Once again: misguided calls for a thorough revamping of evolutionary biology

November 23, 2016 • 12:31 pm

On November 7-9 there was a special meeting of London’s Royal Society on “New Trends in Evolutionary Biology: Biological, Philosophical, and Social Science Perspectives.” I believe it was organized by Denis Noble, a physiologist who believes that modern views about evolution are ripe for a thorough revision.  Many of the speakers at the meeting are part of the “Third Way of Evolution” group, in which various mechanisms, supposedly ignored by the rest of us hidebound neo-Darwinists, are said to play major roles in evolution (the other two “ways” are creationism and Neo-Darwinism).

I’ve criticized Noble and the views of his colleagues before (see here and here, for instance). Here I’ll briefly reprise the themes of this new conference, and why I think that, while the mechanisms discussed are of interest, they pose no danger to the existing evolutionary paradigm; nor is there enough data to show that these mechanisms are common in nature—or even operate at all.

First, though, it’s worth noting that of the 26 presenters at the meeting, 10 were funded by Templeton’s “extended evolutionary synthesis” grant—an 8 million dollar grant over three years. Further, a representative of the Templeton Foundation was present at the meeting, presumably making sure his stable of prized thoroughbreds were running well. The grant and the meeting seem to me to represent one aim of Templeton: to show the weakness of the current evolutionary paradigm. Why they want to do this is beyond me, but it’s clear that the researchers funded by the grant are enthusiasts who have an agenda, one that partly includes self-promotion.

A good summary of the meeting, by the estimable Carl Zimmer, appears in Quanta Magazine as a longish piece, “Scientists seek to update evolution.” I won’t go through the issues raised, except to say they include the following four claims; and the critical take on these is not Zimmer’s but mine:

Epigenetics: This is the new “Lamarckian” view that environmentally-induced changes in the DNA, often affecting the methylation of DNA bases, could be an important contributor to evolution. The problem with this is that these changes are not permanent, and are often effaced after one or two generations. The record, I think, now stands at 31 generations before the environmentally-induced changes are wiped clean. But this provides no permanent basis for permanent adaptive change, which is the huge problem with the epigenetics “paradigm.” Further, when real adaptations can be genetically mapped in organisms, they always reside in the DNA sequence itself and not in the temporary alterations of DNA bases produced by the environment. Further, because environmentally induced epigenetic changes are temporary, they can’t participate in evolution by genetic drift, either.

Now there are adaptive epigenetic changes that are coded in the DNA itself: genes that code for instructions like, “Methylate bases at positions X, Y, and Z.” But those instructions evolved by conventional natural selection, and are not the types of epigenetic changes touted by promoters of the New Paradigm.

Development. Zimmer says some speakers emphaszied that development can constrain evolution: only certain evolutionary changes are possible given the evolved developmental system of organisms. (Haldane once used the example that humans couldn’t evolve into angels because they had neither the limb buds for wings nor the moral precursors!). But this is nothing new, and has been discussed for decades in the Modern Synthesis.

Plasticity.  As is well known, organisms can change their appearance, behavior, and physiology depending on their environment. Some of this is simply a “shock response” with no adaptive value, while other forms of plasticity are evolved adaptations that reside in the DNA (cats grow longer fur when it’s cold, rotifers develop predator-deterring spines when put in water with fish “odor”, etc.). But the New Paradigmists say that nonadaptive plasticity can actually initiate an adaptive evolutionary change. It’s not really clear how this would happen, and in fact we have no good examples of it happening. We have, on the other hand, plenty of examples of adaptive plasticity that evolved by conventional natural selection: organisms regularly exposed to different environments can, over time, evolve switchable genetic programs (as in cat fur length) to respond to a new environment.

Niche construction. This is the argument that an organism, by adapting to its current environment, actually changes the selective pressures that impinge on it, thus opening up further evolutionary pathways. The classic example, as Zimmer notes, is the beaver: by adapting to build a pond by cutting down trees and making dams, the beaver now occupies a new habitat, which also includes its lodge. That could present new ways for the beaver to evolve as it now lives in a pond-ish environment.

