Evolution's new wrinkle: Proteins with cruise control provide new perspective

I am already foreseeing a whole new category of crappy creation/ID arguments.PZ Myers has something to say: Edited by rbp, : No reason given.Edited by rbp, : No reason given.Edited by Admin, : Make URL's in quote headings into active links.

Thread moved here from the Proposed New Topics forum.

But evolution doesn't have a control. So the biological organisms are rejecting evolution.Soon we'll have the stones jumping up and down saying, " Evolution
doesn't work".

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There no doubt exist natural laws, but once this fine reason of ours was corrupted, it corrupted everything. [blz paskal]

It sounds more like a feedback mechanism.And as usual, no deities need be involved.

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Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

actually, the article actually describes it as a positive control mechanism.Anyone else find it fantastically ironic that the guiding hand that ID claims is behind evolution... might be evolution?*edit* actually, article is pretty vague and paper isn't up on princeton site yet.Edited by AlienInvader, : caveats

G'day Coyote. Are you saying Coyote, then, that it's only the failed organisms that evolve?

I see, so now evolution is a guiding hand. That's new.

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There no doubt exist natural laws, but once this fine reason of ours was corrupted, it corrupted everything. [blz paskal]

You'll have to explain how you reached that conclusion.

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Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

http://link.aps.org/abstract/PRL/v100/e258103link to abstract with further link to actual paper... umm... but needs a subscription...i'm on a uni machine so yeah.from what i gather and from what someone else said on another site, authors don't claim or delve into any mechanistic aspects of directed evolution, they are simply trying to make an argument that in a very specific and localized case around the redox ability of group of proteins it's more accurate to model behavior with an optimal control model as opposed to a normal control model?... no idea what the difference is... anyway, it appears to be journalist that over-reaches.Edited by AlienInvader, : added view on thing

Organisms don't evolve. It's populations of organisms that evolve. And they do so when the environment changes such that a large number of individuals in that population do fail (to leave a descendent lineage). So, yes, in a sense evolution is caused by the failure of organisms (and adaptive genetic migration of those that succeed).

Right, so it's the populations of organisms that fail in their ability to fix harmful mutations that evolve. And so given 4 billion years of this type of behavior, why do they persist, against the natural laws?

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There no doubt exist natural laws, but once this fine reason of ours was corrupted, it corrupted everything. blz paskal

If the theory of evolution, particularly Darwinian evolution, is the valid explanation of species diversity, then we would expect that a control mechanism (that controls the rate of evolution) would evolve at some time. If a population is in an environment to which it is well adapted, then it is beneficial that the mutation rate be kept low (an 'if it aint broke, don't fix it' situation). If the environment changes or the population migrates such that the population is not well fitted to the new environment to the extent that it is in danger of extinction, then it would be beneficial for the mutation rate to increase to improve the chances that some offspring will be better suited to the new environment, and sufficiently so to continue the survival of that species (a 'let's re-invent the species' situation).Such a feedback control mechanism need not be in any way "directed", intelligent, or purposeful. In fact, just such a mechanism is found in almost all animals and includes the Heat Shock Proteins (HSP). These proteins, and the genes that encode them, are expressed, as the name implies, when the organism is subject to extreme environments such as temperatures, drought, acidity levels to which it is not well suited. Such proteins can act as mutagens increasing the mutation rate, or as agents to down-regulate expression of other proteins that act to repair genes that have been mutated by other, natural processes.This process can be modeled as a feedback mechanism that switches between negative feedback and positive feedback where environmental factors provide the switch. It's just like putting a foam cover over a microphone to keep it from squealing due to positive feedback with the speakers. The existence of this mutagenic control mechanism, exactly as predicted by Darwinian evolution, is to me one of the strongest arguments for the validity of that theory.

What? You just told us that it is directed by nature, which has to make the intelligent decision for the purpose of maintaining the species.

Nonsense. Trial and error, coupled with selection pressure, works just fine.No deities needed, as usual.Here is a good example, presented in an online video: Making Genetic Networks Operate Robustly: Unintelligent Non-design Suffices, by professor Garrett Odell.

Description: Mathematical computer models of two ancient and famous genetic networks act early in embryos of many different species to determine the body plan. Models revealed these networks to be astonishingly robust, despite their 'unintelligent design.' This examines the use of mathematical models to shed light on how biological, pattern-forming gene networks operate and how thoughtless, haphazard, non-design produces networks whose robustness seems inspired, begging the question what else unintelligent non-design might be capable of.

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Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

Mutations that are harmful in one environment may be beneficial in another - a long tail and curved claws may be great for tree climbing but useless, or even disadvantageous after a forest fire removes the trees; the onset of an ice-age will change what fur coloration is best for camouflage; industrial soot darkening trees will affect what wing coloration is most advantageous for a moth needing to hide from predatory birds. So, it's the sub-populations the fail in their ability to 'fix' beneficial mutations that survive and continue the evolutionary path in a new direction.