ElShamah - Reason & Science: Defending ID and the Christian Worldview
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ElShamah - Reason & Science: Defending ID and the Christian Worldview

Otangelo Grasso: This is my personal virtual library, where i collect information, which leads in my view to the Christian faith, creationism, and Intelligent Design as the best explanation of the origin of the physical Universe, life, biodiversity


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The peacock

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1The peacock Empty The peacock Mon Jun 30, 2014 7:09 am

Otangelo


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The Beauty of the Peacock Tail and the Problems with the Theory of Sexual Selection

http://reasonandscience.heavenforum.org/t1799-the-peacock#2949

The tail of the peacock
1. Darwin once remarked the tail of the peacock made him sick because the unnecessary extravagance of nature was suggestive of Intelligent Design. What made Darwin sick then still holds true today, he never solved the problem, and it is more in evidence by the problem of Irreducible Complexity (IC).
2. The peacock tail contains spectacular beauty because of the large feathers, bright, iridescent colours and intricate patterns. The colours in the tail feathers are produced by an optical effect called thin-film interference. The eye pattern has a high degree of brightness and precision because the colour-producing mechanisms contain an extremely high level of optimum design. According to the theory of sexual selection, the peacock tail has gradually evolved because the peahen selects beautiful males for mating. However, there is no satisfactory explanation of how the sexual selection cycle can start or why the peahen should prefer beautiful features. In addition, there is irreducible complexity in both the physical structure of the feather and in the beautiful patterns.
3. When a peacock displays his tail feathers during courtship, a magnificent ‘fan formation’ of feathers forms a beautiful backdrop to the body of the peacock. An adult peacock has an average of 200 tail feathers and these are shed and re-grown annually. Of the 200 or so feathers, about 170 are ‘eye’ feathers and 30 are ‘T’ feathers. The ‘eyes’ are sometimes referred to as ocellations (an eyelike spot or marking).
4. It is difficult to determine how many genes would be required to specify the aesthetic features of a peacock tail feather because it is not known how the tail feather grows. However, a conservative estimate can be made by assuming that each separate aesthetic feature is specified by one gene. By assuming that each colour and each shape within the eye pattern represents a separate feature, and taking into account the other features of the feather, the total number of aesthetic features in a single feather comes to about 20…In particular, it may be that many genes are required to produce each shape in the eye pattern since the eye pattern is formed from the coordinated arrangement of over 100 barbs. In addition, the fanning-out of barbs in the top of the feather, where there is no stem, is a complex feature that may well need several controlling genes.
Even if only 20 genes are required to specify the beautiful features of the peacock tail, this still amounts to a lot of genetic information. A gene typically consists of 1,000 chemical units of information (base pairs). Therefore, 20 genes would contain many thousands of chemical units of information. According to evolutionists, all of this information has appeared gradually by genetic mistakes and by sexual selection.
4. The problem is that goals are achieved via the simplest means, but via extravagant and irreducibly complex means with great depth of integration.
5. New discoveries might prove that an IC system could be reduced a bit but it is not possible to reduce it too much because the system would stop to be functional. Thus any simplest functional system is an IC system.
6. IC systems prove an intelligent designer who must be a person.
7. That person all men call God.
8. God exists.

https://answersingenesis.org/natural-selection/peacock-tail-beauty-and-problems-theory-of-sexual-selection/

Evolutionists fully recognize that sexual selection would often produce features that reduce the ability to escape from predators because aesthetic features often make a creature more conspicuous and slower. However, if females prefer beautiful males for mating, then the advantage of beauty can outweigh the advantages of camouflage and maneuverability. According to the theory of sexual selection, ornamental features will develop to the point at which the disadvantages of being caught by a predator outweigh the advantages of being selected by a female.14

Evolutionists recognize that a female such as a peahen does not have aesthetic appreciation and that the preference of the female is based on an instinctive response. In addition, it is recognized that the instinctive response needs to be specified by one or more genes in the genetic code15 called preference genes.


Do the peacock tail feathers play a role in the courtship ritual?

There is no doubt that the peacock tail feathers do play a role in the courtship ritual of peafowl. Many creatures have a courtship ritual that acts as a cue for mating. In the case of the peafowl, the peacock shows his intention to the peahen by displaying his feathers. However, even though the display feathers have a role in the courtship ritual, this does not necessarily mean that the female is ‘attracted’ to the feathers. When the peahen observes the feathers of the peacock, it may be that her only reaction is to understand that the peacock is ready for mating.

Some questions.....

(i) Why should the female select a ‘beautiful’ feature?
(ii) How can the sexual selection cycle start by chance?
(iii) How can multiple aesthetic features start by chance?
(iv) How can the female appreciate subtle features?
(v) Some features contain irreducible mechanisms


(i) Why should the female select a ‘beautiful’ feature?

When females have a preference, that preference becomes self-perpetuating.18 However, there is no reason a fashion should always be a ‘beautiful’ fashion. According to evolution, preference genes appear by totally random processes and therefore there could be a fashion for all kinds of features including ugly features. In reality, where males have decorative features, such as the birds of paradise and the peafowl, it is clear that every aesthetic feature contains a very high degree of aesthetic merit.

