Tuesday, July 23, 2013

IDiots Don't Understand Punctuated Equilibria

Intelligent Design Creationism is a movement dedicated to discrediting evolution and attacking the rational explanation of nature.1 The evidence is in the books and blogs and the propaganda distributed to local school boards and state legislators. The attack on science and scientists makes up about 99% of their activities.

Given their dedication to disproving evolution, you'd think that the IDiots must at least understand it. Maybe not all of them—because there are some really, really, stupid IDiots—but certainly some of the most prominent IDiots should know what they're talking about? Right? Doesn't that seem reasonable?

The facts say otherwise. Off hand, I can't think of a single IDiot who has an adequate understanding of the science they attack. Believe me, I've tried harder than most to find an intelligent believer.

The latest example of an IDiot is Raymond (Ray) Bohlin [Encycleopedia of American Loons]. He has a Ph.D. in molecular cell biology from the University of Texas (Dallas). The post is on Evolution News & Views (sic) and it announces The Quiet Passing of Punctuated Equilibrium, Finally!.

Some of you may have forgotten about punctuated equilibria so let me give you a brief lesson. Punctuated equilibria refer to a general observation about the fossil record. In those cases where there's a continuous record for millions of years, the observation is that many species exist for millions of years without substantive change (stasis) then over a short period of time (thousands of years) new species form by cladogenesis (splitting of one species into two).

Most of the examples are small marine species, like trilobites, because those fossil records are extensive and well-documented. The speciation event involves small changes like those between modern species (i.e. different species of fruit flies or different species of pine trees). In fact, most of us wouldn't be able to tell the species apart if we looked at the fossils.

What we're seeing, according to Gould and Eldredge, is normal allopatric speciation in the fossil record. Here's Gould, writing in The Structure of Evolutionary Theory.
The theory asserts no novel claim about modes or mechanisms of speciation; punctuated equilibrium merely takes a standard microevolutionary model and elucidates its expected expression when properly scaled onto geological time. (p. 778)
This is important because many people—including, unfortunately, many scientists—have mistakenly assumed that punctuated equilibria have something to do with large-scale morphological changes (macromutation).

Gould, Eldredge, and others have written extensively about this confusion between punctuated equilibria and saltations. I think most scientists now realize that punctuated equilibria involve normal speciation events. It's correctly described in all the evolutionary biology textbooks.

This brings us to Ray Bohlin and his latest post. Here's what he says ...
From the beginning, punctuated equilibrium was primarily an observation from paleontology that most species seemed to stay the same over millions of years (stasis or equilibrium) and suddenly a new species appeared with no smooth transition (punctuation) from the previous species. Gould, Eldredge, and Stephen Stanley wrote numerous articles and books over twenty years summarizing and applying their ideas to different types of organisms in numerous geological time frames.

This was all fine and good as a paleontological observation, but how was this rapid punctuation supposed to happen biologically? Gould, in particular, was careful to point out that punctuated equilibrium was a descriptive theory of large-scale patterns over geological time, not a theory of genetic process. But if genetic process could not accomplish large-scale patterns, the observation becomes mute.

One of the candidates for explaining rapid change through speciation was some kind of developmental change. At the time it was called a bifurcation. A bifurcation is defined as a series of small changes that suddenly reveals a major shift. A child’s metal cricket or frog is a good example. These toys consist of a short piece of metal, grounded at one end. As the opposite end is bent, it eventually buckles emitting the desired “click.” So perhaps with populations, mutations in a particular adaptation could accumulate over time and suddenly result in a major morphologic shift.
Note the talk of "major morphological shift." It's clear that Ray Bohlin is confused about the speciation events that take place in the fossil record.

