5 ms·

Planes do ”flap their wings”, just not the ones protruding from the fuselage.

trhway 2y ago
I think you're mistaking rotating for flapping. Rotation is one of those fundamental things differentiating our technological civilization from Nature.
- eesmith 2y ago
  Bacterial flagellum rotate. See also https://en.wikipedia.org/wiki/Rotating_locomotion_in_living_systems#Free_rotation https://en.wikipedia.org/wiki/Rotating_locomotion_in_living_... .
- andsoitis 2y ago
  > Rotation is one of those fundamental things differentiating our technological civilization from Nature. Rotation is very common in nature. Planetary rotation, inner-core rotation, spinning galaxies, dung beetle rolling, Keratinocyte migration, Rotifers, spirals, rotational symmetry, etc. What isn’t common (but not non-existent) is using rotation for locomotion in biology.
  - meow_catrix 2y ago
    Many plants and trees spread rotating ”helicopter seeds”. Many vines roto-grow themselves around vertical supports. Day flowers rotate to follow the sun. Apples and oranges fall on the ground and can roll far and wide. Walnuts too. Partial rotation is still rotation, of course: see animal joints in walk, trot and gallop. And then there’s the belly-up pig drunk on brewery grain rolling down the hill. That mash packs a wallop!
    - andsoitis 2y ago
      Yes! Which is why the idea that “ Rotation is one of those fundamental things differentiating our technological civilization from Nature” is not all that useful a statement.
  - K0balt 2y ago
    Huge swaths of microbes use electrostatic rotary motors driving screw type propellers, so if not say it’s that uncommon.
- meow_catrix 2y ago
  Those rotating things still produce their thrust by pushing a wing-shaped structure through air, producing a high-pressure zone on one side, and a low-pressure zone on another. That is what I was getting at. It is the same principle.
  - trhway 2y ago
    No, it is different. A prop or fan blade is inmovably attached to the shaft and pushed through the air the same way like the plane's wing, and the blade isn't flapped like the bird's wing.

I think you're mistaking rotating for flapping. Rotation is one of those fundamental things differentiating our technological civilization from Nature.

eesmith 2y ago
Bacterial flagellum rotate. See also https://en.wikipedia.org/wiki/Rotating_locomotion_in_living_systems#Free_rotation https://en.wikipedia.org/wiki/Rotating_locomotion_in_living_... .
andsoitis 2y ago
> Rotation is one of those fundamental things differentiating our technological civilization from Nature. Rotation is very common in nature. Planetary rotation, inner-core rotation, spinning galaxies, dung beetle rolling, Keratinocyte migration, Rotifers, spirals, rotational symmetry, etc. What isn’t common (but not non-existent) is using rotation for locomotion in biology.
- meow_catrix 2y ago
  Many plants and trees spread rotating ”helicopter seeds”. Many vines roto-grow themselves around vertical supports. Day flowers rotate to follow the sun. Apples and oranges fall on the ground and can roll far and wide. Walnuts too. Partial rotation is still rotation, of course: see animal joints in walk, trot and gallop. And then there’s the belly-up pig drunk on brewery grain rolling down the hill. That mash packs a wallop!
  - andsoitis 2y ago
    Yes! Which is why the idea that “ Rotation is one of those fundamental things differentiating our technological civilization from Nature” is not all that useful a statement.
- K0balt 2y ago
  Huge swaths of microbes use electrostatic rotary motors driving screw type propellers, so if not say it’s that uncommon.
meow_catrix 2y ago
Those rotating things still produce their thrust by pushing a wing-shaped structure through air, producing a high-pressure zone on one side, and a low-pressure zone on another. That is what I was getting at. It is the same principle.
- trhway 2y ago
  No, it is different. A prop or fan blade is inmovably attached to the shaft and pushed through the air the same way like the plane's wing, and the blade isn't flapped like the bird's wing.