The other day I said I had a problem with the theory of evolution. I broke the theory into two parts, which I called the Weak Theory and the Strong Theory. I said I was OK with the Weak Theory. That's the part that says we can trace our ancestry all the way back to the primordial slime. Who but an ignorant hillbilly could doubt that, in the light of the massive scientific evidence?
No, I'm not going to argue with the Weak Theory. It's the Strong Theory that gets me. I said I was going to hold off for a day or two and see if anyone could guess what I mean when I talk about the Strong Theory. Well, time's up.
The Weak Theory says,"this is exactly what happened". The Strong Theory says we know how and why it happened. The intricate development of millions of different life forms occurred through the mechanism of random errors in the transmission of the genetic code. The overwhelming majority of such transmission errors would naturally be harmful if not fatal; but here and there, it results in a characteristic which is useful. The bearer of this characteristic is more likely to procreate than his "normal" siblings, and the new characteristic is thereby incorporated into the gene pool of the population, where over time it ultimately dominates and becomes the new norm.
Is there one single scrap of scientific evidence to support the Strong Theory? In school we learned about the grey moths and the white moths. It seems that 99% of the moths used to be white, but during the Industrial Revolution smog coated everything in London with a layer of grey; the white moths became easy prey for birds, and as a result now all the moths are grey. Evolution at work.
But there were already grey moths in existence. The characteristic of interest was already present in the gene pool. Where was the random mutation that supposedly created it? There was none, because the gene already existed.
How does a brand new trait come into existence? That's a tough one. The much-maligned proponents of Intelligent Design like to talk about the problematic case of the human eye, and rightly so. There was once a time when not a single organism was sensitive to the presence or absence of light. They were all just blobs floating around in the ocean, and when one of them bumped into another, presumably the bigger one would wrap itself around the smaller one and mulch it down into digestible bits. A case of the blind eating the blind.
Now, what does the Strong Theory tell us? That somehow, one of these blobs laid its blob-eggs somewhere, and a cosmic particle came along and messed up the DNA in one of the eggs. The result was that a baby blob was born who was different from all the other blobs: somewhere on the surface of its body, there was a little patch of skin that contained photo-sensitive chemicals: compounds that would change state when exposed to light, and change back again when the light disappeared. Quite a trick for a random cosmic particle.
But that's not nearly enough. Somehow this patch of skin had to be hooked up to whatever rudimentary brain this blob must have possessed: the blob had to know that it was sensing light. The blog had to know that this tingling on its skin meant light, and it had to want to swim towards the source of that tingling, because perhaps there was more food to be had in that direction. By eating more food, the blob got bigger, and that made him more likely to survive in his blob-eat-blob world to the age of procreation. And his photo-sensitive offspring, over time, came to rule the world of the blobs through their inherent superiority.
So let's recap all the things that had to happen in a single generation for this genetic mutation to have taken hold. First, you needed the appearance of photo-sensitive compounds. This doesn't just happen by shooting a cosmic particle at a piece of DNA: the DNA doesn't become light sensitive. The DNA is a kind of a blueprint that creates an enzyme, and it is this new enzyme that manufactures the photo-sensitive chemical. But that's not enough. This new chemical, which is presumably just floating around in the protoplasm, has to somehow stimulate whatever locomotive mechanism this blob uses to propel itself around. It doesn't do any good to have a mutation which does one without the other.
That doesn't begin to address the question of how the blob is supposed to know whether it wants to swim towards the light or away from it. But never mind. Let's suppose it all works: that a single cosmic particle disrupts the genetic code in just the right way so that these three simultaneous, highly improbable developments occur (and without accidentally killing the blob in the bargain). The hard part is behind us; we've initiated the evolutionary chain, and now it's only a matter of time before this primitive photo-sensitive blob, the ancestor of us all, evolves into the myriad of life forms with the sophisticated organs of vision which we are all familiar with. Right?
The Creationists like to talk about a hurricane blowing through a junk yard, and when the dust has settled you find that by randomly flinging one piece of metal against another, it has managed put together a Boeing 747. I'd say this is a pretty close to how the Strong Theory explains the evolution of the human eye. I know that saying this brands me as an ignorant hillbilly, but if the shoe fits I might as well wear it. I'd just like to throw one more wrinkle into the story of vision. It's the question of color.
Not all mammals have color vision. Presumably we humans have some ancestor who saw only black and white. What does the strong theory tell us? That somewhere along the line, a random mutation produced an individual with color vision, and because of his superior skills, his progeny came to dominate the gene pool over time.
A random mutation produced an individual with color vision? That's some cosmic particle we're talking about. Because anything less than a fully developed sense of color vision couldn't have been all that useful. Do you have any idea how much more complex a color TV is as compared to black and white? There are three different receptors, and there's all kinds of signal processing you've got to handle all of a sudden, and its a huge complication. And you can't argue that it came about gradually, because what kind of benefit is there to the individual who can see just a little red?
Come to think of it, how much of an advantage is color vision even when fully developed? Yes, it's nice to have, but it's not clear to me how an individual born out of the blue with the miraculous gift of color vision would have had all that much advantage over his black-and-white fellows. There were no color-coded electrical wires to worry about back then; yes, you could more easily tell the difference between a blackberry and a raspberry, but aren't they both delicious after all? I'm not saying it wouldn't have come in handy now and then, but to the extent that one such individual would ultimately dominate the whole gene pool? I just don't buy it.
The thing that bothers me the most about the whole evolution thing is that it's taken as a litmus test for admission into decent society. Question any aspect of the theory and you're branded as an ignorant hillbilly. Why is this?
I think it's because the proponents of evolution really want to use it as a weapon against religious faith. That's why the Strong Theory is so important to them. The Weak Theory is, after all, fully compatible with the idea that God has guided the process along with the intent of creating us in his image. But that's not good enough for the evolutionists. They demand that we acknowledge the random nature of the process, so that there is clearly no role for a Creator in their world-view. And if that means they have to argue for a Strong Theory that by its very nature cannot possibly have any scientific evidence to back it up, then so be it.
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