There has been plenty of research completed on how cats fall and how cats balance, what has not been done is research regarding on the science (impact, physical and mechanical, force, muscular-skeletal etc) of cats falling from a feeding pole in a captive state. The attachment above is from the book called "Think Cat" written by the late and legendary zoo vet David Taylor and is one of the best books around that explains in a simple non-scientific role on the science of cats.
BBC News - Who, What, Why: How do cats survive falls from great heights?
"Who, What, Why: How do cats survive falls from great heights?
A cat in a tree
Comfy? Cats are evolutionarily adapted to live in trees - luxury living with humans is a recent development
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A cat in the US city of Boston survived a fall from a 19-storey window and only bruised her chest. How do cats survive falls from such great heights?
The cat's owner Brittney Kirk, a nurse, left the window open a crack on Wednesday morning to give Sugar some air. Sugar got out and either fell or leapt off the ledge and hit a patch of grass and mulch.
An animal rescue service found her and traced her back to Ms Kirk through a microchip embedded in her skin.
"She's a tough little kitty," Ms Kirk told the Boston Globe newspaper.
Cats' remarkable ability to survive falls from great heights is a simple and predictable matter of physics, evolutionary biology, and physiology, veterinarians and biologists say.
"This recent story isn't much of a surprise," says Jake Socha, a biomechanist at Virginia Tech university.
"We do know that animals exhibit this behaviour, and there have been lots of records of these cats surviving."
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The answer
Cats have relatively large surface areas in proportion to their weight, so fall at a slower rate over a great height than larger mammals
Their bodies have evolved to allow them to survive falls from trees, their natural homes
Given the time, they twist to land on their feet
Their legs are long, muscular and extend under the body rather than straight down, allowing them to absorb the shock
But many cats who fall from heights are nevertheless severely injured and some die
Lucky cat survives 19-storey fall
With scientists unwilling to toss cats off buildings for experimental observation, science has been unable systematically to study the rate at which they live after crashing to the ground.
In a 1987 study of 132 cats brought to a New York City emergency veterinary clinic after falls from high-rise buildings, 90% of treated cats survived and only 37% needed emergency treatment to keep them alive. One that fell 32 stories onto concrete suffered only a chipped tooth and a collapsed lung and was released after 48 hours.
From the moment they're in the air to the instant after they hit the ground, cats' bodies are built to survive high falls, scientists say.
They have a relatively large surface area in proportion to their weight, thus reducing the force at which they hit the pavement.
Cats reach terminal velocity, the speed at which the downward tug of gravity is matched by the upward push of wind resistance, at a slow speed compared to large animals like humans and horses.
For instance, an average-sized cat with its limbs extended achieves a terminal velocity of about 60mph (97km/h), while an average-sized man reaches a terminal velocity of about 120mph (193km/h), according to the 1987 study by veterinarians Wayne Whitney and Cheryl Mehlhaff.
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This cat was lucky. But many, if not most, would have severe lung damage, would have a broken leg or two or three or four, maybe have damage to the tail, and maybe more likely than any of that a broken jaw or dental damage”
Steve Dale
Cat behaviour specialist
Cats are essentially arboreal animals: when they're not living in homes or in urban alleys, they tend to live in trees.
Sooner or later, they're going to fall, biologists say. Cats, monkeys, reptiles and other creatures will jump for prey and miss, a tree limb will break, or the wind will knock them over, so evolution has rendered them supremely capable of surviving falls.
"Being able to survive falls is a critical thing for animals that live in trees, and cats are one of them," says Dr Socha. "The domestic cat still contains whatever suite of adaptations they have that have enable cats to be good up in trees."
Through natural selection, cats have developed a keen instinct for sensing which way is down, analogous to the mechanism humans use for balance, biologists say.
Then - if given enough time - they are able to twist their bodies like a gymnast, astronaut or skydiver and spin their tails in order to position their feet under their bodies and land on them.
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WHO, WHAT, WHY?
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"Everything that lives in trees has what we call an aerial righting reflex," says Robert Dudley, a biologist at the animal flight laboratory at the University of California - Berkeley.
Cats can also spread their legs out to create a sort of parachute effect, says Andrew Biewener, a professor of organismal and evolutionary biology at Harvard University, although it is unclear how much this slows the rate of descent.
"They splay out their legs, which is going to expand their surface area of the body, and that increases the drag resistance," he says.
When they do land, cats' muscular legs - made for climbing trees - act as shock absorbers.
A cat lying down, from Thinkstock
Cats' legs are springy and muscular, letting them absorb the shock of impact
"Cats have long, compliant legs," says Jim Usherwood of the structure and motion lab at the Royal Veterinary College. "They've got decent muscles. In that they're able to jump quite well, the same muscles divert energy into decelerating rather than breaking bones."
The springy legs increase the distance over which the force of the collision with the ground dissipates, says Dr Biewener.
"The impact forces are much higher in stiff collisions," he says. "If they can increase the collision time over a longer period, that reduces the impact force."
And a cat's legs are angled under the body rather than extended downward, like human or horse legs.
"You're not transmitting the forces really directly," says Dr Socha.
"If the cat were to land with its legs directly under him in a column and hold him stiff, those bones would all break. But they go off to the side and the joints then bend, and you're now taking that energy and putting it into the joints and you're getting less of a force at the bone itself."
