So I promised to take a look at some of the popular ideas opposed to Neo-Darwinian evolutionary theory.
“Young earth creationism” or other schools of thought that try to read the creation stories of Genesis (there are two) as scientific texts just aren’t serious. I’ve only met one adult who believed in it so I can’t think it is as popular as people say. It also is important to point out that in the history of Christianity Biblical literalism has rarely been a mainstream phenomena. For about 1500 years the common opinion among Christian theologians was that some bits of the Bible are meant to be taken literally, others as history, others as poetry, others as homilies, etc. Literalism has become more popular since the Reformation, in part as a reaction against modernity, in part as an expression of modern man’s quest for clear and certain knowledge. Modern man had a hard time understanding that truth is a many-layered thing, and this seems to have rubbed off on some Christians. Enough about Biblical literalism.
The other, more serious option tossed around is Intelligent Design Theory (ID Theory). ID Theory has a harsh critique of neo-Darwinism that goes something like this: a single life form is composed of several interdependent systems which cannot exist apart from one another, and each of these systems is composed of various interdependent parts. This is called irreducible complexity: each part serves a purpose only in reference to the others. Therefore no one of the parts can evolve on its own, they all have to evolve together. But evolving together implies that they evolve, not by chance, but with a purpose.
For example: An eye is a system (lens, muscles, retina, nerves…). Take away a piece, and it stops working; it does not help the animal survive, and the animal will not reproduce. So either the elements of the eye evolved all at once or they never evolved at all. A snail with a lens but no retina will not pass the lens onto the next generation, so retinas and lenses could not have evolved at all. The eye is part of a larger system called sight, by which electromagnetic waves reflecting off objects are translated into electro-chemical impulses which the brain uses to reconstruct a 3-D image of the surrounding world by which we can walk around without bumping into things. An eye is useless without reference to this larger system.* It cannot randomly come about through mutation and the survival of the fittest.
Where the wheels fall off the ID bus, however, is when they propose to save the theory of evolution by trotting in God. I’m not saying that God can’t be an intelligent designer, but that is not a scientific answer to a scientific problem. What ID does is point out that a scientific theory is inadequate, but then re-proposes the same inadequate theory + God. It would be like Galileo correcting Aristotle’s notion that objects with greater mass fall faster by saying “They do fall faster, but little angels slow down the big objects so the little objects don’t feel bad and everyone wins the race.”
I think that when faced with the question “how does an irreducibly complex system like sight, which to this day we do not really understand, evolve into existence”, the only honest answer is to say: “We don’t know.”*
If neo-Darwinian theory cannot answer the ID critique, there is nothing wrong with scrapping the theory and trying to come up with another one that explains how wolves and dingoes are members of the same species, but not foxes. It will not be necessary to dump what we know about paleontology, comparative biology and genetics, but to reinterpret it. That is what used to be called “scientific progress.
* The eye example and “We don’t know” answer is lifted from The Deniable Darwin, an article by David Berlinski in Commentary Magazine, 1996. I have mixed feelings about the article, but between it and letters to the editor it caused you can get a good all around view on the popular debate.
Next time: Which side will you choose? Order or Chaos?