Monday, December 09, 2013

Razib Khan doesn't like Gould and doesn't like new-fangled ideas like "neutralism" and "random genetic drift"

The article by David Dobbs [Die, selfish gene, die] has stirred up a lot of biologists. Some of them (Coyne, Dawkins) pointed out why David Dobbs is wrong about this particular attack on Darwinian ordodoxy while others (PZ Myers) have defended Dobbs.

Razib Khan has weighed in [Evolutionary orthodoxy may be boring, but it is probably true]. I strongly disagree with his post but it's important to be clear about the disagreement. If "evolution orthodoxy" means evolution by natural selection then, yes, it is definitely true. That's not being disputed. The question isn't whether evolution orthodoxy is correct, it's whether it is sufficient.

I'm also not defending the specifics of Dobbs' article. Many of the most recent attempts to extend evolutionary theory are misguided and Dobbs happens to focus on one of these misguided attempts. However, the main point of Dobbs' article was that the "selfish gene" metaphor is an inappropriate metaphor for evolution and I agree strongly with this conclusion even though Dobbs' argument was faulty.

Razib Khan agrees that this is the main point. He says,
Dobbs has clarified the thrust of his article, but the general takeaway by many was that the science has passed Richard Dawkins by, and he’s something of an old-fashioned dinosaur. That might not have been the intent, but that’s basically going to be the implication seen by a lot of non-scientists, and people outside of evolutionary biology. I know this because my whole life I’ve run into people who know the "real deal" about evolutionary biology, and aren’t shy about telling me. When I was 13 years old I remember my science teacher explaining that he didn’t buy into Darwinism. Why? Because he accepted Stephen Jay Gould’s punctuated equilibrium, which was definitely the wave of the future. Twenty years later I don’t think much has changed. Standard evolutionary biology is being modified on the margins and edges, extended and expanded, but in a gradual and incremental fashion. Gould and his acolytes are always a decade away from overturning the established order.
Gould wrote about many things and punctuated equilibrium was only one of them. Nevertheless, it's true that if punctuated equilibria represent the dominant pattern of evolution then some of the assumptions of orthodox Darwinism are wrong. In fact, the challenge is still there even if the pattern only holds for part of the history of evolution.

The idea behind punctuated equilibrium is that evolutionary change is associated with speciation by cladogenesis. I don't know why Razib Khan dismisses this concept. Perhaps he thinks that evolution by natural selection includes the idea that speciation can lock in change?

Razib then quotes from some evolutionary biologist who doesn't like Gould. Razib then goes on to say ....
This may be harsh, but it gets to the heart of the fact that non-specialists esteem Gould far more than most working within his own purported field (I say purported, because from what I can tell Gould was a fine paleontologist. But he left much to be desired as an evolutionary theorist). An analogy with physics might be the fact that Stephen Hawking has been acclaimed as the "most brilliant mind since Einstein," mostly due to his elegant and popular series of books for the general public. Hawking is brilliant, but he stands head and shoulders above other prominent physicists (e.g., Ed Witten) in the public mind mostly because of his popular contributions, not his scientific work. This is not necessarily a problem, except when people confuse cultural popularity with intellectual eminence.
Humbug! You may disagree with Stephen Jay Gould if you want, but this sort of childish rhetoric is beyond the pale.

Let's see if Gould really "left much to be desired as an evolutionary theorist." A good place to start would be the Unofficial Stephen Jay Gould Archive. Check out the bibliography to see a list of books and papers that Gould published.

Gould, S.J. (1977) Ontogeny and phylogeny (Belknap press).

His first book was Ontogeny and Phylogeny, a masterful look at the relationship between evolution and developmental biology [Table of Contents]. This is where Gould first advocated his ideas about heterochrony and his coverage of neoteny is still one of the best in the business. Gould discussed heterochrony in several additional publications. Just because most people haven't got a clue what that means (Razib?) doesn't meant that it isn't a significant contribution to evolutionary theory.

