Month: June 2023

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The short answer is, no, cats don’t always land on their feet. But they do have a remarkable knack for it. They start to develop the uncanny trait by the time they’re three-week-old kittens [7]! And it’s not just domestic cats–wild felines, even big cats like tigers and leopards, can do it, too [3]. Humans have been mystified by this ability for centuries, at least [4]. Most of us aren’t that graceful. Neither are our dogs, horses, guinea pigs, and other pets. So how do our cats land on their feet?

Born to Fall

Cats and many other felines are arboreal animals [3, 6]. This means that in the wild, they spend most of their time in trees. Arboreal animals obviously have to be good at climbing, but they also have to be good at falling [6]. It’s an inevitable danger of life in the trees. So cats have several adaptations to help them fall gracefully. Cats have a high ratio of surface area to body weight, so when they fall, they create a lot of drag and fall more slowly than many other animals [3, 6]. A falling cat instinctively spreads out their legs like a parachute to slow their descent even more [2, 6, 8]. Cats also have relatively long, muscular legs and springy joints that act as shock absorbers [3, 6]. But, of course, that only works when cats land on their feet. This brings us to a particularly complex adaptation, the aerial righting reflex.

The Aerial Righting Reflex

All creatures that live in trees have an aerial righting reflex [6]. The aerial righting reflex describes the ability of these animals to know which way is down while falling and to reorient their bodies to land upright [3-6]. Cats can even execute this maneuver while blindfolded [4]. Physicists and biologists conducted experiments by dropping cats (and sometimes other animals) under various circumstances for centuries, trying to understand how they did it [4]. Then in 1894, the French physiologist Étienne-Jules Marey used an early slow-motion photography technique to photograph a falling cat, finally revealing the series of precise twisting motions that cats use to turn themselves right-way-up [4, 5].

DO NOT TRY THIS AT HOME. My mother has admitted to trying the cat-dropping experiment on the family cat when she and my uncle were kids, and during my research I stumbled upon many online videos of people doing the same. I’m sure countless cats have survived such “tests” without injury, but it’s not worth the risk that something might go wrong this time, and your cat gets hurt.

For the aerial righting reflex, cats rely on the semicircular canals deep inside their ears [1, 4, 8]. These tiny, fluid-filled tubes are what many animals use to sense the pull of gravity and to maintain their balance, including humans. If a cat’s semicircular canals are damaged, they can no longer right themselves in the air, even if they can see their surroundings [4]. Using the information from these inner ear structures, the cat’s brain quickly establishes which way is up vs. down. Then they employ some physics.

Some Physics

The angular momentum of a spinning object is a function of its mass, the distribution of that mass, and its rotation rate. If no outside force acted upon the object, the angular momentum wouldn’t change. This is why a figure skater spins faster when they pull their arms tight against their body. They are decreasing the distribution of their mass, but their mass itself can’t change, so their rotation speed must increase. This is the principle behind how cats flip themselves around in midair. [4, 5]

The first step of the aerial righting reflex, then, is for a cat to arch their back, which for physics purposes separates their body into two rotating halves. Then they rotate their head to get their front half spinning and extend their hind legs. Tucking in their front legs causes their front half to rotate quickly. To conserve their angular momentum, their back half will start to rotate in the opposite direction around its axis, but with their hind legs stuck out, it rotates more slowly. Extending the front legs stops the rotation of that half of their body. The back legs catch up, and after about 1.5 seconds, kitty has turned all the way around to land on her four paws. [4, 5]

If you find that explanation hard to follow…me too. I had to read it about ten times and look at the diagrams in chapter seven of Falling Felines and Fundamental Physics to figure it out [4]. Looking at Marey’s photograph series and watching videos like the one below helped, too.

