The Politically Incorrect Guide to Darwinism and Intelligent Design Free
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FREE THE POLITICALLY INCORRECT GUIDE TO DARWINISM AND INTELLIGENT DESIGN PDF Jonathan Wells | 273 pages | 25 Aug 2006 | Regnery Publishing Inc | 9781596980136 | English | Washington DC, United States The Politically Incorrect Guide to Darwinism and Intelligent Design | Discovery Institute Store This article is part of a series of critiques of Jonathan Wells' The Politically Incorrect Guide to Darwinism and Intelligent Design that will be appearing at the Panda's Thumb over the course of the next week or so. Previously, I'd dissected the summary of chapter 3. This is a longer criticism of the whole of the chapter, which is purportedly a critique of evo-devo. Jonathan Wells is a titular developmental biologist, so you'd expect he'd at least get something right in his chapter on development and evolution in The Politically Incorrect Guide to The Politically Incorrect Guide to Darwinism and Intelligent Design and Intelligent Designbut no: he instead uses his nominal knowledge of a complex field to muddle up the issues and misuse the data to generate a spurious impression of a science that is unaware of basic issues. He ping-pongs back and forth in a remarkably incoherent fashion, but that incoherence is central to his argument: he wants to leave the reader so baffled about the facts of embryology that they'll throw up their hands and decide development is all wrong. Do not be misled. The state of Jonathan Wells' brain is in no way the state of the modern fields of molecular genetics, developmental biology, and evo-devo. Here's my shorter version of Wells' chapter 3, titled "Why you didn't 'evolve' in your mother's womb. The strongest evidence for Darwin's theory was embryology, but Karl Ernst von Baer, who laid out the laws of development, did not think they supported evolution, and Ernst Haeckel twisted and distorted von Baer's laws and faked his data to support Darwinism. He was wrong, and the earliest stages The Politically Incorrect Guide to Darwinism and Intelligent Design vertebrate embryos do not resemble one another at all, so Darwinism was built on a false foundation, and they're The Politically Incorrect Guide to Darwinism and Intelligent Design using Haeckel's faked data in our textbooks. Oh, and mutant fruit flies are still just flies. That's right, it's a rather boring rewrite of a premise of his book, Icons of Evolutionwhich I hammered on over three years ago. He hasn't learned a thing since, and he's making exactly the same arguments. I'll take a different tack this time and expose the sleight of hand he's pulling. Here's the centerpiece of his ploy. It's a basic concept in evo-devo, proposed in the early s by Duboule and Raff as a summary of years worth of observations, called the developmental hourglass. What it illustrates is that we have great diversity in the earliest stages of development, in the blastula and gastrula and neurula, but that they all converge on a more similar form, the pharyngula, at what's called the phylotypic stage…and then they diverge once again to achieve the diversity of adult forms. This is a great opportunity for a creationist. You see, when you dig into the developmental biology literature, you will find some papers taking about the similarities of embryos at the neck of the hourglass, and you will also find other papers talking in some detail about the great differences before and after that stage. You will also find marvelous possibilities for confusion in the vague and malleable term "early"—to me, for instance, anything before the pharyngula stage is early, and everything after is late and relatively uninteresting. To put that in perspective, though, humans reach that stage at the 4th or 5th week of pregnancy—so I'm basically declaring month two and later of the human pregnancy to be late development. We do tend to throw around the terms early and late as relative measures of the timing of events, but we also name specific stages and processes…the fine details of which Wells leaves out, to make everything that much more confusing. This is the heart of Wells' strategy: pick comments by developmental biologists referring to different stages, which say very different things about the similarity of embryos, and conflate them. It's easy to make it sound like scientists are willfully lying about the state of our knowledge when you can pluck out a statement about the diversity at the gastrula stage, omit the word "gastrula," and pretend it The Politically Incorrect Guide to Darwinism and Intelligent Design to the pharyngula stage. Here's how Wells quotes William Ballard a well known elder developmental biologist, who has done a lot of work on fish and is therefore familiar to me :. It is "only by semantic tricks and