Some of Gould's popular essays have been brilliant. I'm thinking specifically of Evolution as fact and theory but there are many, many others. You may think that the ideas are simple and straightforward but the fact is nobody else expressed them in this way before Gould wrote about them and nobody has done a better job since. On of my favorites is The Internal Brand of the Scarlet W from The lying stones of Marrakech: Penultimate reflections in natural history. That's the essay where Gould shows us what's wrong with genetic determinism and evolutionary psychology.

It seems a bit silly to dismiss these as useless contributions to evolutionary theory. Even essays like The return of hopeful monsters make a substantive contribution—but only if you take the time to understand it.

Gould, S.J. (1981) Evolution as fact and theory. Discover 2:34-37. [article]
Gould, S.J. (1977) The return of hopeful monsters. Natural history 86:22-30. [PDF]
Gould, S.J. (2001) The lying stones of Marrakech: Penultimate reflections in natural history (Random House).

As far as I'm concerned, Gould's biggest contribution to evolutionary theory was his challenge to conventional "Darwinism" as it came to be expressed in the hardened version of the Modern Synthesis. This may be what upsets Razib Khan since it's an attack on the Dawkins view of evolution and a threat to evolutionary orthodoxy. The opening salvo was the famous "Spandrels" paper with Richard Lewontin. You may not like what Gould & Lewontin have to say but it seems ridiculous to claim that it had no impact on evolutionary theory. After all, aren't we still talking about it today? [see Stephen Jay Gould Challenged the Modern Synthesis]

The attack was followed up in several papers published in the scientific literature and defended brilliantly in The New York Review of Books when Daniel Dennet launched his famous, and confused, diatribe against Gould. It baffles me how anyone can say that these aren't solid contributions to evolutionary theory—expecially because Gould was absolutely correct!

Gould, S.J., and Lewontin, R.C. (1979) The spandrels of San Marco and the Panglossian paradigm: a critique of the adaptationist programme. Proceedings of the Royal Society of London Series B Biological Sciences 205, 581-598. [doi: 10.1098/rspb.1979.0086]
Gould, S.J. (1980) Is a new and general theory of evolution emerging? Paleobiology 6:119-130. [PDF]
Gould, S.J. (1982) Darwinism and the expansion of evolutionary theory. Science 216:380-387.
Gould, S.J. (1997) Darwinian fundamentalism. New York Review of Books 44, 34-37. [PDF]
Gould, S.J. (1997) Evolution: The pleasures of pluralism. New York Review of Books 44, 47-52. [PDF]

Who can forget Wonderful Life? That's an explanation of the role of chance and contingency in the history of life. I suspect that Razib Khan and his buddies haven't read the book, or, if they have, they didn't understand it. Maybe that's because it conflicts with evolutionary orthodoxy.

I defy you to identify anyone other than Gould who has championed and explained this aspect of evolutionary theory.

We haven't even mentioned hierarchical theory and species sorting. These are brilliantly described in Gould's massive book The Structure of Evolutionary Theory. I'm the first to admit that this book is very long but it's chock full of information about evolutionary theory and it's well worth the effort it takes to read it. Razib Khan may not have been willing to make that effort and that's why he dismisses Gould as someone who has "left much to be desired as an evolutionary theorist." Whether you agree with Gould or not, it seems silly to treat him in such a manner.

Razib Khan continues ...
Every decade there’s always a new trend which is gaining traction and pushing the edge in terms of what we know about evolutionary biology. In the 1970s there was molecular neutralism, which superseded tired arguments between Fisherian selectionists and Wrightian balancing selectionists.
Gould, of course, has argued that Neutral Theory and random genetic drift have superseded the orthodox view of evolution based on the old population genetics of the 1930s. Razib's esay gets a bit confusing here so I'm not sure what version of orthodoxy he is defending. I'm pretty sure it's not one that incorporates these anti-Darwinian concepts. It seems to me as though Razib and his like-minded buddies are dismissive of Gould because they don't believe anything he says and not because they are able to recognize when their opponents have good arguments.

