UPDATE: I forgot to add this bit from Welch’s paper about the John Templeton Foundation:
It is remarkable, for example, that much of the funding for challenging current practice in evolutionary biology comes from The John Templeton Foundation (Pennisi 2016), which is committed to using science to reveal underlying purpose, and rejecting what Nagel (2012) calls “the Materialist Neo-Darwinian Conception of Nature”. But perhaps this is just history repeating itself as farce: if poetry couldn’t save us, nothing on the laundry lists [of examples that supposedly stump evolutionary theory] will either.
If you’ve been in the evolution game as long as I, you’ll have seen people repeatedly claim that there’s something seriously wrong with modern evolutionary theory. Sometimes it’s said to just need a reform, while others claim that the whole edifice is crumbling and needs demolation (Lynn Margulis was one of the latter). A recent Royal Society meeting walked the line between those two positions.
Such claims are not recent: Steve Gould and Niles Eldredge, with their theory of punctuated equilibrium proposed in the Seventies, essentially made the extreme non-Darwinian claim that big evolutionary changes happens when small populations somehow lose their “genetic equilibrium” (how wasn’t specified), and, further, that species selection was responsible for trends in the fossil record as well as adaptations themselves. More recent calls for revision point to novel phenomena like environmentally-induced “epigenetic” changes in DNA, the “phenotype-first-genes-second” view of adaptation, “structuralist” claims that adaptations are often the result of self-organizing biological material rather than natural selection, and that phenomena like “niche construction” have been sorely neglected by evolutionists.
I’ve written about this repeatedly; you can see my latest take here. The main problem with all this is that while the phenomena adduced are said to present serious challenges to neo-Darwinism, most of them (with the exception of epigenetic “Lamarckian inheritance”) really don’t: the problem is not that the phenomena can’t be accommodated by evolutionary theory, but simply that there’s a lack of evidence that these phenomena are important or widespread. “Structuralism” is one example. Others, such as “niche construction”, have long been accepted by evolutionists under another name, so what’s new is simply a neologism.
Why, among all theories, is evolution so prone to such calls for revision? It’s not like there are new data that call modern evolutionary theory into serious question, as there were when quantum mechanics challenged classical mechanics in physics. The unique susceptibility of evolutionary biology is the subject of a new paper by John J. Welch in Biology & Philosophy, “What’s wrong with evolutionary biology?“(reference below, free download). Welch is a geneticist at the University of Cambridge.
The paper is a bit long, and intended for philosophers of science as well as evolutionists, but makes a number of good points, detailing what’s unique about evolution that makes it prone to dissing. I’m not going to summarize it in detail, but will give a few of Welch’s explanations. At the outset he considers two possibilities, but dismisses one
These critiques differ greatly from one another; indeed, their conclusions range from the undeniable (“new concepts and empirical findings […] may eventually force a shift of emphasis”; Pigliucci 2007), to the more robust (“It’s wrong like phrenology is wrong. Every major tenet of it is wrong”; Lynn Margulis quoted in Kelly 1994, p. 470). Nevertheless, there are some good reasons for considering the discontent as a whole.
First, some of the critics themselves recognise a shared enterprise, with conferences or multi-authored volumes united solely by the participants’ discontent with current practice. The result is often “laundry lists” of ideas or observations which the field is urged to incorporate or emphasise, but which have little or nothing in common with each other. The only certainty is that something needs to change (Pigliucci 2007; Chorost 2013; Pennisi 2016).
Second, irrespective of the content of the individual critiques, the sheer volume and persistence of the discontent must be telling us something important about evolutionary biology. Broadly speaking, there are two possibilities, both dispiriting. Either (1) the field is seriously deficient, but it shows a peculiar conservatism and failure to embrace ideas that are new, true and very important; or (2) something about evolutionary biology makes it prone to the championing of ideas that are new but false or unimportant, or true and important, but already well studied under a different branding.
This article will argue for possibility (2). It will suggest that a few distinct and inescapable properties of evolutionary biology make the field highly likely to attract discontent, regardless of whether the criticisms have any merit.
What are these properties? Welch says they include these (some of this is my own interpretation):
- Living (and extinct) species are the result of a diverse variety of processes, historical contingencies, and unique events lost in the mists of time. Nobody can possibly master all the relevant literature, which means that people in other fields might think that there are phenomena undercutting evolutionary theory.
- “New data appear at a very rapid rate, particularly, in recent years, from molecular biology.” The new data mislead people into thinking that a new paradigm is needed. In the case of “neutral theory,” in which different forms of genes have no differential effects on fitness, a new framework was needed, but that differs from what’s going on now. (Darwin, by the way, suggested the possibility of such neutral variation in The Origin.)