High Rise Syndrome

On the subject of cats mostly landing on their feet, I want to tell you about high rise syndrome. With the literal rise of urban life building taller and taller apartment complexes, cats and other pets sometimes fall off of balconies and out of windows [2, 3, 6, 8]. Cats have great survival skills, but nothing in nature equipped them to think about clear glass or twenty-story buildings [2]. They’re instincts evolved to climbs trees, not concrete jungles. Unfortunately, because cats are particularly inclined to climb and pounce at birds, they are also especially likely to experience these falls [2, 8]. The term high rise syndrome can refer either to the phenomenon of cats falling from tall buildings [8] or to veterinarians’ and researchers’ curious observation that cats tend to have better outcomes when falling from higher stories than lower ones [2].

The research isn’t entirely consistent, but there are indications beyond the anecdotal evidence of veterinarians that it might be true, at least sometimes [8]. The most dangerous falls are generally said to be between the second and sixth stories (20-60 ft or 6-18 m). A fall from the first story is hardly even a fall, especially for a cat. But why would they be in less danger about the sixth story? Experts believe that when cats fall from just a few stories, they don’t have enough time to complete the aerial righting reflex, so they may land in awkward positions that cause greater injury [2].

Of course, there is a height at which the benefit of the reflex wouldn’t be enough, but for obvious reasons no one has experimented to find out exactly what that height is. We do know that cats can survive thirty-story falls, often with severe injuries [2]. However, a 1987 study in New York City of cats brought to a veterinarian after falls from high-rises found that not only did 90% survive, but one cat that fell thirty-two stories suffered only a chipped tooth and a collapsed lung [6]. A study published in 2004 which looked at 119 cats that fell from apartment buildings and were brought to a clinic in Zagreb, Croatia, found that the most common injury was a broken leg [8].

Preventing Your Cat from Falling

The researchers in the 2004 study also found that younger cats fell more often which makes sense, because kittens and young cats are more energetic, more curious, and less aware of the world’s dangers [8]. They reported that 65% of high-rise falls happened in the warmest months, from April-September [8]. Other research has shown the same thing: the warm spring/summer season leads to more incidents of high rise syndrome [2, 8]. This happens because people tend to open windows and balcony doors when it’s warm out [2, 8]. So either keep your doors and windows closed or put screens on them, especially if your cat is a youngster [2, 8]! And always keep an eye on kitty if you let them go out on the balcony. Outside time is great, but that’s not a safe place for a cat to be unsupervised.

Works Cited

1. Alderton, D. (1992). Cats: The visual guide to more than 250 types of cats from around the world. Dorling Kindersley Ltd. London.
2. Becker, M. and Spadafori, G. (2006). Do cats always land on their feet? 101 of the most perplexing questions answered about feline unfathomables, medical mysteries & befuddling behaviors. Health Communications, Inc. Deerfield Beach, FL.
3. Bondi Vet. (n.d.). Why do cats always land on their feet? https://www.bondivet.com/promo/cats-land-on-their-feet
4. Gbur, G. (2019). The cat righting reflex. In Falling felines and fundamental physics. Yale University Press. New Haven, CT.
5. Kesten, P. (2018, June 1). Why do cats always land on their feet? Santa Clarita University. https://www.scu.edu/illuminate/thought-leaders/phil-kesten/why-do-cats-always-land-on-their-feet.html
6. Nasaw, D. (2012, March 25). Who, what, why: How do cats survive falls from great heights? BBC News. https://www.bbc.com/news/magazine-17492802
7. Sechzera, J. A., Folsteina, S. E., Geigera, E. H., Mervisa, R. F., et al. (1984). Development and maturation of postural reflexes in normal kittens. Experimental Neurology, 86(3), 493–505. doi:10.1016/0014-4886(84)90084-0
8. Vnuk, D., Pirkić, B., Matičić, D., Radišić, B., et al. (2004). Feline high-rise syndrome: 119 cases (1998–2001). Journal of Feline Medicine and Surgery, 6(5), 305–312. doi:10.1016/j.jfms.2003.07.001

Published June 11th, 2023