Michael Behe, a professor of biochemistry at Lehigh University, challenges the theory of evolution. In his book, Darwin's Black Box. He sees design on the molecular level of reality. What is design? "Design is simply the purposeful arrangement of parts." The function of the system, he says, is determined from the system internal logic. He reveals the detailed precision and complexity of inner workings of the eye, blood clothing, etc. He calls this irreducible complexity meaning that a single system composed of several interacting parts would stop functioning if you remove any of its the molecular functions.
Electron microscope image of earthworms hemoglobin molecules.
Now, how did these complex designs come about?
Could this have come about by natural selection? There is no one who can show in detail how these purposeful designs could have come about by the biological laws of reproduction, mutation and natural selection.
Can symbiosis explain the origin of complex biochemical systems? The theory is proposed which envisions at the beginning of life a larger cell swallowing a smaller living organism. The larger organism instead of digesting the smaller learned to live in harmony with it.. This does not explain design because it does not explain how the existing cells originated.
Can complexity theory explain intelligent design? "Complexity theory states that systems with a large number of interacting component spontaneously organize themselves into ordered patterns." Michael Behe does not believe this explains intelligent design because this theory is based on mathematical concepts describing the behavior of computer programs which cannot be translated into real life. Secondly, "The essence of cellular life is regulation: The cell controls how much and what kind of chemicals it makes; when it loses control, it dies." (p. 191)
So, Michael Behe concludes: It is entirely possible that these biochemical systems were designed billions of years ago when the designer made the first cell and that they have been passed down through the normal process of cellular reproduction. Such designs as blood clothing were present but were not turned on till later. Such a scenario is probable since we know that even today some genes are recessive but show up in future generations.
In the Origin of the Species chapter dealing with "Difficulties of the Theory", Darwin foresaw this possibility as he states: "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." (Darwin, p. 87)
DNA is Intelligent Design