You know what's coming next, don't you? Watch for hopeful monsters.
But even in 1984 (when evolutionary developmental biology "evo-devo" was in its infancy) nearly all discussions of developmental gene mutations were discussions of lethal or near lethal changes. As we said in Natural Limits, “Mutations of genes intricately involved in development are what produce hopeless, not hopeful monsters.” In Darwin’s Doubt, following a helpful discussion of punctuated equilibrium along with its many difficulties, Meyer quotes Gould from 2002, “I recognize that we know no mechanisms for the origin of such organismal features other than conventional natural selection at the organismic level” (p. 149).
I bet you were surprised that this creationist post got around to defending Darwin's Doubt! (Not.) What we're seeing is a full court press to promote and defend Stephen Meyer. It's a little embarrassing to watch. I'm actually beginning to feel sorry for them.

You probably weren't surprised that hopeful monsters reared their ugly heads because that's just what you'd expect from IDiots who don't understand what they are talking about. (BTW, I don't know where the Gould quote comes from. Does anyone have a copy of Meyer's book?)2

It doesn't get any better ...
Indeed, in 1993 Gould and Eldredge published a review paper in Nature announcing that punctuated equilibrium had come of age. But towards the end of the paper under the heading of Difficulties and Prospects, they highlight the questions raised by evolutionary biologists. After dismissing a few of those objections, they admit “But continuing unhappiness, justified this time, focuses upon claims that speciation causes significant morphological change, for no validation of such a position has emerged.”
The question posed by Gould & Eldredge refers to an explanation of the coupling between speciation events (cladogenesis) and morhological change in the fossil record. Why do the, often minor, morphological changes associated with new species arise suddenly during cladogenesis rather than gradually as one species transforms into another?

They offer an explanation in the very next paragraph of the 1993 paper and it's the same explanation that Gould prefers ten years later in The Structure of Evolutionary Theory. Here's what they said in 1993 ...
We believe that the solution to this dilemma may be provided in a brilliant but neglected suggestion of Futuyma. He holds that morphological change may accumulate anywhere along the geological trajectory of a species. But unless that change be "locked up" by acquisition of reproductive isolation (that is, speciation), it cannot persist or accumulate and must be washed out during the complexity of interdigitation through time among varying populations of a species. Thus, species are not special because their origin permits a unique moment for instigating change, but because they provide the only mechanism for protecting change. Futuyma writes: "In the absence of reproductive isolation, differentiation is broken down by recombination. Given reproductive isolation, however, a species can retain its distinctive complex of characters as its spatial distribution changes along with that of its habitat or niche. . . Although speciation does not accelerate evolution within populations, it provides morphological changes with enough permanence to be registered in the fossil record. Thus, it is plausible to expect many evolutionary changes in the fossil record to be associated with speciation."
That sounds quite reasonable to me. I wonder why Ray Bohlin didn't mention it? Gould devotes five pages (798-802) to it in The Structure of Evolutionary Theory. It's inconceivable that Ray Bohlin didn't study that big book before posing as an expert on punctuated equilibria, isn't it?

Ray Bohlin continues ....
As Meyer spells out, Eldredge and Gould postulated that the speciation event itself was involved in bringing about abrupt morphological change. But as Meyer makes clear, there was no biology behind the claim, just an observation of the fossil record. Using development as the location of such change has proven extremely difficult, as Meyer also points out, especially when discussing the origin of the major body plans that appear in the Cambrian explosion. Body plans are set early in development and mutations in these early processes are universally disadvantageous.
Puntuated equilibria have nothing to do with the Cambrian explosion. Conflating the two is the mark of .... an idiot.
Punk Eek was dead over twenty years ago but persisted on the coattails of Stephen Gould’s considerable and deserved celebrity. But with him gone, his and Elderdege’s unique contribution to evolutionary theory is finally passing quietly away.
Now do you know why we call them IDiots?