However, house cats in urban or suburban areas tend to be overweight and in less than peak physical condition, warns Steve Dale, a cat behaviour consultant who is on the board of the Winn Feline Foundation, which supports cat health research.
That detracts from their ability to right themselves in midair, he says.
"This cat was lucky," he says. "But many, if not most, would have severe lung damage, would have a broken leg or two or three or four, maybe have damage to the tail, and maybe more likely than any of that a broken jaw or dental damage."
and also:
How do cats survive falls from great heights? | Science-Based Life
"Recently, a small cat living in Boston survived a 19-storey fall from an apartment building. It was surely a bit of luck, but cats are evolutionarily adapted to survive such falls. Cats’ remarkable ability to survive falls from great heights is a simple and predictable matter of physics, evolutionary biology, and physiology.
From a great height
There are numerous accounts of cats surviving falls from seemingly deadly heights. However, as it is fairly unethical to test this ability by experimentally throwing cats out of high windows and seeing what happens, it has been hard to study this phenomena. Even so, by looking at the numbers of vet visits for such events, we get an idea of how successful a cat’s biology is at bracing a serious fall. Via the BBC:
In a 1987 study of 132 cats brought to a New York City emergency veterinary clinic after falls from high-rise buildings, 90% of treated cats survived and only 37% needed emergency treatment to keep them alive. One that fell 32 stories onto concrete suffered only a chipped tooth and a collapsed lung and was released after 48 hours.
It is pretty apparent from stories and reports like these that cats know how to fall effectively, but how do they do it?
The science of falling cats
First, cats have a high body surface area in proportion to their weight, reducing the pressure to their bodies when they hit the ground (because pressure equals force divided by area).
Second, because of their surface area and their low weight they reach terminal velocity, or the speed at which the pull of gravity is matched by wind resistance, much quicker than larger animals like humans. This means that they fall at a slower speed and subsequently hit the ground with less force. Again via the BBC:
For instance, an average-sized cat with its limbs extended achieves a terminal velocity of about 60mph (97km/h), while an average-sized man reaches a terminal velocity of about 120mph (193km/h), according to the 1987 study by veterinarians Wayne Whitney and Cheryl Mehlhaff.
Though we see cats usually living in someone’s house, cats are traditionally arboreal animals (they live in trees). Because sooner of later they are bound to fall, and any tree-dwelling animal will eventually pounce for prey and miss, cats are evolutionarily adapted to survive falls. That is to say, it is evolutionarily beneficial to be able to survive a fall, and as such modern house cats retain this ancestral adaptation.
Third, again through natural selection, cats have what is called aerial righting reflex which allows them to, given enough time, sense that they are falling incorrectly and spin themselves around like a sky diver or astronaut so that their feet are facing the ground. Having your main shock absorbers hit the ground instead of your back is crucial for fall survival. Interestingly, every animal that lives in the trees has a similar reflex, suggesting the same evolutionary process. You can see a shot by shot view of the aerial righting reflex below.
Fourth, cats also spread out their legs when they fall (as seen in the first picture above), increasing their surface area and slowing their descent by increasing the air’s drag on their bodies. Just how much this action slows their descent is unclear.
Fifth, cats have long muscular legs, adapted for climbing trees, that act as great shock absorbers. The same large muscles that allow them to jump many times their own height allows them to divert energy into decelerating them once they hit the ground instead of breaking bones. Because much of what is destructive about a collision is how rapidly a body decelerates, having long, springy legs allows cats to decelerate more slowly, thus reducing the seriousness of the collision.
WARNING PHYSICS CONTENT: For an example, think of an egg falling either onto a sheet held above the ground or onto pavement. In both cases the egg will come to a stop, meaning that the change in momentum (from some quantity during the fall to zero) is the same for both cases. However, because this change in momentum is dependent on the force applied to the egg and how long the force is applied to the egg, extending the amount of time the force is applied thus reduces the force applied.
So, why does the egg break on the pavement and not on the sheet even though the change in momentum is the same? The sheet is flexible and allows the time of collision to be extended, therefore reducing the force imparted to the egg. The pavement has an almost instant time of collision, therefore increasing the force and breaking the egg. You can also see this happening with your own body. If you jump to the ground from any height, you bend your knees upon impact, extending the time of collision and lessening the impact force. Learn more here.
Cats reduce the force imparted to their legs by having strong and springy legs in the first place. If cats landed from with their legs completely straight and rigid however, all of their bones would most likely break. Cat’s legs also have joints that can bend off to the sides of their bodies when they fall, unlike humans, which further reduces the force to their bodies.
Even given all of this adaptation, many house cats are estimated to be overweight and under-exercised and this reduces their ability to right themselves in mid-air and increases the speed at which they hit the ground. In all of their natural glory however, cats are purrfectly adapted to survive high falls.
The lesson from all of this? Cats that survive these incredibly high falls are lucky. Though many cats would survive, most would have severe lung damage, would have a broken leg or two or three or four, maybe have damage to the tail, and maybe more likely than any of that a broken jaw or dental damage. So put screens on your windows if you have a cat. They could probably handle a tumble from a tree, but an apartment building was never selected for."
And if you really want to read maths and physics:
http://pentagono.uniandes.edu.co/~j...inicursoJK-Uniandes/robotic examples/kane.pdf
