Intelligent Design: Skeptical Thoughts about the Skepticism (2)

In my last column I distinguished between evolution and natural selection, which is the supposed mechanism by which evolution is accomplished. Evolution is established beyond question, in my opinion, but not natural selection. The crucial question is: What is the cause of evolution- natural selection? Intelligent Design? something else?
I bemoaned the weakness of some of the arguments put forth by those scientists who argue for natural selection against Intelligent Design, and I critically examined three of their claims: that Intelligent Design is inherently unscientific; that to abandon natural selection would be to abandon the basic framework of biology; and that we see natural selection all around us as in the genesis of new strains of germs.

In this column I will look at some other points that make me dubious about the natural-selection position.

The Case of the Peppered Moth. As a theory, natural selection has an obvious weakness, namely, that it is difficult if not impossible to prove. To demonstrate decisively that natural selection is the cause of evolution, we have to manipulate nature in such a way as to show that evolutionary change occurs when, and only when, natural selection occurs. That is a tough assignment.

So the world of biology was thrilled to learn of a set of experiments performed in 1953 by an English doctor-turned-naturalist named Bernard Kettlewell.

Kettlewell's experiments involved the peppered moth, of which there were two forms. The more usual (called the "typical") is cream-colored. The other form is black (melanic). This melanic form had first appeared in Manchester, England, during the mid-1800s when the Industrial Revolution produced enormous clouds of pollution that literally blackened the atmosphere and the landscape. The melanic form thrived in these surroundings, and it seemed logical to suppose that it became predominant over the cream-colored form because in the dark soot-covered environment it was better able to survive and reproduce- in other words, through natural selection.

Kettlewell aimed to prove the truth of this supposition in a scientifically rigorous manner. His hypothesis was 1) the melanic moths would be better camouflaged on tree trunks that had been darkened by pollution, while the lighter cream-colored moths would be better camouflaged on trees in their original state, and 2) birds would eat a larger percentage of uncamouflaged moths. (Birds were the "agent of selection.") Therefore more melanic moths would survive in a polluted area, and more cream-colored moths would survive in a pristine area.
He conducted his experiment in two stages, one in a polluted area and one in a non-polluted area. First he marked a number of each kind of moth. Then he placed the moths of each kind on tree trunks. Finally, he recaptured the moths, noting how many of the marked and recaptured moths were lighter-colored and how many were melanic. (He assumed that the proportion of each kind of moth recaptured was equal to the proportion of that kind that had survived the assaults of birds.)

And sure enough, in the dark soot-covered environment, about twice as many melanic moths were recaptured, while in the pristine environment, about three times as many of the lighter-colored variety were recaptured! Each variety of peppered moth had won out (i.e. had been "selected") in its favored environment!

So the peppered moth became the prime exhibit for natural selection. Kettlewell's experiments were hailed as demonstrating natural selection in action and thereby proving that natural selection was indeed the engine of evolution. They became standard fare in textbooks, and biologists and biology teachers cited them as the proof of evolution through natural selection.

Let's pause and assume that these experiments are trustworthy. Then let's ask whether they do indeed prove that natural selection is the engine of evolution. Two points are worth noting:

1) A single set of experiments regarding a single instance of natural selection is cited as proof of the entire theory. This is a weak reed to rest the theory on, and the fact that the one set of experiments is made to bear such a heavy burden should be cause for suspicion.

2) The experiment shows us the proliferation of the melanic form of peppered moth, but tells us nothing about its origin. According to evolutionary theory, a new species begins with a random mutation that provides the means for an individual organism to thrive. But Kettlewell's experiments have nothing to do with the origin of the melanic peppered moths. These moths are already on the scene when he begins his experiments; for all we know, they could be the product of Intelligent Design.

So the Kettlewell experiments do little to prove the theory of natural selection, but they do much to show how the supporters of natural selection can jump to conclusions.
I get the impression that the scientists who support natural selection against Intelligent Design are very good at doing science, but not very good at thinking about science.
But in any case, Kettlewell's experiments were not what they seemed. Recent scrutiny has shown them to be deeply flawed at best, as described in Of Moths and Men by Judith Hooper. Here are some of the main defects, as described in her book:

The number of moths Kettlewell set on the trees was far above the number that would settle on the trees naturally (he set up a "bird feeder"); thus birds were much more attracted to them than in a natural setting. (pp. 243, 254)

The natural resting place for moths is not on the tree trunks, where Kettlewell placed them, but on the undersides of branches, where they would be less vulnerable. (p. 260)

Kettlewell twice changed his methodology during the course of the experiment when the results he was getting failed to match the results he expected and desired. (p. 254)

These flaws were summed up in the quip that Kettlewell's experiments demonstrated "unnatural selection." (pp. 267, 284)

Finally, the experiments have not been satisfactorily replicated. (p. 262-263)

In short, Kettlewell's experiments are not reliable, and even if they were reliable they would serve at most as an illustration of how natural selection might occur, not as proof that it is responsible for the entire process of evolution.

