Friday, February 12, 2016

This is what a strawman looks like

This is another post about the stupidity of Intelligent Design Creationists. Stop reading if you don't need any more convincing.

Today is Darwin Day. It's the anniversary of the birth of Charles Darwin (Feb. 12, 1809 - April 19, 1882).

This is not a happy day for the Discovery Institute so they've put up a series of posts on Evolution News & Views (sic) to discredit Darwin and "Darwinism."

One of them is by the newly rejuvenated poster boy, Michael Denton: On Darwin Day, Darwinism Is Well Past Its "Sell By" Date. Here's the part I want you to see,
To understand the core weakness of the Darwinian worldview, it is important to understand what Darwinian natural selection requires. The process will work its magic, building up functional structures in organisms, only when two very strict conditions are met: First, the structure must be adaptive—that is, helpful to the organism in flourishing in its environment—and second, there must be a continuum of structures, functional all along the way, leading from an ancestor species to the descendent.

That is, the thing we are trying to explain must in some way help the creature survive, and between the creature and the creature's ancestor there must be a gradual change, each step of which is stable and enhances fitness, or success in reproduction.
Strictly speaking, that's a reasonable explanation of Darwinism as most evolutionary biologists understand it. But here's the problem. There aren't very many evolutionary biologists who are strict Darwinists these days even though there are many who tilt strongly in that direction.

Denton want his followers to believe that this is the standard view of evolution. He knows better. He is deliberately deceiving his followers by setting up a strawman.
Problem number one is that there are a great number of complex structures in nature that are not led up to by known functional pathways, and imagining what these pathways might have been is in most cases very hard. But this challenge is greatly compounded by an additional problem: that in many cases complex structures convey not the slightest evidence that they ever performed an adaptive function in putative ancestral forms. This may come as a surprise to the student of evolution. The trade language of biology has focused on the concepts of adaptation, fitness, and utility for so long that it has in a sense blinded us to the universe of apparently non-adaptive order that permeates the entire organic realm.

For example, what is the adaptive fitness of the shape of a maple leaf? Or the shape of any leaf, for that matter? Nor are examples of seemingly non-adaptive order limited to the shapes of leaves. Some of the best examples are embedded deep within the biological world -- among the characteristics that define and separate the basic kinds or types of plants and animals from each other.
The role of chance and accident in the history of life should be familiar to all students of evolution even if they don't completely adopt such a worldview. They aren't much of a student if the concepts I described in Replaying life's tape aren't well-known to them. They should have read the "Spandrels" paper as undergraduates.

Michael Denton knows about Stephen Jay Gould. He knows about neutral alleles and random genetic drift. I'm sure he's read the "Spandrels" paper and I know for a fact that Denton is familiar with Gould's ideas of contingency and unpredictability because he discusses them in his book Nature's Destiny (1998). Here's a passage from page 296 of that book.
The notion that the transition of life was directed of facilitated by the laws of nature is perfectly consistent with the biocentric model of nature. Indeed, in a biocentric universe, where all the laws of nature have their ultimate meaning in the existence of life, it is hardly conceivable that the origin of life would have been left to chance. From a teleological perspective, the origin of life must be viewed as something quite inevitable and built into the laws of nature from the beginning, just as were the properties of water and the mutual fitness of DNA and protein and all the other coincidences in the physical and chemical properties of life's constituents.

Curiously, many biologists are willing to accept the possibility that the origin of life might be built in but not the subsequent path of evolution. For example, Stephen Jay Gould, in a recent article entitled "War of the World Views" in the journal Natural History, proposes, "that the simplest kind of cellular life arises as a predictable result of organic chemistry and the physics of self-organizing systems but that no predictable directions exist for life's later development." (My emphasis.) But surely it is far more likely that, if the chemical evolution of the first cell was built in, then the far less complex process—the biological evolution of life—will also turn out to be true.
It's inconceivable to me that Denton could discuss Gould's worldview without realizing that he is not the kind of strict Darwinist described in his latest post. He knows that the standard view of biologists is that the history of life is not just the product of natural selection as he makes out to his readers. In fact, Denton even admits this on page 16 of Nature's Destiny when he says, "The prevailing view within the biological sciences is still that life and man are fundamentally contingent phenomena."

