Monday, November 21, 2005

Butterfly `invents' advanced light-emitting device (LED)

Excerpts of articles, all on the one topic, the amazing (that word occurs a lot in the articles) discovery that a group of butterflies, the swallowtails, has "evolved" [sic] an advanced type of light-emitting device (LED)!

How butterfly wings use living colour, The Independent, 20 November 2005, Steve Connor ... The brilliant colours of a butterfly's wing are generated in the same way as the high-definition pictures of the trendiest plasma-screen TVs, scientists have found. [This is just the latest example of what Macbeth called the "Not Enough Mindlessness" and "too much perfection" failure of the two main logical corollaries of Darwinian evolution:

"MY basic definition of classical Darwinism in Chapter 1 included two corollaries stemming straight from Darwin himself. First, in the evolution of any structure of function, every intermediate stage must be of advantage to the species. [Darwin C., "The Origin of Species," [1859], Harvard University Press, First edition, 1966, reprint, pp.199-201] Second, natural selection tends only to make each organic being as perfect as, or slightly more perfect than, the other inhabitants of the same country with which it has to struggle for existence. [Ibid., p.201] These were described as logical corollaries because they are derived from thinking about the implications of the theory, rather than from observation of nature. They are really predictions. ... First Corollary-Not Enough Mindlessness Why must every intermediate step be advantageous to the species? Because Darwin conceived natural selection as a mindless process, as the impersonal operation of purely natural forces. If it is mindless, it cannot plan ahead; it cannot make sacrifices now to attain a distant goal, because it has no goals and no mind with which to conceive goals. Therefore every change must be justified by its own immediate advantages, not as leading to some desirable end. ... Second Corollary-Too Much Perfection. Darwin formulated this himself in the first edition of The Origin of Species: `Natural selection tends only to make each being as perfect as, or slightly more perfect than, the other inhabitants of the same area.' [Ibid., p.201]" (Macbeth N., "Darwin Retried: An Appeal to Reason," Gambit: Boston MA, 1971, pp.97,99-100, 102. Emphasis original).
How would a "mindless process" (such as the natural selection of random mutations) produce the machinery to generate colours "in the same way as the high-definition pictures of the trendiest plasma-screen"? And why would it do it, when it only needs to make it "as perfect as, or slightly more perfect than, the other inhabitants of the same area"?] For the past 30 million years, African swallowtail butterflies have used the principles of light-emitting devices to generate the vivid colours of their wings, says Peter Vukusic, a physicist at Exeter University. A new study shows butterflies' wings are coated with an ultra-thin layer of molecules that form microscopic air spaces where fluorescent pigments absorb ultraviolet light and re-emit it as vivid patches of blue and green. The air spaces themselves have complex, multi-layered mirrors at the bottom to force light out through the top surface of the wings. Further analysis, published in the journal Science, has found that the airspaces are arranged in such a precisely uniform manner that the fluorescent light is prevented from leaking out sideways, to make sure the colours are even brighter and clearer. [Again, how and why would a `blind watchmaker' go to all this trouble to give colour to butterfly wings? OTOH, an Intelligent Designer would do it to send us a biotic message, that: 1) all life was made by a single Designer; and 2) the Designer did not make life fully naturalistically:
"Why would a designer create life to look like evolution? What possible m could a designer have to be misleading? Is the designer trying to trick us? This is now the evolutionists' standard argument. This book responds by showing they do not truly know their own theory. Life was designed to look unlike evolution, and to see this, one must understand evolutionary theory deeply. ... message theory ... claims that life was intentionally designed to communicate a message. .... Life was made by no ordinary designer, but by one with unusual intentions. Identifying these intentions resolves the difficulties. Features of life that seemed inexplicable become understandable once the designer's goal is recognized. That goal was consistently pursued by the designer. Throughout nature it guided design choices and shaped the pattern of life. The data admit to no other solution. The pattern is intricate, yet so consistent it could not result from thoughtlessness. The pattern was premeditated. It was designed intentionally to meet a single-minded goal. The designer's goal was a reasonable one, carried out in a reasonable way and with meticulous care. Ironically, evolution is central to that goal. Life was designed to thwart evolutionary explanation. ... The biotic message is the sum of the unifying and non-naturalistic messages. The Unifying Message: `This system of living objects was constructed by a single source (e.g., a common designer).' ... The Non- naturalistic Message: `This system of living objects did not result from a naturalistic (evolutionary) process.'" (ReMine W.J., "The Biotic Message: Evolution Versus Message Theory," St. Paul Science: Saint Paul MN, 1993, pp.17-18, 22. Emphasis original).]
Dr Vukusic said that the butterfly had essentially invented a biological version of the light-emitting diode (LED) millions of years before they were developed by electrical engineers. "It's amazing that butterflies have evolved such sophisticated design features which can so exquisitely manipulate light and colour. Nature's design and engineering is truly inspirational," Dr Vukusic said. [Note the language of intelligent design, for a system which is supposed to have been cobbled together by a `blind watchmaker': "the butterfly had essentially invented a biological version of the light-emitting diode" and "such sophisticated design features which can so exquisitely manipulate light and colour. Indeed, nature's design and engineering is truly inspirational"!] The wings of African swallowtails are coated in micro-scales - regular air-pockets within the stiff material that makes up the insect's external skeleton. "The function of the micro-scales is identical to those in the LED; they prevent the fluorescent colour from being trapped inside the structure and from being emitted sideways," Dr Vukusic said. [Not just "similar to ... the LED" but "identical to ... the LED"!] "The scales on the wing also have a specialised mirror underneath, again very similar in design to that in the LED. [Again "very similar in design"!] This mirror upwardly reflects all the fluorescent light that gets emitted down towards it." The result is a very efficient system for the fluorescent emission of light that gives the butterfly significant control of the direction in which the light is emitted, Dr Vukusic said. "The fact that nature and technology have converged on this pretty analogous device is amazing," he said. ... [The reason why Vukusic calls it "amazing" is because intuitively he feels that this "technology" of nature was just that: technology - "the practical application of knowledge" not the mindless tinkering of a `blind watchmaker'! I have added a quote of this first article excerpt to my "Problems of Evolution" book outline, PE 13.3.1 "Insects ... Butterfly's wing colours".]

