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Losing on ancestry, winning on race I finally finished reading Ernst Mayr's What Evolution Is about 2:45 A.M one Sunday morning. I say “finally” because it took an incredibly long time considering it's only about three hundred pages. In my previous article I pointed out some of the errors Mayr puts out in his book, but there are a few other things I'd like to touch upon, as well. I accepted the fact that his chapter on the evidence for evolution fell a couple hundred meters short of the finish line (in the context of this metaphor, I'm debating whether or not to describe his use of Haeckel's embryos as cheating), and that I would have to read his book realizing this. Setting aside all of his references to common ancestry and to the subsequent mechanism that has yet to be demonstrated, What Evolution Is has given me a clearer understanding of natural selection, variation, and even speciation, while its treatment of human origins confirms what I already thought. By observing and participating in a number of informal on-line debates about evolution, I've come to realize that a significant proportion of the Netizens involved have little clue what they're arguing about. Make no mistake, folks, I used to be one of them. Ignorance all the way! Root, root! But seriously now, it was my many defeats on the Internet that brought me to the library to figure out what the heck I was talking about. One of the terms whose meaning I only basically understood was natural selection. Paul Nelson's chapter in Signs of Intelligence helped to explain “that natural selection is simply a directional shift in the trait frequencies of species,” (140, Nelson) while Mayr's book further clarified it. According to What Evolution Is, natural selection only works on the phenotype, “the totality of morphological, physiological, biochemical, and behavioral characteristics of an individual,” (128, Mayr) as opposed to its genotype, the genetic makeup of it. So in other words, evolution requires more than relatively inconsequential genetic mutations; rather, it needs observable changes in order to function as a process. Since natural selection is a “process of elimination,” (Mayr, 117) these observable changes must be qualified as beneficial to that particular individual. So far, however, there is no mechanism that has been sufficiently demonstrated to account for the new, beneficial, morphological structures that common ancestry requires. Microevolutionary mutations are often hailed as the source for the variation required by common descent. From an evolutionary standpoint, mutations are the cause for new variation, but there is another process that is probably greatly overlooked. According to Mayr, genetic recombination “in a population is the major source of the phenotypic variation available for effective natural selection.” (Mayr, 106) So mutation produces the variants, but recombination is responsible for capitalizing on it. Recombination is a complex process involving proteins and is not random like mutations are. Much research remains to be done in this area, of course, but if most of the variation in a population is due to specific cellular mechanisms, then there's plenty of room for a designer. What Evolution Is also covers in quite some detail the origin of a new species, speciation. Mayr is careful to distinguish between phyletic evolution (one species evolving into another species evolving into another, etc.) and speciation, “the production of several new species by a single parental species.” (176, Mayr) This distinction may provide a basis for distinguishing between speciation in terms of common ancestry, which I don't subscribe to, and speciation in general, which doesn't necessarily involve any changes in morphology. Mayr's basic explanations of sympatric and allopatric speciation do not, as far as I can tell, require any adherence to common ancestry. Many design theorists over the years, including me, have been very reluctant to accept speciation. Part of this may be due to the varying definition of “species,” but I really don't know, since I'm pretty new to this debate. A problem for defining species is the difference between sexual and asexual organisms. If a species is strictly defined as an isolated group that can reproduce viable offspring, then I don't have much of a problem with it, although this becomes a tad problematic when dealing with asexual organisms like bacteria. However, I doubt it's anything but rare, and also must point out that such limited speciation, which is heavily reliant on one's definition of species, doesn't do much for the evolutionist cause. (*) “No well-informed person any longer questions the descent of man from primates and more specifically from apes,” Mayr says. (235, Mayr) According to him, the evidence “is simply too overwhelming.” (235, Mayr) He then proceeds to explain the evidence, and due to the lack thereof, his chapter on the evolution of humans is really quite amusing, although that was beyond any doubt not his intent. One of the principle differences between us Homo sapiens and other hominids and apes is our large brain size. Somehow evolutionists have to explain how brain size increased while the birth canal did not. Mayr's explanation is that “much of the growth of the brain had to be shifted to the postnatal period” (Mayr, 248) and that infants were born prematurely. One wonders what the mechanism for such dramatic changes (our ancestral mothers would also have to change to accommodate the modifications in the infants) was, but like with so many other evolutionary explanations, it just had to happen seems to be the basis. Furthermore, Mayr notes before he traces the history of man to ape: “Any new find may drastically change the situation…It is important in this bewildering situation not to take anything for granted…The resulting picture is entirely based on inferences and any part of it may be refuted at any time.” (Mayr, 239-40) This really isn't too different from Icons of Evolution, in which Jonathan Wells states “we are simply fed the latest version of somebody's theory, without being told that paleoanthropologists themselves cannot agree over it.” (Wells, 225) How interesting. If the evidence is so powerful, how come the theories can be “refuted at any time?” We recently saw an example of how volatile the study of human origins is. Just take a look at the latest issue of National Geographic. If we're not supposed “to take anything for granted,” then how can any well-informed person not question the descent of man from primates? Now, pursuant to the title of this article, I should explain how Mayr “wins on race.” One major theme of What Evolution Is is nailing in a population mindset, as opposed to a typological. One of the most contentious issues in America is race. Somehow we have to reconcile our belief in equality with our obvious differences, which “we must honestly face and admit.” (262, Mayr) Mayr does this well, in my opinion, by describing humanity as a population, not as distinct types or races. According to him, “by rejecting the typological approach, which considers the members of each race as a type, and replacing it by the populational approach in which each individual is considered on the basis of his or her particular abilities, a truer understanding of reality can be achieved that avoids any typological ranking and any discrimination on such ranking.” (262-3, Mayr) This is worth the whole book, and I think Mayr's explanation of race is excellent. As supporters of ID, we should take careful note of his message before we accuse evolution of being a racist ideology. Finally, one passage stood out from the rest in its ambiguity. Mayr states that evolution is a fact, but notes “there are particular evolutionary theories such as those of common descent, origin of life…but scientific arguments about conflicting theories concerning these topics do not in any way affect the basic conclusion that evolution as such is a fact.” (264, Mayr) I've read this sentence and the surrounding ones over and over again. Is there room for a theory of the origin of life that involves an intelligent designer? Is this what Mayr means? Perhaps, but probably not, judging from the rest of his book. Does Mayr mean that common descent is just a theory? If so, then some biology teachers may need a refresher course taught by what Stephen Jay Gould called “[the] world's greatest living evolutionary biologist,” Ernst Mayr, because from what I've seen, it's taught as fact. I doubt that's what he means, though, but what else could he mean? I honestly have no idea. Sources: Mayr, Ernst. 2001. What Evolution Is. New York: Basic Books. *Note: I understand that speciation has never been observed, but there are several websites that I plan to review in the coming weeks. These include the Talk.Origins Archive's “Observed Instances of Speciation FAQ” (http://www.talkorigins.org/pdf/faq-speciation.pdf) and “Some More Observed Speciation Events” (www.talkorigins.org/faqs/speciation.html). It's important to note that even though speciation may never have been observed, from a design standpoint we shouldn't necessarily rule it out as impossible. On the other hand, we shouldn't assume it occurs either. 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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