His post continues,
Consider the pentadactyl (five-finger) design of the tetrapod limb, witnessed in the human arm and leg: one bone (the humerus in the upper arm, the femur in the upper leg), two bones (the radius and ulna in your lower arm, the tibia and fibula in the lower leg ), five fingers and five toes. This unique design occurs in the fore and hind limbs of all tetrapod (four-limbed) vertebrates, including human beings.

It is clear that in all tetrapod limbs the same basic design has been adapted to very different uses. However, given that the adaptive forms of the fore and hind limbs differ to some degree in every known tetrapod, it is very difficult to explain how the underlying pattern could have been arrived at so as to serve some adaptive end in a hypothetical fore and hind limb of an ancestral tetrapod. The Darwinian explanation, attributing the underlying structure to previous rounds of natural selection, is self-evidently ad hoc.

If we can't explain what specific adaptive function the pentadactyl design serves in any known extant or extinct species of tetrapod, there are no grounds for the Darwinian claim that there was some hypothetical species in some hypothetical environment where this unique design did serve some mysteriously obscure adaptive function in both limbs. In this case, even "just so stories" can't legitimate the Darwinian account.
Denton could not possibly have missed Gould's essay on Eight (or Fewer) Little Piggies since it's a very well-known criticism of the very strawman that Denton is erecting. Allow me to repeat the quotation I posted yesterday to illustrate the conflict. Here's what Gould says in his essay,
Never apologize for an explanation that is "only" contingent and not ordained by invariant laws of nature--for contingent events have made our world and our lives. If you ever feel the slightest pull in that dubious direction, think of poor Heathcliff, who would have been spared so much agony if only he had stayed a few more minutes to eavesdrop upon the conversation of Catherine and Nelly (yes, the book wouldn't have been as good, but consider the poor man's soul). Think of Bill Buckner who would never again let Mookie Wilson's easy grounder go through his legs--if only he could have another chance. Think of the alternative descendants of Ichthyostega, with only four fingers on each hand. Think of arithmetic with base eight, the difficulty of playing triple fugues on the piano, and the conversion of this essay into an illegible Roman tombstone, for how could I separate words withoutathumbtopressthe spacebaronthistypewriter.
How could Denton be so dishonest? He's ignoring one of the most common views in evolutionary biology; namely, that there is NOT an adaptive explanation for five digits. It's an historical accident.

Why would he set up such a strawman version of evolution in his post if he knows better?

Denton continues,
The challenge to the Darwinian framework is not restricted to the tetrapod limb, but applies almost universally to a veritable universe of other novel structures—the insect body plan, the concentric whorl pattern underlying all flowers, and the enucleated red blood cell found in all mammals, which was the subject of my own doctoral work at King's College in London.

Contributing further to the challenge inherent in so much non-adaptive order are revelations from the new field of evolutionary developmental biology (evo-devo). We now know that the paths of evolution have been highly constrained by a set of universally conserved developmental genetic mechanisms that transcend any immediate adaptive utility. Moreover, evo-devo implies that in the case of many novelties, internal constraints have played a decisive role in evolutionary origins.

In my new book, I detail vast quantities of evidence from the most up-to-date scientific literature, all supporting the radical idea that Darwinism played a very minor role in the history of life, and that evolutionary biology in the 21st century will have to seek an entirely new causal framework.
If his new book is all about attacking a strawman version of evolution then why should any of us bother to read it?

Many leading evolutionary biologists have long rejected a strict Darwinian explanation for the history of life. They recognize that modern species are the product of highly contingent pathways that were subject not only to environment influences (mass extinctions) but also to the fixation of neutral and detrimental alleles giving rise to non-adaptive, and even maladaptive, structures.

This is the modern view that refutes Denton's claim of the inevitability of humans or other conscious beings. This is the view that replaying the tape of life will almost certainly result in a different outcome. There is abundant evidence to support such a view. It is non-Darwinian. He must know this. Why is he creating a strawman version of evolution?


67 comments:

  1. ***For example, what is the adaptive fitness of the shape of a maple leaf? ***
    I'm puzzled why, of all the examples he could use, he chose this one. I'm pretty sure I've read about how different leaf shapes are adapted to different temperatures and humidity. I've read of one paleobotanist who has attempted to reconstruct past climates in North America based on the patterns and numbers of different leaf fossils.

