Nine lives of cat
(The exploration made by J. Diamond from the “Natural history” magazine)
I have never climbed to Empire State building and I wasn't going to do that. I have climbed the Eiffel tower in the elevator with great difficulty: with closed eyes and taking my wife's hand. Upstairs I tried to be as for from the edge of balcony as I could. In the apartments of Manhattan hotel I left my legs failed after the first glance out of the window. Such senses are close to everybody who suffers from altitude fear. Of course, my acrophobia is too strong but most of people fear the fallings because it is dangerous. Death after falling takes one of the leading places in the USA. In the country near 13 thousand similar accidents happen. And it is the most spread reason of death among children before 15 years old. Every fifth child's death in New York is a result of such accidents. You may break the bone just because of slipping on the stairs but there are almost no chances after "jumping" from 20 meters. Practically nobody who had fallen from the 6th floor on the ground did not survive.
There is nothing unusual that suicides prefer to jump from the high places. It, perhaps, is the most sure way. If you take the narcosis you may feel sick; if you push the trigger your hand may shake; but if you have already jumped from the roof nothing would help.
On this matter cats and people show the great difference between each other. Cats are absolutely indifferent to altitude. They often survive after the jumping which would kill any man. It is not because they seldom fall. On the contrary in Manhattan where so many high buildings cats fall down more often because they play and follow each other on roofs. Even in my native Los Angeles where so few sky-scrapers cats are often in danger to fall down from the window-sill during the earthquakes. People take fallen cats so often take to veterinary that in their terminology a new term arose: "altitude syndrome of cats".
In spite of such predisposition of cats to fallings there are fewer fatal results among them then among people. And the case is not only in that cats, unlike people, more adapted to fallings from 6-storey buildings. The more unusual fact is that cats survive in most cases of falling from the sky-scrapers. The champion here (at least in New York) is the kitten Sabrina which had fallen from the 32-th floor and almost didn't get any damage: it has just lost the tooth and scratched the chest. It's a paradox but the higher the building is the probably of death is less. The ability of surviving after such terrible fallings is the main fact that causes the legend about nine lives of cat.
Cat pasematology (from Greek "pasema" - "falling"), the science about fallings of cats, at first is not so interesting for you as such winning Nobel prize. But from the other side this science is valuable and each felofil (cat fan) understands this. Also it is interesting for medicine: to know the secret of cats would help us to reduce the number of accidents. More over, pasematology helps us to get knowledge in branches where the experiment would be inappropriate.
Let's begin from the facts, following the scientific tradition. Cat's syndrome of height was first described in 1976 by doctor Hordon Robinson, veterinary from New York hospital ASPCA. About 160 owners have brought fallen cats to him every year. The next important step was made by two veterinaries, doctors Wein Whitney and Sheryl Melhaff from Manhattan Animal Medicine Center 11 years after. During the only five-months summer-autumn period the number of cats, which had fallen from the window from the second floor and taken to the hospital, was 132. The most of them fell from the 4-6 floor. The maximum altitude was 32-nd floor (the famous Sabrina). Most of the victims fell to the pavement.
The damages that the cats had got were too different from which people got. In the most cases people die because of skull fractures or inner bleedings. After that comes broken spines or chests. But the most spread damage among cats is the nose bleeding. Standing on the top of the Eiffel tower with trembling legs and imagining myself laying on the pavement I thought the least of all about broken nose. Besides cats had got such damages as wounds of snouts, broken teeth, palates and low jaws, chest wounds.
Only three cats were with broken spines and four with broken ribs (that is often met among people). Like people cats often break their extremities but the picture of such fractures is not the same. Adult people more often break their legs, children break their arms, but cats break both the front and the back paws in the same way. (Try to explain this difference now without reading the article to the end).
It is strange but the chances among cats to survive grow together with the altitude: only 5 percent of them die after the falling from 6-31 floor and 10 percents die after falling from 1-5 floor. And we wouldn't ask the man who wants to throw you out of the window from the second floor to change it on the twentieth one to reduce the danger!
These are the facts. To understand such strange results let us ask the most serious physical analysis what can offer your modest biologist. Physics teaches that the result of falling is connected with it's speed, softness of surface, clash area and qualities of falling being: its weight, size, solidity, bone structure, joints and muscles.
