THE FLAGSHIP EXAMPLE of natural selection in the popular and classroom biology of my youth was the supposed adaptation of British peppered moth reportedly going from a light colored variant to a dark one, supposedly as a result of the appalling air pollution caused by Britain's reliance on the burning of coal, light colored moths on soot blackened tree bark falling prey to predators, killing them off before they got a chance to breed, so passing on their genes for dark pigmentation and it becoming dominant in succeeding generations. It appeared in some of the textbooks of high school science and in my tenth grade biology textbook and was taught to children of my generation as science "proving the reality of natural selection." Well, if that bit of lore hasn't gone into the boneyard of discontinued science on a popular level, as you, dear Darwin defender proves in citing it, I doubt any scientists who know what they're talking about would bring it up in the way you did.
This description of the scandalous violation of scientific method is not comprehensive, it doesn't give what I think are some of the most obvious problems with the study of the problem, such as leaving out the far longer pupal stage of the lives of the moth in which the coloration of the two variants could not account for the reported observations in the shorter adult lives of the creatures. But it's enough to demonstrate what I disagreed with in Eddington's idealistic description of physical science as done about far smaller, far simpler, perhaps more uniformly existing particles but which goes under the same name.
The idea that natural selection might explain the rise of the dark moths was suggested in the late 19th century. But it wasn't tested until 1953, when E. B. Ford, an Oxford biologist, recruited an amateur lepidopterist, H. B. D. Kettlewell, to get out into the field and find out what was happening. Kettlewell, a doctor, and a moth collector since he was a boy, jumped at the opportunity to abandon his medical practice and pursue his hobby full time.
He lugged mercury-vapor lamps and moth traps into the English countryside, where he released thousands of moths and monitored their survival. The experiments were difficult, but within two years Kettlewell had the evidence Ford was looking for. In industrial areas, birds gobbled up the typical peppered moths, leaving the dark moths behind to reproduce. That explained why the population of dark moths was increasing. And the opposite happened in undisturbed forests -- the dark moths were eaten, and the typicals survived.
''It is the slam-dunk of natural selection,'' Judith Hooper writes in ''Of Moths and Men.'' The experiments made their way into all the evolution textbooks, many of which reproduced a now famous pair of seemingly indisputable black-andwhite photographs. In one, a dark moth is strikingly obvious on a lichen-covered tree trunk, while an arrow points to a nearly invisible speckled moth nearby. In the other, the speckled moth stands like a beacon on a dark, stripped trunk, and the dark moth is neatly concealed.
There it was: natural selection in action. Darwin was right. End of story. Sadly, as Hooper shows, that wasn't the end of the story. In recent years it has become clear that the evidence on which the story hangs is as flimsy as a butterfly's wing. Kettlewell's experiments proved nothing. The most famous example of evolution in action must now become the most infamous.
Kettlewell went into the woods knowing the results he wanted, and he didn't quit until he got them. The experiment was done under highly artificial conditions. Laboratory-bred moths were put on trees in unnatural positions, at the wrong time of day. Kettlewell himself decided which moths were safely concealed from birds and which were not. He was so adept in the field that even his critics might say he could think like a moth. But nobody believed he could see like a bird. ''We don't allow experiments like this any more,'' says Ted Sargent, an emeritus professor of biology at the University of Massachusetts, Amherst, and Kettlewell's severest critic.
Sargent doesn't suggest that Kettlewell lied or cheated. In Kettlewell's desperation to succeed, and to please Ford, he might simply have seen what he wanted to see. ''There are subtle ways to seduce yourself,'' Sargent says. Hooper's aptly titled book is about the men as much as about the moths. The characters in this tragic tale were among Britain's most brilliant scientists. But that brilliance was undermined by cold ambition that led them to turn on one another and perhaps even tamper with results of experiments. Hooper shows us their failings, but with gentleness and respect, creating a moving and compassionate portrait of Ford, Kettlewell and the others in this decades-long drama.
The most sympathetic figure here is Kettlewell. Ford brought him to Oxford because he was the best field lepidopterist Ford knew. Ford was on a mission, to demonstrate the importance of natural selection in Darwin's theory. But Kettlewell was never accepted at Oxford. He did not have the requisite academic degrees, nor could he compete in the often cruel intellectual jousting common in college dining halls. ''He was the best naturalist I have ever met, and almost the worst professional scientist I have ever known,'' said one colleague.
Kettlewell's personal life crumbled as he struggled to meet the increasing demands placed upon him by Ford, whose reputation owed much to his analysis of Kettlewell's experiments. Ford used him up. Kettlewell, a hypochondriac, increasingly began to suffer from real diseases: recurring bouts of bronchitis, pneumonia, pleurisy and flu, along with heart problems. In 1978, he fell out of a birch tree on a collecting expedition, breaking his back. He never recovered. More than anything, Kettlewell wanted to be accepted as a fellow of the Royal Society. Ford nominated him three times, but did so in a way that made sure Kettlewell would not be accepted.