But this is not new, either, and fits well within the Modern Synthesis.  As Ernst Mayr once pointed out, many new adaptations evolve not by a change in the external environment itself, but by the organism behaviorally entering a new environment when that environment offers adaptive advantages. By making forays on land, for instance, lobe-finned fish suddenly were able to access a bunch of new food types previously unavailable. And of course once you’re moving about on land, selection will favor all kinds of new adaptations, like shelled eggs and big lungs that handle air. Similarly, warm-blooded animals, by evolving homeothermy, acquire a thin layer of warm air around their bodies, providing a good niche for ectoparasites, to which the animal must now adapt. I am in fact surprised that niche construction is seen as something radically new, since it follows ineluctably from adaptation itself.

While most of the participants in the Royal Society meeting espoused these kinds of revisions, you can see that they’re neither new nor nor have much EVIDENCE supporting them as strong challenges to the existing evolutionary paradigm.

After Carl Zimmer summarizes some of these matters, he mentions the pushback that people had against the idea that evolution is in trouble. I’ll just give one excerpt from his piece, involving a claim by Dennis Noble that organisms have an ability to detect stress and then rapidly rearrange their genomes to respond adaptively to that stress:

To illustrate this new view, Noble discussed an assortment of recent experiments. One of them was published last year by a team at the University of Reading. They did an experiment on bacteria that swim by spinning their long tails.

First, the scientists cut a gene out of the bacteria’s DNA that’s essential for building tails. The researchers then dropped these tailless bacteria into a petri dish with a meager supply of food. Before long, the bacteria ate all the food in their immediate surroundings. If they couldn’t move, they died. In less than four days in these dire conditions, the bacteria were swimming again. On close inspection, the team found they were growing new tails.

That didn’t sound right to Shuker [David Shuker of the University of St Andrews], and he was determined to challenge Noble after the applause died down.

“Could you comment at all on the mechanism underlying that discovery?” Shuker asked.

Noble stammered in reply. “The mechanism in general terms, I can, yes…” he said, and then started talking about networks and regulation and a desperate search for a solution to a crisis. “You’d have to go back to the original paper,” he then said.

While Noble was struggling to respond, Shuker went back to the paper on an iPad. And now he read the abstract in a booming voice.

“‘Our results demonstrate that natural selection can rapidly rewire regulatory networks,’” Shuker said. He put down the iPad. “So it’s a perfect, beautiful example of rapid neo-Darwinian evolution,” he declared.

This exemplifies the problem:  enthusiasts for the Third Way blather on about new mechanisms, and write dataless paper after dataless paper about them, but when the mechanisms are examined closely they’re found to be not so revolutionary after all.

Why, then, are people suddenly touting a revision of evolutionary theory? (This isn’t all new; Steve Gould tried it with punctuated equilibrium, proposing a mechanism for episodic evolutionary change that has now been discarded.)  One reason is, of course, that Templeton is funding this project big time. Where the money goes, so goes the research. The other was suggested at the meeting by my friend Doug Futuyma, not only an evolutionist but someone with  a deep knowledge of the history of evolutionary thought. As Zimmer reports:

“We must recognize that the core principles of the Modern Synthesis are strong and well-supported,” Futuyma declared. Not only that, he added, but the kinds of biology being discussed at the Royal Society weren’t actually all that new. The architects of the Modern Synthesis were already talking about them over 50 years ago. And there’s been a lot of research guided by the Modern Synthesis to make sense of them.

Take plasticity. The genetic variations in an animal or a plant govern the range of forms into which organism can develop. Mutations can alter that range. And mathematical models of natural selection show how it can favor some kinds of plasticity over others.

If the Extended Evolutionary Synthesis was so superfluous, then why was it gaining enough attention to warrant a meeting at the Royal Society? Futuyma suggested that its appeal was emotional rather than scientific. It made life an active force rather than the passive vehicle of mutations.

“I think what we find emotionally or aesthetically more appealing is not the basis for science,” Futuyma said.

Still, he went out of his way to say that the kind of research described at the meeting could lead to some interesting insights about evolution. But those insights would only arise with some hard work that leads to hard data. “There have been enough essays and position papers,” he said.