There was a recent tribute to Stephen Jay Gould on the 10th anniversary of his death [A Tribute to Stephen Jay Gould]. Ryan Gregory gave a talk and listed the important lessons we learned from Gould.
  1. Narrative: The details of "pure history" are important.
  2. Origins: The reasons a trait first evolved and why it still exists may be different.
  3. Exaptation: Features can become co-opted to serve new functions.
  4. Development: The connections between genotype and phenotype are important
  5. Pluralism: Small genetic changes accumulating slowly over time due to natural selection is not all there is.
  6. Contingency: Unique events can have a large influence in the long run, even if they seem minor initially.
  7. Hierarchy: Evolutionary processes can occur at multiple levels.
  8. Scholarship: Know the history of one's field.
It seems like some people still have to learn those lessons.


[Image Credit: Photograph of Stephen Jay Gould by Kathy Chapman from Lara Shirvinski at the Art Science Research Laboratory, New York (Wikipedia)]

45 comments:

  1. 2 interesting points:

    what if we will find a self replicat watch with dna?iiiiis this kind of watch is evidence for evolution or design?

    2)can a car evolve in a close room?if we will close a room for bilions years a bacteria in the room can evolve in the room into a human that will make a car= a car evolve in a close room? think about that.

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  2. you write:
    "...it's well worth the effort it takes to read it. Razib Khan may not have been willing to make that effort and that's why he dismisses Gould as someone who has "left much to be desired as an evolutionary theorist."

    See here:
    http://blogs.discovermagazine.com/gnxp/2008/07/the-structure-of-evolutionary-theory-blogging-chapter-8/#.UqX9Fo2JSKU

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  3. Wasn't Darwin's Dangerous Idea the book where Daniel Dennett announced that the theory of the evolution of language had been solved? If I remember correctly, he announced this in a footnote. I suppose the space limitations explain why he neglected to bother sketching this marvelous theory. My vague recollection that it was Steven Pinker who made this earthshaking discovery is so apt for humor that this is probably an unconscious joke.

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  4. Very good posting. I too wonder why so many in the evolution community like to pile onto Gould. In the area of coming up with provocative and thought-worthy ideas about evolutionary theory, only a tiny handful of people have ever matched him. I still use the concept of 'exaptation' just about every day in my evo class.

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  5. I'm not sure where Razib Khan is supposed to have opposed neutralism and random genetic drift. You seem to have decided that "evolution orthodoxy" is not wrong but is insufficient.

    Genetic drift has been part of the Modern Evolutionary Synthesis since at least the 1920s -- Wrights great papers from 1931 on were preceded by papers by R.A. Fisher that made use of genetic drift and by a paper by J.B.S. Haldane in 1927 that made use of it as well. The standard stochastic process model for genetic drift is called the Wright-Fisher model, and it dates from 1930 and 1931.

    Neutrality was not seriously proposed as applying to actual genetic variation until Lewontin and Hubby's 1966 paper (no, not in Crow and Kimura's 1964 paper, which used it as a null case but did not suggest that this was real). While neutral mutation as a source of genetic variation and change was under active consideration from that point on, the idea that it refuted the Modern Synthesis was a non-starter.

    Gould was an important evolutiuonary biologist, a masterful (if ultimately logorrheic) popularizer. He did much to put punctuational patterns of evolution on the map. He was joined in this by Raup, Sepkoski, Eldredge and Stanley. Their view that this required that most major change be due to species selection is not a majority view among evolutionary biologists -- their argument did not gain widespread acceptance, though it still around.

    The result of all this is that the horrible, boring, overly-orthodox Modern Synthesis has been refuted and swept into the dustbin of history -- leaving us with the not-so-horrible, not-so-orthodox, but still boring Modern Synthesis.

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    1. Joe, I'm well aware of the fact the random genetic drift was described in the 1930s. I'm well aware of the fact that you and me and a handful of others incorporated drift and neutral theory into their view of evolutionary theory back in the 1970s.

