One of the core arguments for Intelligent Design is Behe's Irreducible Complexity. For those who are not familiar with it, IC is a system in which if any part is taken out, the system falls apart. This means, according to Behe, that it could not have evolved by chance because the odds of each part evolving and then fitting together with the next is close to nothing.
However, Behe is not completely correct. Many of his examples of IC are Irreducibly complex in the sense that it could not evolve in the way he explains. However, there are several alternative explanations. After searching through them, the most convincing one I found, surprisingly, was written long before the term "Irreducible Complexity" existed.
In 1939, H.J. Muller, who later won the nobel prize in 1946, wrote a very interesting article about gene duplication and systems called "Reversibility in Evolution Considered from the Standpoint of Genetics". Homeotic complexes that start as a independant parts can, over time, grow dependant on each other. His work has been built upon countless times.
For instance, take the blood clotting system (which Behe no longer claims is IC). While the name "Ken Miller" may receive a groan from several ID proponents, realize that Behe actually retracted blood clotting as an example of IC because of articles such as his.
Miller's article follows Muller in the sense that the blood clotting cascade was created via mutation of a duplicated gene.
A good analogy for indepedant parts becoming depedant is to look at the evolution of the eurkaryotic cell. The Golgi apparatus packages proteins and sends them out. The Endoplasmic reticulum serves as a pathway for protein synthesis, and so on. If you took out any of the various parts of protein synthesis and transportation, the system falls apart. So, like the flagella, this must be Irreducibly Complex, right?
Actually, the ER, Golgi apparatus, and many other parts of the cell are made of chemicals very similiar to the membrane of the cell. The current theory is that infolding of the cell allowed for compartmentalization of functions (enzyme pathways) and thus more effective reactions. Another way to increase effectiveness is to have each component have a specific job. Over time, these compartments eventually became dependant on each other because no one component could do every job. Today, the parts seem so different that it is hard to imagine how it could arise naturally.
So the next time you yell "mouse-trap", think of Muller.
This message has been edited by wnope, 05-18-2005 09:27 PM
™ Version 4.2