NOTE: I put up this post after the Guardian had published three letters about Buranyi’s article (below), assuming they had decided not to publish the letter by Brian Charlesworth, Deborah Charlesworth and me, which was submitted earlier. Yesterday, however, they called Brian and said they might publish our letter, so naturally I took down this post, which contains what we submitted. And in the end they decided to publish our letter, so I’m putting the original post back up, but adding in the published version as well as a superb letter by Doug Futuyma that wasn’t published. There are also the previously published letters about Buranyi’s “the theory of evolution is obsolete” paper), and the cover letter Brian wrote to the Guardian detailing a few of the factual mistakes in Buanyi’s letter. And I left in my take on the three letter the Guardian published a few days ago.
In the interests of keeping this post on the record, then, I am republishing it replacing our submitted letter with the published version, which identical to what we submitted. They added a title, but I don’t much like the one they chose.
What is indented in italics below is our introduction to the original post:
On June 28, the Guardian published an article by Stephen Buranyi, “Do we need a new theory of evolution?“, asserting that the modern theory of evolution was woefully incomplete—if not obsolete. I wrote a longish critique of the piece on this site, but of course such an egregious and misleading article needs a critique in the Guardian itself—not least because I was mentioned in the piece as a defender of the “obsolete” theory. Three other people also mentioned felt the same way: the distinguished evolutionary biologists Brian Charlesworth, Deborah Charlesworth (both at Edinburgh), and Doug Futuyma (at SUNY Stony Brook).
Brian, Deborah and I decided to write a short rebuttal letter to the paper, and Doug did so independently. Although three letters to the editor were published yesterday (see below), none of them were ours. So, with permission, I’m putting our letters here to make them available and show you what objections we wanted on the record. It may also expand your knowledge of what’s new versus what’s old in evolutionary biology.
Brian also sent a cover letter (below) detailing some of the factual errors made by Buranyi in his piece; this was not intended for publication, but to show the editors what shoddy reportage Buranyi had produced. He doesn’t seem to have done his homework. But we knew that from the article itself.
Our new letter, freshly minted in the Grauniad. Click to read it:
The rest of this post was published previously on this site, so you may have already read it. If that’s the case, ignore the following:
Brian also sent a list of errors in Buranyi’s piece in a cover letter:
I enclose a letter by Deborah Charlesworth, Jerry Coyne and myself concerning Tuesday’s Long Read article by Stephen Buranyi. All three of us were referred to in the article. We feel that the article gives a misleading account of the field of evolutionary biology, which we try to point out in our letter.
The article also contains several errors of fact, which show that Mr Buranyi has a poor understanding of the subject. Unfortunately, space does not permit us to list these in our letter. These errors could easily have been removed by proper fact-checking. We are dismayed that the Guardian would fail to ensure factual accuracy, given its famous motto.
Here are some examples.
Scientists working in the new field of genetics discovered rules that governed the quirks of heredity. But rather than confirm Darwin’s theory, they complicated it. Reproduction appeared to remix genes – the mysterious units that programme the physical traits we end up seeing – in surprising ways.
Mendelian genetics shows that maternal and paternal genes do not mix, but remain distinct from each other, in contrast to Darwin’s belief in blending of maternal and paternal contributions. This lack of blending is actually critical for variability to be maintained in populations, and hence for the effectiveness of selection. Buranyi has got it backwards.
Thomas Hunt Morgan, showed that by breeding millions of fruit flies – and sometimes spiking their food with the radioactive element radium – he could produce mutated traits, such as new eye colours or additional limbs. These were not the tiny random variations on which Darwin’s theory was built, but sudden, dramatic changes.
The artificial induction of mutations used X-rays not radium and was discovered by H.J. Muller, not Morgan. Muller was the leading expert of his time on mutations, and always emphasised that most mutations have very small or no observable effects on the organism.
… the American livestock breeder Sewall Wright…
Wright was a geneticist, not a livestock breeder (he worked on guinea pigs), and did his most famous work as a professor at the University of Chicago.
While the modern synthesists looked at life as if through a telescope, studying the development of huge populations over immense chunks of time, the molecular biologists looked through a microscope , focusing on individual molecules. And when they looked, they found that natural selection was not the all-powerful force that many had assumed it to be.They found that the molecules in our cells – and thus the sequences of the genes behind them – were mutating at a very high rate.
First, molecular evolution was first studied by comparing protein sequences from quite distantly related species, so large “chunks of time” are indeed involved. Second, the major proponent of the neutral theory of molecular evolution (to which this passage refers) was not a molecular biologist but the theoretical population geneticist Motoo Kimura. Third, this statement confuses the rate of evolution of sequences with mutation rates. It is true that these are the same under the neutral theory, but the rates are not “very high”- about 1 in 100 million per DNA site per generation in humans.
Letter to Guardian from Doug Futuyma (apparently not to be published):
Stephen Buranyi (Guardian, June 28, 2022) has provided a sensationalistic portrayal of a controversy in evolutionary biology, pitting supporters of an “Extended Evolutionary Synthesis” (EES) against the “evolutionary synthesis” (ES) of the 1930s and 1940s. He quotes my assertion that the ES “remains, mutatis mutandis, the core of modern evolutionary biology.” It is that. But in that paper, and at the London meeting of the Royal Society to which Mr. Buranyi refers, I described the history of evolutionary biology in the last 80 years as one of constant expansion, in which new subfields such as evolutionary ecology and evolutionary physiology developed, and which was profoundly changed when molecular biology provided new research tools. Almost all the new knowledge has been compatible with, yet has amplified, the ES.