Butterflies Beat Humans to Photonic Crystals, Discovery News , Larry O'Hanlon, Discovery News Nov. 18, 2005- African swallowtail butterflies have been found using what was thought to be exclusively human advanced technology: high-efficiency photonic crystals like those of light-emitting diodes, or LEDs. [In fact it is "advanced technology ... high-efficiency photonic crystals like those of light-emitting diodes"!] A microscopic study of the wing scales of the butterflies has uncovered arrays of two-dimensional, light-controlling "photonic" crystals and fluorescent pigments. These not only allow the reflection of very particular shades of blue and blue-green, but they actually absorb some other colors and change them into the same blues and blue-greens. That accounts for how the small group of African butterflies, and others found elsewhere in the world, can give off such strikingly brighter-than-bright color. "It's just amazing," said optics researcher Pete Vukusic of Exeter University in the UK. [If it is only "a small group of ... butterflies" that have this "advanced technology", this would indicate it has no great advantage over the less "advanced technology" of other butterflies, especially if this small group have had this "advanced technology" for "the past 30 million years"! But it may be that some other butterflies will be found to have this system. Either way, it seems clearly to be an unnecessary "tour de force by a virtuoso ... exercising his own fantasy rather than adapting himself to mundane conditions in a utilitarian way (note that Macbeth cites this same "swallowtail butterfly" but for another reason):

