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One of the interesting points to glean from plants and any animal species that are preserved in the fossil record, is their maintenance over time. You can go to a botanical garden today and see a plant called a cycad. You might think of these as something looking like a dwarf palm trees, but that's a close approximation for a description of a remarkably old species. Fossils bearing impressions of cycads of long ago suggest this plant type has changed very little over time. In fact, some features (for example the numbers of stomata or 'pore structures' in the leaf surfaces) can be examined in present day and ancient fossil impressions to reveal something about differences in growing conditions. But over all, the species has changed very little. Stasis is defined as

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PLACE HOLDER - DRAFT ARTICLE

The 3'_5' exonuclease activity plays a critical role in replication: it allows the enzyme to proofread the new DNA and cut out any mistakes it has made. Although the polymerase reads the sequence of the old DNA to produce new DNA, it turns out that simple base paring allows about one mistake per thousand base pairs copied. Proofreading reduces errors to about one in a million base pairs. The question for design theorists is whether proofreading exonuclease had to be present in the very first cell. That is, could the first cell, with its required complement of genes coded for by DNA, have successfully reproduced for a significant number of generations without a proofreading function? Behe (MC) Page 187

 

When the chromosomes duplicate they don't do a perfect job of copying the DNA. They make about one error every 10,000 base pairs they copy [Darnell et al. 1986]. That's the error rate of a typist if he made one error every five pages. That error rate might be good enough for the office, but it's not good enough for genetic transcription. The genetic information has to be copied much more accurately than that to keep the errors from building up over the generations. To reduce the errors, the cell proofreads the DNA and corrects any errors it made in replication. But a few errors remain even after the proofreading. They are known as copying errors, or single-nucleotide substitutions. They are mutations belonging to a class known as point mutations. They are few enough for the species to tolerate. With the proofreading, the copying has a very low error rate from one in a billion to one in a hundred billion. One error per hundred billion would be like one error in a fifty million pages of typescript. Fifty million pages are the lifetime output of about a hundred professional typists. And that's some proofreading! The cell, or organism, can allow this small error.* [* Most evolutionists hold that these errors even play a positive role; they look on these errors as the source of the variation in neo-Darwinian theory needs. I disagree; I think these small errors just represent the limit of the accuracy with which DNA can be copied. Although I concede that they might play a role in small-scale evolution, I hold that they play no positive role in large-scale evolution. As we shall see in the following chapters random variation cannot lead to large-scale evolution.] Spetner (NBC) Page 38

 

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Quotations from "Mere Creation" (MC) edited by William A. Dembski are used by permission of InterVarsity Press, P.O. Box 1400, Downers Grove, IL 60515. www.ivpress.com All rights reserved. No portion of this material may be used without permission from InterVarsity Press.

Quotations from "Not By Chance" (NBC) written by L. Spetner, are used by permission granted by Dr. Lee Spetner.

Writer / Editor: Dr. T. Peterson, Director, WindowView.org
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