stevestory
Posts: 13407
Joined: Oct. 2005
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Salvador Cordova--you know him, the person a small minority of people thought might actually be dumber than AFDave--has a new post up at UD. Apparently he, too, is some kind of pilot, on top of having an engineering degree.
| Quote | June 14, 2006
Airplane magnetos, contingency designs, and reasons ID will prevail
Intelligent design will open doors to scientific exploration which Darwinism is too blind to perceive. The ID perspective allows us to find designed architectures within biology which are almost invisible to natural selection. Thus, the ID perspective is a far better framework for scientific investigation than the Darwinian perspective. What do I mean, and how will I justify my claim?
Let me illustrate my point with some anecdotes. I was piloting a small airplane in the spring of 2002. My airplane suffered a potentially serious systems failure during the flight. In piston powered aircraft, the electrical ignition system (called a magneto system) is life-critical. Aircraft engineers consider the magneto system so crucial that they design each engine with two redundant, independent magnetos. If one magneto fails, the other seamlessly takes over. In fact, these dually redundant systems are so effective that a pilot will not even know if one of the magnetos failed in mid-flight until he’s back on the ground doing a routine inspection of his airplane!
Well that’s what happened to me on my flight in 2002. My left magneto gave out and I continued flying using only the right magneto. There are no instruments on board to indicate if one of the magnetos fail. The failure is usually discovered after landing. The airplane flies just fine without on one magneto as long as the other magneto is working. That is by design.
How did I eventually realize I had a left magneto failure? After I landed, I took a break, then prepared to take off again. I went through a routine procedure to check out the airplane’s airworthiness.
I started the engine and followed several procedures on my check list. I then got to the part on the checklist where I separately test the integrity of each magneto. I shut off one magneto and leave the other on.
“Engine 1800 RPM: check!”
“Right magneto: check!”
“Left magneto: Whoa! Holy smokes!”
The engine practically cut off during the left magneto check. There are no instruments to indicate a mid-flight magneto failure. Such system failures are detected after landing. Thus, I had previously been flying through the air blissfully unaware of the left magneto failure. “Ignorance is bliss”. Ha! As I came to the realization that I had been flying on only one magneto, I had visions of what might have happened had the right magneto also failed, visions of me having to fly the airplane with a dead engine, and visions of me gliding the airplane to a safe landing in someone’s backyard…(ah, but I digress)….
What does this have to do with biology and Darwinism? One way Darwinists conclude something is evolutionary junk, a vestigial feature, or an otherwise useless biological artifact is to apply “knock-out” experiments on an organism. If a piece of the organism is knocked out, and the organism still functions well and is otherwise “fit”, then the knocked-out piece is deemed useless, an evolutionary leftover, junk, or even bad design.
What’s wrong with such logic you ask? Well allow me to clarify. Imagine if one applies this line of reasoning to the architecture of a magneto-fired airplane engine:
| Quote | | We knocked out the left magneto system on Airplane X and determined the airplane flies just as well without it. We knocked out the right magneto system on Airplane Y and determined the airplane flies just as well without it. We conclude therefore from these knockout experiments that neither the left magneto nor the right magneto have any functional significance since the airplanes were clearly fit without them. Magnetos are therefore unneeded vestigial artifacts, junk, and evidence poor design, totally useless to the airplane. Furthermore this is further evidence that airplanes are made by blind watchmakers. |
Think I’m kidding, and evolutionary biologists don’t make these kinds of obviously bad inferences?
See:
Minimal genome should be twice the size, study shows
| Quote | “Previous attempts to work out the minimal genome have relied on deleting individual genes in order to infer which genes are essential for maintaining life,” said Professor Laurence Hurst from the Department of Biology and Biochemistry at the University of Bath.
“This knock out approach misses the fact that there are alternative genetic routes, or pathways, to the production of the same cellular product.
When you knock out one gene, the genome can compensate by using an alternative gene.
But when you repeat the knock out experiment by deleting the alternative, the genome can revert to the original gene instead.
Using the knock-out approach you could infer that both genes are expendable from the genome because there appears to be no deleterious effect in both experiments.” |
Knockout experiments have also been used to argue “junk DNA” is junk. This is out rightly bad science, but it persists because of Darwinist’s eagerness to close their eyes to design and paint various artifacts in biology a the product of a clumsy blind watchmaker rather than an intelligent designer.