9.8 m/sec is the acceleration of free falling. If body falls in vacuum its speed grows according to the rule of square root from the distance which had been done. After 32 floors you would get the speed of bullet (about 300 km per hour) and after two floor it would be only 50 km per hour. Just this fact explains my confidence that if I fall from the Eiffel tower the stain on the pavement would be more than the stain after falling from the upper stair. But the distance which the body had gone is not the only characteristic. The power of stroke is also connected with softness of surface because this characteristic shows the "breaking way", depth, on which you get into surface before you are stopping. The bigger this distance is the less power of strike would be. That is because pole jumpers put under the crossbar thick mat but not the concrete slab. For moderate fee (for example, $10000000) I would agree to jump from the roof on the soft and wide pillow. The stories about pilots, who had jumped without the parachutes but survived, are more about those fortunate men who fell into the swamp ("breaking way" is about 20 cm), then about those misfortunate of them who fell on the pavement ("breaking way" is a fraction of centimeter). To make the alternative to the soft surface you may wrap yourself with soft material. The fact that children survive more often than adults is partly connected with the action of under skin fat.
Theory says that attitude of the weight of falling body to its size is important because of two reasons. At first, the power of stroke is proportional to the weight. When my son Joshua, whose weight is 11 kg, jumps on my belly then it is a funny game. Hardly this game would give me pleasure when he is an adult and becomes 110 kg National football league forward. If to be more exact all these is expressed by the attitude of weight to area on which the stroke spreads.
The second point here is the resistance of the air. As we know Galileo thought that two bodies of different weights having being thrown from the Piz tower would get to the ground at the same time. It is absolutely correct concerning vacuum where the resistance of the air doesn't disturb the acceleration. As for the bodies which are falling in the earth atmosphere the more their size and less weight, the less their maximum speed and the quicker it grows. Just this fact is the main principle of the parachute and that is why feather falls on the ground more fluently than cannot kernel.
Now let us try to explain these physical principles like the reasons of the differences of damages after fallings among adults, children and cats. The attitude between weight and area grows together with the size of body. So we strike on the ground stronger than cats even if our bodies are alike and the pose is the same that doesn't happen in reality.
You may confirm that the bigger the body is the firm its bones will be. And that's why it will stand after the stronger strokes. But the difference is not so big that the situation could be changed. The danger to break the leg after the easiest falling among elephants is higher than among people: among adults it is the higher than among children and among children it's higher than among cats. Also cats have got one more unique advantage. They have the wonderful "gyroscope" which is situated in the inner ear. If the cat falls down with its back it quickly turns in the air with its paws down having been not flown even one and a half meter. As a result the stroke is divided in four paws. We, I mean adults, who have worse "gyroscope" can't control our pose during the falling. More often we land on two legs and less often on the head. Children have big head as compared with the other organs and they often fall with their head down instinctively taking their hands along. These facts cause typical damages: cats break their front and back paws but people more often break the skulls and arms (children) or legs (adults). Another one advantage of cats besides their light weight is that it can bend the extremities with the aim to divide the power of stroke among joints and muscles. If we are deprived of sensible "gyroscope" we should better imitate the cats to bend our legs reducing the power of stroke during the falling.
But even this advantage doesn't explain the most surprised fact that the chances of cat to survive grow if the altitude is more than the 6-th floor. We remind that bodies falling in the earth atmosphere accelerate to some maximum speed which is connected with air resistance (proportional to bodies area) and weight. After that their speed remains without changing before they change the weight and area. Of course, the weight can't change but the area which moves up to air stream can be changed. Parachutists during the free fly reduce the area and increase the speed, but stretching like the string, taking along the hands and legs they increase the area and reduce the speed.
Perhaps cats can do the same as parachutists can. Having not get the maximum speed they instinctively stretch their extremities which may be broken as a result. After getting maximum speed cats begin to feel accelerated power of gravitation and they may weaken taking the paws along like a squirrel-flyer. The resistance of air grows and spread on the whole body and the speed is reduced. Cat's ability to act like the professional parachutists explains not only its capability to survive after falling from the altitude of more than seven floors but also the big reducing of a risk to break paws. Most cats broke their paws after falling from 6-7th floors and only each thirteenth did the same after falling from the eighth floor or higher.
In general, falling cats have less risk in different ways than people. The little weight guarantees the less power of stroke, the less tension (power divided on the area) and the less maximum speed. All these qualities characterize many other little animals but cats nevertheless have less risk than the little dogs, for example. It is explained by some other advantages. Among them we may remind the beautiful "gyroscope" which helps cats to fall with the paws down but not with the head, bending of extremities which divide the press among the joints and muscles, and at least their ability to take the pose of squirrel-flyer after having been getting the maximum speed.
The knowledge in the area of evolution biology let think that the unique abilities of cats arose as the result of natural selection. The greater part of kinds of cats family and only some of dogs climb up the trees. During the millions years cats have been jumped on their prey from the trees and simply fell from tree. All of them, who had the bad "gyroscope", hard extremities and those who didn't study to take the pose of squirrel, died. Only the best "parachutists" survived. So cats must thank just this evolutional history for their nine lives.