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    1. Yes, that's a remarkably ignorant complaint on his part, which pushes his book into the realm of farce. Although Denton could make some hay out of non-adaptive variations in some leaf shapes, asserting that leaf shape in general has no adaptive significance is ridiculous ("For example, what is the adaptive fitness of the shape of a maple leaf? Or the shape of any leaf, for that matter?"). When was the last time he saw a spherical leaf, for example? Leaves that are not needles are primarily thin planes, for obvious functional reasons. Drip tips are beneficial in rainy climates. Needle-like leaves and small leaves with thick cuticles prevent water loss in climates where water stress is a problem, while broad leaves generally catch more sun, which is beneficial as long as they don't permit the loss of too much water. In dense rainforest, leaves low in a dark understory generally need to be large, to catch what little sunlight gets through, while smaller leaves at the top of the canopy have no trouble intercepting enough sunlight. Leaves from the top of the canopy can have more complex edges and lobes, for faster shedding of heat (think oaks versus dogwoods). And on and on.

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  2. Biology is, and Denton must know it is, as thoroughly post-Darwinism as chemistry is post-Daltonism; I blogged about it for this Darwin's day here (if I may): https://paulbraterman.wordpress.com/2016/02/11/even-on-his-birthday-dont-say-darwin-unless-you-mean-it/

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  4. I don't mean to offend you on your religious holiday but on what particular aspects do you agree with your idol, if you will? Can you be specific on the issues you do agree on and the ones you don't
    I think this can be very interesting.

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    1. At this point it doesn't even matter that you're so fucking stupid that you can't tell the difference between darwinism and evolution, even in a post that's largely about it.

      Now let's address the religious part. If Darwin's day is a "religious holiday" and you're asking about what their "followers" disagree with him about, what do you disagree about with Jeebus?

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  5. BTW: I'm a little bit uncomfortable mentioning it that you didn't acknowledge in any of your posts that your buddy Dawkins is recovering from a stroke.

    I just hope that you didn't know about it and that is the reason for your impotence in this regard.....

    Because we ALL wish him well and a speedy recovery!

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  6. For what it's worth, Denton tries to locate the focus of "non-Darwinian" novelties in what he calls "homologs".

    "As I use it, this term refers to a unique biological characteristic or trait shared by all the members of a particular group such as the pentadactyl ground plan of the tetrapod limb shared by all tetrapods. A homolog is therefore a “taxa-defining novelty.” The term homolog is used frequently by researchers in evolutionary developmental biology (evo-devo) to describe such character traits. Systematists often describe homologs as “synapomorphies” or “apomorphies”. In the nineteenth century, Richard Owen termed them “primal patterns.”" (p. 13)

    He eventually goes on to claim that the tetrapod limb results from a series of these homologs.

    “In sum, it is now clear from advances in evo-devo that the tetrapod limb is not just one unitary homolog, but a combination of homologs. The tetrapod limb is built like the animal body from a combination of Owen’s atoms – the phalangeal development homolog or module (PDM), the metapodial homolog (MDM), the digit spacing module (DSM), the digit identity module (DIM), the “pentadactyl developmental homolog”, and so forth. The formula of the limb, following Owen’s atomic conception of the organism as a combination of basic homologs, would be: PDM + MDM + DSM + DIM +… the tetrapod limb is not, then, an individual “primal pattern” in Owen’s terms, but a composite of several “primal patterns”, and each is the result of a highly integrated, novel set of developmental processes.” (p. 165)

    I fully agree that he is knocking the stuffing out of a strawman since he claims that "Darwinism" should have to account for the adaptive advantage of every step in the emergence of these "homologs".

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  7. I just watched a YouTube video the other day-- sorry, I don't remember which one-- in which Neil Shubin pointed out that several different lines of bottom-dwelling fish have developed walking limbs to get around. And their limbs are all completely different from the tetrapod pattern. So there's no necessity for our particular limb pattern. It's just the one that fish who had other features convenient for land-living happened to have.

    (No, I hadn't heard Dawkins had a stroke. Of course I hope he fully recovers. Sending out dumb tweets isn't something that should be punished by death or permanent disability.)

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    1. It could be that I'm missing something but it seems odd that Denton uses the pentadactyl limb as an example of a "homolog" that supposedly is shared by all extant tetrapods. Five digits are found in only some tetrapods. Other groups of tetrapods have two, three, or four digits. For example, artiodactyls and perissodactyls have odd or even numbers of digits respectively. Please correct me if I am misusing these terms.