"Third, many animals behave in incredibly complicated and mysterious ways. The life course of the swallowtail butterfly is a familiar example (though few laymen know the remarkable details such as the total dissolution and reconstitution of the organs and even of the cells), but other insects are equally striking. These are marvels, beyond any doubt; but there is no compelling reason to regard them as adaptations. Each is a tour de force by a virtuoso, but the virtuoso seems to be exercising his own fantasy rather than adapting himself to mundane conditions in a utilitarian way. The books are full of examples of this virtuoso work, which is especially common among insects." (Macbeth N., "Darwin Retried: An Appeal to Reason," Gambit: Boston MA, 1971, p.70)
and so would be consistent with this being a deliberate `biotic message' sent to us from life's Designer, that life's origins was not fully naturalistic:
"Message theory would not be especially enlightening, however, if its sole statement were the unity of nature. Nature's unity has been known for millennia. Message theory embraces this unity, but its real challenge is to go further, and the needed insight is the non-naturalistic message. Life was designed to look unlike the result of natural processes-it was designed to look unlike evolution. ... Yet evolutionary theory is the centerpiece of message theory. Evolutionary theory is itself data - data of pivotal importance. ... Life was designed to resist all naturalistic interpretations, not just Darwin's." (ReMine W.J., "The Biotic Message: Evolution Versus Message Theory," St. Paul Science: Saint Paul MN, 1993, pp.24-25. Emphasis original).]
"We got to it one way and nature got to it another way." Only nature did it 30 million years earlier, he added. Vukusic and his colleague Ian Hopper have a short paper on the discovery in the Nov. 18 issue of Science. In the case of manufactured LEDs, it's electricity that makes the light, which is then controlled by photonic crystals. In butterflies, sunlight makes the colored light by being used in two ways: first by pigments that reflect only the desired color; second by fluorescent pigments absorbing other wavelengths of light to power up emission of the same preferred color. What makes LEDs and butterfly wings so strikingly similar is that both use photonic crystals to control where the light goes. Artificial photonic crystals are usually made in neat arrays, using silica. Butterflies grow photonic crystals like hair or fingernails, said Vukusic. Once grown, they are no longer living tissue and they continue to work long after a butterfly is dead and pinned in a sample case. As for why swallowtails need to be so extraordinarily flashy - the function seems to be for territorial signaling to other butterflies of the same species, said Vukusic. [The "function [of] ... territorial signaling to other butterflies of the same species" is clearly a case of `a sledgehammer to crack a nut'. unction" ] Other researchers have found that the butterflies have receptors in their eyes for the same colors they flash. [So the `blind watchmaker' would not only have had to have made the LED's, he would also have had to make the "receptors in their eyes for the same colors they flash"!] So by reflecting, fluorescing and aiming that color with photonic crystals, butterflies are just sending light signals as loudly and clearly as they can. "It's showing us what a biological system can do," said Helen Ghiradella of State University of New York at Albany. Ghiradella has studied how fireflies make use of color which are of exactly the same wavelength they see best. "(These butterflies) show a control of light that is absolutely unbelievable," said Ghiradella.... [Agreed that it "is absolutely unbelievable" that a `blind watchmaker' would have, and could have, made this "advanced technology". So why believe it? Here's why:
"So now the Emperor walked under his high canopy in the midst of the procession, through the streets of his capital; and all the people standing by, and those at the windows, cried out, `Oh! How beautiful are our Emperor's new clothes! What a magnificent train there is to the mantle; and how gracefully the scarf hangs!' in short, no one would allow that he could not see these much- admired clothes; because, in doing so, he would have declared himself either a simpleton or unfit for his office. Certainly, none of the Emperor's various suits, had ever made so great an impression, as these invisible ones. `But the Emperor has nothing at all on!' said a little child. `Listen to the voice of innocence!' exclaimed his father; and what the child had said was whispered from one to another. `But he has nothing at all on!' at last cried out all the people. The Emperor was vexed, for he knew that the people were right; but he thought the procession must go on now! And the lords of the bedchamber took greater pains than ever, to appear holding up a train, although, in reality, there was no train to hold." (Hans Christian Andersen, "The Emperor's New Clothes," Andersen's Fairy Tales, 1837).]