      You seem to be unaware of the fact that most biologists stll think the hardened (1959) version of the Modern Synthesis is correct. That's the version that emphasizes natural selection to the exclusion of all other mechanisms. That's why they are quite comfortable referring to it as "Darwinism" or "neo-Darwinism."

      Neutral Theory and random genetic drift represent sigificant challenges to the standard Darwinian view of evolution. I have no problem with those people who admit that orthodox evolutionary theory was substantially revised in the 1970s but that the new modern evolutionary theory hasn't been challenged since then.

      You may think this is what Razib Khan, Steve Pinker, and Jerry Coyne are saying but I think you are wrong.

      Joe, do you think that the "selfish gene" metaphor is an appropriate metaphor for EVOLUTION?

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    2. The "selfish gene" metaphor is a useful teaching device to focus people away from the idea that whole organism phenotypes spread, much as if the organisms reproduced clonally. It does not describe all of evolution, and of course the "selfish" in the name causes people who read shallowly to think that this is a statement about the evolution of selfishness.

      I disagree with you about whether most evolutionary biologists have assimilated genetic drift into their worldview. I know little about Razib Khan or Steven Pinker, but I have read Coyne and Orr's landmark book Speciation and can assure you that Jerry has a much more sophisticated view of how evolution happens than you give him credit for,

      Many up-and-coming biologists conclude that they have to market themselves and do so to the detriment of their field. This leads to newcomer Sam Bloggs announcing that "the neodarwinian evolutionary synthesis has just been overthrown" and that we all now need to adopt a brand-new synthesis ... which just happens to be the Bloggsian Synthesis. Hence people like me get allergic to weekly overthrows of the old Synthesis and declarations of a new Synthesis. The upshot of that chaos would be that the public would be massively confused and would conclude that what they have heard, that the explanation for why we have such good adaptations is natural selection, has been disproven. And that now it's explained by epigenetics. Or something. This week. And by something else next week.

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    3. Larry wrote:
      "Gould wrote about many things and punctuated equilibrium was only one of them. Nevertheless, it's true that if punctuated equilibria represent the dominant pattern of evolution then some of the assumptions of orthodox Darwinism are wrong. In fact, the challenge is still there even if the pattern only holds for part of the history of evolution."

      I can't figure out what you mean by "orthodox Darwinism" here. If you mean "only natural selection" then this is not entirely true since Punc-Eq was one of many ideas about speciation that recognized that drift and non-selective factors (e.g., population structure) will play a role. But of course there is reinforcement (which can occur under some conditions), which certainly invokes selection. But this doesn't rule out that certain characters can be fixed by drift at speciation.

      But if you mean "orthodox Darwinism = evolutionary forces, as traditionally recognized (drift, selection, migration, mutation)" then it seems that Punc-Eq can easily be reduced, and has, to these well-recognized processes, as outlined in papers by Russ Lande (e.g., 1986 Paleobiology) and also by Futuyma (Am. Nat 1987).

      And if you mean "orthodox Darwinism = gradualism" well, this was what Gould was trying point out. So one can hardly criticize orthodox Darwinism for being challenged by novel ideas. This is how science happens. But Punc-Eq doesn't make "some of the assumptions of orthodox Darwinism...wrong" as there are many cases of gradualism in the fossil record.

      Don't get me wrong, I'm a fan of Gould and his work on allometry, heterochrony, contingency, and the often-overlooked stuff on stochastic models of "clade shape" (mostly Raup's work, which prefigures a lot of coalescent work, though they emanate from different conceptual bases). And I'm also a fan of Dawkins.

      When you write, "You seem to be unaware of the fact that most biologists stll think the hardened (1959) version of the Modern Synthesis is correct. That's the version that emphasizes natural selection to the exclusion of all other mechanisms" I think this is an exaggeration, unless by "biologists" you are obviously excluding "evolutionary biologists." I can't think of a single Evolutionary Biology Ph.D. who would believe in the caricature that you ascribe to them. Biochemists, Physiologists, Molecular Biologists, etc.,--sure, they might hold that view, but they aren't trained as evolutionary biologists.

