4 ms·

I’m not sure what they expected? Which way is a cat supposed to auto-right to in a weightless environment?

by xwdv 5y ago

ce4 5y ago
Probably the same reason as discussed here recently: A naked skydive inspired a way to keep pilots oriented in flight (military.com) https://news.ycombinator.com/item?id=30959126 https://news.ycombinator.com/item?id=30959126 Edit: Probably that submission led to this one.
teraflop 5y ago
But a cat free-falling from a height is also weightless, and yet they manage to right themselves using perceptual cues. The point of the experiment is to see how the behavior changes when the sensation of weightlessness is presented for an extended period of time, without the "falling" motion (relative to the perceived local environment) that normally accompanies it.
- ars 5y ago
  This is what most of the people replying here are missing - all falls are "free fall" (zero g). Yes the cat manages, but not in this situation.
  - NovemberWhiskey 5y ago
    The cat's system has memory. The transition into free-fall from a state where it was previously experiencing ground reaction force provides a cue for the self-righting reflex on the direction of "up/down". Apparently even blind cats can self-right based on their vestibular system.
moron4hire 5y ago
Any fall is a weightless environment, whether it's in a plane or off a building. But in a plane, you don't have the air rushing past your whiskers.
jstanley 5y ago
The cat might use visual cues to right itself. It might have been interesting to re-run the test with a more obvious "horizon" and see if the cats react to that. Then if the cat still doesn't right itself, it seems like it is using acceleration rather than vision to determine which way is down.
- nealabq 5y ago
  Do we know it's visual? If you drop a cat in darkness (onto a pillow of course), will it right itself? What if you put it in an elevator that accelerated downwards at 1G so the cat fell to the ceiling? How does it know which way is down? Is it the horizon, or the bright sky, or does the cat remember the scene before it was dropped? Or is it the air rushing by?
- cecilpl2 5y ago
  > Then if the cat still doesn't right itself, it seems like it is using acceleration rather than vision to determine which way is down. This is not possible because objects (including cats) in freefall do not experience the sensation of acceleration.
  - true_religion 5y ago
    Before a cat (or any object) experiences free fall, they experience acceleration so they know which way gravity is pulling them. Surely, a cat can remember what happened to it in the last few seconds and instinctually put its feet in that direction?
    - throwawayben 5y ago
      You don't feel any acceleration from gravity - it can only be determined from other senses like vision or the air flowing over your skin/fur
      - true_religion 5y ago
        What about inner ear sensations? Or the pressure of your organs pushing against one another?

I’m not sure what they expected? Which way is a cat supposed to auto-right to in a weightless environment?

by xwdv 5y ago

I’m not sure what they expected? Which way is a cat supposed to auto-right to in a weightless environment?

ce4 5y ago

Probably the same reason as discussed here recently: A naked skydive inspired a way to keep pilots oriented in flight (military.com) https://news.ycombinator.com/item?id=30959126 https://news.ycombinator.com/item?id=30959126 Edit: Probably that submission led to this one.

teraflop 5y ago

But a cat free-falling from a height is also weightless, and yet they manage to right themselves using perceptual cues. The point of the experiment is to see how the behavior changes when the sensation of weightlessness is presented for an extended period of time, without the "falling" motion (relative to the perceived local environment) that normally accompanies it.

ars 5y ago
This is what most of the people replying here are missing - all falls are "free fall" (zero g). Yes the cat manages, but not in this situation.
- NovemberWhiskey 5y ago
  The cat's system has memory. The transition into free-fall from a state where it was previously experiencing ground reaction force provides a cue for the self-righting reflex on the direction of "up/down". Apparently even blind cats can self-right based on their vestibular system.

moron4hire 5y ago

Any fall is a weightless environment, whether it's in a plane or off a building. But in a plane, you don't have the air rushing past your whiskers.

jstanley 5y ago

The cat might use visual cues to right itself. It might have been interesting to re-run the test with a more obvious "horizon" and see if the cats react to that. Then if the cat still doesn't right itself, it seems like it is using acceleration rather than vision to determine which way is down.

nealabq 5y ago
Do we know it's visual? If you drop a cat in darkness (onto a pillow of course), will it right itself? What if you put it in an elevator that accelerated downwards at 1G so the cat fell to the ceiling? How does it know which way is down? Is it the horizon, or the bright sky, or does the cat remember the scene before it was dropped? Or is it the air rushing by?
cecilpl2 5y ago
> Then if the cat still doesn't right itself, it seems like it is using acceleration rather than vision to determine which way is down. This is not possible because objects (including cats) in freefall do not experience the sensation of acceleration.
- true_religion 5y ago
  Before a cat (or any object) experiences free fall, they experience acceleration so they know which way gravity is pulling them. Surely, a cat can remember what happened to it in the last few seconds and instinctually put its feet in that direction?
  - throwawayben 5y ago
    You don't feel any acceleration from gravity - it can only be determined from other senses like vision or the air flowing over your skin/fur
    - true_religion 5y ago
      What about inner ear sensations? Or the pressure of your organs pushing against one another?