gravity conditions in space. Maybe Canadians Jack and Donna
Wright, the dubious world record holders for most cats owned by one household,
should call NASA because they have 689 cats. 689! I was picturing a mountain of
cats, all in one enormous bean bag just rehabilitating visiting astronauts
with their positive vibrations. So crazy, it just might work! Also, who
cares? It's adorable! Thanks for watching this episode of SciShow. If you have any questions or comments or suggestions, you can find us on Facebook and Twitter, and of course, in the comments below. And if you want to continue getting smarter with us here at SciShow, you can go to youtube.com/SciShow and subscribe!