Doug is right–new insights could be in the offing. But, like him, I’d say, “Where’s the beef?” (The “beef” constitutes data and evidence.)

Doug has written a paper that summarizes and rebuts many of the supposedly serious challenges to modern evolutionary biology, and you can get it free by going to this link. The screen provides three items that can be read on SpringerLink for free; the second is Doug’s chapter.  Just go to “Download Sample Pages 2 PDF” at the bottom of the page, and you’ll get Doug’s whole paper for free. If you’re an evolutionist, this is a must-read paper, but I’d suggest that evolution-friendly readers have a look as well. The whole paper is worth reading, but if you want to just get Doug’s take on challenges to modern evolutionary theory, read section 4, from pages 53-70.

Finally, Suzan Mazur, a journalist who has long touted a total scrapping of modern evolutionary theory, wrote a piece about the conference at PuffHo (wouldn’t you know?) called “Pterosaurs hijack Royal Society Evo meeting.” It’s a bizarre piece, all over the map, but Mazur seems to have given up her crusade against modern evolutionary biology, now appearing to be on another (and better) crusade against Templeton’s funding of this kind of nonsense.

Bottom line: Modern evolutionary theory is not in trouble–far from it. Maybe sometime a New Paradigm will come around, but this isn’t it. The noise we heard from London, outside of a few papers by people like Futuyma, is the noise of Templeton’s prize horses jockeying for money and fame.

46 thoughts on “Once again: misguided calls for a thorough revamping of evolutionary biology

  1. I bet that these scientists have funding besides the Tempelton source too. So often scientists will hold onto incorrect or exaggerated claims because their financial situations depend on it. Such a shame.

  2. A question about the new Lamarckism. Hypothetically, wouldn’t it be possible for temporary epigenetic changes to have a lasting effect on a genome by the mechanism of genetic hitchhiking? If an epigenetic change just happens to occur near another gene that is the current subject of natural selective pressures, then isn’t it possible that the temporary epigenetic change could have a permanent effect depending on how and when natural selection works on the neighbouring gene? And couldn’t something similar work with drift: a temporary epigenetic change affecting the random distribution of the drift? Even a temporary change in distribution could have permanent effects, at least from a purely probabilistic point of view.

    This is all purely hypothetical, of course. Even if I’m making sense above, that’s not to say we have any evidence of such phenomena happening. And even if we did, it is hard to imagine that they would have such a big impact that the modern models would require serious revision. That would require some massively strong evidence, for sure.

    1. Not much hitchhiking can take place in just a few generations, and, at any rate, that’s not the claim made by these people. It’s the epigenetic change itself that becomes (somehow) permanently adaptive.

      1. “While most of the participants in the Royal Society meeting espoused these kinds of revisions, you can see that they’re neither nor nor have much…”

        Typo which is probably obvious: I think you mean neath “new” nor.

        Apologies if that’s too obvious and you don’t want these kinds of edits.

    2. Your idea about an epigenetic influence effecting the outcome of drift is interesting, but of course then it is not purely drift. People could have a look at that since it is testable.

    3. Epigenetic Lamarckism would mean: response to environment leads an epigenetic change with a phenotypic effect (thus far, just routine gene regulation or plasticity); but then the epigenetic change is stably inherited in the germline, passing on the epigenotype and associated phenotype to offspring. But, as you know, there is no evidence that epigenetic marks enter the germline and persist with sufficient stability to make them significant in evolution.

      It’s not clear to me what you envision occurring in hitchhiking. Even if an epigenetic modification were stably inherited long enough for hitchhiking to occur, what would be the evolutionary significance of a transient epigenotype that is not associated with any fitness difference increasing in frequency? Why would that make epigenetics more significant to evolution than a transient epigenotype that were directly selected (rather than hitchhiked) for a few generations?

