So I was thinking the other day, I says to myself I says: “how could purring possibly have evolved? What would have selected for such a complicated, albeit endearing, form of expression?” And self was all:
Yes, cats use purring to express contentment, but it turns out that cats purr during births, injuries, and severe distress as well as when blissed out.
Not just domestic cats purr by the way, any feline that doesn’t roar can purr. Cheetahs, cougars, ocelots, servals, and caracals can all do it, and some have evolved it independently. So what’s the big advantage?
Meanwhile, IN SPACE, astronauts muse that though they have the coolest job, they suffer a high price, mainly, bone density loss. And vomit that floats around. Anyway, because Neil Armstrong, et al have no gravity to demand simple resistance exercises like standing and walking, their muscles fall to disuse and bone density decreases. They’ve made specialized exercise machines, but i guess they aren’t working so well. What To Do?
Meanwhile, IN CATS, we’re noticing how ridiculously well cats heal themselves. Over 90% of 132 cats survived 5.5 story falls from apartments (point 5? damn you mezzanine!). Skin grafts and surgery recovery are extremely successful and speedy. Cats are healthier than dogs, they never seem to suffer from dysplasia or luxating patellas or other bone badnesses (bad to the). (Granted humans have been more obsessive about selecting for horrendous skeletal structures in dogs, see bulldogs, dachshunds, german shepherds, etc but even so, the statistics are impressive.) Why they so lucky?
Enter the scientists! Specifically Dr. Clinton Rubin, who put it together that healing and bone mass are both stimulated by vibration, and what do you know, purring in cats happens to fall within 25-140 Hz (Hz = Hertz = cycles per second) which is proven to be physically therapeutic. Most cat species have the perfect harmonics in their purr to contribute to pain relief and tendon repair.
But how do you prove that it’s the purring specifically helping the cats out? You can’t take the purr out of the cat to see what happens cuz it’s all related to the diaphragm n stuff, and the trauma to the animal would automatically disqualify your observations. and reserve your spot in hell.
Enter the…chickens? Apparently you don’t take the purr away, you give it to something else. Dr. Rubin stuck a bunch of chickens on a vibration plate for 20 minutes and then measured their bone strength.
Yep. Science ladies and gentlemen. Best. Subject. Ever. I wish someone would explain to me why chickens were the obvious choice for this exercise, though the hilarity of chickens bouncing around like popcorn in a box cannot be denied. (Of course the vibrations weren’t that strong, barely even visible).
And I don’t see how a plate is more accurate than strapping a cat to each chicken, but I suppose they knew what they were doing.
The experiment was repeated on rabbits (um, thank you, way more sense. Low to the ground, quiet, sane, mammals) and their bone strength increased 20%.
Then the rats came in, and things got really creative. They had three groups. Group 1 was prevented from using their back legs during the day. (i’m picturing those paralyzed dogs they attach little wheelchairs to. I so hope that’s how they did it, I would totally take a picture and put it on facebook)
Group 2 the same, except for 10 minutes each day they were allowed to walk around normally. Group 3 same, except they had 10 minutes of vibration therapy instead of exercise. Results?
Group 1 (no nuthin never) – 91% bone formation loss.
Group 2 (10 min exercise) – 62% bone formation loss.
Group 3 (10 min good vibrations)– almost no loss whatsoever.
This is all still controversial (you say one thing about chickens on vibrators and astronauts get all raised-eyebrow), but it could be that we can save those poor orphaned astronauts from breaking their legs upon re-entry to Earth by applying purr technology. And you thought it was just a small step for man….Sources: http://science.nasa.gov/science-news/science-at-nasa/2001/ast02nov_1/