Mr. Buranyi describes some past challenges to the ES. Traditional evolutionary biologists were, indeed, taken aback by evidence that considerable evolution at the DNA level was due not to natural selection, but to random genetic drift – which had already been developed in theory by the geneticists who led the ES. They were taken aback not because of blind faith in the supremacy of natural selection, but because of abundant evidence that even slight differences in organisms’ features were affected by natural selection. Random evolution at the DNA level is certainly the most thoroughgoing change, or expansion, of evolutionary biology since the ES. Mr. Buranyi portrays Eldredge and Gould’s claim of rapid, episodic evolution in fossil lineages as a violation of ES principles, but high and variable evolutionary rates were already known to authors of the ES. Eldredge and Gould departed from the ES by proposing a mechanism of episodic, rapid change that was theoretically implausible and which has not been supported by any evidence since they proposed it in 1972.
In contrast to these past challenges, most of the ideas advocated in the EES are fully compatible with traditional theory of evolution by mutation, natural selection, and genetic drift. “Niche construction” occurs when organisms choose to live in certain environments and may modify them; that this guides their evolution of adaptations (by natural selection) is obvious to anyone who compares the form and lifestyle of swallows and ducks. All organisms have some features that are “plastic,” whereby a single genotype develops different features, such as skin melanin, in different environments. Plasticity has been extensively studied since the 1940s. That it might produce novel changes that become inherited features of a species has been recognized as a possibility since the 1950s, but only recently has there been any evidence that this occurs in nature. How often is not known.
Mr. Buranyi cites the origin of complex, novel features, such as eyes, as a special challenge to the notion that mutation plus natural selection explain evolution. The steps by which eyes can have evolved from very simple precursors have been well described in molluscs and other animals, but the origin of novel features is an important theme in modern research. This question resists a simple, general answer because it requires knowing how gene mutations could give rise to novel variations – and that depends on how the relevant genes direct the development of a feature. Advances in molecular biology have clarified many developmental processes, reinvigorating the field of evolutionary developmental biology, which has illuminated the origin of some novel traits. This simply shows that a generalized theory (mutations and natural selection) needs to be particularized in order to understand the origin of any particular feature. (What are the effects of the mutations? What feature is favored by natural selection?) If we want to understand the evolution of particular proteins or physiological or anatomical traits, we need knowledge of proteins, physiology, or development. But in all cases, the ES theory is still fundamental.
Douglas J. Futuyma
Distinguished Professor Emeritus, Stony Brook University, Stony Brook, New York
Finally, click below to read the three letters that the Guardian chose for publication.
I’ll excerpt the first letter and reproduce the other two in their entirety (the third one is very short):
Jonathan Bard is listed as an evolutionary biologist, but his letter, printed first, is rather obscure, and in one place completely opaque here (my emphasis):
Stephen Buranyi misses some key points in his article (Do we need a new theory of evolution?, 28 June). Darwin saw novel speciation as resulting from natural selection acting on anatomical variants, but that simple skeleton needed fleshing out. It took a century of research, for example, for us to understand the importance of inheritance in very small populations if novel variants were to become predominant.
What is the sweating professor trying to say? Is he talking about genetic drift? Why is inheritance more important in small than in large populations?
I think what he’s trying to say is that it took a long time to understand how novel “neutral” or even maladaptive variants could rise in frequency in small populations. But that’s not even true: it took a decade or so, not a century! At any rate, neither Brian nor I can figure out what the part in bold means.
The second letter, by Nicholas Maxwell, is almost teleological!
Those biologists who are critical of current Darwinian orthodoxy and who want to modify the theory in the direction of the “extended Darwinian synthesis” need to take things further. They need to recognise that all living things are purposive. They pursue goals – without necessarily being aware of it – the ultimate goal being survival and reproductive success.
Purposive action can, in a multitude of ways, influence what has survival value – and thus influence the future course of evolution. Purposive action that results in living in a new environment, or pursuing new kinds of food, can change what has survival value for that creature and its offspring, and thus can influence the future course of evolution. Foxes hunting rabbits breed rabbits better able to escape; and rabbits escaping breed foxes better able to catch them.
Above all, when animals make discoveries and learn from one another, cultural evolution becomes possible, and that can have a massive impact on subsequent evolution, as the case of human evolution, and the evolution of language, show.
We need a new, unified version of Darwinian theory that recognises that the purposive actions of living things play a vital role in evolution. This is very definitely not Lamarckism, although too many biologists have denied the Darwinian role of purposive action in evolution for fear that that commits one to Lamarckism. For more about this, see chapter 6 of my 2020 book Our Fundamental Problem: A Revolutionary Approach to Philosophy.
Emeritus reader, science and technology studies, University College London
What looks like “purposive” action is of course behavior molded by natural selection, so the first paragraph says nothing new—but is still confusing. We have long recognized that the appearance of “purpose” is part of the appearance of “design” that is created not by God but by natural selection. The second paragraph also says nothing new: it’s been recognized for decades that an animal’s evolved behavior can change the subsequent course of natural selection (see Doug’s comment on “niche construction” above). But the example of foxes and rabbits doesn’t seem to exemplify even that point! Cultural evolution is old hat now, and “gene-culture” coevolution has been worked on for years. Finally, as I said, we already have a theory of evolution that recognizes that evolved “purposive” actions can affect future evolution! Maxwell is calling for nothing new, but simply muddies our understanding of the evolution of behavior by introducing the element of “purposiveness.” This of course will confuse lay readers who confuse the appearance of purpose with either God’s purpose or an animal’s conception of purpose.
I guess the Guardian published the third letter because the editors thought it was cute:
Surely there’s no problem with having several conflicting theories of evolution? Eventually the fittest will survive.
As Vonnegut said, “So it goes.”