- (Related to the first point): “. . .the scope [of the field] means that authors are drawn to criticize evolutionary biology when their interests and expertise lie elsewhere.” That’s certainly true of physiologist Denis Noble, who helped organize the Royal Society meeting and whose misconceptions about evolutionary biology are profound and disturbing.
- One can cherry-pick data that seem to contradict evolutionary generalizations, and then claim that the whole edifice is rotten. This is, I think, the case for epigenetic inheritance, as we have a few cases in which environmentally-induced changes in DNA methylation can be inherited—but not a particle of evidence that they’ve played a role in adaptive evolution, or even persist as genetic changes for more than a few generations.
- Evolution’s predictive power is often weak because of life’s complexity, and so “evolutionary theory” is not like the Standard Theory of physics, which makes precise predictions. Sometimes we simply have to say that “things are complicated.”
- Many people really don’t understand natural selection, and so claim it’s impotent to explain adaptations. I think this is true: someone who’s steeped in the field, and realizes that “selfish gene” is just a metaphor, for instance, might have a very different take on adaptation than do laypeople or biologists in other fields.
- Natural selection has implications, like the amorality of nature and the suffering inherent in the process, that make it unpalatable to many.
The problems discussed above have no common thread, and they apply widely in evolutionary biology. However, they coalesce in a special way for one research programme: the study of adaptive function. The goal of such research is not a precise description of evolutionary change. Instead, it aims for a strong account of phenotypic function, which is linked to a partial account of why those phenotypes exist.
He goes on to give examples of specific critiques involved in adaptation, like kin selection versus individual or group selection, but you can read that for yourself.
I wanted to add one additional reason why evolution is liable to such critiques: scientists are always out to make a name for themselves, as our currency of achievement is not money but reputation. You don’t get well known by just adding another brick to the evolutionary edifice, but you can do by pushing the wall over. That’s how Steve Gould made his name, flawed as his theories were. With all its messiness, poorly understood phenomena (what are females choosing during sexual selection?) and historical contingency, you can always assemble a list of phenomena that you can claim show severe deficiencies in evolution. But as with theological arguments, a lack of explanation doesn’t mean that we have to resort to drastic conclusions.
I want to end by putting up Welch’s explanation for why these persistent calls for reform are harmful:
If criticism of evolutionary biology is inevitable, why grouse about it? It is easy to habituate to misleading alarm calls (Cheney and Seyfarth 1988), and churlish to complain about peripheral ideas, which, by definition, have little influence on what most scientists do. However, claims that evolutionary biology is misguided or importantly incomplete are not harmless, but actively hinder progress in the field. Indeed, they do so in several ways. First, the claims misrepresent the field to the wider public. It is unfair to use guilt by association—many fine studies are cited on creationist websites—but a field that urgently needs reform is a field “in crisis” (Mazur 2010), and when it fails to reform, this lends credibility to claims that scientists are, at best, hidebound and foolish, and at worst, guilty of ideologically-motivated deception (Mazur 2010; Teresi 2011). Such claims find an eager audience among those who reject the scientific consensus on other grounds. For example, Fodor and Piattelli-Palmarini (2010) present a priori objections to (their version of) natural selection, but also include a fairly typical laundry list to add some empirical heft. Chorost (2013) criticized Nagel (2012) for not including a laundry list. Second, and within the field, the claims encourage neophilia. This makes us unwilling to build on previous work, to integrate new findings and ideas with existing explanatory frameworks, to replicate published results (Nakagawa and Parker 2015), or to solve the field’s many outstanding problems (Maynard Smith 1977; John 1981). It also distracts attention from the ways in which all biologists can do something genuinely new, such as expanding the range of study organisms. The comparative method (Maynard Smith and Halliday 1979), Krogh’s principle (Krebs 1975), and our ignorance of biodiversity (Nee 2004), all suggest that this is one way that we might usefully extend the field.
And so it goes. I have no confidence that these calls for reform will end in my lifetime—and, after all, maybe there are real revolutions in the offing, or some striking finding that casts serious doubt on modern evolutionary theory. (I doubt that will happen.) But I’m tired of fighting theories that are already known to be wrong and questionable. To see an example of how good biologists can waste their time correcting “revolutions” that were wrong at the moment they were proposed, read the 1982 paper by my colleagues Brian Charlesworth, Russ Lande, and Monty Slatkin, showing that punctuated equilibrum, as a theory of process rather than just pattern, was dead in the water, contradicted by many already-known facts about biology (reference below; free link).
Welch, J. J. 2016. What’s wrong with evolutionary biology? Biol. Philos. Published online: doi 10.1007/s10539-016-9557-8
Charlesworth, B., R. Lande, and M. Slatkin. 1982. A Neo-Darwinian commentary on macroevolution. Evolution 36:474-498.