Admissions of Ignorance in Evolutionary Theory

first_imgFor a scientific idea some have proclaimed as a fact no longer in need of proof, and as well-established as gravity, Darwin’s theory of evolution still reveals surprising weaknesses when its defenders speak about the details.  Detecting these weaknesses requires tuning out the media hype, and tuning into scientific papers and pro-evolution journals where evolutionary theory is debated.  Elisabeth Pennisi wrote one such account in Science last week.1  It revealed that the public is getting a very misleading view of evolution – both its operation and the strength of the evidence for it.    It would seem obvious that evolution needs a genetic basis.  Darwin attempted to explain it in his day, unsuccessfully.  The neo-Darwinian synthesis of the 1930s was supposed to explain it.  Serious questions about how evolution works at the genetic level remain, however, to this day.  This was evident in Pennisi’s use of war metaphors to describe two groups of evolutionists that are “locking horns” over a current issue: whether genes or regulatory elements (in particular, cis regulatory factors) are key to evolutionary change.  The latter, a “fashionable idea,” has been growing in popularity among those in the evo-devo subculture: i.e., evolutionary biologists who focus more on developmental than genetic influences.  When Jerry Coyne and Hopi Hoekstra wrote a pointed critique of the regulatory-element hypothesis in the journal Evolution last year, “Egos were bruised.  Tempers flared.  Journal clubs, coffee breaks at meetings, and blogs are still all abuzz,” she wrote.    None of the combatants doubt Darwin’s theory in the slightest, of course.  Still, some statements in Pennisi’s account could give a Darwin-doubter cause for gloating.  Consider this paragraph:[Sean] Carroll [U of Wisconsin] argued that mutations in cis regions were a way to soft-pedal evolutionary change.  Genes involved in establishing body plans and patterns have such a broad reach–affecting a variety of tissues at multiple stages of development–that mutations in their coding regions can be catastrophic.  In contrast, changes in cis elements, several of which typically work in concert to control a particular gene’s activity, are likely to have a much more limited effect.  Each element serves as a docking site for a particular transcription factor, some of which stimulate gene expression and others inhibit it.  This modularity makes possible an infinite number of cis-element combinations that finely tune gene activity in time, space, and degree, and any one sequence change is unlikely to be broadly disruptive.This sounds like damage control.  Is the standard explanation too risky?  Yet critics of the evo-devo alternative argue that every such “fine-tuning” change must be adaptive to persist through natural selection.  Precious few examples, they say, can be found to illustrate a regulatory change related to a morphological change.  One regulatory change in a mouse, for instance, can make its digits grow slightly longer (see 01/18/2008), but the mutant mouse is hardly ready to take off flying like a bat.    “Where’s the beef?” challenged Pennisi, giving the floor to Coyne and Hoekstra, who countered that mutations for evolutionary change must occur in genes:But Hoekstra and Coyne say this enthusiasm doesn’t rest on solid evidence.  In their Evolution article, they picked apart these examples and the rationale behind them.  They pulled quotes from Carroll’s work to criticize his fervor and berated the evo-devo community for charging full speed ahead with the cis-regulatory hypothesis.  “Evo devo’s enthusiasm for cis-regulatory changes is unfounded and premature,” they wrote.  Changes in gene regulation are important, says Hoekstra, but they are not necessarily caused by mutations in cis elements.  “They do not have one case where it’s really nailed down,” she says.Those be fightin’ words, indeed.  Coyne even used psychological warfare, telling Science, “I’m distressed that Sean Carroll is preaching to the general public that we know how evolution works based on such thin evidence.”    The opposition did not take this sitting down.  “Almost as soon as their article appeared, lines were drawn and rebuttals planned,” Pennisi reported like a war correspondent.  But did they come back with a knock-down case for evolution?  All Sean Carroll could reply was that his view is the best of a bad lot:“I am not trying to say that regulatory sequence is the most important thing in evolution,” he told Science.  But when it comes to what’s known about the genetic underpinnings of morphological evolution, “it’s a shutout” in favor of cis elements, he asserts.That one statement could come as a shock to students who have been taught all their lives that evolution by natural selection acting on genetic mutations is well understood.  The article degenerated from here into the battle of the T-shirts and other fluff.  Coyne, for instance, sported a T-shirt that said “I’m no CISsy,” and entitled his talk at a recent conference, “Give me just one cis-regulatory mutation and I’ll shut up.”    Pennisi reported statistics from pro-evo-devo people purporting to show the extent of regulatory elements involved in mutated genes.  “Yet even these data are inconclusive,” another was quoted admitting.  