Butterfly wings work like LEDs, BBC, 18 November 2005 ... When scientists developed an efficient device for emitting light, they hadn't realised butterflies have been using the same method for 30 million years. Fluorescent patches on the wings of African swallowtail butterflies work in a very similar way to high emission light emitting diodes (LEDs). These high emission LEDs are an efficient variation on the diodes used in electronic equipment and displays. The University of Exeter, UK, research appears in the journal Science. In 2001, Alexei Erchak and colleagues at the Massachusetts Institute of Technology (MIT) demonstrated a method for building a more efficient LED. Most light emitted from standard LEDs cannot escape, resulting in what scientists call a low extraction efficiency of light. ... The LED developed at MIT used a two-dimensional (2D) photonic crystal - a triangular lattice of holes etched into the LED's upper cladding layer - to enhance the extraction of light. ... The butterflies use the fluorescent patches to signal each other And layered structures called Bragg reflectors were used to control the emission direction. These high emission devices potentially offer a huge step up in performance over standard types. Pete Vukusic and Ian Hooper at Exeter have now shown that swallowtail butterflies evolved an identical method for signalling to each other in the wild. [There's that "identical method" again! Note what it was: "a two-dimensional (2D) photonic crystal ... to enhance the extraction of light. ... layered structures called Bragg reflectors ... to control the emission direction. ... a huge step up in performance over standard types"!] Swallowtails belonging to the Princeps nireus species live in eastern and central Africa. They have dark wings with bright blue or blue-green patches. The wing scales on these swallowtails act as 2D photonic crystals, infused with pigment and structured in such a way that they produce intense fluorescence. Pigment on the butterflies' wings absorbs ultra-violet light which is then re-emitted, using fluorescence, as brilliant blue-green light. ... Most of this light would be lost were it not for the pigment being located in a region of the wing which has evenly spaced micro-holes through it. ... This slab of hollow air cylinders in the wing scales is essentially mother nature's version of a 2D photonic crystal. [It seems that "mother nature" is the scientific naturalists' version of the Intelligent Designer?] Like its counterpart in a high emission LED, it prevents the fluorescent colour from being trapped inside the structure and from being emitted sideways. The scales also have a type of mirror underneath them to upwardly reflect all the fluorescent light that gets emitted down towards it. Again, this is very similar to the Bragg reflectors in high emission LEDs. "Unlike the diodes, the butterfly's system clearly doesn't have semiconductor in it and it doesn't produce its own radiative energy," Dr Vukusic [said] "That makes it doubly efficient in a way. "But the way light is extracted from the butterfly's system is more than an analogy - it's all but identical in design to the LED." [Note that again: "more than an analogy - it's all but identical in design to the LED"! One of the defenses against Paley's `watch implies a watchmaker' argument is that "a very weak analogy argument". But as Behe points out, the closer that life's machinery gets to humanly designed machinery, the stronger Paley-type arguments are:

"A modern philosopher, Elliott Sober of the University of Wisconsin in his book Philosophy of Biology, explains Hume's reasoning for us in more detail: `Hume believes...we must ask how similar watches and organisms really are. A moment's reflection shows that they are very dissimilar. Watches are made of glass and metal; they do not breathe, excrete, metabolize, or reproduce.... The immediate consequence, of course, is that the design argument is a very weak analogy argument. It is preposterous to infer that organisms have a given property simply because watches happen to have it.' [Sober E., "Philosophy of Biology," Westview Press: Boulder CO, 1993, p.34]. But Sober does not agree with Hume: `Although Hume's criticism is devastating if the design argument is an argument from analogy, I see no reason why the design argument must be construed in this way. Paley's argument about organisms stands on its own, regardless of whether watches and organisms happen to be similar The point of talking about watches is to help the reader see that the argument about organisms is compelling.' [Ibid., pp.34-35] In other words, David Hume thought that the design argument depended on a close similarity in accidental details of biological organisms to other designed objects. But this line of thinking would destroy all analogies, since any two nonidentical objects will differ in more ways than they are similar. For example, by Hume's thinking you could not liken a car to an airplane, even though both are transportation devices, because an airplane has wings and a car does not, and so forth. Sober rejects Hume's thinking because he says the intelligent design argument is really something called an inference to the best explanation. This simply means that, given a choice between the competing explanations of intelligent design versus unguided natural forces, Paley's argument would seem more likely (at least, says Sober, before Darwin came along). Sober's conclusion is fine as far as it goes, but he could also have noted that the argument from analogy is still valid; it was just twisted out of shape by Hume. Analogies always are set up so that they either explicitly or (more frequently) implicitly propose that A is like B in a restricted subset of properties. Rust is like tooth decay in that they both start from small spots and work outward, even though tooth decay takes place in living materials, is caused by bacteria, can be inhibited by fluoride, and so on. A Rube Goldberg machine is like the blood-clotting system in that they are both irreducibly complex, even though they have many differences. In order to reach a conclusion based on an analogy, it is only necessary that the deduction flow out of the shared properties: The irreducibly complex Rube Goldberg machine required an intelligent designer to produce it; therefore the irreducibly complex blood-clotting system required a designer also. Incidentally, even by Hume's criteria, the analogy between a watch and a living organism could be made very strong. Modern biochemistry probably could make a watch, or a time-keeping device, out of biological materials-if not now, then certainly in the near future. Many biochemical systems keep time, including the cells that pace the heart, the system that initiates puberty, and the proteins that tell the cell when to divide. Moreover, biochemical components are known that can act as gears and flexible chains, and feedback mechanisms (which are necessary to regulate a watch) are common in biochemistry. Hume's criticism of the design argument that asserts a fundamental difference between mechanical systems and living systems is out of date, destroyed by the advance of science which has discovered the machinery of life. Sober continues his analysis of Hume: `I now tum to Hume's second criticism of the design argument, which is no more successful than the first...[Hume] contends that if we are to have good reason to think that the organisms in our world are the products of intelligent design, then we must have looked at lots of other worlds and observed intelligent designers producing organisms there. [Ibid., p.35] Hume is criticizing design as an inductive argument. An example of an induction is the argument that because no pigs have ever been observed to fly, pigs in all probability cannot fly. A conclusion of design based on induction would require that we have experience of living things being designed. Hume thinks that since we have not observed such designing in our world, we must look to other worlds for such an experience. Since we have no knowledge of other worlds, however, then we have no experience to make an induction. Sober believes that Hume's argument is invalid because, again, Sober thinks that intelligent design is actually an inference to the best explanation, not an inductive argument. And again Sober is right as far as he goes, but he could have gone further. Although Hume's objection to the inductive argument might have been valid in his day, it has been destroyed by the advance of science. Modern biochemistry routinely designs biochemical systems, which are now known to be the basis of life. Therefore we do have experience in observing the intelligent design of components of life. There have probably been tens of thousands of experiments in which new biochemical systems were put together, and in the future there will be many, many more." (Behe M.J., "Darwin's Black Box: The Biochemical Challenge to Evolution," Free Press: New York NY, 1996, pp.217-219).]
Dr Vukusic agreed that studying natural designs such as this could help scientists improve upon manmade devices. "When you study these things and get a feel for the photonic architecture available, you really start to appreciate the elegance with which nature put some of these things together," he said. ... [If Vukusic said, "you really start to appreciate the elegance with which" the `blind watchmaker' "put ... these things together", the "emperor's new clothes" absurdity would be evident!]

The Secret of Bright Butterfly Wings: LED Technology, Livescience , Ker Than, LiveScience, 17 November 2005 ... Science was way behind nature in developing LED light technology, a new study finds. The beautifully colored wings of African swallowtail butterflies manipulate light using engineering tricks similar to those found in digital displays. [Again the language of intelligent design: "manipulate light using engineering tricks".] The butterflies have black wings with bright patches of green and blue, which they use to communicate across long distances. Microscopic scales covering the wings absorb ultraviolet light and then re-emit it. The re-emitted light interacts with fluorescent pigments found on the butterflies' wings to produce the vibrant green-blue color. ... Researchers investigating how the scales work found that they have many similarities to digital devices known as light emitting diodes, also known as LEDs, which are found in everything from computer and television screens to traffic lights. The first LEDs invented in the late 1960s weren't very bright. They produced a lot of light but most of it tended to either become trapped inside the device or to spread sideways and become diluted. In the early 1990s, engineers came up with ways to get around these problems. They outfitted LEDs with tiny mirrors that could reflect and channel the light and made microscopic holes in them to help the light escape. ... While studying the wings of swallowtail butterflies, researchers discovered that there were a lot of similarities between the scale coverings and LEDs. The scales that cover the butterflies' wings contain tiny structures called "photonic crystals," which act very much like the microholes found in LEDs. "[The scales] prevent the fluorescent light from being trapped inside the scales and from being emitted sideways," said Pete Vukusic of Exeter University, a researcher in the study. The scales on the wing also have a specialized mirror underneath them, which act very much like the tiny mirrors found in LEDs. [Note: "a specialized mirror underneath them"] The mirror reflects all the scattered fluorescent light it receives upward, giving the butterflies control over the direction in which in the light is emitted. The study was reported in the Nov. 18 issue of the journal Science.... [Here is an apt, even prophetic (1985), quote by Michael Denton:

"But it is not just the complexity of living systems which is so profoundly challenging, there is also the incredible ingenuity that is so often manifest in their design. Ingenuity in biological design is particularly striking when it is manifest in solutions to problems analogous to those met in our own technology. Without the existence of the camera and the telescope, much of the ingenuity in the design of the eye would not have been perceived. Although the anatomical components of the eye were well known by scientists in the fifteenth century, the ingenuity of its design was not appreciated until the seventeenth century when the basic optics of image formation were first clearly expressed by Kepler and later by Descartes. However, it was only in the eighteenth and nineteenth centuries, as the construction of optical instruments became more complicated, utilizing a movable iris, a focusing device, and corrections for spherical and chromatic aberration, all features which have their analogue in the eye, that the ingenuity of the optical system could at last be appreciated fully by Darwin and his contemporaries. We now know the eye to be a far more sophisticated instrument than it appeared a hundred years ago. Electro-physiological studies have recently revealed very intricate connections among the nerve cells of the retina, which enable the eye to carry out many types of preliminary data processing of visual information before transmitting it in binary form to the brain. The cleverness of these mechanisms has again been underlined by their close analogy to the sorts of image intensification and clarification processes carried out today by computers, such as those used by NASA, on images transmitted from space. Today it would be more accurate to think of a television camera if we are looking for an analogy to the eye. There are dozens of examples where advances in technology have emphasized the ingenuity of biological design. ... But it is at a molecular level where the analogy between the mechanical and biological worlds is so striking, and the genius of biological design and the perfection of the goals achieved are most pronounced." (Denton M.J., "Evolution: A Theory in Crisis," Burnett: London, 1985, pp.332-333).]

Glowing Butterflies Shine With Natural LEDs, National Geographic News, John Roach, November 17, 2005 For 30 million years African swallowtail butterflies have dazzled their mates with glowing splashes of color on their wings (see photo). And the process they use to control the flow of light in their wings is strikingly similar to a technology that humans only recently developed, physicists report. [Again this "strikingly similar to a technology that humans ... developed" is evidence that the analogy of design is strong. Here is another quote on that by Michael Behe:

"The 18th-century clergyman William Paley likened living things to a watch, arguing that the workings of both point to intelligent design. Modern Darwinists disagree with Paley that the perceived design is real, but they do agree that life overwhelms us with the appearance of design. ... The resemblance of parts of life to engineered mechanisms like a watch is enormously stronger than what Reverend Paley imagined. In the past 50 years modern science has shown that the cell, the very foundation of life, is run by machines made of molecules. There are little molecular trucks in the cell to ferry supplies, little outboard motors to push a cell through liquid. In 1998 an issue of the journal Cell was devoted to molecular machines, with articles like `The Cell as a Collection of Protein Machines' and `Mechanical Devices of the Spliceosome: Motors, Clocks, Springs and Things.' Referring to his student days in the 1960's, Bruce Alberts, president of the National Academy of Sciences, wrote that `the chemistry that makes life possible is much more elaborate and sophisticated than anything we students had ever considered.' In fact, Dr. Alberts remarked, the entire cell can be viewed as a factory with an elaborate network of interlocking assembly lines, each of which is composed of a set of large protein machines. He emphasized that the term machine was not some fuzzy analogy; it was meant literally. ...The strong appearance of design allows a disarmingly simple argument: if it looks, walks and quacks like a duck, then, absent compelling evidence to the contrary, we have warrant to conclude it's a duck. Design should not be overlooked simply because it's so obvious." (Behe M.J., "Design for Living," The New York Times, February 7, 2005).]
From the lasers used to read information on CDs and DVDs to the data carried across oceans along optical fibers, the control of light is essential to modern living. One way scientists control light is through the use of light emitting diodes (LEDs). These electronic devices are made out of semiconductor material-a type of solid substance that can conduct electricity- that lights up when a current passes through them. LEDs are found in traffic lights, computer screens, car brake lights, and many other gadgets that flash color without the use of a conventional light bulb. But physicists had long deemed traditional LEDs inefficient, because most of the light they created was unable to escape the semiconductor material. All the generated light rays that went sideways or downward, for example, were essentially lost. Improved LEDs After years of research, physicists recently overcame these limitations with "high-efficient LEDs." The new breed of LEDs uses specialized mirrors and tiny structures called photonic crystals to generate more usable light from the semiconductor materials. Pete Vukusic and Ian Hooper, physicists at the University of Exeter in the U.K., report that nature perfected this method in the African swallowtail butterfly long ago. The butterfly has natural versions of these specialized mirrors and photonic crystals, which brighten the fluorescent blue and green splotches on their wings. "The analogy is to the way light is extracted from both systems, which is really exciting, it is amazing," Vukusic said. He and Hooper report the discovery in tomorrow's issue of the journal Science. Alexei Erchak is the founder of Luminus Devices in Woburn, Massachusetts. While a graduate student at the Massachusetts Institute of Technology in Cambridge, he developed the first prototype high-efficient LED in 2001. Erchak said he is "amazed" at the similarity between the structure in the butterfly wing and his own LEDs. "We must have been doing something right," he said. "Knowing that nature can confirm the inventions we came up with certainly gives a good feeling." [There's that word "amazed" (again). Also note (again) that "Erchak [who] ... developed the first prototype high-efficient LED" does not say, "We must have been doing something right ... Knowing that" a mindless, purposeless process "can confirm the inventions we came up with." Because then it may be seen that the Darwinian Emperor has no clothes!] Mirrors and Crystals High-efficient LEDs reflect and direct light outward, including light that would be lost with traditional LEDs. The first trick is the use of specialized mirrors called distributed Bragg reflectors (DBRs), which are multilayered mirrors that bounce back light of a specific wavelength or color. This multilayer mirror is placed underneath the LED, meaning that any light of the desired wavelength directed downward is reflected upward. The second trick is the use of photonic crystals, which prevent light of the desired wavelength from going sideways or getting "trapped." The result is better control over the flow of light and thus a more efficient LED, Vukusic said. ... Wondering how the swallowtail butterfly controls the flow of light, study authors Vukusic and Hooper examined a wing under powerful microscopes. They found that each wing contains hundreds of thousands of tiny scales. Each scale has a slab on it where fluorescent pigment is stored. Fluorescence is the process by which high-energy ultraviolet radiation is absorbed and reemitted as a lower-energy visible radiation. In the case of the butterflies, sunlight is reemitted as blue or green light. Underneath the pigment slab are layers of reflective surfaces-natural versions of DBR mirrors. The butterfly's "mirrors" are tuned to reflect blue-green light. Like the photonic crystals in high-efficient LEDs, the pigment slabs are structured so that blue-green light does not radiate sideways from the slab. As in high-efficient LEDs, the light is directed up and out. The combined effect of the reflectors and the structure of the slab, explained Vukusic, is a much brighter blue-green fluorescence than could be achieved with pigment alone. The brighter wings allow the butterflies to better signal to each other, he added. "Nature has had to come up with very elegant and ingenious design protocols in order to achieve a significant control over the flow of light," Vukusic said. "Those are design protocols which may point the way to newer, better, more efficient systems." Erchak, the high-efficient-LED pioneer, quipped that the finding "means that butterflies are smarter than MIT students."... [Again, if instead of "nature" Vukusic said, "a `blind watchmaker' ... has had to come up with very elegant and ingenious design protocols in order to achieve a significant control over the flow of light," the absurdity would be evident. ]

Butterfly Wings Share Light Tricks with TV Science, Scientific American, November 18, 2005, David Biello ... The wings of a butterfly are a thing of beauty as they shimmer and dance in the breeze.They are also a marvel of light-directing properties. [Another word "marvel" that indicates an intuitive recognition of design.] Researchers have discovered that the swallowtail butterfly of eastern and central Africa, Papilio nireus, has fluorescent wings that reflect and direct light in much the same way that the modern light- emitting diodes in high-end computer screens and televisions do. Pete Vukusic and Ian Hooper of Exeter University in England studied the colored parts of the swallowtail's wings and found that the scales that comprised them contain photonic crystals whose atoms are spaced so precisely that only certain wavelengths of light can pass through. The crystals are also saturated with fluorescent pigments that help them create specific wavelengths of light, visible to us as bright colors. Tiny, mirrorlike structures known as distributed Bragg reflectors reflect this fluorescent light as well as all the other light the photonic crystal allows to pass through. The result: butterfly wings that transform ordinary sunlight into brilliant greens and blues incredibly efficiently. Thus what the butterflies evolved to do, scientists have built light-emitting diodes to do, employing the exact same components--photonic crystals and Bragg reflectors--in search of ever better ways to project and direct light. The findings are published in the current issue of Science. ... [Note the use of that thought-stopper "evolved". If the journalist Biello was more specific and wrote, "evolved by the natural selection of random mutations" then maybe he, or at least some of his readers, might be skeptical about that.]

