Yes, the folks who want evolutionary biology to be radically expanded to take into account phenomena like development, “niche construction,” culture, and epigenetics are at it again, and again they have nothing to offer but a few lab examples mixed with a lot of hype. And the promoter of this view is once again Kevin Laland from the University of St Andrews, who has published a new piece in Aeon, “Science in flux: Is evolutionary science due for a major overhaul, or is talk of a ‘revolution’ misguided? Now Laland is not just a dispassionate person who sees evolution neglecting these areas, for he’s head of a £5.7 million Templeton grant “to further our understanding of evolution.” Templeton has donated a lot of money lately to projects trying to revise or dismantle the current neo-Darwinian view of evolution. I’m not quite sure how this fits into their science-loves-religion agenda, but it must.
To Laland and his co-investigators, “furthering our understanding of evolution” means relentlessly beating the drum to say that the modern evolutionary synthesis is severely deficient, and that saviors like Laland and The Templetonians are going to fix it. Laland’s essay adds nothing to what these workers have said before (see this Nature essay and its rebuttal from four years ago)—things that I, along with others, have characterized as an overblown and careerist program designed not so much to further evolutionary biology as to advance the reputations and grant-bestowed dosh of the “revolutionaries.” (See here and here as well the Nature link and the three papers at bottom of this post.)
It’s not that development, epigenetics, and culture don’t play a role in evolution. As I’ve written before (see here and here for instance) “Evo-devo”, or the study of development and evolution, has produced great insights, like the finding that the Pax-6 gene controls eye formation in taxa as distant as flies and mice—taxa in which eyes have evolved independently. It’s just that development folds neatly into the study of evolutionary biology, and wasn’t really neglected—just laid aside until we had the molecular tools to study it. Epigenetics is important in putting marks on genes that enable cell lines to differentiate, and to produce sexual conflict in embryos, but there’s no evidence, as the touts pretend, that environmentally-induced epigenetic marks have been important in evolution. (They are almost invariably erased when gametes are formed, ergo can’t produce permanent changes). Culture has certainly played a rule in the evolution of some species: the most famous example is how lactose tolerance has evolved in human societies that keep sheep, goats and cattle. Culturally inherited songs learned by “brood parasites” in birds can initiate speciation when a parasite lays its eggs in the “wrong” nest and thus gets imprinted on a new host, and so on. But these have been studied for years (remember the blue tits who learned to drink cream by piercing milk bottles?), and the idea that culture can change selective pressures on genes is hardly revolutionary. (Do remember, too that the vast majority of species on this planet don’t have cultures that can pass on nongenetic information between generations.)
The problem is not that these phenomena aren’t interesting. It’s that they haven’t been shown to be ubiquitous in evolution, and some things, like “Lamarckian” epigenesis, have never been shown to be important in nature, though you can demonstrate them in the lab. Given how multifarious nature is, almost everything has happened at least once, but to call for a new view of evolution you have to show that your favored phenomenon is widespread. None of the promoters of the “extended evolutionary synthesis,” like Laland, have done that. They just keep writing the same article over and over again, adding the same tired (and sometimes flawed) handful of examples.
So Laland’s Aeon piece isn’t really new in those respects. What is new are two things. First, Laland admits that the talk of an “evolution revolution” is exaggerated: no “paradigm shift” is in the offing. Yet although such a paradigm shift may not be happening, we are still, says Laland, on the verge of a “radically different and profoundly richer account of evolution”. Second, Laland has started hitting below the belt by smearing his critics: he says that resistance to this “richer account” is the fault of “traditionally minded” evolutionists (I suppose I’m one). He’s trying to equate, I think, scientific conservatives with political conservatives.
Here’s a quote from Laland; the emphases are mine:
Why, then, are traditionally minded evolutionary biologists complaining about the misguided evolutionary radicals that lobby for paradigm shift? Why are journalists writing articles about scientists calling for a ‘revolution’ in evolutionary biology? If nobody actually wants a revolution, and scientific revolutions rarely happen anyway, what’s all the fuss about? The answer to these questions provides a fascinating insight into the sociology of evolutionary biology.
Revolution in evolution is a misattribution – a myth propagated by an unlikely alliance of conservative-minded evolutionists, creationists and the press. I don’t doubt that there are a small number of genuine, revolutionarily minded evolutionary radicals out there, but the vast majority of researchers working towards an extended evolutionary synthesis are simply ordinary, hardworking evolutionary biologists.
We all know that sensationalism sells newspapers, and articles that portend a major upheaval make for better copy. Creationists and advocates of ‘intelligent design’ also feed this impression, with propaganda that exaggerates differences of opinion among evolutionists and gives a false impression that the field of evolutionary biology is in turmoil. What’s more surprising is how commonly conservative-minded biologists play the ‘We’re under attack!’ card against their fellow evolutionists. Portraying intellectual opponents as extremist, and telling people that they are being attacked, are age-old rhetorical tricks to win debate or allegiance.