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    2. Or zero digits, fairly often. Or as many as 8 in the most primitive tetrapods.

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    3. A homology is a trait which two species share due to common descent (i.e. it was a trait present in their MRCA and that's how they got them). Now, Hennig introduced the terms autapomorphy, synautapomorphy (also synapomorphy) and symplesiomorphy (also just plesiomorphy) to make that more precise. An autapomorphy is a derived character state, a synapomorphy is a derived character state shared by some number of species and a plesiomorphy is a primitive character state shared by some number of species. All of them are homologies.
      The pentadactyl limb is a synapomorphy of the crown tetrapoda (while stem line tetrapods had quite a bit of variation in digit number). I.e. all tetrapods that currently exist (as far as we know) shared an ancestor with 5 digits. Of course there are further derived states where the number of digits is changed.

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    4. On digits of ichthyosaurs, from wikipedia: "Sometimes the number of fingers is reduced, to as low as two. This is a rather common phenomenon within the Tetrapoda. Unique, however, for derived tetrapods, is the fact that some species show non-pathological polydactyly, the number of fingers being higher than five. Some species have ten fingers per hand. These fingers again, can have an increased number of phalanges, up to thirty, a phenomenon called hyperphalangy, also known from Plesiosauria, mosasaurs and Cetacea. The high number of elements allows the flipper to be shaped as a hydrofoil... sometimes even an extra lower arm element is present."

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    5. How can Denton explain that with "structuralism"?

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    6. I was hoping Denton could explain why my paternal grandmother had an extra digit on one hand.

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    7. I'm interested in the difference between Denton's "homology" and a synapomorphy. As far as I know, a clade is defined by descent from a common ancestor. Shared derived traits, synapomorphies, are used to help specify clades but they do not define them. Denton thus seems to go off on his own when he characterizes a homolog as a “taxa-defining novelty.”

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    8. Well, a clade is defined in the abstract as an ancestral species and all of its descendants. There are 3 ways to define a particular clade:
      1) phylogenetic bracketing, where you take two species and define a clade as their MRCA + descendants.
      2) as sister to another clade, where you take the sister species of the ancestor af a defined clade and all descendents as the new clade
      3) Through an apomorphy, where you use the species in which an apomorphic character first appeared + all descendents.

      In 3 the clade is defined by an apomorphic character (you could define it through several characters and define the clade through the species where the last of them evolved - we don't always know in which order they did).

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    9. Even in the case of an apomorphy-based species definition, the clade isn't defined by the character. It's defined by the ancestor in which that character first evolved. Snakes are still tetrapods, even though they don't have legs.

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  8. I don't understand how this argumentation would work even against a totally adaptationist paradigm. Surely it is clear that in all these cases we would have a morphospace where very similar positions are equally fit but a massive number of more distant positions are lethal? Imagine a maple tree with cubic 10 x 10 x 10 cm leaves or a mammal with 500 fingers on each limb...

    (And that is also always my thought when faced with this contingency/adaptation issue. Zoom out a bit and consider all the other options and you will find that there is adaptation, at least stabilising selection for the niche of "not being dead". Zoom in into the specifics and you will find a random walk through a space of solutions that are all more or less equally useful.)

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  9. "For example, what is the adaptive fitness of the shape of a maple leaf?"

    Denton makes a good point. Some things exceed normal utility. Having a bladder to accumulate urine is definitely convenient, but it is also extravagant.

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    1. What shape should a maple leaf be to simply achieve normal utility? How would you determine this?

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    2. "What shape should a maple leaf be.."

      Oh, I don't know about 'should' be. From my point of view, there are as many variations as there are intentions. As with bladders, from an evolutionary point of view, nice touches can apparently be selected for.

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    3. there are as many variations as there are intentions.

      So there is no such thing as an unintended variation?

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    4. I suppose there is if you can assign serendipity to random DNA replication errors and natural selection.

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    5. No need to assign, it just is what it is.

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    6. "Having a bladder to accumulate urine is definitely convenient, but it is also extravagant."

      If modern amphibians are anything to go by (which, of course, they may not be), then an orignal function of the bladder was to further resorb water after kidney filtration. Amniotes have more efficient kidneys, so this function is not seen (although I think I recall seeing some evidence of it in lizards). Whatever, many amniotes (most diapsids) have lost the bladder entirely as they excrete a semi-solid paste of uric acid. The retention of the bladder in mammals also serves an important social function ---- most mammals use urine to mark their territory and for other social (or antisocial) functions.

