While newborn kittens don’t have the ability to right themselves from birth, by the time they reach a few weeks old it seems that they’ve already developed what’s scientifically called the “air-righting reflex.” The ability therefore seems innate. But how, exactly, are cats able to achieve this impressive gymnastic feat? Like many easy questions, the answer is quite complex.
The first thing a cat needs to do when falling is to figure out which way is up. They do this in two ways – visually and using their inner ear. Experiments have shown that while cats that have one but not the other of these senses can still right themselves, if a cat is deprived of both, they fail to right themselves and land on their backs. This is true even if a kitten is blind from birth.
Cats taken on a parabolic flight, for science! Credit: okrajoe/YouTube.
Then it starts to get complicated. The basics are as follows: “When a cat falls, it tends to fold itself in half as much as possible and while it’s doing this it rotates the front half of its body to orientate itself so that it’s looking downwards. Then it pulls the rest of its body round with it,” Andrew Cuff, a postdoc researcher studying cat biomechanics at Royal Veterinary College, London, explained to IFLScience.
But how then, once it’s the right way up, does it manage to stop itself from over rotating and landing upside down?
You might assume that it’s all to do with the kitty’s tail, but as Manx cats – which don’t have a tail at all – can still right themselves, something else must be going on. It turns out that the cat folding to which Cuff refers is more than just a quirk. By bending itself in the middle and then doing different things with both its front and back ends – drawing in its front legs while extending its back ones – the cat increases the moment of inertia on the front, while decreasing it on the back. This has the effect of the front of the cat twisting at a higher speed then the rear.
Then, once its head is in the right position, the cat will extend its front legs, stopping that end from spinning, and pull in its back ones, tucking them in to twist. These opposite movements stop the cat from over-spinning. The kitty then points all of its feet down, extends its claws to make sure that it can grip when it hits the ground, and arches its back to slow its descent and to absorb any impact force. But these aren’t all of the adaptations.
“When it comes to the landing, the other parts that help are particularly to do with their shoulders,” explained Cuff. “Their shoulders are what we call free-floating, they aren’t connected to their spine or their ribs. They are able to move, they are completely mobile, with respect to the body, so when they land their shoulder blades can move around.”
So instead of having nine lives, they just have some clever adaptations instead.