Wednesday, February 17, 2010

Junk Protein Not so Worthless After All

One problem with evolution is its strong bias toward viewing everything in biology as a kludge. When a newly discovered structure is examined, evolutionists take one look and conclude it is leftover junk. After all, blind, unguided mutations and other processes just happened to produce everything we see. The evolutionist’s going in position is that biology is a fluke. We’re lucky anything works.

As we have seen, this expectation pervades evolutionary thinking, and shows up again and again to be wrong. The once-we-thought-it-was-junk-but-now-we-see-how-it-works is a consistent theme in evolutionary thought. In recent years we've seen the so-called junk DNA turn up performing useful functions. More recently this story has repeated itself at the protein level. Designs that were once considered to be so much junk are now found to be essential. Evolution sure it helpful. Here is how one evolutionist described this latest rags-to-riches story:

Here we have a molecule that serves an important role in how cells function and survive, but it contains these puzzling 'junk' sequences that don't seem to have any apparent purpose. Our work suggests that this disorder is really a way of creating flexibility, allowing the protein to function as a molecular switch, a process that is thought to go wrong in certain diseases.

Evolution has provided researchers with convenient modular structures, areas that are repeated over and over again to make up proteins, and so we tend to dismiss the interspersed disordered sequences that don't seem to have any definable structure. Here we show that the weak molecular interactions in a disorganized protein equence are essential in giving this protein its unique attributes.

Well it is good to see that evolution has been helping researchers by providing convenient modular structures. At least evolution does something right.

5 comments:

  1. William Bialek - Professor Of Physics - Princeton University:
    Excerpt: "A central theme in my research is an appreciation for how well things “work” in biological systems. It is, after all, some notion of functional behavior that distinguishes life from inanimate matter, and it is a challenge to quantify this functionality in a language that parallels our characterization of other physical systems. Strikingly, when we do this (and there are not so many cases where it has been done!), the performance of biological systems often approaches some limits set by basic physical principles. While it is popular to view biological mechanisms as an historical record of evolutionary and developmental compromises, these observations on functional performance point toward a very different view of life as having selected a set of near optimal mechanisms for its most crucial tasks."
    http://www.princeton.edu/~wbialek/wbialek.html

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  2. Cornelius -

    "After all, blind, unguided mutations and other processes just happened to produce everything we see. The evolutionist’s going in position is that biology is a fluke. We’re lucky anything works."

    A total grotesque of a strawman argument. Especially from one who claims to understand how it works.

    Evolution through natural selection is not 'random chance'. It is a blind process, true, but that only means there is no forward planning. Mutations are not planned and animals cannot keep a non-beneficial mutation just because it will be useful to them in the future, for example.

    That is not to say the entire process is a fluke, and it is a woefully common Cretionist/ID fallacy to claim it is. Such faulty thinking leads people to claim the intimidating height of Mount Improbable is impossible to climb.

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  3. Cornelius Hunter: One problem with evolution is its strong bias toward viewing everything in biology as a kludge.

    A first-order approximation is that natural selection would limit the amount of "junk", but the process and rate of optimization depends on the relative costs involved.

    Cornelius Hunter: The once-we-thought-it-was-junk-but-now-we-see-how-it-works is a consistent theme in evolutionary thought.

    You're confusing theory with data. Whenever something new or interesting is discovered, you imply that it undermines the Theory of Evolution somehow or other. New and interesting things are discovered every day, but the scientists making these discoveries keep talking as if evolution was involved, oblivious to what is obvious to you.

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  4. I'm not sure how seriously anyone would ever consider the proposal that flexible regions are junk. The suggestion they are functional goes back to Pauling. Actually, it was the conservation of some of these regions in evolution that suggested biochemists better hunt for a function for them. The quoted scientist is saying intrinsically disordered or 'NORS' regions had no APPARENT function. 'Junk' in quotes. But he went looking for functionality and found it. A shocking rebuttal to evolution? No. I'm not sure how design hypothesis would do better, especially as we are not supposed to infer the intent of the designer. I have owned several cars that have designed parts with no function-weird fins, a faux-spoiler, little hood ornaments, mounting brackets that go with another model....

    Ref:
    Loopy Proteins Appear Conserved in Evolution
    Journal of Molecular Biology
    Volume 322, Issue 1, 6 September 2002, Pages 53-64

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  5. Robert:

    "I'm not sure how seriously anyone would ever consider the proposal that flexible regions are junk."

    Point well taken. The "junk" claims are often not universal amongst evolutionists, but sometimes they do seem to be. Each case is different. It is safe to say, however, that evolutionary theory has repeatedly led different evolutionists, at different times, studying different structures, to expect or conclude "junky-ness". It is an enduring theme, and for obvious reasons.

    Furthermore, this expectation rapidly becomes, if not is initially, metaphysical. For instance, the later finding of function and even efficiency, usually makes no difference because the design never was to our liking.


    "A shocking rebuttal to evolution? No."

    But of course that was not the point. Another evolutionary strawman.

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