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  10. Larry,

    Denton says that:

    “the thing we are trying to explain must in some way
    -help the creature survive, and
    -between the creature and the creature's ancestor there must be a gradual change,
    -each step of which is stable and
    -enhances fitness, or
    -success in reproduction”

    If indeed “There aren't very many evolutionary biologists who are strict Darwinists these days”, then they must have enlightened views about the things Denton mentions. Which ones?

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    1. Anyone who has been reading this blog as long as you have should be able to answer that question easily, unless they are extremely stupid or willfully ignorant. So which are you, txpiper?

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    2. "Never attribute to malice that which is adequately explained by stupidity."

      But in this case I'm putting my money on malice.

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  11. Like txpiper I don't see the strawman or a strawchild either.
    I understand THIS is the main operation for evolution. Yes other things are now included but does this make Dentons list a tiny minority of evolutionary process??
    Most public teaching on evolution would be Denton's portrayal.
    Why is it not the major point? Is it now a minor point? Or no point?

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  12. The strict Darwinian views the OP attributes to no one are the standard views in popularizations. Nobody ever talks about random genetic drift or other aspects. Recently Jerry Coyne did a two part blog about the selective advantage of the zebra's stripes. Sure he mentioned it but blandly observed he suspected there was an advantage. If suspicion is all it takes to dismiss alternatives to the strict Darwinian view, it is hard to say that Denton is erecting a strawman.

    The OP of course is entirely correct that Gould doesn't hold the views attributed by Denton to others. The thing is, in the popular literature Gould is increasingly marginal. He is widely denigrated. Punctuated equilibrium is not a phenomenon acknowledged by the popular literature. It is rarely said too bluntly, but clearly the large majority of popularizers deem Gould essentially a charlatan.

    Denton is still wrong, but he's not wrong because he's erecting a straw man.

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    1. As you know, there's a big difference between popular views and the views of knowledgeable experts. Yes, it's true that the popular view of evolution is extremely adaptationist. It's also true that the majority of biologists still have an adaptationist view of life but it's nowhere near as extreme as the popular version.

      However, if you are making a case for god based on destroying the credibility of evolution it requires a little more due diligence than just mouthing the popular view of evolution. Not even Jerry Coyne or Richard Dawkins would claim that every feature of living species requires an adaptationist explanation. (Although Richard Dawkins might have supported such a claim in the past.)

      But that wasn't my only point. Denton has demonstrated in the past that he understands non-adaptive evolution. He knows that the view he's attributing to experts in evolution is false. Not only is he erecting a strawman but he's doing it deliberately to deceive his followers.

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    2. The thing is, in the popular literature Gould is increasingly marginal. He is widely denigrated. Punctuated equilibrium is not a phenomenon acknowledged by the popular literature. It is rarely said too bluntly, but clearly the large majority of popularizers deem Gould essentially a charlatan.

      To what degree does popular literature matter here? Gould had a technical output that shaped more than one field. While for some reason PE is what he is most known for in the public, his scientific legacy consists of things like the MBL papers (which Larry just discussed in a great post) - pivotal for paleobiology. Ontogeny and Phylogeny laid the foundations of modern evo-devo and introduced a large chunk of the jargon in that field. Add the spandrels paper and his work on contingency and that would be impressive. And as far as people who are interested in the topic which PE discusses (the distribution of rates of mophological change in deep time) goes - PE is still current.

      I don't think any other popularizer of evolutionary biology (with the possible exception of EO Wilson) had that much impact on the field as a whole.

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    3. If the popular literature doesn't matter here, then it doesn't matter what Denton says either.

      Evolutionary psychology is certainly an influential movement among professional scientists, not just the overwhelmingly predominant voice in popularizations. It's hard for me to see how nuanced these professional scientists are in their conviction that natural selection is the power that molded human personality rather than culture. When they fall to arguing among themselves, as in the case of group selection, the overwhelming majority relentlessly denounce their opponents for failing to see that natural selection is too powerful to permit negative traits to emerge long enough within a group for the advantages to the group to allow differential reproduction of the group. The kin selectionist/inclusive fitness advocates insist that they have the proper understanding of evolutionary theory.