1. It's a part of a bigger war between rationalism and superstition.

2. UPDATE A reader, Paul C. Anagnostopoulos, supplied the reference. It's on page 710. Here's the complete quote from Gould in context. It's part of a discussion about the possibility of species selection.
Several Darwinian strict constructionists, Richard Dawkins and Daniel Dennett in particular, hold that almost everything of interest in evolutionary biology either inheres in, or flows form, natural selection's power to craft the intricate and excellent design of organisms—"organized adaptive complexity," in Dawkins's favorite phrase. ... I do not deny the wonder, or the powerful importance, or organized adaptive complexity. I recognize that we know no mechanism for the origin of such organismal features other than conventional natural selection at the organismal level—for the sheer intricacy and elaboration of good biomechanical design surely preclude either random production, or incidental origin as a side consequence of active processes at other levels. But I decry the parochialism of basking so strongly in the wonder of organismal complexity that nothing else in evolution seems to matter. Yet many Darwinian adaptationists adopt this narrow and celebratory stance in holding, for example, that neutrality may reign at the nucleotide level, but still be "insignificant" for evolution because such changes impose no immediate effects upon organismal phenotypes; or that species selection can regulate longstanding and extensive trends in single characters, but still maintains no "importance in evolution because such a process can't construct an intricate organismal phenotype or numerous, developmentally correlated traits.

Gould, S.J. and Eldredge, N. (1993) Punctuated equilibrium comes of age. Nature 366:223-227. [Text]

Gould, S.J. (2002) The Structure of Evolutionary Theory. Harvard University Press.

48 comments :

  1. The question posed by Gould & Eldredge refers to an explanation of the coupling between speciation events (cladogenesis) and morhological change in the fossil record. Why do the, often minor, morphological changes associated with new species arise suddenly during cladogenesis rather than gradually as one species transforms into another?

    Go back a step. Who says they do? (We have of course argued about this before.) But most of the evidence for PE involves detecting speciation by observing a morphological change. So it should come as no surprise that speciation and morphological change are found to be correlated. Speciation just isn't something paleontology is good at studying. Now, stasis, there's something fossils can tell us about. Punctuation too, though to a lesser extent. Tying either of those to speciation or lack thereof, not so much.

    OK, go back to your main point: IDiots will be idiots.

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  2. So this guy thinks he's the guy to declare what's "passing away" or not in evolutionary biology?

    I haven't read his post, but I dare predict he didn't do a comprehensive review of recent litterature by evolutionary biologists and paleontologists in order to arrive at his conclusion.

    So this is just a minor version of the larger and older "darwinism is dying, evolution will soon be rejected by everyone" -imminent demise of evolution creationist fantasy.

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    1. Yes, the "Imminent Death of Evolution" trope that creationists have flogged for at least 120 years. The language never changes.

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  3. IDiot writes: "This was all fine and good as a paleontological observation, but how was this rapid punctuation supposed to happen biologically? Gould, in particular, was careful to point out that punctuated equilibrium was a descriptive theory of large-scale patterns over geological time, not a theory of genetic process."

    Uh, in the first Gould and Eldredge paper on Punc Eq, they said the pattern was predicted by population genetics.

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    1. Computer simulations of evolution also, curiously, reproduce the PE effect(long periods of statis punctuated with sudden bursty transitions in morphology that coincide with "speciation events") without this ever having been "designed into the programming"(as some paranoid ID nut might assume).

      For a good simple example of this, see:
      Evolution is a blind watchmater
      http://www.youtube.com/watch?v=mcAq9bmCeR0

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    2. That's an interesting video, and the simulation does recover some of the features of evolution. But it has exactly zero to do with PE. You in fact have a simulation of punctuated anagenesis, in which one population changes over time, just not at a constant rate. Nothing to see here. PE, if it's anything, is a theory about the relationship between morphological evolution and speciation (defined as the evolution of reproductive isolation).

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    3. Yes, you're right, it can't be said the video captures speciation, since this would require some kind of simulation of a reproductive barrier between "clock phenotypes".

      I don't think that would be difficult to make though, since you could basically tell the program to disallow matings according to some criterion of how different the descendant population is from the ancestral one.

      Would it then, you think, capture some of the features of PE? If I understand you correctly, that's the main quality separating PA from PE?