Random mutations. The theory of natural selection holds that new species originate when random mutations in the genes of one or a few individuals make these individuals better adapted to their environment.

But random mutations hardly ever occur. We don't see people or animals randomly born with two noses or three eyes. Could there be someone who engineers mutations to get just the ones that He, She, or It wants?

A scientist supporting natural selection might well reply by pointing to DNA and saying that mutations are not completely random but rather can occur only at some definite point on the DNA chain, within well-defined boundaries (e.g. lengthening a bird's bill, not creating a second bill). OK- that sounds reasonable. But let's keep the matter of random mutations in mind.

Then there's the flounder. The flounder is a fish that has both eyes on the same side of its head. That is to say, both eyes are on the same side when the flounder is an adult; when born, its two eyes are on the two sides of its head, and one eye migrates to the other side as the flounder grows up, thus recapitulating its evolution.

Both eyes on one side! If that isn't random mutation, what could be? So where are we on this matter of random mutation? If mutations aren't random, then how explain the flounder? If they are random, then why don't we see more of them?

What I have been trying to point out in these two columns is that opponents of Intelligent Design, in trying to dismiss that viewpoint out of hand, are in danger of replacing religious dogmatism with their own kind of scientific dogmatism. But perhaps this is because they are attacking Intelligent Design at the wrong point.

Although proponents of Intelligent Design may well be sincere in their claims to be doing science, it is clear that they have an extended agenda- they want to prove the existence of an Intelligent Designer because they believe the Intelligent Designer is the Christian God.

Their argument, in effect, is twofold: An Intelligent Designer is responsible for the existence of the species AND the Intelligent Designer is the Christian God. (I would be willing to bet that the proponents' scientific zeal would diminish radically if they had to abandon the second step of their argument.)

In fairness, we should consider the second step as well as the first. Proponents say that the facts of the world imply that there is an Intelligent Designer. If this is true, then what kind of world has the Designer designed? Do the facts of the world also imply that the Intelligent Designer is the Christian God?

I hesitate to go down this road, because in the back of my mind I hear voices saying that I will be attacking the main fabric of many people's lives. But perhaps we have been over-reticent in matters concerning organized religion, and thereby have not only discouraged frank discussion but also provided a sanctuary from which the Religious Right can sally forth to ravage our civic life. So maybe it's time to put truth above courtesy.
At issue is the hypothesis that the characteristics of the world around us show that the Intelligent Designer- assuming there is one- is the Christian God.

There is one insurmountable difficulty with this hypothesis. It is usually termed the Problem of Evil.

The Problem of Evil arises from the supposition that God is all-powerful and all-loving. In addition, He (or She or It) is presumed to be just and, as the Intelligent Designer, supremely intelligent. But these attributes- in particular being all-powerful and all-loving- are inconsistent with the presence of evil in the world. For if the Designer-God could abolish evil but does not, then He is not all-loving. If the Designer-God would like to abolish evil but cannot, then He is not all-powerful. However you look at it, the existence of the Christian Designer-God cannot be squared with the presence of evil in the world.
(For a much more eloquent statement of the problem, read the section titled "Rebellion" in Dostoevsky's The Brothers Karamazov.)

The first line of defense against the Problem of Evil is that evil arises from mankind's misuse of the wonderful gift of free will. There are two fatal flaws in this defense, corresponding to the two types of evil- moral evil (arising from human choice) and natural evil (arising from natural events apart from human choice).

The first flaw is that this line of defense cannot explain natural evil. A six-year-old boy dies of leukemia. What choice has he made- or has anyone else made- that explains or justifies his suffering and death?

And as for moral evil, the suffering that follows from evil choices is all too often inflicted not on the evil-doer but on innocents. To take one gross and obvious example, the Nazis in World War II made many evil choices. Because of these choices the Germans bombed London and the Allies bombed Hamburg, Dresden and other German cities. Many innocent men, women and children were killed as a result. Are we to say that the death of these innocents is justified by the evil choices of the Nazis?- If so, where is the justice, and where is the love in a God that would allow the slaughter of innocents?

Original sin may be proposed as justification for the slaughter of innocents. The implication is that we are poor benighted creatures who deserve whatever affliction we may suffer, in total disregard of what we have done. Where is the loving God in this scenario? And where is the justice?

The second line of defense against the Problem of Evil is the claim that our earthly life is really unimportant; it is just a waiting-room, or testing-room, for the Afterlife. Thus it doesn't matter that innocent children die totally undeserved deaths, for they are merely going more quickly to their Heavenly reward. If you really believe this, you will get rid of your worldly possessions and retire to a monastery to prove your worthiness while awaiting your time. But more to the point, a God who would test some of us with overwhelming afflictions is a cruel God indeed.

The third line of defense is that the ways of God are a mystery. Bravo! I agree wholeheartedly. The trouble is that some (not all) who proclaim that God is a mystery turn right around and confidently assert that they know exactly how God wants us to live and whom he wants us to oppress.

Why can't those on both sides of the fence simply admit that we don't know?
Read More on Minding the Issues
Volume 2, Issue 1, Posted 08.29 AM / 11th January 2006.