英語(yǔ)聽(tīng)力：自然百科 A Cat Has Nine Lives 貓有九條命

The cat's earliest ancestors probably hunted both on the ground and in the trees. To survive, they needed not only claws, but remarkable balance, an aptitude all cats retain to this day. In keeping with its reputation, the cat usually does land on all fours, and scientists have come to understand how. Slow-motion photography reveals that cats always right themselves in a precise order. The head rotates first based on messages from the eyes and inner ear. Then, the spine twists and the rear quarters align. At the same time, the cat arches its back to reduce the force of impact.

Despite its agility, the cat faces particular dangers in today's modern cities. Here although hundreds of feet above the ground, the indoor cat is just as attracted by moving prey as is any other cat. If any thing, it may be a stir-crazy bundle of energy. So many cats actually careen through unscreened windows that the phenomenon now has a name, high-rise syndrome. At the Animal Medical Center in New York City, doctors were perplexed when they found that victims of higher falls often had less severe injuries than those that fell a shorter distance.

It's been about a month since you were here, lad. We'd been puzzled by the high-rise syndrome for a long time, the name that we give for cats falling out of windows. A clinical impression is that cats that fall from medium-level stories are hurt much worse than cats that fell from even greater distances. That seemed to defy our logic that cats that would fall farther would be hurt less. So we undertook a study to examine the records on cats that had been admitted here for falling out of windows. And it actually confirmed that our clinical impression was correct. It seems that cats that fall from higher stories have enough time to reach free fall like a parachutist and are relaxed when you experience trauma when you are relaxed, you'll probably avoid injury; when you experience trauma when you are very rigid and very tight, you will attain a maximized injury.