      As for the probability distribution of drift: drift is change in genotype frequency in a population attributable to the random deaths of certain individuals, not to natural selection. When we use the word “random” in a technical sense, we should specify – random with respect to what? And, of course, drift is random with respect to the genotype of the individuals that happen to die. Thus, the probability distribution of drift is determined by the size and structure of the population and by the fundamental structure of the genome and the mechanism of inheritance. But it is, by definition, random with respect to differences in genotype – and, similarly, random with respect to differences in epigenotype.

      1. As I understand it, drift doesn’t have to be attributable to random deaths. It can also occur, in creatures with few offspring, when some alleles just don’t make it into the next generation purely by the luck of the draw.

        1. Yes, of course, I was using shorthand. Drift in asexual populations (bacteria say) would literally involve lineages within the population dying off by chance and others proliferating; in sexual species, from the point of view of an allele, loss by chance in the random process of recombination and assortment is equivalent to chance death without offspring.

    4. Good question Ed, and good job answering it yourself. 🙂 I was just talking to my students about this. I like how Neil refers to it has a “new Lamarckianism”. This rings true with a number of Creationists that are attempting to discredit biological evolution via natural selection. I asked some on my skeptical students, “How would these epigenetic changes carry on via the germ lines?” “What force would keep the gene sequence(s) methylated or unmethylated? and “How can a methylated or unmethylated sequence change a genome?” After analyzing this, we realized that epigenetics can be a very viable survival tool in some generations, but deleterious in others. Those that happen to have the beneficial epigenetic tags may pass on their DNA to the next generation but they may not have the benefits at all of what their forefathers may have had; however, the mere fact that his/her genome was carried forward, means that her genome has survived and is thus, more fit in some regard.

  3. Thanks for this update. Rigorously keeping an eye on such things and reporting on them is a lot of work.

    I’m continually impressed by your output! I wrote one or two semi-thoughtful emails this morning, and thought I was productive, but then I read your post…

    Tomorrow I will add a shot of espresso to my morning coffee and see if that helps!

  4. In the “pterosaurs hijack…” piece no pterosaurs are mentioned. However, they highlight Villareal’s (he was not invited) views, which I find highly interesting.
    I’m very sad that the field of epigenetics, which should help us understand (at least partiaĺy) the bridge between genes and phenotype, has become a kind of ridiculous Lamarckian stooge. There really is nothing in epigenetics to warrant deviation from classical evolutionary theory.

  5. … to show the weakness of the current evolutionary paradigm. Why they want to do this is beyond me …

    To fan the fading embers of cosmic mysterianism? Where there is disagreement or confusion, there remains interstitial space for the subtle, invisible hand of a force beyond materialism.

  6. If you’re going to make a mark as a scientist, doesn’t it help to challenge a currently-held paradigm rather than play on its edges? I can get why scientists would want to say what they are doing is revolutionary, rather than incremental.

    1. The word that comes to mind is Oxford Dictionaries’ word of the year, “post-truth”. Are we dealing here with scientific post-truth, “circumstances in which objective facts are less influential in shaping [scientific] . . . opinion than are appeals to emotion or personal belief” packaged with cherry-picked data and shoddy background info?

  7. Very well done. Larry Moran of course had been posting abstracts for this meeting. None of them seemed solid to me. All wordy words and smoke and mirrors touting vague as promises for a Great New Thing.
    Between the lines, it seemed to me that at least some of them were driven by an almost craven desire to be the next Fisher, Haldane, and Wright.

  8. I always thought any (supposed) paradigm shift would necessarily involve reinterpreting lots and lots and lots of evidence/data — not pole-vaulting over a wall using a slender stem of bold assertion resting stuff that might be what evidence might look like were it ever to be found.

  9. Jerry, your comments are right to the point, as are Doug Futuyma’s. For example the “niche construction” people often come to the triumphant conclusion that this shows that the organism is not passive, but an active participant in its own evolution! That strikes me as a totally unimportant issue, but they seem inspired by it. Maybe that is why Templeton wants to be involved — their involvement I think came after the EES bandwagon got rolling.

    Aside from that, to what extent is this all just an argument about what name we slap on evolutionary theory, and who gets to take credit for inventing a new theory. Even if there is no new theory.