subjective selection of evidence," by "bending the facts of nature," that one can argue that the early embryo stages of vertebrates "are more alike than their adults. Always be suspicious when you see partial phrases quoted and strung together by a creationist. Little alarm bells should be going off like mad in your head. This is from a paper in which Ballard is advocating greater appreciation of the morphogenetic diversity of the gastrula stage—that is, a very early event, one that is at the base of that hourglass, where developmental biologists have been saying for years that there is a great deal of phylogenetic diversity. Here's what Ballard actually said:. Before the pharyngula stage we can only say that the embryos of different species within a single taxonomic class are more alike than their parents. Only by semantic tricks and subjective selection of evidence can we claim that "gastrulas" of shark, salmon, frog, and bird are more alike than their adults. See what I mean? He has lifted a quote from a famous scientist that applies to the gastrula stage, stripped out the specific referents, and made it sound as if it applies to the pharyngula stage. It's a simple game, one he repeats over and over in this chapter. One might argue that maybe Ballard also thought these semantic tricks applied to the pharyngula stage, and so Wells was representing his general views accurately. Alas, this cannot be. The paragraph before his mangled quote says this, rather plainly:. All then arrive at the pharyngula The Politically Incorrect Guide to Darwinism and Intelligent Design, which is remarkably uniform throughout the subphylum, The Politically Incorrect Guide to Darwinism and Intelligent Design of similar organ rudiments similarly arranged though in some respects deformed in respect to habitat and The Politically Incorrect Guide to Darwinism and Intelligent Design supply. After the standardized pharyngula stage, the maturing of the structures of organs and tissues takes place on diverging line, each line characteristic of the class and further diverging into lines characteristic of the orders, families, and so on. It's a classic quote mine. Wells has edited the quote to suit his ends, and has also utterly ignored the sense of the paper, which directly contradicts his claims, to produce a grand lie and tie it to the reputation of a distinguished senior scientist. I could stop here. With that one example, Wells is exposed as a disreputable scoundrel, a sloppy ideologue whose 'scholarship' is untrustworthy and willfully distorted. You simply The Politically Incorrect Guide to Darwinism and Intelligent Design believe one word he says. I will go on a little further, though, and try to explain some of the ideas he has treated so shabbily. There is a fair amount of debate in the evo-devo community about the reality of the developmental hourglass, but Wells doesn't seem to touch on the actual arguments at all—merely these strawman complaints and garbled chronologies that he uses to cast false doubt on the evolutionary process. One serious question is about how wide the waist of the hourglass actually is: an overzealous Haeckelian interpretation would be that it is very narrow indeed, but serious embryology none of which seems to be done by Intelligent Design proponents demonstrates that there is a significant amount of variation within the phylotypic period. Michael Richardson relaunched a critical reevaluation on the basis of morphology, and there have been a number of attempts to analyze the molecular basis of the model several papers are cited at the end of this article; some find no detectable evidence of a consistent molecular pattern, others do. If it does pan out as a universal and coherent property of developing embryos that they should have a conserved stage, the next question is "why? I actually rather like Raff's explanation: that it is a matter of scope. The diagram to the right below outlines this idea. Development is a process of increasing complexity the grey line. The assembly of an integrated body plan requires, at some time, a pattern of global interaction—there has to be information generated at some point to specify where the head will be relative to the tail, etc. The Politically Incorrect Guide to Darwinism and Intelligent Design instance, somites, one of the body elements characteristic of the phylotypic stage, form under the influence of a somitic clock, rhythmic waves of molecular activity that sweep the The Politically Incorrect Guide to Darwinism and Intelligent Design of the trunk and tail. One idea is that these 'whole body' specification events are conserved and are difficult to uncouple from one another, so all the features for which they are responsible tend to appear together in a coordinated fashion…and that coordination is what we call the phylotypic period.