Scientists have discovered that cat purring is a natural healing mechanism that probably created the legend that cats have 9 lives.

Wounded cats purr because it helps their bones and organs heal, say researchers who have analyzed the purring of different kinds of cats. This is why they can survive falls from high buildings. Exposure to similar sound frequencies is known to improve bone density in humans.

Cats? ability to survive and recover after falling from tall buildings is well documented. A study published in The Journal of the American Veterinary Medical Association found that out of 132 cats that fell an average of 5 ? stories, 90 percent survived, including one that fell 45 stories.

Scientists from the Fauna Communications Research Institute in North Carolina found that the normal purr frequency for a house cat was between 27 and 44 hertz, and 20 to 50 Hz for the puma, ocelot and cheetah. Lions purr, but tigers do not.

NOTE: This news story, previously published on our old site, will have any links removed.