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From www.discovery.org/csc:

Darwinian doubts

The Strength of Natural Selection in the Wild

All Those Darwinian Doubts
By: David Berlinski
Wichita Eagle
March 9, 2005

NOTE: The article below is the full version by Dr. Berlinski. The Wichita Eagle opted to shorten the piece to only 400 words.

The defense of Darwin’s theory of evolution has now fallen into the hands of biologists who believe in suppressing criticism when possible and ignoring it when not. It is not a strategy calculated in induce confidence in the scientific method. A paper published recently in the Proceedings of the Biological Society of Washington concluded that the events taking place during the Cambrian era could best be understood in terms of an intelligent design – hardly a position unknown in the history of western science. The paper was, of course, peer-reviewed by three prominent evolutionary biologists. Wise men attend to the publication of every one of the Proceeding’s papers, but in the case of Steven Meyer’s "The origin of biological information and the higher taxonomic categories," the Board of Editors was at once given to understand that they had done a bad thing. Their indecent capitulation followed at once.

Publication of the paper, they confessed, was a mistake. It would never happen again. It had barely happened at all. And peer review?

The hell with it.

“If scientists do not oppose antievolutionism,” Eugenie Scott, the Executive Director of the National Center for Science Education, remarked, “it will reach more people with the mistaken idea that evolution is scientifically weak.” Scott’s understanding of ‘opposition’ had nothing to do with reasoned discussion. It had nothing to do with reason at all. Discussing the issue was out of the question. Her advice to her colleagues was considerably more to the point: "Avoid debates."

Everyone else had better shut up.

In this country, at least, no one is ever going to shut up, the more so since the case against Darwin’s theory retains an almost lunatic vitality.

Look – The suggestion that Darwin’s theory of evolution is like theories in the serious sciences – quantum electrodynamics, say – is grotesque. Quantum electrodynamics is accurate to thirteen unyielding decimal places. Darwin’s theory makes no tight quantitative predictions at all.

Look – Field studies attempting to measure natural selection inevitably report weak to non-existent selection effects.

Look – Darwin’s theory is open at one end since there are no plausible account for the origins of life.

Look – The astonishing and irreducible complexity of various cellular structures has not yet successfully been described, let alone explained.

Look – A great many species enter the fossil record trailing no obvious ancestors and depart for Valhalla leaving no obvious descendents.

Look – Where attempts to replicate Darwinian evolution on the computer have been successful, they have not used classical Darwinian principles, and where they have used such principles, they have not been successful.

Look – Tens of thousands of fruit flies have come and gone in laboratory experiments, and every last one of them has remained a fruit fly to the end, all efforts to see the miracle of speciation unavailing.

Look – The remarkable similarity in the genome of a great many organisms suggests that there is at bottom only one living system; but how then to account for the astonishing differences between human beings and their near relatives – differences that remain obvious to anyone who has visited a zoo?

But look again – If the differences between organisms are scientifically more interesting than their genomic similarities, of what use is Darwin’s theory since it’s otherwise mysterious operations take place by genetic variations?
These are hardly trivial questions. Each suggests a dozen others. These are hardly circumstances that do much to support the view that there are “no valid criticisms of Darwin’s theory,” as so many recent editorials have suggested.

Serious biologists quite understand all this. They rather regard Darwin’s theory as an elderly uncle invited to a family dinner. The old boy has no hair, he has no teeth, he is hard of hearing, and he often drools. Addressing even senior members at table as Sonny, he is inordinately eager to tell the same story over and over again.

But he’s family. What can you do?


The Strength of Natural Selection in the Wild
By: David Berlinski
Discovery Institute
April 25, 2005

Like Hell itself, Darwin’s theory of evolution is often said to be protected by walls that are at least seven miles thick, in that it is not only true, but unassailable. It is a considerable irony, therefore, that some of the most cogent criticisms of Darwin’s theory are the result of work undertaken by very orthodox members of the biological establishment itself. Such criticisms are inevitably designated as calls for further research. They are, nonetheless, what they are.

A recent study by J.G. Kingsolver et al (hereinafter Kingsolver) entitled The Strength of Phenotypic Selection in Natural Populations, published in the March 2001 issue of The American Naturalist, is an interesting example. It is field studies of natural selection that is at issue in this study. Such studies are addressed to living species under natural conditions, and it comes as something of a surprise to learn that despite very long-standing claims by evolutionary biologists to have established the robust viability of natural selection as a biological force, the overwhelming number of such studies have been conducted only in the past fifteen years.

Kingsolver’s study is second-order in nature: It analyses and discusses sixty three field studies dealing with sixty two species that have been reported in the literature since the publication of J.A. Endler’s well-known monograph, Natural Selection in the Wild, published in 1986.

The statistical methods by which Kingsolver proceeded are simple to the point of triteness. One the one hand, there are a series of quantitative biological traits, chiefly morphological in nature; and on the other hand, certain quantitative measure of fitness. Beak length in finches is a typical morphological trait, and survival, mating success or fecundity typical measure of fitness. Using the methodology first introduced by R. Lande and S. J. Arnold in their 1983 study, ‘The Measurement of selection on correlated characteristics,’ published in Evolution, 37, Kingsolver proposed to define selection in terms of the slope of the regression between a quantitative trait of interest and specific measures of fitness. This provides an estimate of the strength of selection.

Natural selection disappears as a biological force and reappears as a statistical artifact. The change is not trivial. It is one thing to say that nothing in biology makes sense except in the light of evolution; it is quite another thing to say that nothing in biology makes sense except in the light of various regression correlations between quantitative characteristics. It hardly appears obvious that if natural selection is simply a matter of correlations established between quantitative traits, that Darwin’s theory has any content beyond the phenomenological, and in the most obvious sense, is no theory at all.

Be that as it may, the real burden of Kingsolver’s study lies in the quantitative conclusions it reaches. Two correlations are at issue. The first is linear, and corresponds to what in population genetics is called directional selection; and the second quadratic, and corresponds either to stabilizing or disruptive selection. These are the cornerstones of the modern hill and valley model of much of mathematical population genetics. Kingsolver reported a median absolute value of 0.16 for linear selection, and a median absolute value of 0.10 for quadratic selection. Thus an increase of one standard deviation in, say, beak finch length, could be expected to change fitness by only 16 percent in the case of linear selection, and 10 percent in the case of quadratic selection. These figures are commonly understood to represent a very weak correlation. Thus if a change in the length of a beak’s finch by one standard deviation explains 16 percent of the change in the population’s fitness, 84 percent of the change is not explained by selection at all.

These results, although at odds with those reported by Endler, are not in themselves astounding. It is when sample sizes pass beyond samples of 1000 that results become far more difficult to accommodate, for under these circumstances, Kingsolver reported, both linear and quadratic selection were virtually non-existent.

The significance of these results is, of course, not entirely clear. Kingsolver goes no further than observing that “important issues about selection remain unresolved.” Considering the fundamental role of both linear and quadratic selection in population genetics and in popular accounts of Darwin’s theory, one of those “unresolved” issues may well be whether natural selection exists to any appreciable extent, and if it does, whether it plays any real role in biological change altogether.

These considerations may assume some importance when it comes to assessing the widely repeated claim that Darwin’s theory is as well-established as physical theories such as general relativity or quantum mechanics