      And I don't think your view of the modern synthesis is correct. My sense is that, if anything the synthesis, with respect to population genetics, emphasized that all evolutionary forces could produce evolutionary change, and Wright, in 1945 (later extended by Kimura), developed a mathematical theory to combine these different evolutionary processes.

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    4. The "selfish gene" metaphor is a useful teaching device to focus people away from the idea that whole organism phenotypes spread, much as if the organisms reproduced clonally

      Except that most organisms *do* reproduce more or less clonally (with yes, mutation and horizontal transfer to introduce variation). The default organism on this planet isn't a diploid sexual being. That's something the Modern Synthesis (and other pillars like the so-called Biological Species Concept) doesn't seem to handle well.

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    5. I take your point, but most organisms that people think about when they think about evolution don't reproduce clonally.

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    6. Should we substitute "the selfish linkage group"? Would that make everyone happy?

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    7. @Joe
      Rather depends on the person, doesn't it? But seriously, it shouldn't come as a surprise that the most vocal complainers about the Modern Synthesis and other parts of orthodox evolutionary theory are evolutionary microbiologists like Ford Doolittle and Eugene Koonin who do spend a lot of time thinking about the evolution of near-clonal organisms. Yes, you can dismiss their complaints as grandstanding, but they aren't (or at least not entirely).

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    8. @Joe,

      I'm just as annoyed as you about weekly attempts to overthrow evolutionary theory by incorporating the latest fad. However, if you read those papers carefully you will see that the "Modern Synthesis" they are attempting to replace is the old version where natural selection is the only game in town.

      This tells me that the version of evolutionary theory that you and I prefer—the one based on modern population genetics—is NOT the one those "revolutionaries" see as the object of their attack. Ironically, these critics seem to have missed the revolution of the 60s and 70s and they end up attacking a strawman.

      The "selfish" gene metaphor was a product of that old Darwinian version of the Modern Synthesis. It has no place in modern evolutionary theory if it's supposed to be a metaphor for EVOLUTION. I agree with you that people like Jerry Coyne often say the right things if you look hard enough in their writings. Same with Richard Dawkins. On the other hand, much of what they write seems to focus almost exclusively on the power of natural selection in animals and animal behavior. This leads them to defend the idea of "selfish" genes when they should know that many genes are just "lucky."

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    9. Larry -- We disagree about what the Selfish Gene concept was supposed to be, To me it is a useful (if misleadingly named) image for teaching people who don't understand that population genetics is how the population evolves, not clonal growth of individual phenotypes. As such it was not a revolutionary conception. People who had read Hamilton and Maynard Smith (and other contemporary population genetics) knew this. It was instead a dramatic teaching device, useful for exposition to the general public and to less-informed biologists.

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    10. Jonathan Badger -- Ford Doolittle is a friend; I was pleased to attend his wonderful molecular evolution meetings under the auspices of the Canadian Institute For Advanced Research for almost two decades. He and Koonin are serious contributors to modern genomic studies of evolution of prokaryotes. But they do overdramatize from time to time, and Ford will tell you I have complained about this in the question period after one such.

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    11. Joe says,

      Larry -- We disagree about what the Selfish Gene concept was supposed to be ...

      Dawkins describes it as a "gene's-eye view of Darwinism" and I agree with Dawkins. You think that the "gene's-eye" part was a significant contribution to public understanding of evolution and I agree with you. You don't think that the "Darwinism" component is inconsistent with modern evolutionary theory and that's where we part company.

      Here's what Dawkins says in the first chapter ofThe Selfish Gene.

      ... I must argue for my belief that the best way to look at evolution is in term of selection occurring at the lowest level of all. In this belief I am heavily influenced by G.C. William's great book "Adaptation and Natural Selection."