30 million years ahead - how the butterfly beat technology to it,, November 19, 2005 ... Butterflies have evolved a unique mechanism to create a dazzling display of colour which puts physicists in the shade. ... [If this really is "unique" to a small group of butterflies, then that will be that much harder for the Darwinists to explain.] Modern light emitting devices have traditionally been inefficient because most of the light created can't escape, but now in a paper published in Science, University of Exeter scientists have discovered the butterfly has been doing what physics couldn't, for more than 30 million years. ... In order for LEDs (light emitting diodes) to function efficiently physicists have spent years analysing their design to come up with features which help to maximise the amount of light released. These include a specialised mirror to reflect light and micro holes which stop light from being trapped inside the device or from spreading sideways. But it seems anything we can do nature can do better. When Dr Pete Vukusic studied African Swallowtail butterflies he found the creatures had evolved to include exactly these adaptations. [This may be another example of irreducible complexity, i.e. all the components of the system have to be in place for it to work. ] This butterfly emits blue-green light, which it uses for signalling, using a fluorescent pigment on its wings. Dr Pete Vukusic, of the School of Physics said: "It's amazing that butterflies have evolved such sophisticated design features which can so exquisitely manipulate light and colour. [Again the same intuitive recognition that "such sophisticated design features" could not plausibly be put together by unintelligent natural processes.] Nature's design and engineering is truly inspirational. [See previous comment] Pigment on the butterflies' wings absorbs ultra-violet light which is then re-emitted, using fluorescence, as brilliant blue-green light. This adds to the colour intensity of the wing. Much of this light would be lost, resulting in a much duller effect, but the pigment is located in a region of the wing which has evenly spaced micro-holes through it." [If this LED system started as a non-LED precursor system with "a much duller effect" and it did not work (e.g. "for territorial signaling to other butterflies of the same species"), then natural selection would have eliminated it. OTOH, if the non-LED system did work, then why would it need to be improved (especially if other butterflies with the non-LED system are doing just fine with it (especially if it is only a small group that has had this "sophisticated design"for "more than 30 million years"!] He continues: "The function of the micro- scales is identical to those in the LED; they prevent the fluorescent colour from being trapped inside the structure and from being emitted sideways. The scales on the wing also have a specialised mirror underneath them, again very similar in design to that in the LED. This mirror upwardly reflects all the fluorescent light that gets emitted down towards it. The result is a very efficient system for fluorescent emission that gives the butterfly significant control of the direction in which the light is emitted." Source: University of Exeter ... [See previous comments on "identical".]

PS: See tagline quote being my next installment of Paley's design argument.

Stephen E. Jones, BSc (Biol).
"Problems of Evolution"

"Nor, thirdly, would it bring any uncertainty into the argument, if there were a few parts of the watch concerning which we could not discover, or had not yet discovered, in what manner they conduced to the general effect; or even some parts, concerning which we could not ascertain, whether they conduced to that effect in any manner whatever. For, as to the first branch of the case; if, by the loss, or disorder, or decay of the parts in question, the movement of the watch were found in fact to be stopped, or disturbed, or retarded, no doubt would remain in our minds as to the utility or intention of these parts, although we should be unable to investigate the manner according to which, or the connection by which, the ultimate effect depended upon their action or assistance: and the more complex is the machine, the more likely is this obscurity to arise. Then, as to the second thing supposed, namely, that there were parts, which might be spared without prejudice to the movement of the watch, and that we had proved this by experiment, -these superfluous parts, even if we were completely assured that they were such, would not vacate the reasoning which we had instituted concerning other parts. The indication of contrivance remained, with respect to them, nearly as it was before" (Paley W., "Natural Theology: or, Evidences of the Existence and Attributes of the Deity, Collected from the Appearances of Nature," [1802], St. Thomas Press: Houston, TX, 1972, reprint, p.4)

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