To overcome the problem that females always prefer beautiful features, evolutionists have proposed the ‘good genes’ theory that proposes that beauty is directly related to health and fitness.19 However, the decorative features found in nature are so overwhelmingly beautiful that it would require an extremely strong correlation between beauty and health and there is no evidence for such a strong correlation.

(ii) How can the sexual selection cycle start by chance?

Another big problem with the theory of sexual selection is the question of how the sexual selection cycle can start by chance. The cycle cannot start until there is both a trait gene and a preference gene. Therefore for a sexual selection cycle to get started there must be the appearance of two new genes in the DNA. Since genes contain complex information and since the preference gene and trait gene are useless on their own, it must be concluded that sexual selection could never spontaneously commence on the basis of incremental changes to the DNA.

To overcome the problem of the simultaneous appearance of two new genes, evolutionists have proposed that the two genes appear at different places and different times in the following way.20 First, a female spontaneously produces a preference gene for a male with, say, a long tail. This gene lies dormant for perhaps many generations without any opportunity to be expressed. Then one day, a male spontaneously generates a gene which produces a longer tail. The female then selects that male and some of their offspring have both the trait gene and the preference gene. Therefore, the cycle is in place and ready to develop and perpetuate long tails.

At first, this scenario may seem plausible. However, it still relies on simultaneous chance events. Firstly, there must be a preference gene that matches a trait gene. Secondly, there must be a chance meeting between the right female and male. The first gene to arise also has to survive genetic drift until the male gene arises. Therefore, even with the scenario given by the evolutionists, it is clear that the sexual selection cycle is extremely unlikely to get started.

(iii) How can multiple aesthetic features start by chance?

The starting of one sexual selection cycle is difficult to explain by chance. However, when a creature contains many separate aesthetic features, the problem becomes even more pronounced because many cycles must be started. In the case of the peacock, there are many aesthetic features in the tail. In addition, the peacock also has several aesthetic features in the rest of its body. For example, it has a bright blue neck, patterns around the eyes, a crown on the head and speckled contour feathers. This array of features would probably require many sets of preference genes and trait genes.

(iv) How can the female appreciate subtle features?

It may well be possible that a peahen has a preference for obvious features such as a long tail. However, there are some extremely subtle features in the peacock which are not easy to recognize. These subtle features include an absence of a stem in the upper part of the eye pattern, the brown colouring of the stem near to the eye pattern and the intricate shape of the ‘T’ feathers. It may be reasonable to argue that a peahen could recognize whether a peacock had lost its eye feathers or T feathers. However, to discern subtle changes in these feathers would require tremendously detailed observation.

The above features are so subtle that many people do not notice them. In addition, it is necessary to get quite close to the feather to recognize such features. Since peahens do not undertake close visual inspections of the peacock, they would have to have a much better eye for detail than a human being in order to recognize the subtle features of the peacock tail.

Darwin himself recognized the problem of subtle aesthetic features. Darwin said, ‘Many will declare that it is utterly incredible that a female bird should be able to appreciate fine shading and exquisite patterns. It is undoubtedly a marvellous fact that she should possess this almost human degree of taste’.21 What is really incredible is that evolutionists really believe that a peahen is able to recognize fine shading and exquisite patterns. There is no evidence that the peahen can recognize such subtle aesthetic features.

(v) Some features contain irreducible mechanisms

Some of the structures that produce the aesthetic features in the peacock tail are irreducible. This means that they require several features to be simultaneously present in order for the structure to function. One example of an irreducible structure is the thin-film interference. Thin-film interference in a feather requires all of the following features to be simultaneously present:

1. Flat barbule(s)

2. Keratin layer(s)

3. Correct thickness of keratin layer(s)

Since evolution is supposed to work by changing one parameter at a time, thin-film interference cannot be produced by a process of evolution. For example, if there was a random gene mutation that suddenly caused a barbule to become flat, this change would not be enough to cause thin-film interference. Even if a barbule were to become flat and acquire a layer of keratin, this would still not produce a thin-film colour unless the keratin was the right thickness.

Getting the right thickness of keratin by chance is very difficult because the keratin thickness has to be within a very narrow range for thin-film interference to work. For thin-film interference to work, the thickness of keratin normally has to be within a range of 0.4–1.5 µ. However, keratin can be formed in thicknesses from 0.2 µ up to 1 mm. For example, nails and feather stems have keratin with a thickness of around 1 mm. If one considers 1,000 different layers of keratin which all have a different thickness ranging from 1 µ, 2 µ, 3 µ, etc., all the way to 1,000 µ (1 mm), only one or two out of the thousand thicknesses would produce thin-film interference. Therefore, it is inconceivable that a peacock could acquire a flat barbule and exactly the right thickness of keratin simultaneously. The only way to produce iridescent feathers is to make a fully functioning flat thin-film barbule from the beginning.

