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First Mechanical Gear Found in a Living Creature

popularmechanics.com

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Re: First Mechanical Gear Found in a Living Creature

#71

Post by dragonwriter »

niels_olson wrote: post #56
jonnathanson wrote: post #28

Earlier quoted context omitted.

There's never been a dichotomy between organic and mechanical. All things that move are mechanical. 'Mechanical' simply refers to motion. 'Organic' is a similarly blurry categorization. The terms you're looking for are 'natural' and 'artificial,' as in "of nature" and "of artifice (created by man)." These are natural gears, which are so surprising because we'd long assumed the gear itself to be an artificial concept.…

> All things that move are mechanical. How is that blurry? > 'Organic' is a similarly blurry category I thought "organic" was restricted to carbon chemistry. Seems pretty specific to me. > The terms you're looking for are 'natural' and 'artificial,' It may be that his choice of words conflicts with his meaning, or at least conflicts with your interpretation of his meaning, but doesn't make his original word choices l…

> I thought "organic" was restricted to carbon chemistry.

"Organic" has an older and still more widely encountered use, roughly, "relating to or derived from living organisms".

"organic" as pertaining to carbon chemistry is chemistry jargon that derived from the general use because of carbon's key role in biology.

Re: First Mechanical Gear Found in a Living Creature

#72

Post by mkmk »

ihsw wrote: post #61

This article was posted to reddit, and incidentally the author is a redditor. http://www.reddit.com/r/science/comments/1m9eke/scientists_d... They're taking questions.

Just to clarify, it looks like the journalist is taking questions, not the author of the paper.

Re: First Mechanical Gear Found in a Living Creature

#73

Post by crusso »

boldfield wrote: post #59
crusso wrote: post #41

Earlier quoted context omitted.

6. Creatures like this shake my faith in evolution. Why? It's easy to imagine a couple of touching pieces in the ancestor of the issid that aided in synchronizing the jumping mechanics. Over time, mutations in those touching pieces interlocked more firmly until they resembled what we think of as gears. There was pressure on those mutations to proceed toward gears since the gear mechanism is a potentially successful o…

It's easy to imagine a couple of touching pieces in the ancestor of the issid that aided in synchronizing the jumping mechanics. Over time, mutations in those touching pieces interlocked more firmly until they resembled what we think of as gears. If this were the case, would you not expect to observe these evolutionary steps in other organisms today? As noted in the article: ...there are many jumping insects like the…

If this were the case, would you not expect to observe these evolutionary steps in other organisms today?

Why? Just because one life form developed a feature doesn't mean that other life forms will have it.

As the article mentioned, there are other solutions to the same problem that other insects evolved. Probably the gears solution is statistically less likely.

Then again, if this was just discovered, how hard have we really been looking?

Re: First Mechanical Gear Found in a Living Creature

#74

Post by pygy_ »

dekhn wrote: post #57
pygy_ wrote: post #40

Earlier quoted context omitted.

No, it converts the proton concentration gradient into mechanical energy. The ATP synthase also works that way. The ADP and Pi are mechanically squeezed against each other in order to create the covalent bound. See the last two videos of [0] for the general process. The first three focus on details. [0] http://www.mrc-mbu.cam.ac.uk/category/slideshows/atpmovies

"ADP and Pi are mechanically squeezed against each other in order to create the covalent bond." I have a PhD in Biophysics. If I ever said "ADP and Pi were squeezed together", I'd have been laughed out of journal club. The fine details of the reaction coordinate are still being argued about. I'll grant you there are no canonical gears as a mechanical engineer would recognize them. I wasn't talking about the motive co…

Doctor of medicine here, with basic notions of chemistry and biochemistry from courses I took 16 years ago. I sure know what I'm talking about!

;-)

More seriously, I had inferred the squeezing from the videos I linked to.

If I understand properly, the mechanical constrains on the ADP, Pi and AA residuals involved result in the formation of the high energy covalent bound between the two phosphates.

Thus mechanical -> chemical energy.

I thought that the pressure between the electron clouds of the two molecules caused some superficial electrons to hop, resulting in the new covalent bound (that's what I meant by squeezing), and the dehydration.

Is this mostly correct (with possible intermediate steps where either the Pi or the ADP end up in a temporary covalent bound of even higher energy with subunits of the ÀTP synthase), or is this pure hogwash?

Also, thanks for the explanations regarding the flagellum, that's very interesting :-)

> I'll grant you there are no canonical gears as a mechanical engineer would recognize them. I wasn't talking about the motive coupling. But a number of the physical structures (proteins) that couple the anchoring to the moving body have gear like properties. These are used to orient and clock the moving body in its cycle.

Is it mediated by alternating, matching stripes of charged or polar AA residuals?

Re: First Mechanical Gear Found in a Living Creature

#75

Post by boldfield »

vdaniuk wrote: post #66
boldfield wrote: post #59

Earlier quoted context omitted.

It's easy to imagine a couple of touching pieces in the ancestor of the issid that aided in synchronizing the jumping mechanics. Over time, mutations in those touching pieces interlocked more firmly until they resembled what we think of as gears. If this were the case, would you not expect to observe these evolutionary steps in other organisms today? As noted in the article: ...there are many jumping insects like the…

Statistically, it is very likely that at any given point in time there will be only one species with the trait that humans consider significant.

I'm about to commit an HN faux pax here, but, citation? Off the top of my head I can think of traits which do not fit your assertion: vision in the 390-700nm wavelengths, hair/fur, eye placement (think predator v. prey), etc, etc.

Re: First Mechanical Gear Found in a Living Creature

#77

Post by swamp40 »

It is for beauty like this that I believe all living things were originally designed by some intelligence, somewhere.

Perhaps designed to mutate and evolve, or perhaps that was a limitation in the source materials, but there are some beautifully engineered living systems on our planet.

Re: First Mechanical Gear Found in a Living Creature

#78

Post by npsimons »

john_b wrote: post #11
alan_cx wrote: post #9

I wonder how its prevents wear? Could be something quite revolutionary there for the finding. Some sort of new organic lubricant, or something in the gears that self lubricates.

Maybe it doesn't. The last paragraph of the article implies that wear eventually would compromise the gears, but that the insect molting and replacing the old gears with new ones (frequently?) prevents it from being a problem.

Which leads to the classic answer to the age old question of how you make a car last forever: buy three, one to keep, and the other two for parts.

Re: First Mechanical Gear Found in a Living Creature

#79

Post by jlgreco »

sliverstorm wrote: post #25
bitwize wrote: post #15

Earlier quoted context omitted.

5) Organic creatures have mechanical systems as part of their physiology. "Mechanical" doesn't mean "made of metal", it means "uses movement and friction to achieve some effect". Some mechanical devices, such as levers and swivels, are seen frequently in the animal kingdom; others, such as gears, pulleys, and wheels, are almost never seen in nature. Discovering one of this latter category is a fascinating find.

Pulleys are not that rare. Block and tackle is, but you have pulleys in your hands.

Wikipedia defines pulleys as "A pulley is a wheel on an axle that is designed to support movement of a cable or belt along its circumference", though I think the wheel/axle requirement is probably shouldn't be considered a hard requirement.

On the other hand, I don't think I would call the loops that fishing line passes through along the length of a fishing pole "pulleys".

I guess I'd say that block and tackle is not common, and neither are "wheeled pulleys", but "friction pulleys" are.

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