Irreducible complexity

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==Examples of flawed arguments==
 
==Examples of flawed arguments==
Frequently, believers in this philosophy [[cite]] the eye as an example of something too complex to have evolved.  The argument is frequently presented with a question of the type, "What use is half an eye?". However if the question is recast as "What use is 50% of your present vision?", then it becomes clear that the question is badly formed, especially when keeping in mind that many species manage to survive with significantly less advanced eyes. Examples include the polychaete worms, which can distinguish between light and dark;<ref>Buchsbaum, R. ''Animals Without Backbones'' (Penguin 1958); vol.1, plate 64</ref> the simple eye-cup of the flatworms, for finding the direction of a light source; jellyfish and scallops, with simple eyes for detecting movement; [http://www.sciencenews.org/articles/20050514/fob2.asp][http://www.augsburg.edu/biology/photoofmonth/scallop-eyes.html], the famous compound eyes of the insects, which can make out simple shapes, and ultimately the complex eyes of the molluscs and vertebrates.
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Frequently, believers in this philosophy [[cite]] the eye as an example of something too complex to have evolved.  The argument is frequently presented with a question of the type, "What use is half an eye?". However if the question is recast as "Given a choice would you prefer to be completely blind or have 50% of your present vision", then it becomes clear that the question is badly formed, especially when keeping in mind that many species manage to survive with significantly less advanced eyes. Examples include the polychaete worms, which can distinguish between light and dark;<ref>Buchsbaum, R. ''Animals Without Backbones'' (Penguin 1958); vol.1, plate 64</ref> the simple eye-cup of the flatworms, for finding the direction of a light source; jellyfish and scallops, with simple eyes for detecting movement; [http://www.sciencenews.org/articles/20050514/fob2.asp][http://www.augsburg.edu/biology/photoofmonth/scallop-eyes.html], the famous compound eyes of the insects, which can make out simple shapes, and ultimately the complex eyes of the molluscs and vertebrates.
  
 
Another famed and also flawed example is "the watch on the beach."
 
Another famed and also flawed example is "the watch on the beach."

Revision as of 16:44, 25 August 2008

Pseudoscience Alert
This topic is a pseudoscience, and is not accepted by the scientific community as a valid discipline.
Although it may use scientific terminology, it does not use scientific methodology.
Remember: just because it sounds right doesn't mean it's actually right.

According to Creationwiki, "Irreducible complexity is a concept popularized by Lehigh University biochemist Michael Behe in his 1996 book Darwin's Black Box, which supports what is known as intelligent design theory. If something is irreducibly complex, then it can not be reduced to less complex functions, and therefore, could not develop by assembling preexisting components. Intelligent design theorists argue that while some systems and organs can be explained by evolution, those that are irreducibly complex cannot, but instead an intelligent designer must be responsible."[1]

Irreducible complexity stems from the claim that some biological systems appear to be too complex to have arisen by natural selection. It is one of the main arguments of the Intelligent Design movement. It is unscientific in the sense that it uses an ever shrinking amount of "gaps" (phenomena not yet explained by science) for support, and that it includes non-falsifiable assumptions, which are clearly violations of the Scientific method.

Contents

Humor

In a blog post about the Lenski affair, biologist Björn Brembs came up with a a hilarious alternative definition:

"I think I have now finally understood what "irreducibly complex" really means: a statement, fact or event so simple it cannot be simplified any further, but still too complex to be grasped by a creationist."

Explanation from uncyclopedia

An argument that states that because something doesn't work when broken down to its component parts it must be impossible for it to have been developed gradually.

Statistical examination of chance

Elementary statistics prove that dismissing chance as a whole is mathematically erroneous.

Imagine a situation where every base pair (DNA building blocks that make up genes and chromosomes) has an equal chance of mutating within a certain period of time. We can now plot these base pairs along the x-axis, the distance of the base pair to the x=0 is inversely proportional to its necessity (that is, base pairs that would harm the organism if they were to mutated will be closer to x=0 than base pairs that could mutate without harming the adverse effects.)

A typical exponential probability curve.

We assume that advantageous mutations are rare, meaning the gene density will drop with the distance from x=0, this can be plotted as a probability curve, every non-linear graph (a graph that's not a straight line), can be described by a power of a constant, the simplest form being f(x) = x2. In statistics, a continuous probability curve the, f(x), is related to x through an exponential function. Now, since exp[z] = e2, where e is Euler's Number[2] with a value of 2.71, it can easily be shown that the probability will never become zero (c0 = 1.)

In addition, one of the most important factors in evolution - the fundamental role of Natural selection, cannot be neglected. As a result of natural selection evolution is nothing like the blind random process that its critics sometimes claim it to be.

Examples of flawed arguments

Frequently, believers in this philosophy cite the eye as an example of something too complex to have evolved. The argument is frequently presented with a question of the type, "What use is half an eye?". However if the question is recast as "Given a choice would you prefer to be completely blind or have 50% of your present vision", then it becomes clear that the question is badly formed, especially when keeping in mind that many species manage to survive with significantly less advanced eyes. Examples include the polychaete worms, which can distinguish between light and dark;[3] the simple eye-cup of the flatworms, for finding the direction of a light source; jellyfish and scallops, with simple eyes for detecting movement; [1][2], the famous compound eyes of the insects, which can make out simple shapes, and ultimately the complex eyes of the molluscs and vertebrates.

Another famed and also flawed example is "the watch on the beach." It goes as follows: "if you find a watch on the beach, do you assume it got there by chance, or do you assume it was made by an intelligent designer?" The example is flawed because watches and their parts do not reproduce or mutate.

The above arguments are appeals to the common sense of the "Average Joe." Popular support is, however, not part of the scientific method; this can be easily understood when considering that a significant part of the world's population believes in astrology.

How "Irreducibly complex" structures form

One way in which "Irreducibly complex" structures could develop is via a process known as scaffolding, wherein a structure gains in complexity via duplication and mutation of parts, then parts are knocked out via mutations, leaving a structure with no direct linear development from the original, basic structure. Other paths by which irreducibly complex structures may form include cooption of parts from other structures. Both of these can be seen in the case of the bacterial flagellum, which includes many parts taken from a secretory pump.

See also

External links

References

  1. http://creationwiki.org/Irreducible_complexity
  2. http://en.wikipedia.org/wiki/E_(mathematical_constant)
  3. Buchsbaum, R. Animals Without Backbones (Penguin 1958); vol.1, plate 64
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