Saturday, March 28, 2009

Don McLeroy's Evolution "Quotes"

The mover and shaker behind the Texas anti-evolution push against the science standards is the head of the Texas School Board, Don McLeroy. One of the sections of the standards he has proposed is 7B, which reads:
...describe the sufficiency or insufficiency of common ancestry to explain the sudden
appearance, stasis and sequential nature of groups in the fossil record;
He supported this clause with evidence at the tail end of the document. The complete document is here. The vast majority of the quotes involve mainstream scientists writing about evolution. The problem is that McLeroy has selectively used sentences here and there to bolster his opinions. This is classic creationist misquoting. Stand Up For Real Science has examined the quotes and discovered how badly he has misquoted the scientists involved. Here is one example. McLeroy has on his list of quotes:
"Once established an average species of animal or plant will not change enough to be regarded as a new species, even after surviving for something like a hundred thousand, or a million, or even ten million generations … Something tends to prevent the wholesale restructuring of a species, once it has become well established on earth." Steven. M. Stanley, Johns Hopkins Magazine, Page 6, June, 1982 [Stasis]
Here is what Stanley actually said:
"When studying fossil data, we may at times fail to distinguish between closely similar species within genera, but errors of this sort have no bearing on the question at hand. Even if evolution does occasionally occur by a tiny step, such a small change cannot help explain the major shifts seen elsewhere. If two or more species are nearly identical, then collectively they encompass very little evolutionary change. In short, to explain large-scale evolution, we need to look at large-scale evolution!

Large volumes of fossil data now permit us to make the following generalization: Once established, an average species of animal or plant will not change enough to be regarded as a new species, even after surviving for something like a hundred thousand, or a million, or even ten million generations

There is a paradox here, for using generations as units of time brings us into the realm of population genetics, and the simple fact is that workers in this field have never envisioned the remarkable evolutionary stability that we can now document. Artificial selection favoring certain heritable features has indeed produced substantial restructuring of laboratory fruit flies in only tens or hundreds of generations, and experimental geneticists have always assumed that their fruit fly experiments in principle mimic events in nature. Theoretically, it has seemed a very small percentage of selective deaths in each generation should, over myriads of generations, amount to a total biological remodeling of any species in nature. But the fossil record suggests otherwise: Something tends to prevent the wholesale restructuring of a species, once it has become well established on Earth.
Go to the page to see how examples like this abound. It is my suspicion that McLeroy did not get these quotes himself, but rather got them from another source. It is, however, clear that he didn't do his homework. Read the whole thing. Oh, and by the way, 7B got shot down yesterday.

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