Life Science Blog

Breaking down irreducible complexity

January 17, 2008

Darwin famously wrote in the Origin of Species “If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous successive slight modifications, my theory would absolutely break down.” Those who trumpet intelligent design, like the Discovery Institute in Seattle, have referred to this “irreducible complexity” as a way of disproving evolutionary theory. They say that complex biochemical systems like the eye could not have possibly evolved in a step-wise fashion as predicted by Darwinian theory. But recent research on hormone/receptor interaction and cellular signaling shows they might not be looking closely enough at complexity.

In the last few years there has been a small flurry of research chipping away at irreducible complexity. The research demonstrates how complex genetic and hormone/receptor interactions, much like that of lock and key, could have evolved without both elements present. It may be difficult to imagine the development of the lock without the key to open it and vice versa. Yet the new research suggests that these systems simply developed slowly in tandem, possibly with different functions, until pivotal mutations made the key fit the lock perfectly. Following such changes, the newly sophisticated systems were able to explode in functional applications.

Proponents of intelligent design are right to argue that evolutionary theory, as it currently stands, fails to explain the development of some exceedingly complex organs and molecular processes. Their error is to dally so eagerly in the face of such biological intricacy, insisting that Darwin has failed us. Could be he’s merely stumped us for the time being.


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1 Comment

Ted Herrlich says:

There has been more than a little science tearing down Irreducible Complexity. Every example in Michael Behe’s book “Darwin’s Black Box” has been pretty well settled, although not to his satisfaction. During the Dover Trial he [Behe] faced over 50 scientific publications that dealt with his examples and proved that they are not irreducibly complex. His response was “That’s not enough.”

His biggest mistake is an assumption, he is assuming that the mechanisms have to appear suddenly, completely intact. Behe needs to say something similar to Darwin, “If it could be demonstrated that a complex organ exists which could have been formed by numerous successive slight modifications, my idea of Irreducible Complexity would absolutely not apply.” He has yet to find such a mechanism.

Interestingly that during the trial he admitted to not looking and that no one is doing any experimentation to look! All he’s done is select some mechanisms that hadn’t yet been explained in great evolutionary detail. Charles Darwin speculated the Eye might be tough to explain. He was right, it took decades and many advances in science. Behe listed human clotting factor, the immune system, and bacterial flagellum as irreducibly complex mechanisms. It took less than a decade to refute his claim. Now I guess he will select some other examples and keep making his claims while science catches up. The good thing is Science will catch up!

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