The strategy of using several different means to achieve a particular goal where each of the individual means is sufficient by itself to achieve the goal is used in many engineered systems to ensure that the goal will be achieved, even if one or more of the means fail. For example, the space shuttle’s on-board inertial guidance system, consists of five redundant computers!
How does this relate to biology and intelligent design? Let me quote geneticist Michael Denton in his book Nature’s Destiny:
| Quote | It now appears that a considerable number of genes, perhaps even the majority in higher organisms, are completely or at least partially redundant. One of the major pieces of evidence that this it the case has come from so-called gene knockout experiments, where a gene is effectively disabled in some way using genetic-engineering techniques so that it cannot play its normal role in the organism’s biology. A classic example of this came when a gene coding for a large complex protein known as Tenascin-C, which occurs in the extra cellular matrix of all vertebrates, was knocked out in mice, without any obvious effect. As the author of a paper commenting on this surprising result cautions: “It would be premature to conclude that [the protein] has no important function …[as] it is conserved in every vertebrate species, which argues strongly for a fundamental role.” The protein product of the Zeste gene in the fruit fly drosophila, which is a component of certain multi-protein complexes involved in transcribing regions of the DNA, can also be knocked out without any obvious effect on the very processes in which it is known to function.
The phenomenon of redundant genes is so widespread that it is already acknowledge to pose something of an evolutionary conundrum. Although in the words of the author of one recent article, “true genetic redundancy ought to be, in an evolutionary sense, impossible or at least unlikely,” partially redundant genes are common. As another authority comments in recent review article: “Arguments over whether there can be true redundancy are moot for the experimentalist. The question is how the functions for partially redundant genes can be discovered given that partial redundancy is the rule.
And it seems increasingly that it is not only individual genes that are redundant, but rather that the phenomenon may be all-pervasive in the development of higher organisms, existing at every level from individual genes to the most complex developmental processes. For example, individual nerve axons, like guided missiles or migrating birds, are guided to their targets by a number of different and individually redundant mechanisms and clues. The development of the female sexual organ, the vulva, in the nematode provides perhaps the most dramatic example to date of redundancy exploited as a fail-safe device at the very highest level. A detailed description of the mechanism of formation of the nematode vulva is beyond the scope of this chapter, suffice it to say that the organ is generated by means of two quite different developmental mechanism, either of which is sufficient by itself to generate a perfect vulva.
It seems increasingly likely that redundancy will prove to be universally exploited in many key aspects of the development of higher organisms, for precisely the same reason it is utilized in many other areas–as a fail safe mechanism to ensure that developmental goals are achieved with what amounts to a virtually zero error rate.
Now, this phenomenon poses an additional challenge to the idea that organisms can be radically transformed as a result of a succession of small independent changes, as Darwinian theory supposes. For it means that if an advantageous change is to occur, in an organ system such as the nematode vulva, which is specified in two completely different ways, then this will of necessity require simultaneous changes in both blueprints. In other words, the greater the degree of redundancy, the greater the need for simultaneous mutation to effect evolutionary change and the more difficult it is to believe that evolutionary change could have been engineered without intelligent direction.
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Denton describes what I call contingency designs. It should be hopefully obvious that contingency designs are exactly the kinds of designs that are hard pressed to be created via natural selection. How does one evolve a contingency design when the primary design functions just as well? If a creature mutates a failure into a life-critical primary system, it will more likely be selectively eliminated before it can evolve a fully functioning backup system!
ID’s explanatory filter is therefore a potentially more effective tool at identifying designs which elude Darwinian style tests (such as knockout experiments) for functionality. ID’s explanatory filter looks for possible functionality by identifying specified complexity in biological artifacts which may not evidence any immediate effect on the organism if the biological artifact is knocked out.
I will pursue this more perhaps in another post, but I point out, IBM may have unwittingly detected designs which would otherwise elude the fitness test. See:
Invasion of the IBM engineers[link]
The ability of the Explanatory Filter to identify designs in biology which Darwinists would sooner perceive as an accident and which will elude “fitness tests” is another reason I believe ID will prevail as the proper scientific framework for investigating biology.
The Explanatory Filter may very well succeed in identifying places to look for design which may have otherwise been easily overlooked. I will post on this more, but in the meantime in case you’ve missed it, here is my essay on a related topic: How IDers can win the war[link]
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Filed under: Intelligent Design — scordova @ 10:44 am |
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