Common (hilarious!) misunderstandings
The articles, lectures, and these webpages of answers have attracted considerable critical interest from various internet bloggers, most particularly from those who seem to display their Neo-darwinian dogmatism like a badge of honour. An unfortunately frequent feature of these blogs is that they mix the dogmatism with insulting, even libellous, language. See also dogmatism.
The best advice I can give to them and their readers is ‘look before you leap’. Firing off standard ready-made criticisms before carefully reading the articles or listening through the videos to the point at which those common criticisms are clearly dealt with simply perpetuates misunderstandings. In this section I deal with examples written by critics who are clearly ‘firing off from the hip’ since the points they make are already extensively dealt with in the lectures and articles. They only had to read or watch a bit further.
Darwin was wrong?
“Here we go again: someone arguing that DARWIN WAS RONG” (sic).
This comment could not be more wide of the mark since I argue that Darwin was (largely) right! See Darwinism. Enough said.
This kind of criticism illustrates a common tactic by some Neo-Darwinists, which is to ‘recruit’ Darwin to their cause. Darwin was not a Neo-Darwinist and he even admired Lamarck. It is a simple historical mistake to conflate Darwinism with Neo-Darwinism.
Random variation. One critic complains
“What we mean by “random” is that mutations occur regardless of whether they would be good for the organism.”
Precisely so, and if the writer had read on just a little bit further (at the end of the same paragraph in which ‘random’ is first mentioned!) he would find my precisely equivalent statement: “I will use the definition that the changes are assumed to be random with respect to physiological function and could not therefore be influenced by such function or by functional changes in response to the environment. This is the assumption that excludes the phenotype from in any way influencing or guiding genetic change.”
The same ‘rapid fire’ mistake through not reading carefully is made by another blogger who wrote
“His most moronic claim by far is the one on mutations not being random.”
The extraordinary feature of this kind of criticism is that the potentially functional nature of some of the variations is the central theme of the articles and lectures. It is hard to miss that theme if one reads the article even cursorily, and it features towards the beginning of the IUPS2013 lecture. At 7:00 minutes the transcript reads “It is important here to ask what we mean by random, because it is not just a question whether the changes are truly random … but rather whether the changes are functionally relevant. That is the key.” At 7:30 minutes the transcript even uses the definition in the published article exactly as quoted above. It forms one of the slides of the lecture. In the 2012 lecture in Suzhou, China, it is made clear at 6:48 minutes and again towards the end of the lecture that the key lies in functionally significant changes. At 34:19 the transcript reads “If functional changes in the adult can be inherited, and therefore a target for natural selection, then physiology – which is the analysis of function – IS highly relevant to evolution.” It is hard to see how these points could have been made any clearer in the article and lectures. Failure to notice them implies a failure to read or watch carefully enough.
Notice again the gratuitous insults. There are even more grossly insulting and libellous remarks on the blog.
Inheritance of acquired characteristics.
“I know of not a single adaptation in organisms that is based on such environmentally-induced and non-genetic change.”
It is hard to take this kind of comment seriously. It reveals someone who is not keeping up with the literature. See Trans-generational inheritance for examples.
“For an adaptation to become fixed in a population or species, it must be inherited with near-perfect fidelity. And that is not the case for all environmentally-induced modifications of DNA. They eventually go away.”
I give examples in the lectures and article where this is clearly not true. RNA transmitted changes independent of DNA have been followed in planarians for 100 generations:
Rechavi O, Minevish G & Hobert O (2011). Transgenerational inheritance of an acquired small RNA-based antiviral response in C. elegans. Cell 147, 1248–1256.
The recent Apobec1 deficiency example from Nadeau’s laboratory is also very clear in showing “heritable epigenetic changes [that] persisted for multiple generations and were fully reversed after consecutive crosses through the alternative germ-lineage.”
Nelson VR, Heaney JD, Tesar PJ, Davidson NO & Nadeau JH (2012). Transgenerational epigenetic effects ofApobec1 deﬁciency on testicular germ cell tumor susceptibility and embryonic viability. Proc Natl Acad Sci U S A 109, E2766–E2773
Notice also the very high quality of the journals (Cell and PNAS) in which these ground-breaking studies were published.