      I think that the best way to look at evolution is to adopt a pluralist approach that recognizes the importance of non-adaptive evolution as well as the importance of natural selection. That's why my book, if it ever sees the light of day, will be called Evolution by Accident.

      Unlike you, I don't think Hamilton and Maynard-Smith made much of a contribution to modern evolutionary theory but people like Lewontin, Kimura, Jukes, Gould, Nei, and Ohta did. Unlike you, I don't think that a book that's mostly about animal behavior is a good way to teach people about evolution even if it introduces the "gene's-eye" view.

      I suspect we basically agree about that the "Selfish Gene" was supposed to be but disagree on whether it was correct.

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    12. Really? What I actually got from that is that we disagree about what the "Selfish Gene" was supposed to be but agree on whether it was correct. I think it's limited to one area of evolution: selection, and you criticize it because you think it was supposed to describe all of evolution.

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    13. I think it's limited to one area of evolution: selection, and you criticize it because you think it was supposed to describe all of evolution.

      The confusion could easily be resolved if everyone would simply refer to the "selfish gene" as a decent metaphor for natural selection while adding that there's more to evolution than natural selection. It's true that there are some biologists who are careful to make the first distinction; namely, that the selfish gene metaphor only refers to natural selection. It's also true, in spite of what you might claim. that many people see evolution and natural selection as synonyms so they fail to make the second distinction clear.

      Dawkins could have easily escaped the charge of adaptationism when he wrote The Selfish Gene in 1976 by explaining at the beginning that modern evolution includes things like Neutral Theory and random genetic drift but he wants to focus only on natural selection. He could have explained that by defining a gene as a unit of natural selection he didn't mean to imply that genes couldn't also be units of random genetic drift—in which case they wouldn't be "selfish."

      The fact that Dawkins didn't do that led most people to believe that he was writing about all of evolution and not just the part having to do with adaptation.

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    14. We're getting down to minor semantic issues now. I wouldn't say that any evolutionary biologists are unaware of drift. They merely speak carelessly from time to time. In a book about natural selection is should be unnecessary to talk about drift too unless it becomes relevant (as in the observation that in small populations most beneficial alleles become extinct). And I don't know what your basis is here for knowing what "most people" believed.

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  6. Gould is a hero of mine, along with Dawkins so thanks for defending him, Larry. Secondly, why are some biologist living in a separate universe than the palaeontologists. Most of the fossil record shows punctuated equilibrium not gradualism, this is something that has been known for a while now. Thirdly, the orthodoxy of the Modern Synthesis of evolutionary biology that rejected "Quantum Evolution" - Simpson's idea - was of course wrong, that is why we had to have Niles and Stephen to bring it back to evolutionary biology.
    Let me add, stephen was one of the biologists that put a strong case for thinking about evolution from a developmental perspective. and that we need to see evolution as a process that can be understood from multiple interacting levels, not just more details of population and qualitative genetics - that include things like drift.
    In short the selfish gene is dead - in my opinion - because there is much more to evolution than natural selection and much more to evolution than evolutionary genetics -Neutral or adaptive-!

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    1. The fossil record, if anything (and I don't think the documentation even of this is sufficient) shows punctuation, but it doesn't -- and probably can't -- show that punctuation is associated with speciation, which is what PE is about. It isn't the punctuation, per se, that most evolutionary biologists don't like. It's that association with speciation, for which there is no credible mechanism and no particular evidence. Absent speciation, stasis (again, insufficiently demonstrated as ubiquitous) is potentially interesting, but doesn't pose any significant challenge to the Modern Synthesis.

      Gould came up with a number of interesting hypothesis and wrote some interesting papers. But PE is not widely considered a great contribution to biology, with good reason.

      Nor is the selfish gene dead; it's just a metaphor for selection, not evolution as a whole.

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  7. For one very specific reason (which I won't explicate because I think that you do not like people linking to their own blogs), I have become interested in punctuated equilibrium which I know is one of the most misunderstood concepts in evolutionary biology. I therefore would like to understand this:

    The idea behind punctuated equilibrium is that evolutionary change is associated with speciation by cladogenesis.