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    4. PE is a claim that evolution occurs mostly during speciation, with stasis at other times. I don't think that a simulation would be likely to produce a result like that.

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    5. I think I see what you mean, this sort of simulation is too simplistic to capture that effect. Speculating on the cause of PE, you would need to actually simulate an environment with multiple niches and competing species, and that's a whole different ballgame of course. Would also require much more computer time to simulate.

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    6. John Harshman, to clarify things a bit, will you please state your definitions of evolution and speciation?

      And a question for anyone who would like to respond:

      When it comes to butterflies and moths, would you consider a change in any of the following to be a morphological change:

      1. wing colors/patterns
      2. size
      3. pheromones (sending or receiving)
      4. behavior (especially courtship/mating behavior)
      5. choice of larval host plant (by either the ovipositing adult female or by the larvae after hatching from the eggs)
      6. choice of adult food/nutrient sources (when applicable-not all moths feed as adults)

      ?

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    7. Evolution: Change in the genetic characteristics of populations (and perhaps of biotas).
      Speciation: Evolution of reproductive isolation between populations.

      Technically, only one and two are morphology. Are you going to say that speciation must be accompanied by morphological change of some kind, since isolating mechanisms are morphological features? Nobody ever said that speciation doesn't involve change. The claim of PE is however that most change is associated with speciation, which is quite different.

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    8. Harshman writes: "PE is a claim that evolution occurs mostly during speciation, with stasis at other times. I don't think that a simulation would be likely to produce a result like that."

      As I understand it, there's more to it than that. There are bursts of speciation where a single species branches out into many with different morphological characteristics; then the bush is pruned down by extinction. Large-scale morphological changes are determined by what doesn't go extinct.

      So a (for example) moeritherium will branch out into a dozen species with various lengths of trunk, shorter, longer etc. and a half-dozen species with shorter trunks go extinct, leaving only those with longer trunks, and thereafter skewing the average, and providing permanent morphological change.

      That means the mathematics is dominated by species selection, which is different math than natural selection within a species, a mechanism that Gould deprecated; he appeared to define natural selection as not including species selection.

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    9. Diogenes,

      What you describe there is species selection, not PE. Gould did indeed like species selection, and it may be that PE would make species selection more common and/or likely, but PE is not species selection. On the other hand, Gould thought that speciation happened by ordinary natural selection within populations.

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    10. G&E also explain that part of the reason they even came up with PE was because they wondered what allopatric models of speciation would mean for the fossil record, so the ID claim that it has 'no basis in biology' is insane. This misunderstanding actually suggests that IDers think, 'if it's not a molecular explanation, it's not biology'. Given that, when and if they do have advanced degrees in biology, it's in molecular biology.

      At the same time gould also said that PE was in part developed because he had gone through the effort of learning good statistical methods to detect and analyze anagenesis in the fossil record, and he was frustrated because it didn't seem to occur, he was almost saying 'damnit, I learned this stat BS for nothing!'

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    11. Dio:
      "So a (for example) moeritherium will branch out into a dozen species with various lengths of trunk, shorter, longer etc. and a half-dozen species with shorter trunks go extinct, leaving only those with longer trunks, and thereafter skewing the average, and providing permanent morphological change."

      This was how Gould addressed the issue of getting large-scale morphological change and long term trends in morphology. There had been a criticism of PE that it couldn't explain long term trends, and this species selection is how Gould addressed that criticism (sometimes it seems like Gould felt PE could explain everything, which is a tricky territory for a theory to enter). Gould, of course, felt that there were multiple, valid, influential levels to selection, that evolution has a 'structure'.

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    12. Note that when Gould & Eldredge say "allopatric" they mean "peripatric". Standard allopatric speciation doesn't involve peripheral isolates.

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    13. John,

      Is the distinction between allopatric speciation and peripatric speciation important? Several of the modern evolutionary biology textbooks don't even mention peripatric. In Structure, Gould talks almost exclusively about allopatry and allopatric speciation even though he has a description of Mary's original version of peripatric speciation suggesting that he knows what it meant.

