Not-So-Intelligent Design

Michael Behe is a defender of the so-called "Intelligent Design" theory. This is a purportedly scientific theory which suggests that, since the earth is so cool, it couldn't be an accident. Politically it amounts to an endorsement of creationism and a rejection of evolution. Now I can think of some logical problems with Behe's article, but I'm no evolutionary biologist. Lucky for me I'm married to one, so I asked her.....

Me: So honey, what do you think of Mr. Behe's article?

Her: This article arguing for “Intelligent Design” makes me questions Mr. Behe's credentials as a "Professor of Biological Sciences" at Lehigh University. In fact, let me check out his credentials right now.

(checking on her computer)

Let's see. His page on the Lehigh University website discusses his current research, which is on biochemical aspects of DNA, but his listing of "representative publications" doesn't show a single reputable scientific article. It's all on intelligent design. Let me look up his dissertation.

INVESTIGATION OF SOME PHYSICAL CHEMICAL FACTORS AFFECTING THE GELATION OF SICKLE CELL HEMOGLOBIN. University of Pennsylvania, 1978. Well that certainly sounds respectable. What the hell happened to him?

Me: Drinking too many lab chemicals? Never mind.

Her: He presents the following four arguments for "Intelligent Design":

1. We can often recognize the effects of design in nature.

Huh? How? He says that plate tectonics are enough to explain the Rocky Mountains, but not Mount Rushmore. We can see Mount Rushmore and recognize that it is not nature but design. This does nothing for “intelligent design”, only says that we aren't stupid enough to think that Mount Rushmore appeared naturally. He doesn't give any examples of natural phenomena that he considers to be caused by design.

Me: This is a fallacy called "confusing cause and effect."

Her: 2. The physical marks of design are visible in aspects of biology.

For his evidence, he cites the 18th century clergyman William Paley, who said living things were like a watch. Then he said that science has shown nature to be mechanistic, with cells and molecules behaving in predictable ways. Yes, that is true. But all this tells you is that nature is not random. Of course nature is not random. It is a system; it all evolved from a single source, so of course it all works the same way. People have trouble accepting that natural selection and other natural processes are not random; they can't conceive of things on the time scale necessary to understand evolution.

Me: People generally don't like the idea of the random. If you've ever seen "A Beautiful Mind" you'll recognize how adept human beings are at recognizing patterns that aren't there.

Her: 3. The next claim in the argument for design is that we have no good explanation for the foundation of life that doesn't involve intelligence.

What? As a biologist, I think we have excellent explanations for the foundation of life that don't involve intelligence. Read a book.

Me: What book?

Her: Go to Barnes and Noble to the "Science" section. There will be about fifty of them.

4. In the absence of any convincing non-design explanation, we are justified in thinking that real intelligent design was involved in life.

We are? This is an argument? Publius, help me out with this one; seems more like your realm.

Me: Well, this is another fallacy, called "Burden of Proof." Essentially Mr. Behe is trying to say that he doesn't have to prove intelligent design - that we have to disprove it. Unfortunately for him, science doesn't work that way. Which he should remember from graduate school. If he showed up, that is. Which I doubt.

Her: This guy might know his DNA, he might be very good at biochemistry, but he really doesn't understand natural selection or evolution. Apparently he has been totally wowed by the things he has seen while examining the workings of DNA, and he can't come up with a good explanation for they exist and has had some sort of religious experience. I have learned some amazing things by studying DNA as well, from an evolutionary viewpoint, and I believe they can only be explained BY natural selection, not in spite of it.

Natural selection is dreadfully inefficient, yet it gets the job done. Look closely at any biological system, and you will simultaneously be impressed by how well it works and confused by the many ways you could think of that would work better.

Let's use an example that Dr. Behe should understand very well, considering his dissertation was on the topic: Sickle-cell anemia. This is a disease that kills thousands of people a year, and is found primarily in people of west or central African ancestry. Sickle-cell anemia is caused by a single mutation in one of the genes for hemoglobin, the protein in red blood cells that carries oxygen around your body. This mutation causes the hemoglobin to be very unstable, and when exposed to any sort of oxygen stress (like exercise) the hemoglobin forms rods, which causes the red blood cells to stack up in an unnatural way and clog up your capillaries.

We have two genes for any given trait, one gene from your father and one from your mother. If you have two genes for sickle-cell hemoglobin, you have full-fledged sickle-cell anemia and probably won't live long, at least not without extensive treatment. Many children in Africa die of this every year.

If you have two normal hemoglobin genes, you're fine. So why is sickle-cell so common? In some African populations, as many as 20% of people have it. Natural selection should get rid of this disease since it's clearly not adaptive.

Well, I'll tell you why. A little thing called malaria. This disease, which kills millions each year, is caused by a parasite transmitted by mosquitoes that infects and reproduces in your red blood cells. If you've got the gene for sickle-cell, the presence of this parasite causes stress which in turn causes the cell to sickle and destroy itself, thus destroying the malaria parasite. Ta-da! No malaria.

If you have one gene for sickled hemoglobin and one gene for normal hemoglobin, then you are doing just fine in Africa, because you won't suffer from sickle-cell anemia (because about half of your red blood cells are normal) OR malaria (because half will sickle). Perfect, right? No. Because you can't guarantee that your kids will each get one normal and one sickled gene. Even if your spouse has one of each, the kids get your genes randomly. There's a 25% chance that your kids will have sickle-cell anemia and die, and another 25% chance that your kids will have normal hemoglobin and die from malaria.

That doesn't sound like intelligent design to me.

Me: Me neither.