    A clade is a group of species that contains all and not only some of the descendants of one ancestral species. Cladogenesis means the event of a new clade originating, which logically can only mean the speciation event producing a new species that would, in due course, further speciate into a clade. So cladogenesis would be every speciation event with the possible exception of those that are immediately followed by extinction. It is therefore unclear to me what 'speciation by cladogenesis' even means.

    It is possible that I have misunderstood punctuated equilibrium myself but I thought the point was really that speciation through genetic bottlenecking of marginal populations was when most morphological change happened, because large populations 'dilute' new mutations too much? And that this was basically a proposed explanation for observed stasis in the fossil record?

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    1. "Speciation by cladogenesis" is intended to distinguish branching from evolution within a single lineage, which if it goes far enough is sometimes considered speciation, especially by paleontologists. That's what "chronospecies" are supposed to be.

      You have stated one proposed explanation for the punctuated equilibria phenomenon (or supposed phenomenon). It's a bit different from the original explanation, which was Ernst Mayr's, that "coadapted gene complexes" made most new variation deleterious unless the complexes were broken up by "genetic revolutions" in small, isolated populations. But there is very little evidence for either of these explanations.

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    2. Ah, that makes sense of that, thanks. I have never understood why anagenesis is considered speciation, but then again I am not a palaeoontologist.

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    3. """That's what "chronospecies" are supposed to be."""

      I think "anagenesis" is a more common term.

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    4. Just noticed that Alex referred to anagenesis too. My bad.

      """"I have never understood why anagenesis is considered speciation"""

      Well, the way I see it, it produces a new species so in broad terms it is also "speciation". I don't think speciation is a term reserved to speciation occuring by populations breaking away from a parent population.

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    5. Well, does it produce a new species? There was one species, now there is still one species but it has merely changed. The problem is also that due to the gradual nature of evolutionary change, there is essentially no species concept that will be able to draw a line between the two.

      Biological species? But the two are one lineage, thus one reproductive community (at best they could be seen as the ends of a ring species stretched out through time instead of space).

      Genotypic cluster species? But there will have existed every intermediate, so there cannot be two discrete clusters.

      And so on. Really I think that trying to apply species boundaries in one time slice makes sense (a mouse cannot crossbreed with an oak so they are two different species) but trying to apply them across time is impossible.

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    6. The point I'm trying to make is not if anagenesis occurs or not, or the inerent problems with the concept. My point is simply that conceptually the term speciation can be applied to species produced by anagenesis. If not, I'd like someone to correct me on that. Plus, some of your criticism regarding the application of the species concept to anagenesis seem to me to also be a problem in cladogenesis. In both cases you're making an arbitrary call on where do you draw the line.

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    7. Really I think that trying to apply species boundaries in one time slice makes sense (a mouse cannot crossbreed with an oak so they are two different species) but trying to apply them across time is impossible

      I think that's the case. Discrete subdivision of a continuous succession only works when the continuity is broken, which is the case with two living species. We might look at the speciation event as the node of a Y (though not a simple 'dot'). The genetic distance between the arm-tips is the same as that between either tip and the base, all else being equal, and we feel compelled (by our own classificatory nature) to ascribe the same categories to organisms separated by "this much change" (at this point, I'm waving my arms like a fisherman!). Even the BSC would fail if we resurrected the ancestors.

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    8. That's a good example. The line is definetely more difficult to draw when it comes to anagenesis.

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  8. what is this random genetic drift you speak of?

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  9. thanks for spelling my last name right btw!

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  10. Can creationists say here there is a dispute in mechanisms by evolutionary biologists?
    if there is does it not mean someone is wrong or someone else!
    If so then why should not creationists also note one or the other is wrong and then both.
    Things like this happen, THEN , Creationists bring it up and then are ACCUSED of twisting around MINOR disagreements.
    Is this minor and if so why the huff puff!
    Why so much confusion in a theory thats not questioned by the right people?
    It seems there are problems because there is a bigger logical problem.