I had always associated such games with politics, not science, but now realise I was naive. Some of the behind-the-scenes shenanigans I have witnessed, seemingly designed to prevent new ideas from spreading by fair means or foul, have truly shocked me, and are out of kilter with practice in other fields that I know. Scientists, too, have careers and legacies at stake, as well as struggles for funding, power and influence. [If I were Laland, I’d look in the mirror here.] I worry that the traditionalists’ rhetoric is backfiring, creating confusion and inadvertently fuelling creationism by exaggerating division. Too many reputable scientists feel the need for change in evolutionary biology for all to be credibly dismissed as fringe elements.
Here we see a would-be Galileo crying that he’s been stifled and censored by hard-core traditionalists—evolutionary conservatives. And his critics are FUELING CREATIONISM!
In fact, “conservative-minded” evolutionists like myself, Brian and Deborah Charlesworth, and Doug Futuyma, haven’t been the ones erecting the strawman of a proposed “evolution revolution”. It was scientists themselves—people like Laland, Massimo Pigliucci and the “Altenberg 16” participants, physiologist Dennis Noble, my Chicago colleague Jim Shapiro, epigenetics-touter Eva Jablonka, and the entire panoply of scientists (yes, most of them “fringe biologists”) at The Third Way site—all of these people have either explicitly called for a revamping of evolutionary thinking and a drastic expansion of evolutionary biology, if not its replacement. (Some reject a “gene-centered” view of evolution and argue that adaptations result from “self organization”—surely non-neo-Darwinian views!) Yet none of these calls are based on any new empirical evidence that evolutionary biology needs the “radically different” take that Laland touts in his article.
Actually, “conservative-mindedness”, while it may not be good in politics, is an eminently sensible way to do science. That is, if we have a view that explains what we see pretty well, as does neo-Darwinism, then we should abandon or seriously modify that view only when enough evidence has accumulated to show that the view is full of holes or seriously deficient. That hasn’t happened with neo-Darwinism, despite Laland et al.’s endlessly repeated and largely identical screeds. Since serious evolutionists haven’t embraced Laland et al.’s views, he now tries to smear people who are careful scientists, loath to hop on new bandwagons, by calling them “conservative-minded biologists”. He even says that these “conservatives” can fuel creationism, which is a stupid and erroneous claim if I’ve ever heard one. In fact, it is people like Laland who fuel creationism: just see how often organizations like the Discovery Institute tout evolution’s “third way” and call attention to the revisionists’ criticisms of neo-Darwinism. The claim that evolutionary biology is seriously deficient because it ignores important insights is a claim tailor-made for the ID movement.
What about the substance of Laland’s Aeon essay? There isn’t much there beyond what he’s said before. He gives a few examples of epigenetic changes that can be passed on for several generations in the laboratory, but at least one of these (inheritance of fear of some odors in mice) is controversial, and the rest have no relevance to nature. Laland gives not a single example of an adaptation in nature that evolved because its initial phases involved environmentally induced changes in the DNA that somehow got passed on and then became adaptive. In the light of this gaping lacuna, why do these people keep banging on about “Lamarckian” epigenetic evolution? I can see no reason beyond the careerism that Laland imputes to the “conservatives”.
Laland talks about “gene-culture” coevolution, noting the lactose tolerance example, but that’s nothing new, and was already incorporated into evolutionary theory well before Laland starting trumpeting it. I’ve taught it for years in introductory evolution! Laland touts the importance of development as limiting the possibilities of evolutionary change, since you have to evolve adaptations in the milieu of an already-existing system of development. But that again is hardly anything new. Yet when Laland argues that evolutionary “convergence”—the evolution of similar phenotypes in very unrelated species, like the existence of marsupial “moles” that are very similar to placental moles—is too striking to involve natural selection alone, and must involve the channeling of evolution by developmental plans, he’s on shaky ground. After all, fishy appearances evolved in the ancestors of fish, ichthyosaurs, and dolphins—three groups with very different developmental systems. As Darwin said, and Charlesworth et al. emphasize (see below), animals and plants are quite plastic, and seem able to evolve remarkably similar appearances despite very different developmental systems and evolutionary backgrounds. If development severely restricted how animals could evolve, artificial selection experiments with a given end in mind would often fail. Just looking at the breeds of dogs is refutation enough of Laland’s claims.
Several readers called my attention to Laland’s essay, and as I read it I got the sinking feeling that I was just reading the same essay I’ve read many times before. And I was. Some of Laland’s words are new—like his invidious criticism of “conservative-minded evolutionists”—but there’s no new evidence adduced. Until that evidence accumulates—and we need more than one-off lab studies—there’s little call to start bashing evolutionary theory.
The claims of Laland, his fellow investigators on the Templeton grant, and the “Third Way” evolutionists have been adjudicated by evolutionists I deeply respect, and have been found wanting. These people aren’t diehard opponents of new phenomena in evolution, but rather people who change their minds only when they see evidence from nature to do so. To read three good rebuttals of Laland et al.’s self-promoting and overblown claims about the “new evolutionary synthesis”, read the papers at the bottom, which are freely available.
The dogs bark—loudly!—but the caravan moves on.
Futuyma, D. J. 2015. Can modern evolutionary theory explain macroevolution? Pp. 29-85 in E. a. N. G. Serelli, ed. Macroevolution: Explanation, Interpretation, and Evidence. Springer, Switzerland.
Haig, D. 2007. Weismann Rules! OK? Epigenetics and the Lamarckian temptation. Biology and Philosophy 22:415-428.