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    4. "..the overwhelming majority relentlessly denounce their opponents for failing to see that natural selection is too powerful to permit negative traits to emerge..."

      Enter the thundering fairy.

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    5. Evolutionary psychology is certainly an influential movement among professional scientists

      It's also not evolutionary biology and in fact did start out by narrowly defining its approach. I don't think that anybody from that field has even made a contribution to evolutionary biology. If you survey reading lists for evolutionary psychology courses you will find very limited material on evolutionary biology.

      The kin selectionist/inclusive fitness advocates insist that they have the proper understanding of evolutionary theory.

      I think you are missing the point. The issue is that group selection in the form advocated by the two Wilsons, Sober, etc. is mathematically equivalent to kin selection. You can partition any population into arbitrary groups and get the same result and you can always treat the whole population as one group or make each individual a group of one.
      The group selection people argue that in cases where there are groups that can be distinguished their way of expressing things is more intuitive. The other side argues that even then the groups are arbitrary and using kin selection is more parsimonous. There are no scientifically relevant differences between them (but I guess they both can draw upon a few few people that like to discuss this with high flying rhetoric...)

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    6. As near as I can see evolutionary psychology is most certainly a field of evolutionary biology. Chemists rarely cite fundamental physics or contribute papers to the field, but by and large they assume well-established physics. Evolutionary psychology is founded on the principle that natural selection has produced a human psychology fully adapted to the environment in which humans evolved. It is defended as a necessary consequence of the power of natural selection, a precept whose truth is settled science. As near as I can make out most evolutionary biologists never consider anything other than natural selection. (Indeed, it appears to me that sexual selection has usually been formulated as a special case of natural selection!) If evolutionary psychologists do the same without troubling to waste any breath mentioning random genetic drift or any other phenomenon that rarely gets more than a cursory mention, if that. If evolutionary psychology is an embarrassment for its lack of significant results? I increasingly believe it is precisely because it is just as adaptationist as the evolutionary biology they are presuming.

      As to the point, Coyne has repeatedly told us that Steven Pinker's piece on "False Allure" expressed that beautifully. This doesn't strike me as "high flying rhetoric." Nor am I aware that Coyne's views on this are less orthodox than your own. Reading Steven Frank's series on Natural Selection did strike me as an exercise in "high flying rhetoric," but he certainly didn't think the distinction was imaginary. Instead he thought group selection was misleading, i.e., wrong. But maybe I was misled by his rhetoric?

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    7. Chemists rarely cite fundamental physics or contribute papers to the field, but by and large they assume well-established physics.

      See, there are quite a few chemists that have done precisely that (contributed in major ways to physics, or work in an area where they are intimately involved with physics). EP on the other hand has decided to ignore a large chunk of evolutionary theory right from the get go - they started out by stating that they do not take common descent into account (see Cosimides and Tooby primer for instance). That is the most significant departure of EP from - say - human sociobiology.

      As near as I can make out most evolutionary biologists never consider anything other than natural selection.

      And you would be wrong there. We know that molecular evolution is mostly neutral. We know that common descent is relevant (and quite a big portion of evolutionary biologists is working on reconstructing phylogenies). We know that even in cases where we are looking at adaptive structures they tend to evolve through an interplay of drift and selection and that most beneficial alleles get lost.

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    8. Reading the Cosmides and Tooby primer did much to create my total rejection of evolutionary psychology. They wrote this:

      "Adaptationist Logic and Evolutionary Psychology

      Phylogenetic versus adaptationist explanations.

      The goal of Darwin's theory was to explain phenotypic design: Why do the beaks of finchs differ from one species to the next? Why do animals expend energy attracting mates that could be spent on survival? Why are human facial expressions of emotion similar to those found in other primates?

      Two of the most important evolutionary principles accounting for the characteristics of animals are (1) common descent, and (2) adaptation driven by natural selection. If we are all related to one another, and to all other species, by virtue of common descent, then one might expect to find similarities between humans and their closest primate relatives. This phylogenetic approach has a long history in psychology: it prompts the search for phylogenetic continuities implied by the inheritance of homologous features from common ancestors.

      An adaptationist approach to psychology leads to the search for adaptive design, which usually entails the examination of niche-differentiated mental abilities unique to the species being investigated. George Williams's 1966 book, Adaptation and Natural Selection, clarified the logic of adaptationism. In so doing, this work laid the foundations of modern evolutionary psychology. Evolutionary psychology can be thought of as the application of adaptationist logic to the study of the architecture of the human mind."

