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.