Sunday, July 16, 2006

Some common misperceptions about biology

I just finished reading American Theocracy by former Republican strategist Kevin Phillips. Phillips is one of a dying breed - the moderate, Northeastern Republican, and part of his book harshly criticizes the fundamentalist takeover of his party.

Naturally, evolution and intelligent design come up in the book, and naturally, Phillips is appalled that this is even an issue in the 21st century.

Phillips echos some common misperceptions though, and these misperceptions have to be corrected every time they come up.

Here is Phillips:

"...a recent report by genome researchers found that chimpanzees and humans share a very similar genetic blueprint - a 96 percent overlap, which scientists call overwhelming evidence of Darwin's theory of evolution."

First, chimps and humans share 98.8% of their DNA sequence (although there are also some large-scale chromosomal rearrangements, but these don't impact the actual DNA sequence of homologous regions). If the chimp genome had only a 96% similarity, this would have caused major problems with our current understanding of human evolutionary history. That is too much change in too little time.

Second, the high overlap between chimps and humans wasn't news when the chimp genome came out - we basically knew the 98.8% figure already from numerous studies over the last few decades.

Third, the chimp genome didn't present significant new evidence for evolution. It is helping us to better understand evolution, but in terms of whether evolution happened or not, the chimp genome adds little because there is already such overwhelming evidence out there of a similar nature. You can't say "Look, we sequenced the chimp genome, and now we have more irrefutable evidence of evolution!" That would be like someone saying "my research gives us even more evidence for atoms!" The existence of atoms or evolution is not scientifically in doubt.

Fourth, I get tired of people referring to "evidence for Darwin's theory of evolution," because it makes it sound as if Darwin basically came up with the whole theory, and now we're just looking for evidence for or against it. Evolutionary biology today is no longer Darwin's theory of evolution, any more than modern quantum mechanics is Heisenberg's theory of quantum mechanics. Science advances, and a lot of brilliant men and women have contributed a lot to both theories in their modern forms.

OK, that was complaint number 1. Here is number 2 - Phillips complains that our fight over evolution contributes to our weak science education in this country, but then he later chastises liberals for having too much secular purity and suggests that they should accommodate side by side teaching of ID and evolution.

The problem is, there really isn't much difference, if you're concerned about science education, between teaching ID instead of evolution and teaching both side by side. ID is pure deception - religious ideology dressed up in the language of science. ID has produced absolutely no scientific research. The content of ID consists mainly of criticisms of evolution, criticisms which biologists do not accept as valid criticisms. There are open questions in the science of evolution, but they are not the questions the Discovery Institute is peddling.

Teaching ID, whether along with evolution or instead of it, would both damage the students' understanding of one of the bedrock ideas of biology, and ruin their understanding of how science actually works by pushing ID garbage as real science.

First Amendment issues aside (which Phillips thinks secular purists need to compromise on - we should give in and allow school prayer), any teaching of ID as legitimate science will weaken the science education Phillips is so concerned about.

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