The fact that thin-film interference is a delicate and sophisticated mechanism is fully acknowledged by evolutionists. For example, Mason says the following:

‘The theory of thin films as the cause of iridescence, although it fits all the observed facts, cannot but inspire one to marvel at the perfection of nature’s method of producing these colours with such uniformity through successive generations, especially when a slight general variation in thickness of the films of the feathers of a bird, such as a peacock, would be enough to alter its coloration completely.’22
This is an important quote because Mason’s studies on the colour of peacock feathers are referred to by most modern texts on bird coloration. Notice how the author refers to the ‘perfection of nature’s method’, and marvels at how the thin-film is maintained in successive generations. If it is hard to understand how the peacock ‘maintains’ its delicate structures through successive generations then how does the evolutionist explain how it could have evolved in the first place?

(vi) Some features contain irreducible beauty

According to evolution, a complex pattern like the eye pattern in the peacock’s feather has evolved by the accumulation of hundreds of genetic mistakes occurring over vast periods of time. However, patterns like the blue ellipsoid in the eye are irreducible, i.e. they require several features to be simultaneously present in order for there to be a clear pattern. If only one barb in a peacock tail feather was to have a patch of blue colour this would not produce a beautiful pattern. Such a random change would arguably cause the peahen to deselect, not select the pattern. Since evolution requires every step change to have a selective advantage, the eye pattern cannot evolve but must be designed complete from the beginning.

Of course, the beauty of the peacock tail display is vastly beyond what is required to make a cue for the peahen.




http://harunyahya.com/en/Articles/4303/the-physical-basis-of-the

Chinese scientists have discovered a delicate mechanism of tiny hairs in peacock feathers filtering and reflecting different wavelengths of light. According to a study performed by Fudan University physicist Jian Zi and colleagues, published in the journal Proceedings of the National Academy of Sciences, the feathers' bright colors are produced not by pigments, but by tiny, two-dimensional crystal-like structures.

Zi and his colleagues used powerful electron microscopes to reveal the basis of the colors in the feathers. They examined the barbules of the male green peacock (Pavo rnuticus), in other words the even smaller micro hairs that come off of barbs emerging from the tavuskusu1central stem of the feather. Under the microscope, they encountered the lattice design in the black-and-white picture to the right. This consisted of rods made of melanin, a protein, bound together with keratin, another protein. The researchers observed that these two-dimensional structures, each with a width hundreds of times thinner than a human hair, were arranged one behind the other on the micro hairs. Using additional optical examinations and calculations, the scientists examined the spaces between the crystals and their effects. As a result, it was revealed that the dimensions and shapes of these spaces in the lattice led to light being reflected at slightly different angles and thus to a variation in color.

"The male peacock tail contains spectacular beauty because of the brilliant, iridescent, diversified, colorful eye patterns," said Zi, who continued, "when I watched the eye pattern against the sunshine, I was amazed by the stunning beauty of the feathers." (2) Zi stated that until their study, the exact physical mechanism producing the colors in peacock feathers had not been known, and that although the mechanisms they had revealed were simple, they were absolutely ingenious.

tavuskusu4Obviously, there is a very specially regulated design in peacock feather patterns. The tiny lattices and spaces between them are of the greatest importance in this design. The adjustment between the spaces is particularly striking. Were these not so arranged as to reflect light at slightly different angles to one another, then this variation in color would not take place.

The greater part of the color in the peacock feather is based upon structural coloration. There is no pigment in those parts of the feather that exhibit structural coloration, and colors reminiscent of those on the surface of a soap bubble are able to emerge. The color of human hair comes from pigment, and no matter how much care a person may take of his or her hair, it is never as shiny and beautiful as a peacock feather.

It has also been stated that this intelligent design in the peacock can be a source of inspiration in industrial design. Andrew Parker, a zoologist and coloration expert at the University of Oxford, who interpreted Zi's findings says that discovering so-called photonic crystals in peacock feathers could allow scientists to adapt the structures for industrial and commercial applications. These crystals could be used to channel light in telecommunications equipment, or to create new tiny computer chips. (3)

It is clear that the peacock has marvelous patterns and a special design, and that thanks to the imitation of this mechanism, maybe in the near future, we shall see objects and accessories covered in the brightest of coatings. Yet how did such a gorgeous, intelligent and inspirational design first emerge? Could the peacock know that the colors in its feathers depended on crystals and the spaces between them? Could the feather have itself brought the feathers on its body into being and later have decided to add a coloring mechanism to them?
Could it then have arranged that mechanism in such a way as to produce those stunning designs? Of course, not.

tavuskusu3For example, if we were to encounter marvelous patterns made out of colored stones as we walked beside the edge of a river, and if we also saw that there were eye-like designs arranged like a fan, then we would think that these had been laid out in a conscious manner, and not that they had appeared by chance. It would be evident that these patterns, reflecting an artistic perspective and addressing human aesthetic tastes, had been made by an artist. The same thing applies to peacock feathers. In the same way that pictures and designs reveal the existence of the artists who produced them, the patterns in the peacock feather reveal the existence of the Creator Who made them. There can be no doubt but that it is God Who brought together and arranged the crystal-like structures in the peacock feather and produced such marvelous patterns from them.

https://reasonandscience.catsboard.com

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