At the end of the article, there was no winner.  Pennisi’s closing theme, with variations, was how little is known.  Everyone was making excuses.  Evo-devo devotees complained that associations between regulatory elements and morphological effects are hard to measure.  “I really want to emphasize,” Carroll bluffed, “that evo-devo [researchers] haven’t come to this way of thinking simply through storytelling” but through data.  Was this a response to ridicule he has heard?  Or was it a backhanded charge that his opponents are the storytellers?  Either way, it’s hard to feel his conclusions are compelling when the relevance of certain regulatory elements, and their interactions, are confusing, and “the numbers may be misleading.”  How much more so when genetic mutations can affect the regulatory elements themselves?  What role do RNA elements play?  What about gene duplications?  Patricia Wittkop (U of Michigan) suggested there may be more noise than signal when she said, “The important question is about finding out whether there are principles that will allow us to predict the most likely paths of change for a specific trait or situation.”  It would seem any scientific claim needs such principles to be deemed scientific.    If the evolutionists cannot resolve their conflict, they can at least improve their battlefield protocols.  Pennisi ended with this:With so much unknown, “we don’t want to spend our time bickering,” says [Gregory] Wray [Duke U].  He and others worry that Hoekstra, Coyne, and Carroll have taken too hard a line and backed themselves into opposite corners.  Coyne doesn’t seem to mind the fuss, but Hoekstra is more circumspect about their Evolution paper.  “I stand by the science absolutely,” she says.  “But if I did it over again, I would probably tone down the language.”1.  Elisabeth Pennisi, “Evolutionary Biology: Deciphering the Genetics of Evolution,” Science, 8 August 2008: Vol. 321. no. 5890, pp. 760-763, DOI: 10.1126/science.321.5890.760.The vast majority of the public, including high school students, never sees the bickering between Darwiniacs over the most fundamental aspects of their theory.  That’s why you need to see it exposed here.    The lesson in this story is that almost nothing is understood in their tale at a scientific level.  Evolutionists want us to believe that humans have bacteria ancestors.  All the amazing structures in all of life had to emerge from a simple, primordial cell by some undirected biological process at the genetic level.  When it comes to positive evidence for such a fantastic, astonishing claim, the paltry best these true believers could exhibit were inconclusive effects of mutations or regulatory elements on existing complex species: reversible changes to the amount of armor on stickleback fish, bristles or the lack of them on fruit flies (with no idea whether they provide any adaptive advantage), slightly longer digits on mice, and other trivia.  When it comes to negative evidence, look at how both sides falsified each other.  The charges and counter-charges were hilarious.  They go like this:“You have no evidence.”“Oh yeah?  Well, we have a lot more than you!”This is like the Dumb and Dumber T-shirts you see friends wearing at amusement parks.  We’ve taken off the Darwiniacs’ white lab coats and shown you their T-shirts: not just Dumb and Dumber, but Fussy and Fussier, and Deceived and Deceiver.  Should such people be “preaching to the general public” that “they know how evolution works, based on such thin evidence”?  Look under the T-shirt and you see just a skeleton with no scientific fitness.  “Where’s the beef?” indeed.  These Popeyes (05/31/2005) will find no salvation in spinach (01/24/2005).  Their ID nemesis, already fit to the hilt, has already eaten it all.  Skinny lightweights only win in the cartoons.(Visited 76 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

The Extrapolation Fallacy in Evolutionary Storytelling

first_imgThe assumption of universal common ancestry can lead to absurd scientific reasoning.Humans have culture. Insects show cooperative behavior. Therefore, human culture evolved from insect behavior. Does that make sense? Can any scientist really compare those two things, and derive one from the other? They do it, but that doesn’t make it rational. Extrapolation is a logical fallacy, and so is the non-sequitur.Animal Behaviour: Conformity and the Beginnings of Culture in an Insect (Current Biology). After making excuses for studying the “evolution of culture” in fruit flies, (e.g., “it might be misguided to suspect that the learning mechanisms that support culture are inherently complex or difficult to evolve, or that these might exist only in our closest relatives“), these authors make some absurd statements that could never be proved. Here’s an example:Female flies, like many adolescent humans, seem to acquire their partner preferences from the majority choices that can be observed around them.Well, then, the writing of scientific papers was a behavior derived from fruit flies. The authors have to work themselves out of a trap, though. There’s no basis in animal evolution for things we do that should have been easy for natural selection to invent. Here comes a whopper of a just-so story:Why, then, are animal cultures not more common in the wild, especially