Kettlewell died on May 11, 1979. The Dictionary of Scientific Biography says he ''apparently'' overdosed on a painkiller. But Kettlewell's colleagues knew his death was no accident, Hooper says. Many obituaries expressed enormous affection; ''everyone loved him,'' one said. Everyone except Ford, that is. Told that Kettlewell had committed suicide, Ford called him a coward.
The story of the peppered moth, as Hooper shows, is not what it seemed. Nor is it settled. The dark moths have now nearly disappeared, but the debate continues. ''At its core lay flawed science, dubious methodology and wishful thinking,'' Hooper writes. ''Clustered around the peppered moth is a swam of human ambitions, and self-delusions shared among some of the most renowned evolutionary biologists of our era.''
While there are some real a-holes in the hard physical sciences, I've got to say those in the life sciences, especially surrounding the atheist strongholds of evolutionary biology, psychology, sociology, anthropology are some of the biggest and most revolting a-holes there are. I know, I've known biologists and they complain about their colleagues in those terms surprisingly often. I think there's something in the treatment of human beings and animals as objects that leads either such people to take up those fields or attracts such people to them. Though, me not being prone to claiming scientific knowledge where I know it isn't, wouldn't claim there was any way of testing such a nasty suspicion about the culture of the life sciences and the pseudo-sciences of alleged behavior. It's just a suspicion on my part.
Natural selection is an ideological imposition on the real scientific study of evolution, it's adoption and maintenance, universally enforced as a required ideology to work and be held respectable in the profession of science is an even bigger scandal than this little example of how its inadequate basis in the actual establishment of it in the disinterested observation of nature is lacking and the larger truth that only the tiniest fraction of the actual thing, evolution, almost all of which is forever lost in the billions of years of its history, will ever be vulnerable to honest scientific methods, so much so that there will never be any adequate explanation of any of it, the claim that "its cause" will ever be known one of the most dishonest ever made as science or in intellectual history.
If I had the time I would expand on the same kind of criticism of reliance on artificial conditions to make claims about evolutionary history. One of the most habitually honest of evolutionary biologists, the geneticist Richard Lewontin once made the observation about his main teacher, the eminent geneticist Theodosius Dobzhansky, that his work with fruit flies was all done in the lab and not in natural conditions - it is enormously difficult to study such things in nature and I doubt much of any precise and accurate information could ever be honestly published asserting more general claims from it. Lewontin also has written about what the biological scandal of the peppered moth study tells us about the confidence level that should be placed in scientific claims surrounding the study of evolution, he is, in fact, one of the better internal critics of his own field. Yet he was the object of criticism by the late Lynn Margulis who noted that after a talk he gave about his own work in population genetics that it was, as well, not unambiguously demonstrated in the actual field and was the product of highly artificial, I would gather highly theoretical and mathematical speculation. To get back to the many uses of mathematics to, perhaps, create what may or may not be there. But I don't have time to chase down all of the citations to show that. You're going to have to take my word for it unless you want to fact check me, or not, as you choose to believe or not.
Update: Rereading this for corrections not previously caught, I wondered if the fable of the peppered moth demonstrating Darwinian natural selection in action is still being peddled and, yep, as in Science News for Students.
Since I didn't mention one of the biggest problems for this as an example of natural selection THAT IS THAT THERE WAS NO EVOLUTION OF SPECIES IN THE JUST-SO STORY, THE VERY THING WHICH NATURAL SELECTION IS ALLEGED TO EXPLAIN, there, I just pointed it out. That is obvious from even this updated version of it in which, as Brits gave up burning coal the color change is supposed to have reverted back to a pre-industrial revolution distribution, though I wonder how they would study that in any precise way without having a representative sample of those long ago dead moths.
Naw, evolution is too complex, its raw material too much lost forever in the past for scientific method to be applied to it. Its study will always generate self-interested lore to fill in the gaps and even more so it will be materialist ideology that is shoved into those gaping chasms.
Update 2: I should have noted that the survival of lichen on soot covered trees figured into the folk tale of evolutionary science, maybe even more so than the version that I was told about soot which, as I recall, didn't mention lichen. Just to try to be accurate.
Update 3: NO, no, no, no, no, no. Victorian era butterfly collections are not a representative sample of the distribution of anything in nature, they are a humanly chosen collection. How many insects damaged in collection and discarded in the field, how many disposed of because they were insufficiently unlike a previously collected, murdered and mounted specimen already had, how many not put into the case for other reasons BY THE PERSON MAKING THAT CHOICE would account for what we've got now. And you'll never know what those animals not caught and included were like. I wonder if anyone has ever speculated that stupider or just slower or more enfeebled individuals are over-represented in such collections or maybe it's an unrepresentative sample due to mere chance that didn't happen to give you a representative sample of what tiny part of that species lives you want to write about.
No, the study of life available for inspection is enormously complex, I don't think it makes much sense to include it with the gooviest theoretical physics being done today under the same name, "science". The poverty of our language covers up a hell of a lot of discrepancy like that, especially in academic language that wants to generalize about everything.
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