Those Elusive Beneficial Mutations

Naturalists claim that evolution is driven by beneficial mutations. Is that a plausible explanation for the diversity found in nature? Let's check it out.

Induced Mutations

Noted geneticists, Thomas Morgan and Herman Muller conducted a prolonged study of fruit flies (drosophila) looking for traces of evolution. But generation after generation, the uncooperative flies refused to evolve. Eventually they solved the problem, or at least they thought so. They subjected a pure strain of fruit flies to chemical and radiation treatments. The result was mutilated flies. Flies developed yellow, brown, or purple eyes; or bulging, flat, or dented eyes. Some flies had no eyes.

Other abnormalities appeared. Flies came with fine or coarse hair, or curly or ruffled hair. Then again some were bald. A few flies were without antennae. The variation in their wing patterns was striking. Some wings were broad, others were truncated. Occasionally, the wings were so small, the fly couldn't fly. There were big flies, little flies, active flies, and sluggish flies. The list of oddities goes on.

These mutilations were hailed as a success. Many naturalists claimed the matter was settled once and for all. Mutation is the driving force behind evolution.

Everyone agrees that mutations occur in nature. And these geneticists proved that by chemicals and radiations man could induce mutations. But to say that mutations result in new forms of life is an entirely different matter. The fruit fly experiments certainly don't prove it.

Consider the facts. Most of the induced mutations killed the subjects. Some died immediately; others had shorter life spans. If the fly survived at all, it was often sterile or its offspring were too weak to survive. What mutations weren't harmful were at best neutral, producing only trivial results. None of the mutations could honestly be called beneficial.

These experiments went on for 17 years. What did they really prove? Little more than we already knew. Namely, all living things reproduce after their own kind. Regardless of how those fruit flies were treated or mistreated, the only things they're going to produce are -- other fruit flies. It doesn't seem to matter how many generations are observed.

Considering a new generation of fruit flies matures in less than two weeks, the geneticists in the "fly" room studied over 442 generations of fruit flies in 17 years. They did everything they could think of to make them evolve into something else. They didn't.

Here is a question for you: Do you think those scientists would have abandoned their 17 year project if they still had any hope of engineering a new species? No, I don't believe they would either. Perhaps the most important lesson to learn from the fruit fly experiment is the remarkable stability of this species.

Another question: If positive, or benefical mutations are the driving force behind evolution, why couldn't the "fly" room come up with a single unambiguous positive mutation in 17 years and 442 generations of experiments?

Natural Mutations

What do we know of genetic mutations affecting humans? According to Reader's Digest, ABC's of the Human Body, scientists have identified 1,800 diseases transmitted by defective genes. They claim that of all babies born alive today, an estimated .7 percent suffer from genetic defect inherited from the parents.

But those are the ones who live. Other genetic disorders result in miscarriages. They are dead on arrival and few records and for the most part, no records are kept.

Against the 1,800 known genetic disabilities, plus an unknown number of fatal birth defects, what can we put on the positive side of the human mutation ledger? Not a whole lot. Believe it or not, the best example geneticists can come up with is sickle cell anemia. That, we know, is a genetic error which, without medical treatment, frequently leads to death.

That doesn't sound very beneficial, does it? But in a way, it is.

Sickle cell is found in those parts of Asia and Africa where a severe form of malaria from parasites was and to a great extent still is endemic. Those individuals with one chromosome, either from the father or mother, bearing the sickle cell are immune from both malaria and the sickle cell disorder.

On the other hand, the ones who receive two copies of the sickle cell trait, one from each parent, usually die an early death from the anemia. As you can see, it's a mixed blessing.

Skin pigmentation is occasionally cited as an example of a beneficial mutation. Most authorities disagree. They believe the original population had an assortment of genes allowing a broad range of pigmentation. The intense sunlight of the equator favored those with greater pigmentation. The less intense sunlight of northern regions favored those with less pigmentation.

If that's the case, then we can credit natural selection with pairing down the various populations, however, mutations had nothing to do with it.

Neither sickle cell anemia nor skin pigmentation turns out to be a credible example of beneficial mutations. Mutations harmful effects are obvious, but where are the positive ones?

The World Almanac tells us that the worldwide population numbered around 200 million people in A.D 1. By 1650 that figure climbed to 500 million; 200 years later that figure doubled (1850: 1 billion); it doubled again by 1930 (2 billion); doubled again by 1975 (4 billion); and by 2000 reached the level of 6 billion people.

From 4,000 B.C. when Sumerians began keeping records called pictographs on clay records until today, we have had approximately 6,000 years of recorded history. Several billion people have populated the world during this period. It is interesting to note, over all this time and with all these generations, not even one example of an unqualified beneficial mutation in mankind has surfaced.

If we broaden our scope to include plants and animals, nature has not provided us with any obvious permanent, positive mutations there either. We find no observations of one species mutating into another. And we find no eyewitness accounts of any plant or animal developing a new organ - internal or external.

We are told that all two million or so species of life slowly evolved into their present complex configurations through a series of thousands perhaps millions of genetic mistakes.

All those positive mutations which propelled single-celled organisms into redwoods, elephants, and whales occurred sometime back in the misty dawn before man's watch began. Ever since humans arrived on the scene to record evolution's achievements, it has done nothing but make some minor and superficial adjustments on a few species.

The vast majority haven't changed at all.

Naturalists have a pat answer for this criticism. "Six thousand years is too short a time to see evolution's progress." Perhaps. But that has a hollow ring. If beneficial errors are really the creative force that has made every living thing what it is, then it is reasonable to expect a few straightforward examples to spring up somewhere given six thousand years, two million species, and untold opportunities in the form of people, animals, and plants.

But none have surfaced. Evolution must have been on a holiday for the last six thousand years.

Question to Consider: Could it be that positive mutations have not been observed because they simply don't happen?