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    14. Mary? Yes, I think the distinction matters. Peripatric speciation is a special case, and PE assumes it's the dominant one. If allopatric speciation is not generally highly asymmetrical, many of the predictions of PE for the fossil record disappear. Transitional populations become less rare, because they aren't small, transient, and at the edge of a range. (I think the poor sampling of the fossil record still accounts for much, but Mayr's explanation goes away.) And the whole "genetic revolution" thing, and any explanation for stasis connected with it, also disappear.

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  4. This idea by Futuyma that links morphological change to speciation; isn't this just the change in allele frequencies associated with the founder effect, applied to developmental genes?

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    1. No, I don't think it is. It's a more general claim; it applies to all manner of genes, not just developmental ones, and to any sort of speciation (or population division), not just founder effect speciation. But is it true?

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    2. It seems to me part of the problem with understanding PE, and I mean no disrespect to Gould and Eldredge here, is that the idea just seems so friggin' obvious. It's often presented as this radical and controversial idea, but from my layperson's perspective it's hard to see why that would be. So I think there are people who misperceive it to be more radically different from the previous paradigm than it actually is.

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    3. Could you briefly describe what you think PE is, and why it should be obvious? I for one think there's no good evidence for it, and it's probably false. The original idea of PE was a description of what we might expect to see in the fossil record if Ernst Mayr's rather odd ideas about speciation were true. You can get an obvious truth out of PE if you remove its central idea (evolution happens during speciation), and adulterate it to the notion that evolution doesn't proceed at a constant rate.

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  5. the observation becomes mute

    Nice English there, Doctor Ray! Lemme guess, all the English composition courses were at UT Austin?

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  6. "The history of life is more adequately represented by a picture of 'homeostatic equilbria' . . . The history of evolution is . . . a story of homeostatic equilibria."

    "The answer [to punctuated equilibria] probably lies in a view of species and individuals as homeostatic systems -- as amazingly well-buffered to resist change and maintain stability in the face of disturbing influences."

    "In this view, the importance of peripheral isolates lies in their small size and the alien environment beyond the species border that they inhabit -- for only here are selective presures stong enough and the inertia of large numbers sufficiently reduced to produce the 'genetic revolution'."
    [Quotes from Eldredge's and Gould's original (1972) article proposing punctuated equilbria.]

    Gould was wrong, of course, about Darwinists being what he mockingly called gradualists, people who assumed evolution to occur at a constant rate. [It is ironic that today the main proponents of ‘gradualism’ are molecular biologists!] This is clear from Darwin's only illustration in the Origin of Species (1859) showing that immediately after speciation morphological divergence first occurs rapidly but later slows as the new species carve out niches in the "economy of nature."

    Darwin recognized divergence and stasis; however, the new, original and bizarre contribution of Eldredge and Gould was their hypothesis that biochemistry, in the form of the now discarded theory of 'genetic revolutions,' made populations refractory to selection. For them biological evolution largely occurred as a result of the pathology of disrupted homeostasis produced by genetic drift in peripheral isolated populations. It is hard to decide whether Gould (as pusher of this appealing, at least to classifiers, essentialist idea of 'natural species') or Bohlin (as an IDiot) deserves more criticism.

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  7. Ray Bohlin should take more credit, his 1984 book "The Natural Limits of Biological Change" is one of the most important ancestors of ID. I believe Bohlin is an OEC and his coauthor was a YEC, which is just about perfect for understanding the origin of ID.

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    1. Indeed, it even uses the phrase "Intelligent design" (or a cognate, I don't have the book in front of me at the moment). Goes to show that the "ID" allele was already in the population, waiting for the selective advantage it was about to receive complements of the supreme court...