  10. “The grant and the meeting seem to me to represent one aim of Templeton: to show the weakness of the current evolutionary paradigm. Why they want to do this is beyond me”

    With all due respect, why they want to do this seems perfectly obvious to me. The weaker evilution is, the more they can sneak goddidit into it and the less blatantly superfluous their g*d will be.

    ‘The enemy of my enemy is my friend’.

    Or, ’embrace, extend, extinguish’ to quote Micro$$oft from its Evil Empire days.

    cr

  11. I can’t help think that people are impugning too much malevolent competence to the Templeton foundation. They clearly have an overarching religious/philosophical bent but they are also funding good scientists who are doing good work. And I’ve never seen any evidence that they actively interfere with the research of the groups they are funding.

    Similarly, there are academic conferences held every single week that present themselves as vitally important and having revolutionary implications for their field. So while I understand and sympathise with the frustration expressed above, I don’t think that this event or its framing is particularly unusual or noteworthy.

    Scouring through the bizarre work of Suzan Mazur I came across this quote from Kevin Laland:

    “The extended evolutionary synthesis does not replace traditional thinking [he means neo-Darwinism], but rather can be deployed alongside it to stimulate research within evolutionary biology.”

    That doesn’t seem that objectionable to me. Although there are others in the same group who would go much further I don’t think there is a consensus on the issue.

    Ultimately, what everyone does seem to agree is that the proof will be in the pudding. If all we get are new theoretical pieces and grandiose claims without strong evidence then in time interest will fade away. As it should do. But until then there will be conferences and puff pieces…

    1. The thing is,the science Templeton supports is often dubious or “buzzword” science, such as this stuff. I have a hard time thinking of really good evolutionary biologists whose work is supported by Templeton (I don’t count people like D. S. Wilson, or even Laland, as really advancing the field. Finally, niche construction, as Joe said above, is not ALONGSIDE traditional evolutionary thinking, it’s part of it. And all we get from these Templeton funded people is, as Doug said, one suggestive and speculative paper after another, but not any new data.

      1. Sure, but again are you suggesting that other funding agencies are immune to the appeal of ‘buzzword’ science? That doesn’t accord with my experience.

        In terms of ‘really good evolutionary biologists’, isn’t that both a rather restrictive and highly subjective category? You are on firm ground in labelling D.S. Wilson as being highly controversial/a fringe figure but that’s not really the same for people like Kevin Laland or Gunter Wagner. At that point it seems to risk becoming ‘only people that I agree with are good’.

        That said, I’m really more familiar with the anthropologists/psychologists funded by Templeton and am vaguely aware that they fund some blue sky research in the physical sciences, hence why I used the more generic ‘good scientists’ and I would stand by that.

        They have also funded silly/ideological stuff and I’m not excusing that or denying their overarching agenda. I’m just noting that a lot of the critiques I see tend to rely on conspiracies that both over-exaggerate Templeton’s influence/competence and ignore the good projects/researchers it funds.

        Finally, whether niche construction is ‘alongside’ or ‘a part of’ traditional evolutionary thinking seems to delve into endless semantic debates that aren’t particularly interesting to me. For what it’s worth I agree more with your framing and think that earlier research (in all fields) tends to get short-shrift.

  12. An interesting and helpful summary. Thank you.
    I know these posts get less attention than the Trump ones. That’s partly because Most of us have little to add to such a technical post. But I will say I think the interest in flaky anti Darwinism is fundamentally due to intellectual cowardice, a reluctance to accept all the consequences of Darwin’s Dangerous Idea.

    1. Some, perhaps all contributors think they are onto something and that by bringing up what they perceive as true but little recognized biological process will advance the reach of science. I recommend reading Douglas Futuyma’s paper, if only to get an idea of how deep ‘intuitive’ anti-materialism runs in evolutionary biology. I was surprised that followers of Lynn Margulis were not there defending Gaia Theory or Symbiogenesis as replacements for Darwin. Royal Society, what has become of you?

    1. Suzan Mazur is, as I said, all over the map. Her previous 15 years has been spent trashing the Modern Synthesis and calling for its replacement, highlighting those like Noble who are careerists that denigrate modern evolutionary theory. In this present article she’s turned away from that, and I don’t understand why.

