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Springboards, among other things I was checking out Access Research Network ( www.arn.org ) one day at school during lunch, and one of my evolutionist friends came over and saw what was up on my screen. He asked what it was, one thing led to another, and he suggested that I read some books on evolution written by evolutionists, you know, to get their perspective. I basically blew him off, and then said something along the lines of, “I've been indoctrinated from an early age already.” It was a good suggestion, though, and many months later, I decided to pursue it. I went to the library, picked up a copy of Ernst Mayr's What Evolution Is, and am in the process of reading it. I'm glad I did. I'm not even a quarter of the way done with it, but several things jumped out at me. Personally, the fossil record has been a particularly troubling issue for me, in terms of getting over it, and Mayr's brief discussion of the fossil record in the chapter entitled “What is the Evidence for Evolution?” raises some noteworthy points. He states that “the discovery of extinct organisms in older geological strata” is the strongest evidence for evolution. I think most of the evolution-believing public, plus me, would probably agree with him on this. As this section continues, however, Mayr has nearly an entire paragraph that could just as easily be found in any number of creationist or Intelligent Design (ID) books. He says that we would expect “a gradual steady change from ancestral forms to the descendants,” but notes that this is not the case in paleontology. He briefly describes the striking gaps that are found “in just about every phyletic series,” and summarizes the fossil record as “one of discontinuities, seemingly documenting jumps (saltations) from one type…to a different type.” Mayr explains this away, of course, and goes on to cover the “few fossil lineages [that] are remarkably complete,” and in a later chapter states: “Together with molecular sequences, the fossil record, in spite of its many gaps, is the most irrefutable evidence for the occurrence of evolution.” This hardly detracts from our point that the fossil record is very spotty, or in the words of Mayr himself, “woefully inadequate.” Mayr isn't the only scientist to say this about the fossil record, of course. Robert L. Carroll, Curator of Vertebrate Paleontology at Redpath Museum, wrote in 2000: “What is missing are the many intermediate forms hypothesized by Darwin, and the continual divergence of major lineages into the morphospace between distinct adaptive types.” This won't come as a surprise to anyone experienced in these debates, of course, but my instinct tells me it would be news to much of the general public. Besides, without a mechanism, what good are the fossils? Random mutations don't cut it. Until evolutionists can demonstrate a mechanism, I don't see any reason why we should assume they'll even find one. At this stage in the game, common ancestry is just as likely (I would actually argue less likely, but that takes us out of the realm of science) as spontaneous generation. But back to the book. Mayr's treatment of embryology is far less impressive. A caption for some drawings of embryos in his book reads in part, “The earlier the stage of development the more similar are the embryos of the different groups.” In other words, he regurgitates the same line on embryology we hear again and again. Unfortunately for him, it's just not true. The true evidence has been documented time after time, and yet this dogmatic statement continues to surface. Michael K. Richardson and his colleagues revealed in 1996 what embryology actually shows, although they weren't first and were by no means alone. They reported that at the earliest stages of development, embryos from a variety of different organisms are remarkably different. This clashes with Mayr's statement that they were more similar at earlier stages. The ID movement has jumped on the Richardson paper, of course, for at least a couple discernible reasons. First, it had long been held that at the earliest stages embryos were quite similar, and that this was evidence in favor of evolution. This paper proved beyond a doubt that this was not true (despite the fact that people knowledgeable in this field had known this for quite some time). Jonathan Wells explains this in his book, Icons of Evolution. So much has been written about Icons that you, the reader, should be able to get a pretty good idea just from Internet articles. Second, this early developmental variation poses a problem for evolutionists. How would such variations have arisen? Paul Nelson and Jonathan Wells raised this point in early 2002. Such differences “suggest that early development evolves relatively easily,” they wrote, but noted that “[we do not] see heritable variation in early development.” Darwinists are faced with their insurmountable obstacle: mechanism. As I was reading through Mayr's book, the drawings the caption addresses jumped out at me. These drawings are, you guessed it, Ernst Haeckel's! In his book, Wells explains in some detail that these drawings are inaccurate. He notes that “the stage Haeckel labeled the ‘first' is actually midway through development; the similarities he exaggerated are preceded by striking differences in earlier stages of development,” and later describes how Haeckel doctored his drawings. I have to wonder how these drawings wound up in Mayr's book. In the chapter immediately