
Functioning 'mechanical gears' seen in nature for the first time (2013) - zachrose
http://phys.org/news/2013-09-functioning-mechanical-gears-nature.html
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randcraw
You wonder how this near ideal shape could evolve.

Maybe a pair of opposing plates preceded this to better sync the legs, and the
plates became wheels to allow longer hops. Then adding bumps to each wheel is
imaginable since it would sync a bit better.

But a long series of identical deep evenly spaced detents along one wheel and
a perfectly matched series of gear nubs on the opposing wheel is quite a bit
more complex and a phylogeny that's not at all intuitive, to me anyway.

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Vexs
Evolution can be nigh-impossible to understand sometimes, but this one seems
straightforward- as you mentioned, it was originally two discs, which gained
bumps- bugs that had better bumps were more likely to survive, and thus the
bumps probably became more defined and streamlined, forming ridges, and later
"gears"\- and if there's one thing the body likes to do, it's symmetry.

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dekhn
at the end of your last sentence, I'd generalize that to "if there's one thing
the universe likes, it's symmetry."

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conceit
> the legs always move within 30 'microseconds' of each other

> This is critical for the powerful jumps that are this insect's primary mode
> of transport

> even miniscule discrepancies in synchronisation between the velocities of
> its legs at the point of propulsion would result in "yaw rotation" \-
> causing the Issus to spin hopelessly out of control.

> "This precise synchronisation would be impossible to achieve through a
> nervous system, as neural impulses would take far too long for the
> extraordinarily tight coordination required,"

> Interestingly, the mechanistic gears are only found in the insect's juvenile
> – or 'nymph' – stages, and are lost in the final transition to adulthood

So, how do the adults or other grasshoppers synchronize their jumps if the
nervous system can't do it and cog-wheels aren't involved?

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chrisbennet
From September 12, 2013

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dang
Also discussed at
[https://news.ycombinator.com/item?id=8212984](https://news.ycombinator.com/item?id=8212984).

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danharaj
One must, absolutely must, wonder how many marvels of life we have destroyed
having never witnessed their splendor.

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nycthbris
But what about ATP synthase?