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  8. This YEC always understood PE being a retreat that was forced as it became evident there was not the gradual changes in creatures by way of fossil sequences.
    So they HAD to say there was statis and then a jump.
    In all this thee was no biological investigation.
    It was indeed just drawing biological conclusions from biological data points in assumed deposition events of some creature in question.
    There was no biology done.
    Just observation of fossils. The geology did all the thinking.
    Finding a complete lack of gradualism was no longer to be ignored.
    PE pressed hom,e this fact and tried another tactic.
    The fossil record only recorded when creatures were in a steady easy mode of life. It didn't record the changing.
    In reality these fossils just record segregated colonies of the same creatures just as found in the rich amazon today.
    They were all fossilized together leading to a error of interpretation.
    Geology and fossils once again is wrongly claiming to be biological investigation wusing the scientific method.
    Evolutionism is not based on biology.

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    1. Robert,

      I want to thank you for providing comic relief on Sandwalk. However, some of your ridiculous satires of creationist beliefs are getting very close to what they actually believe. Please be more careful in the future or else some readers might think you actually subscribe to those crazy ideas.

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    2. RB:"This YEC always understood PE being a retreat that was forced as it became evident there was not the gradual changes in creatures by way of fossil sequences.
      So they HAD to say there was statis and then a jump."

      This is a perfect example of why you can't put your conclusions in front of your investigation. Creationists have an ideology, they 'know' it is true, and therefore everything has to be in accord with that. So it's not /merely/ that Gould or other biologists are wrong, it's that they know they're wrong and they're making up lies to try to explain that away.

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    3. Re Larry Moran

      Some of the folks over at Panda's Thumb who are familiar with Booby's contributions over there have concluded that he really does believe what he writes.

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  9. "Darwin recognized divergence and stasis; however, the new, original and bizarre contribution of Eldredge and Gould was their hypothesis that biochemistry, in the form of the now discarded theory of 'genetic revolutions,' made populations refractory to selection. For them biological evolution largely occurred as a result of the pathology of disrupted homeostasis produced by genetic drift in peripheral isolated populations. It is hard to decide whether Gould (as pusher of this appealing, at least to classifiers, essentialist idea of 'natural species') or Bohlin (as an IDiot) deserves more criticism."

    Whatever one thinks of the genetic revolutions idea, it doesn't come from Gould, it comes from Ernst Mayr. "Revolutions" was too dramatic a term for it, it just meant recombination and reshuffling of originally co-adapted alleles, and the idea that this would be easier in a small population on the margins of its range than in a large population in the middle of its well-adapted niche.

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    1. Yeah I don't know what the biochemistry bit is about. Mayr of the 1950s was using the then-fairly-vague ideas about genes, reaction norms, etc.

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    2. The way gene products interact and produce phenotypes is largely down to biochemistry.

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    3. I had to be biochemistry 'cause we all know what Mayr thought of genetics. Here's his statement equating population genetics with "beanbag genetics." You can read the history at William Provine: Genetics and Speciation.

      The emphasis in early population genetics was on the frequency of genes and on the control of this frequency by mutation, selection, and random events. Each gene was essentially treated as an independent unit favored or discriminated against by various causal factors. In order to permit mathematical treatment, numerous simplifying assumptions had to be made, such as that of an absolute selective value to a given gene. The great contribution of this period was that it restored the prestige of natural selection, which had been rather low among the geneticists active in the early decades of the century, and that it prepared the ground for treatment of quantitative characters. Yet this period was one of gross simplification. Evolutionary change was essentially presented as an input or output of genes, as in the adding of certain beans to a beanbag and the withdrawing of others (Mayr 1959a, p. 2).

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    4. And yet the idea of "coadapted gene complexes" has nothing to do with biochemistry and everything to do with beanbag genetics, as long as the interactions among beans are important. Mayr had no ideas about the physical nature of those interactions. Simple example: he expected that DNA sequencing would show that morphologically similar species were also genetically similar, to the extent that grades like "reptile" would be apparent in sequence analyses.