    Drawing conclusions about biological processes from mere biological data points whose relationship is entirely unrelated to the data point but is instead related to its CLAIMED geological sequence.
    ITs not biology issues here but geology issues and drawing connections from data points(fossils) in those geology sequences.
    One could predict that a crash of the geology sequences of deposition would utterly destroy the biology conclusions.
    SEEMS unrighteous that a biology theory relies on geology and without IT the biology would be plain wrong.
    I don't think there is any scientific biological research going on here.
    Am I missing something in my logic!?

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    1. One could predict that a crash of the geology sequences of deposition would utterly destroy the biology conclusions.

      Yes, but not by your logic however, since the currently accepted deposition dates do not utterly destroy the concept of young earth creationism.

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  11. Khan doesn't need me defending him, but he wrote reviews of the first 7 chapters of The Structure of Evolutionary Theory back in 2008. On his blog.

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  12. -Joe Felsenstein said "Hence people like me get allergic to weekly overthrows of the old Synthesis and declarations of a new Synthesis."

    Thanks for stating this Joe, I was starting to think everyone else lost their minds.

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    1. Claudio -- Thanks. The problem with casually accepting all these overthrows of the horrible boring stodgy brain-dead Modern Synthesis is that, if we casually accept Sam Bloggs's "Bloggsian Synthesis, next week we will accept Jane Scroggs's "Scroggsian Synthesis" and so on ad infinitum. People will get out of synch and now be up to date on which Synthesis is in force. And the poor public will be totally confused and end up concluding that none of us has a clue. But it would be great for the careers of Bloggs and Scroggs.

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    2. Typo in the above: should say ",,, and not be up to date ..."

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    3. People will get out of synch and not be up to date on which Synthesis is in force.

      Exactly. That's why it's such a bad idea to continue to refer to modern evolutionary theory as "The Modern Synthesis." That term is intimately associated with the now out-dated views of people like Julian Huxley and Ernst Mayr who did a lot to popularize the "Modern Synthesis" in the 1950s.

      I'm going to post a brief explanation from Futuyma's book. Let me know, Joe, whether you still think it's a good idea to continue to use the term "Modern Synthesis" and let me know whether you think most biologists have truly incorporated that way of thinking into their view of evolution.

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  13. The takeaway for the layman then is that Joe Felsenstein/John Harshman/Jerry Coyne/Richard Dawkins/Steven Pinker/Daniel Dennett spectrum is the competent one. Anyone suggesting otherwise is pretty much either a self-serving blowhard or a political flake. Evolutionary psychology is scientifically founded.

    Good things to know.

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  14. Pure trollery. I said nothing about evolutionary psychology, for example.

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    Replies
    1. Context is everything. In case you've forgotten, here's a reminder: "Jerry Coyne posted a couple of tweets (see below) from Steven Pinker (photo) at Dawkins responds to Dobbs."

      You've endorsed Coyne, who endorses Pinker, who endorses evolutionary psychology. And you've attacked Gould, who is still associated with the rejection of evolutionary psychology. I have not misplaced you in the spectrum of opinion. I was recapping the thrust of the whole discussion, not your personal opinions on a particular issue. All I know about your personal opinion on evolutionary psychology is that you find it unremarkable that Steven Pinker is cited as an authority in popular discussion of evolutionary theory.

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    2. Guilt by lengthy chain of association? Paging Sen. McCarthy.

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    3. No, I wouldn't call it MacCarthyist. I'd say we have a wonderful new inference method owing to S. Johnson's comment,. Let's see what we can do with it. Stephen Jay Goud rejected evolutionary psychology, He also was coauthor with Richard Lewontin on the "Spandrels of San Marco" paper. Now Lewontin in turn trained graduate students, who included Jerry Coyne. And, oh yes, at least one other ... who was it ... Oh I remember, it was me!

      So therefore ... um ... (what?)

      Delete
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