161–170 of 191 posts
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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.
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Could you clarify/expound on this?
Evolution works by incremental changes, each of which to a first approximation must be at least neutral and preferably advantageous to producing offspring. In order for evolution to get from A to B, there must be a path of incremental advantageous changes to get from here to there. It can't magically leap from one optimum to another. So you see things like the way the same basic body plan is reused endlessly in the n…
In this representation of life it is directed and goal based. This is a misunderstanding of evolution that was common in a world that saw humanity as the peak of the process of evolution. For this reason Darwin perferred to think of it as a directionless bush rather than a directed tree.
1: http://en.wikipedia.org/wiki/File:Tree_of_life_by_Haeckel.jp...
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I think it depends on the direction of the acceleration. The John Stapp experiment was horizontal acceleration, right? Right above that: "... if g-forces are not quickly reduced, death can occur. Resistance to "negative" or "downward" g, which drives blood to the head, is much lower. This limit is typically in the −2 to −3 g (about −20 m/s² to −30 m/s²) range."
relevant: https://en.wikipedia.org/wiki/Euthanasia_Coaster
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.
God is real.
"They're rather specialized, and there are lots of other jumpers that don't have them, so there must be some kind of advantage." Not necessarily. Evolution has a lot to do with path dependence and in no way guarantees the best of all possible adaptations.
Almost every complex AND specialized adaptation has an advantage. In this case it seems pretty obvious that gears can be better than friction at transmitting torque.
I think a better phrasing would be, "the summation of all adaptations in addition to environmental state (including benefits or constraints to itself and all others) has led to the survival in its present environment".
It's really about optimization gradients in a particular time/environmental/social niche. Everything can change with the purturbation of any factor--but that's evolution for you. Adative curve fitting.
Earlier quoted context omitted.
Evolution works by incremental changes, each of which to a first approximation must be at least neutral and preferably advantageous to producing offspring. In order for evolution to get from A to B, there must be a path of incremental advantageous changes to get from here to there. It can't magically leap from one optimum to another. So you see things like the way the same basic body plan is reused endlessly in the n…
Whoa. That blew my mind. So we're evolving in such a way to be able to make combinatorial multi-gene changes- by evolving brains big enough to be able to develop gene engineering?
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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 ->…
Protein-interaction videos often make molecular reactions seem "deterministic" when in reality everything is quite stochastic; the molecules are "bouncing" around like crazy and each step may go back and forwards several times before completing. That said, I love the videos--its really amazing to think about all these little proteins bending and folding around all the time!
I knew that chemical bounds were vibrating (with a frequency proportional to their energy, E=h(nu)), but, for some reason, I had never envisioned macromolecules wiggling and vibrating as a whole.
Updating mental model :-)
Earlier quoted context omitted.
Almost every complex AND specialized adaptation has an advantage. In this case it seems pretty obvious that gears can be better than friction at transmitting torque.
I don't think you can really get away with saying that. I think a better phrasing would be, "the summation of all adaptations in addition to environmental state (including benefits or constraints to itself and all others) has led to the survival in its present environment". It's really about optimization gradients in a particular time/environmental/social niche. Everything can change with the purturbation of any fact…