following the one on evidence for evolution, Mayr states that multiple origins of life are indeed possible, but that these “other forms have since become extinct.” He claims, “Life as it now exists on Earth…was obviously derived from a single origin. This is indicated by the genetic code, which is the same for all organisms, including the simplest ones, as well as by many aspects of cells, including the microbial cells.” I have several bones to pick with this statement. First, it is well established that origin-of-life researchers have failed to show how life arose by purely natural means (or, as far as I know, even unnatural means). It is practically impossible. Some people more versed in the literature than I am could argue the specific probabilities, but the basic question to ask, in my opinion, is this: “Have you done it?” The answer, of course, is a flat “No” followed quickly by a “but.” End it there. Forget the “but.” Creating a few amino acids using a mixture of gases that might or might not be the same mixture that was available at the origin of life is incredibly far from showing how life arose (1). If it's so easy, surely it would've been done already. If scientists can't show how life arose once, imagine how unlikely it is that life arose many times. Second, many scientists are openly questioning this monophyletic “tree of life.” Apparently confusing results from molecular phylogenetic analysis have led some, like W. Ford Doolittle, to conclude that the best explanation is that “the pattern of evolution is not as linear and treelike as Darwin imagined it.” So instead of a single tree, we're left with a jungle-like maze. Malcolm Gordon wrote in 1999: “At the macro-scale life appears to have had many origins.” He describes the “base of the universal tree of life” as “a network of inextricably intertwined multiple branches deriving from many…genetic sources.” In other words, rather than a monophyletic tree, many scientists subscribe to a polyphyletic interpretation. Third, the genetic code is not “the same for all organisms,” despite Mayr's claim to the contrary. Surprised? I know I was the first time I read about it. This is one of the classic debates, and one most surely to go nowhere. The evolutionist will say something along the lines of, “The universal code is proof of evolution because it means that everything inherited the common code through common ancestry.” The opposing ID theorist will respond by saying, “No, no, no, you're wrong. The universal code means that the designer simply used the same language to design the various forms of life.” Both positions have merit. A universal code is completely compatible with evolution (i.e., common ancestry). Likewise, a universal code is completely compatible with ID; after all, no one I know of creates a new alphabet every time he or she (or it?) writes something. But this very debate is fundamentally flawed because the code is not universal. (Ignore the upcoming sarcasm. It's self-amusing, good-natured humor, I assure you). Every living thing is made up of cells, except for unicellular organisms, which are made up of one cell (hence the uni- prefix). Each cell, ignoring prokaryotic cells (hang in there, we're almost there), contains a nucleus. Within this nucleus, there are chromosomes (yes, the X and Y thing). These chromosomes are partly made up of genes. These genes consist of DNA sequences. The Hollywood short version of the rest of the story is that DNA strands lead to complementary RNA strands (specific base-pairing is at work here), RNA sequences to specific amino acids, and amino acids to proteins (proteins being extremely important, hence the importance of genes). However, what scientists have actually discovered is not so picturesque (in other words, Danny DeVito shows us the real L.A.). The same RNA sequence (arranged in triplets called codons) in one organism can specify an entirely different amino acid in another. These variations often involve “stop codons,” which signify the end of an amino acid chain. The problem for evolutionists is that the genetic code can no longer be hailed as “universal.” I first read about this in the Discovery Institute's response to the PBS Evolution series. It was mentioned in their guide, but also addressed specifically in two press releases. The first press release featured quotes from Michael Behe, Jonathan Wells, and Stephen C. Meyer. (2) It explained that viewers of the Evolution program would be told that the universality of the genetic code was strong evidence for common ancestry. According to the press release, the code had been thought to be universal, but that scientific evidence accumulated over the last twenty or so years had proven that the code was, in fact, not universal. Variations of the code had been found in numerous organisms and mitochondria. Their second press release, a rebuttal to the response made by the National Center for Science Education (NCSE), went into detail and cited several paper. (3) Without getting into the various issues of this particular “press release war” between the Discovery Institute (DI) and the NCSE, the DI's initial point was true beyond a doubt. (4) The first sentence of Niles Lehman's paper confirms it: “The genetic code is no longer universal, even in non-mitochondrial genomes.” Another 2001 paper, authored by Robin D. Knight, Stephen J. Freeland, and Laura F. Landweber, contains an illuminating diagram that shows the variations of the genetic code. (5) Another paper, of which