      It is news to me that George Williams rejected common descent. In the context of a discussion about how fixated current evolutionary biologists are on adaptationism, though, basing your work on George Williams puts you squarely in the mainstream. By the way, of course Cosmides and Tooby throw in some lines about other aspects of evolution...then promptly proceed to conceive the human mind as a collection of adaptations with not another word devoted to the topic.

      But I can't see that they rule out common descent, given the rather elastic temporal boundaries they give to the EEA. And Faraday, Langmuir and Pauling, all due reverence to them, I suspect are more exceptional than you allow.

      Molecular evolution to the best of my knowledge has remarkably little to say on multiplication of species. Honestly, this appears to mean there is weak support for obsession with adaptation as the be-all and end-all. It's not news to me that most beneficial alleles get lost. But reading most evolutionary biologists' adaptationist views that doesn't seem to be relevant to the history of life...if they have any concern with it in the first place.

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    9. It is news to me that George Williams rejected common descent.

      He didn't. Nor do most evolutionary psychologists, they merely ignore it (but note that Hejj for instance goes as far as stating that EP is not in any way predicated on "Darwinism", which he defines as the view "that man evolved from monkeys").

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  13. Larry, you aren't telling us something. Evolutionary biologists, and their followers, continue to worship Darwin on "Darwin Day". Why? Who is behind this craven, idiotic and anti-intellectual phenomenon? What beliefs motivate this kind of hero-worship? To what extent are these people staking out a position in the US culture war, rather than making any kind of scientific statement?

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    1. Thanks for more strawmen. At least you are sticking with the theme of the post.

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    2. Name one other ____ Day. Then we can have a discussion.

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    3. Just off the top of my head, in addition to MLK day:

      Washington's Birthday.

      Victoria Day.

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    4. "Name one other ____ Day. Then we can have a discussion."

      https://www.checkiday.com/

      https://en.wikipedia.org/wiki/Lists_of_holidays

      http://www.holidayinsights.com/moreholidays/

      http://publicholidays.us/

      https://www.daysoftheyear.com/

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    5. And here are more day names:

      https://en.wikipedia.org/wiki/Names_of_the_days_of_the_week

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    6. I refer to Dec. 25 as Newton's day as the most important scientist who ever lived was born on Dec. 25, 1643.

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    7. Check on Sir Isaac. Brains with no chains.

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    8. @Arlin: You think natural selection is not an important part of explaining adaptation? That it has been superseded and mostly replaced by neutral evolution?

      As many new phenomena have been added to our understanding of the evolutionary toolkit, I suggest that there is nothing resembling an explanation of how organisms come to be well-adapted, far better than random assemblages of atoms, without natural selection. And that Darwin arguing its importance is one of the great breakthroughs of science.

      As many scientists who say they have gone beyond Darwin, I don't think that many would suggest that we have some new major way of explaining adaptations that does not involve natural selection as a critical ingredient.

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    9. In looking at the history of life, with its long record of extinction, it is not perfectly clear to me that adaptation is everything. If it, and by extension the natural selection that produces it, were, then why is there so much species stability? I have no grasp at all how adaptation relates to the rate of extinction. Or for that matter, how it relates to the rate of speciation?

      As near as I can make out, very few evolutionary biologists are much interested in the history of life. On that scale, it seems to me an obvious proposition that natural selection is the major force conserving species morphology. Which may be huge, but appears to be the opposite of what most evolutionary biologists are saying.

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    10. The amount of work on the history of life is huge. Ever heard of molecular phylogenies? There is also much work on the evolution of quantitative characters that thinks about adaptive peaks, intermediate optima, movement or nonmovement of the optima. So conservation -- and change -- of morphology is very much on the agenda of contemporary evolutionary biology.

      S. Johnson, you're about as wrong as you can possibly be. Quite a few people are working on whether trait values affect speciation and extinction rates. And basically nobody thinks that "adaptation is everything", whatever that means.

      Have you actually looked at any evolutionary biology journals?