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  10. for the FAKE ANGLO-SAXON MONARCHY

    isgodimaginary.com/forum/index.php/topic,54144.0.html

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  11. In my opinion much of ID is creationism in a very shabby cloak, and exists as a Trojan horse. If ID was ever widely accepted they would begin to drop the pretence and move toward full-blown creationism.

    Dave Bailey

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    1. I agree. And even further, once they managed to instill creationist, christian, conservative values everywhere, they'd take the next step and reinstate the inquisition.

      One need only read some of Bill Dembski's mastubatory fantasies about a future where evolutionary biologists are forced to stand trial and defend themselves before the public.

      "I’m waiting for the day when the hearings are not voluntary but involve subpoenas in which evolutionists are deposed at length on their views. On that happy day, I can assure you they won’t come off looking well." - William Dembski

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    2. Hmm, I seem to vaguely recall a hearing or trial or something, in someplace called "Dover", where the issue of evolution vs. intelligent design actually was up for discussion. And several "evolutionists" did show up and expound at length on that issue. I also seem to recall that Dembski declined to do the same, as did almost every other major proponent of ID. The one exception being Michael Behe. And, to put it mildly, he didn't "come off looking well."

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    3. Dembski has long fantasized about having scientists hand-cuffed to a radiator in his basement.

      "I’m waiting for the day when the hearings are not voluntary but involve subpoenas in which evolutionists are deposed at length on their views. On that happy day, I can assure you they won’t come off looking well." - William Dembski

      Bondage fantasy.

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    4. Re lutesuite

      When Dumbski found out that Jeffrey Shallit would be called to refute anything he said about information theory, Dumbski chickened out. That was smart on his part, given what happened to the hapless Behe.

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  12. The Gould quote about "know no mechanisms" is on page 710 of "The Structure of Evolutionary Theory."

    ~~ Paul

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    1. Thanks. I added this footnote to the post ...

      -------------------------

      UPDATE A reader, Paul C. Anagnostopoulos, supplied the reference. It's on page 710. Here's the complete quote from Gould in context. It's part of a discussion about the possibility of species selection.

      Several Darwinian strict constructionists, Richard Dawkins and Daniel Dennett in particular, hold that almost everything of interest in evolutionary biology either inheres in, or flows form, natural selection's power to craft the intricate and excellent design of organisms—"organized adaptive complexity," in Dawkins's favorite phrase. ... I do not deny the wonder, or the powerful importance, or organized adaptive complexity. I recognize that we know no mechanism for the origin of such organismal features other than conventional natural selection at the organismal level—for the sheer intricacy and elaboration of good biomechanical design surely preclude either random production, or incidental origin as a side consequence of active processes at other levels. But I decry the parochialism of basking so strongly in the wonder of organismal complexity that nothing else in evolution seems to matter. Yet many Darwinian adaptationists adopt this narrow and celebratory stance in holding, for example, that neutrality may reign at the nucleotide level, but still be "insignificant" for evolution because such changes impose no immediate effects upon organismal phenotypes; or that species selection can regulate longstanding and extensive trends in single characters, but still maintains no "importance in evolution because such a process can't construct an intricate organismal phenotype or numerous, developmentally correlated traits.

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  13. Don't forget that in Lenski's evolution-in-a-flask experiments, the E. coli population evolved in a stepwise manner. Oh wait, I forgot that it didn't make a new "kind" or is it baramin?

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    1. Each of the twelve independent populations in Lenski's experiment evolve in a gradualistic manner as new mutations arise and become fixed in the population. The steps are simply new mutations, although there is some epistasis that makes them more obvious.

      The experiment is very interesting but the populations are under extreme selection of a sort rarely seen in nature. It has nothing to do with punctuated equilibria.

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    2. It has nothing to do with punctuated equilibria, but it sure poses a problem for folks like James Shapiro, who think that microorganisms can decide upon favorable evolutionary paths. Lenski's E. coli must have finished last in their genetics classes!

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    3. Shapiro is a closet ID-proponent. Everyone knows it.

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