Landweber and Knight were coauthors, explains that “alternative genetic codes” have been found in both mitochondrial and nuclear genomes, along with several other organisms. There are a number of theories discussed in those papers that could explain these variations, but that's not the point. The point is very simple, actually. The Discovery Institute said the code wasn't universal. They were right. Mayr writes that the code is universal. He is wrong. Period. Ernst Mayr has spent more time studying evolution than I've even been alive. Such a dedicated man certainly deserves my respect. Stephen Jay Gould described him as the “world's greatest living evolutionary biologist and a writer of extraordinary insight and clarity” on the backcover of What Evolution Is. But Mayr is wrong; in fact, he is clearly wrong in two cases (embryos and the genetic code), and is on very shaky ground when he states that life is “obviously” monophyletic in origin, a claim he largely based on his misunderstanding of the non-universal genetic code. If a scientist of Mayr's caliber is making these mistakes (and getting these mistakes published), then it should be no wonder when ID theorists (or even creationists, for that matter) scream that the game is rigged. My friend was right. I should read books on evolution written by evolutionists (one of these days, I'll probably get around to reading The Structure of Evolutionary Theory, but that's going to take some time!). No, not just to point out their recycled errors, but to better understand what exactly I'm arguing against. I've found it's easy to rely on Icons of Evolution and other books and articles written by ID theorists such as Paul Nelson and William Dembski, but I've also realized how much more effective it is in a debate setting to bring up the scientific papers on which their work is based. In addition to strengthening our own convictions not only about the books we read but also about the arguments those books make, we assume the role of reviewer. ID theorists are not perfect, and have made mistakes. There was a great deal of hooblah after Jonathan Wells erred on the Mutant Shrimp Incident, for example, but a correction was made, and that's what counts. (6) If something like this were to occur again, it would be far more helpful to the ID movement if supporters of ID were the ones that caught the mistake. But we also have to be careful not to rely on the citations of our leaders. Quotations can be taken out of context or downright fabricated. Besides, a “Yes” answer to “Have you even read this paper you're citing?!” is better than the alternative if you're involved in a discussion. That is why I have read each of the papers I have cited. I did not fully understand every aspect of them (I'm a mere teenaged layman), but I feel that I have a grasp of the general gist of each. Furthermore, my first trip to the university's library was a great experience, and reading through these papers and trying to understand them served as a springboard for further learning. Just as What Evolution Is served as the springboard for this article. Sources: Carroll, Robert L. “Towards a new evolutionary synthesis,” Trends in Ecology Doolittle, W. Ford. “Uprooting the Tree of Life,” Scientific American, February 2000, pp. 90-95. Gordon, Malcolm S. "The Concept of Monophyly: A Speculative Essay," Biology and Philosophy 14 (1999):331-348. Knight, Robin D., Freeland, Stephen J., and Landweber, Laura F. “Rewiring the Keyboard: Evolvability of the Genetic Code,” Nature Reviews Genetics 2 (2001):49-58. Lozupone, Catherine A., Knight, Robin D., and Landweber, Laura F. "The molecular basis of nuclear genetic code change in ciliates," Current Biology 11 (2001):65-74. Mayr, Ernst. 2001. What Evolution Is. New York: Basic Books. Nelson, Paul A. and Wells, Jonathan. “Searching for Deep Variation in the Model Systems of Evo-Devo,” Progess in Complexity, Information, and Design, 1 (2002). Niles Lehman. "Please release me, genetic code," Current Biology 11 (2001):R63-R66. Richardson, Michael K. et al. “There is no highly conserved stage in the Wells, Jonathan. 2000. Icons of Evolution. Washington, D.C.: Regnery Publishing, Inc. 1. Here I am referring to experiments such as the famous Miller-Urey experiment. Many more experiments than just that one have been performed, of course, but producing a couple amino acids isn't the same as creating a functional protein, much less a cell. 2. "Evolution" Series Charged with "False Claim" on "Universal Genetic Code." http://www.reviewevolution.com/press/pressRelease_FalseClaim.php 3. “Reply To Kenneth Miller On The Genetic Code." http://www.reviewevolution.com/press/pressRelease_ReplyMiller.php 4. The “press release war” I am referring to occurred as a series of exchanges between the NCSE and the DI over the PBS Evolution series. This specific exchange involved the above two press releases, and NCSE's respective responses by Ken Miller (see below). As you can see, NCSE had the last word, but I plan to write up a very belated response to Miller's last.
a) “Miller: A ‘Dying Theory’ Fails Again.” b) “DI Again Fails to ‘Crack’ the Code.” 5. This diagram is provided here by the NCSE: 6. “MUTANT SHRIMP? – A Correction.” http://www.iconsofevolution.com/embedJonsArticles.php3?id=1118 Comments? Contact Tristan Abbey at tabbey@idurc.org. Copyright 2002 idurc.org. All rights reserved. International copyright secured. Click here to return to the Papers Archive
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