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  14. Martin Luther King, Jr. Day


    -jaxkayaker

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  15. OK, so what does Darwin have in common with those other people? Columbus was a rapist, torturer and murderer who brought influenza, smallpox, war-dogs, and other innovations to the new world. No one who knows what this man did likes him. But every time congress considers getting rid of Columbus Day, or maybe changing the name to something more revealing like Imperialist Subjugation of Indigenous Peoples Day, the Italian population in the US cries foul and reform is presented.

    This is because the Columbus fetish is an *identity issue* for Italian-Americans.

    Just so for Darwin Day, so far as I can see.

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    1. Agree.

      I'm not a supporter of "Darwin Day." I think it's counter-productive.

      Maybe we should have a "science day"?

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    2. @Arlin: OK, so given Columbus's horrific activities, I take it that you want to make sure that more positive figures such as Lincoln and Darwin are not put in the same category. Maybe remove their commemmorative days and look for more horrific figures?

      Personally I'd de-list Columbus, replace his Day with Indigenous People's Day, and honor Italian-Americans appropriately by a new holiday: Carlo Tresca Day. And also celebrate Darwin as well as Newton.

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    3. On a list of important issues, whether to "repeal" Columbus' and Darwin's "days" surely ranks close to the bottom.

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    4. Pssst! It's not really a 'day'. No-one takes a holiday or does anything much other than say "it's Darwin Day" ...

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    5. Ah, a tempest in a teapot no doubt. But like it or not Darwin is associated with helping to dispell a rather infantile but pervasive idea of how life arose on this planet. So pervasive that people rail against its fall to this day, for no good reasons.

      Some people celebrate enlightenment (e.g. Darwin Day). For others, it is an affront to their sensibilities. But so long as human society can be said to be, by and large, stable, progressive and non-dysfunctional, enlightenment seems to be the natural order of things (U.S. politics etc., notwithstanding).

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  16. Strictly speaking, that's a reasonable explanation of Darwinism as most evolutionary biologists understand it. But here's the problem. There aren't very many evolutionary biologists who are strict Darwinists these days even though there are many who tilt strongly in that direction.

    As far as I can see, your statement invalidates the last 2 books of Jerry Coyne and most, if not all, of Richard Dawkins.

    Larry, Can you name at least 10 of those evolutionary biologist that aren't strict Darwinists these days? What I'm asking is 10 evolutionary biologists who actually agree with you on the modern evolutionary theory that you seem to be the only one to understand and promote.

    Some may think you are bluffing, so please come up with some evidence for once!

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    1. I would name Richard Dawkins and Jerry Coyne, for starters. That gets us 20% of the way there.

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    2. Hmm. Except that he might not want to deal with you, Eric, I could name my major professor. And at least one other prof in the same department.

      I'm a taxonomist rather than an evolutionary biologist per se, but I'd agree with Dr. Moran's interpretation and I have a Ph.D., so maybe I'd count as 1/2 of an evolutionary biologist, anyway. So we're up to 5.5.

      The truth is, Eric, you'd have to search hard to find any evolutionary biologists these days who are strict Darwinists. Everybody knows neutral change in genetics happens a lot. I'd say that most knowledgeable people in the field know how neutral changes can open up new opportunities for adaptation that selection by itself couldn't. There's some variation in how much emphasis people put on this -- we hear a lot of "well, yes, that's true" as they change the topic to selection, but still, people know about this. News to you, maybe, but not to evolutionary biologists.

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    3. Should be easy of you to pick 10 names from these latest TOCs from serious molecular evolution journals...

      http://gbe.oxfordjournals.org/content/current
      http://mbe.oxfordjournals.org/content/current
      http://link.springer.com/journal/239/82/1/page/1

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  17. "we hear a lot of 'well, yes, that's true' as they change the topic to selection..."

    That strikes me as a pretty good description of "lip service." The question then is whether you're right that lip service counts as a meaningful understanding.

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    1. S Johnson, you may be right. I may be wrong to include people who shift the topic to selection in the group of those who understand neutral evolution and its implications. And yet . . .

      It seems to me that there are a lot of biologists who can lecture on the prevalence of the neutral evolution and explain its importance in terms of getting to new adaptive peaks that selection itself can't take the organism to, and yet who spend the rest of the term on variations in selection, mainly because they find the selective narratives much more compelling. "Neutral evolution is essential and yet unpredictable, here's the math, ho hum." It's hard to lecture well about what you find boring (though I have sometimes waxed much more enthusiastic about enzymes or moss reproduction than I really am.)

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