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Turning round in mid-air

Why Does a Cat Always Land on Its Feet?

A falling cat has nothing to push against, and it turns over anyway. It does it by bending in the middle.

1 It startsupside down2 The body foldsin the middle3 It arrivesfeet first
No push, no ground, no help — and it still turns over.

  1. Step 1 of 5

    Falling means there is nothing to push against.

    The air abovenothing thereto push onThe cat itselfall it has isits own bodyThe floor belowarriving inabout a second
    The whole turn has to be paid for from the inside

    To turn, you normally shove against something. In the air a cat has no floor and no wall, so the usual way of turning is simply not available to it.

  2. Step 2 of 5

    So it turns the front and the back separately.

    Front, tucked in Light to swing —turns fastBack, held out Hard to swing — staysput

    The cat pulls its front legs in tight and lets its back legs stay out wide. The tucked end is easy to spin, the spread end resists, so the front swings round and the back barely moves.

  3. Step 3 of 5

    Then it swaps which end is tucked.

    1 Front spinswhile backholds2 The tuck isswapped over3 Back spins tocatch up

    Now the front legs go out and the back legs come in. The back end swings round to join the front, and the halves have each turned without the cat ever pushing on anything.

  4. Step 4 of 5

    A cat's spine is built to allow it.

    A spine that bendsfar furtherA collarbone thatfloats freeSo the two halvestwist apart
    The same floating sliver is why a cat fits through any gap its head clears.

    Its backbone bends much further than yours, and its collarbone is a small floating sliver rather than a bone strapped across the chest. The two halves of a cat can point in genuinely different directions.

  5. Step 5 of 5

    It needs height to finish.

    Too short to finishUnder about ametreLong enoughMore room thanit needs

    The whole manoeuvre takes a moment, so a very short drop can end badly — the cat runs out of fall before it runs out of turn.

    Landing is a separate problem. The legs bend deeply on impact to spread the stop out over time, which is the same trick as bending your knees off a wall.

The short version

A cat turns over in mid-air by tucking one end in and leaving the other out, then swapping — twisting each half in turn instead of pushing against anything.

Try it yourself

Sit on a swivel chair with your feet off the floor. Swing your arms out wide one way and tucked in the other way, over and over. You will slowly turn, with nothing to push on.

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