[Eli5] How can animals stabilise themselves the always land on their feet?

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[Eli5] How can animals stabilise themselves the always land on their feet?

In: Physics

In much the same way you will always – so far as is possible – land on your shoulder with your arm thrown up to lessen the impact. This is as opposed to your head, say, or your legs.

Animals (including humans) have an inbuilt reflex to roll when they’re falling. That reflex will make them pivot at the spine and large joints to protect their most vulnerable parts. The way in which they pivot depends on their anatomy. Cats pivot their spine and tail to spin themselves around in order to land on their feet, because that is what will best minimise the damage from the fall for a cat. A human pivots their spine, shoulders, and hips in order to land on their shoulder, because that is the most robust part of a human when it comes to an impact. You arm and clavicle will break – they are designed to – and you will roll, and hopefully avoid breaking your neck, spine, ribs, or legs, all of which are potentially fatal injuries.

Cats are better at this. They don’t usually break.

Smarter Every Day did an interesting video where he breaks down the physics of what’s going on as best as he can based on the slow motion video he took of his cat being dropped upside down and then rotating to land on it’s feet.

[https://www.youtube.com/watch?v=RtWbpyjJqrU](https://www.youtube.com/watch?v=RtWbpyjJqrU)

The short/ELI5 answer is that a cat just has crazy fast reflexes. As soon as they’re dropped, they find the ground and twist their body around so their feet are pointed at it. They can also use their tail to help spin their body, much the same way that people will stick their arms out (or swing them around) if they lose their balance and start to fall.