      But you do see that some, unlike a comment above, don’t just see something new alongside modern evolutionary theory, but a REPLACEMENT of modern evolutionary theory.

      1. I guess Mazur is pissed of because the reports from the meeting tell adifferent story than her book she presented as some kind of summary of the very same meeting before it even started. Bizarre, indeed.

  13. Slightly off topic, but exactly how much survival adavantage is necessary for a change in the genome to persist. I would assume that in a stable population (one new member exactly replaces one death on average or R=1 in epidemiology speak), that any sub-population with R>1 would increase its proportional representation. Or am I barking up the wrong phylogenetic tree?

    1. I don’t understand the question because it seems to conflate survival (actually, reproductive) advantages of individuals with the survival or propagation of subpopulations, which is a form of group selection.

      1. What I mean is how much survival advantage is necessary for a new trait to spread through a population? Twice as many offspring surviving to reproductive age? 10% more than those without the new trait? I hope that makes it a little clearer.

        1. There is no one answer to this. Even an extremely beneficial trait can die easily if the organism in which if first appears dies without reproduction. The first few generations are the most vulnerable and benefiical traits are more likely than not to die off then.

          However once the beneficial trait manages to spread to enough individuals, it becomes more likely than not to reach fixation even if it is only *very* slightly beneficial. Over thousands of generations, miniscule differences show themselves.

  14. As it happens, maybe this is a good place to ask for a favour:

    I’ve been preparing a workshop on causation for the local CFI chapter, and one of the debates I put my toe into reading about (which I might cover) was the debate in philosophy of biology over whether genes cause traits or whether there is too much of a “thicket” in the way to render that simple sort of statement unhelpful. I have accumulated a few things pro and con and such, but it occurred to me that a simplified (but too simplified) game where one makes up pretend gene sequences, expresses their proteins and such and leads to traits somewhow and lets the reproduce in various environments, etc. would be nifty. I know there are big simulators on computers and what not for gene expression – that’s too much. A game that illustrates some of the “arms length” might be nice. Particularly the idea of the norm of reaction, which is where a lot of the “genes *don’t* cause traits” (etc.) people start.

    The other philosophy of biology topic is the question about whether or not natural selection is usefully understood as being causal. This debate I think is hard to illustrate in any concrete way at all (game or not).

  15. I commented over Quora:

    I’m very very disappointed with the RS meeting “New Trends in Evolutionary Biology”. Reason? In the first chapter of the book “The Extended Synthesis” editors Gerd Müller and Massimo Pigliucci explained that the new synthesis (EES) overcomes the Modern Synthesis in three basic points:

    Gradualism:
    “The dynamics of biological systems illuminates the capacity of continuous selectional regimes to produce the nongradual phenotypic change frequently observed in the paleontological record.” (p. 13)

    Externalism:
    Instead of giving priority to all external factors and natural selection alone as the main cause of biological novelties the EES considers that “the specificity of its phenotypic outcome is provided by the developmental system it operates on. Hence the organisms themselves represent the determinants of selectable variations and innovation.” (p. 13)

    Gene-centrism:
    “Gen centrism necessarily disappears in an extended account that provides for multicausal evolutionary factors acting on organismal systems´ properties, including the non programmed components of environment, development and inheritance.” (p. 14)

    If one overcomes gradualism, the central role of natural selection and gene centrism in creating new phenotypic traits, as far as Darwinism is concerned, what have we got left? And what about information? I wish these scientific points were fully discussed on the RS meeting. A new general theory of evolution needs to replace the Modern Evolutionary Synthesis.

  16. I’ve read the paper by Templeton’s so-called prize horses and they are not touting a new paradigm: “Evolutionary biology has never been more vibrant, and it would be a distortion to characterize it as in a (Kuhnian) state of ‘crisis’. In the EES, all processes central to contemporary evolutionary theory (e.g. natural selection, genetic drift, Mendelian inheritance), and its empirical findings, remain important; in this respect, the EES requires no ‘revolution’.
    http://rspb.royalsocietypublishing.org/content/282/1813/20151019

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