Thursday, January 19, 2006

What is evolution, anyway?

Evolution is a change in allele frequencies over time. Yes, it is a diabolical concept isn't it. That's right, the proportion of people with light skin in the United States may decrease after several generations because of skin cancer. Does this actually turn anyone's world upside down? I've grown weary of hearing otherwise rational, cultured, and educated people sound like kindergarten students when talking about, and often decrying evolution. The more cunning lot prefer to seize upon the nebulous diction that surrounds this area biological studies. It is hard not to find humor in statements like "of course evolution exists, we know that, but Neodarwinism was invented by liberal atheists to destroy the world." Does anyone know what in God's name Neodarwinism is? I have no idea and I've never even heard the word in an academic setting. Darwinism, while still amorphous in my mind at least has some unanimity in the precepts held in its name. Darwin was an intelligent man who enjoyed natural history. He was probably the first to postulate that organisms adapt to their environments over time; however, by the time he was ready to publish his conclusions, Alfred Russell Wallace, a Briton who had done extensive fieldwork in the East Indies, had reached the same conclusion. Darwin's ideas reflected a natural zenith in thought that saw its academic genesis in the minds of people like Lamarck, Cuvier, and Lyell.

It is true that not all of Darwin's statements were technically correct. After all, he was without the aid of modern genetics and the modern understanding of heredibility developed by the Augustinian Canon, Gregor Mendel. Darwin accepted the idea of blended inheritance, in which idea unique alleles are not preserved from generation to genertation. Mendel proved this to be wrong. However in my opinion, no reasonable scholar could possibly discredit Darwin's entire body of thought because he wasn't able to comprehend the mode of genetic inheritance.

There are two types of evolution. One type results in changes in allele freuquencies over time dictated by differences in survival and fitness of individuals possessing different alleles. This type of evolution generally results from natural selection. An example would be clines in skin color between latitudinal regions. People tend to be dark skinned in equatorial regions and lighter-skinned at higher latitudes.
The other type of evolution is non-adaptive. Methods of non-adaptive evolution include genetic drift, inbreeding, bottlenecks, and others. The basic idea is that there are still changes in allele frequencies, but they don't result in an organism being better adapted to its environment.

I'm really not an expert on evolution and evolutionary theory. It is not my focus in biology. But when I hear how many people have no clue what the hell they are talking about I feel like a genius. Don't be one of the people that sounds like an idiot and learn about the basics of evolution so you can make an intelligent decision. I guess the same is true of all disciplines...except quantum mechanics. Just believe whatever people tell you about quantum mechanics and you won't be any worse for it.