the cumulative variety seen in humans, where new innovations build on previous ones? Why don’t flies build vehicles to travel over land, why do bees not construct walls around their territory to keep competitors away from their flower patches? The conventional way of answering such questions is that they do not have the required brain power. Behavioural experimental studies on multiple invertebrates, however, indicate that the basic problem-solving skills required, and the capacity to learn from observation, are present in a number of invertebrates. Many seemingly advanced cognitive capacities have recently been shown to be computationally trivial, and the required neural circuits could certainly be implemented in some of the smallest brains. So, the reason why culture, or cumulative culture, is so rarely seen in nature, might simply be that the conditions that favour its emergence are quite rare. It is easy to see how an animal might benefit, for example to cope with rapid man-made global change, if it were given the benefit of a fully-fledged cumulative culture tomorrow. But one would have to develop a scenario by which the first tiny steps in the direction of such a culture would already be beneficial and maintained in a population — and in such a manner that such variation could not be more beneficially just cemented into genes. A laboratory setting under which culture emerges in a free-flowing experiment (i.e. without significant experimenter intervention) is actually quite hard to conceive for any animal. Even if you gave insects all the tools and parts to build a bicycle, there would be little incentive for them to begin building anything in the right direction. Another potential answer to this question may lie with conformity itself. Conformist biases are a useful way to maintain traditions. However, if these biases are so strong that they result in discrimination against new phenotypes, whether brought about by mutation or individual innovation, such novelty may be discriminated against even if it could be of adaptive benefit. This would prevent the accumulation of improvements characteristic of cumulative culture.Nonetheless, fruit flies are an interesting choice of model for cultural processes due to the feasibility of selection experiments in relatively short time spans, and thus the potential of exploring interactions between cultural and genetic evolution. In addition, the expansive molecular-genetic toolkit that is available in Drosophila should make it possible to explore the neural mechanisms underpinning social learning, as well as the processes mediating evolutionary change under conditions in which certain forms of social learning and culture are selectively advantageous.If you endured that long quote without falling asleep, you saw nothing but extrapolation, assumption, waffling, rationalization, and storytelling (“develop a scenario” they call it). Nothing natural selection cannot handle!Human roars communicate upper-body strength more effectively than do screams or aggressive and distressed speech (PLoS One). Evolutionists were not sufficiently embarrassed last time they told a story about the evolution of screaming (2 July 2018). They did it again. While a scientist might be able to gather data on whether a man with a good roar has good upper-body strength, what does that have to do with the price of natural selection in China?In competitive contests, evolutionary selection processes favour vocal communication of resource holding potential to settle disputes without engaging in potentially costly combat. For example, many terrestrial mammalian species, including giant pandas, sea lions, fallow and red deer, and domestic dogs use acoustic cues to body size or dominance rank in aggressive vocalizations to mediate agonistic interactions, particularly during male-male competition.Among humans, the nonverbal components of speech also allow listeners to assess body size from the voice, including height and weight…How stupid can Darwine-drunk scientists get? Ask Cyrano de Bergerac if he had better success winning his love by roaring or by serenading. To evolutionists, they justify such absurdity because of their belief that humans are mere animals. If dogs howl and sea lions say “Ork! ork!” to each other, then humans must have gained this ability because of the Stuff Happens Law, too. This is the fallacy of extrapolation: thinking that humans are nothing but evolved pandas, and so animal behavior can be extrapolated into human behavior. The illustration above says it all. Roar at a woman, and you are not likely to gain love, regardless of your upper-body strength. You are likely to get charged for harassment.You may now LOL.Evolutionists continue to carry out their silly game of applying natural selection to everything, including human behavior, because nobody feels safe to laugh. That must change. Go ahead: roar at an evolutionist, and explain you are just trying to win their love. Then laugh hilariously. If they get huffy about it, then engage them in a little logic. Tell them, “If human culture is nothing but evolved fruit-fly behavior, then so is the behavior of writing scientific papers. Therefore, everything you say was predetermined in your genes, and signifies nothing.” (Visited 462 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more