From a much earlier period (mid 20th century), the environmentally-induced changes investigated by Waddington became locked into the DNA after about 14 generations and therefore became essentially permanent. He called this process genetic assimilation and it was one of Waddington’s great, but largely ignored, contributions.
See Trans-generational inheritance for further examples and references. To quote my article: Some of “these effects persist for many generations and are as strong as conventional genetic inheritance.”
Cells are transitory.
“Cells are transitory, and DNA is not.”
This is a common mantra, copied from The Selfish Gene. It is linguistically incoherent and factually incorrect. See Immortal Genes?
“These kinds of changes are rare except in bacteria.”
Barbara McClintock received her Nobel Prize for jumping genes in 1983 for her work on plants. The examples I give in the lecture show large-scale genome reorganisation across a whole range of vertebrates. Cross-species transfers are indeed rare except in bacteria. But, after all, speciation itself is rare, and there are plenty of documented examples of horizontal gene transfer from bacteria to various eukaryotes. Recent examples include:
Redrejo-Rodríguez, M, Muñoz-Espín, D, Holguera, I, Mencía, M, Salas, M, (2012). Functional eukaryotic nuclear localization signals are widespread in terminal proteins of bacteriophages. Proc. Natl. Acad. Sci. U.S.A. 109: 18482–7. “These ﬁndings show a common feature of TPs from diverse bacteriophages targeting the eukaryotic nucleus and suggest a possible common function by facilitating the horizontal transfer of genes between prokaryotes and eukaryotes.”
Acuna, R. et al (2012) Adaptive horizontal transfer of a bacterial gene to an invasive insect pest of coffee. Proc. Natl. Acad. Sci. U.S.A. 109: 4197–4202. “We identiﬁed a gene (HhMAN1) from the coffee berry borer beetle, Hypothenemus hampei, a devastating pest of coffee, which shows clear evidence of HGT from bacteria.”
Where the phenomenon is common (in prokaryotes) speciation is so rapid that microbiologists no longer find the species concept helpful.
The more (and only) serious point made by this particular critic is whether the Modern Synthesis has been modified to take account of these ‘big mutations’:
“The Modern Synthesis has expanded a bit to take account of these new genetic findings, which only recently became possible. But their discovery hardly invalidates the Synthesis.”
I think that is a matter of judgment. Some of the new findings are incompatible with the Modern Synthesis. See New or Extended Synthesis.
Origin of species. A common criticism is that speciation has been observed. Precisely so, and I don’t question that. The relevant question now is what the mechanisms were. It is common in Neo-darwinist discourse for people to conflate the fact that speciation clearly has and does occur with the specific Neo-darwinist interpretation of the mechanism by which it happens. See Origin of Species. This is part of a pattern in which any evidence for the fact of evolution is counted as evidence for Neo-darwinism. To say the least, this is sloppy thinking.
Good advice to Denis Noble.
“He might try discussing his ideas with other evolutionists and listening to their responses.”
I couldn’t agree more! I have greatly enjoyed doing so for around 40 years. The list of leading Evolutionary Biologists with whom I have interacted must now be around fifty, and they involve some well-known Neo-darwinists, including Dawkins, Maynard Smith and Wolpert. See Johnny-cum-lately.
The critical reactions so far are so extraordinarily wide of the mark that they are simply hilarious – almost a parody of academic criticism. Yet they weren’t intended to amuse, they were meant in all seriousness.
They attack positions that it is obvious I do not hold. That could have been clear from reading the articles or viewing the lectures. If the critics did that, they must have done so with remarkably closed minds or they failed to follow the logic through to their clearly stated conclusions. To miss the main statement when it is in the same paragraph as the sentence being attacked is breath-taking. It is an elementary principle of scholarship to read an article fully before writing a criticism.
The need to use abusive libellous language also speaks volumes about the confidence these people must have in their own scholarship.
So, are these critics just ‘saloon bar’ opinionators, or teenagers having fun on the internet? No, they are full university professors at major universities. And they are serious. That is what is both interesting and alarming, and why I have taken the time to answer them seriously. But how could such a major area of science have generated such philosophically naïve dogmatism?
|The MUSIC of Life: Biology Beyond the Genome ©Denis Noble|