More than this extraordinary leap of logic, I was grated by the author's claim that such a lack of evolution would be in agreement with evolution's null-hypothesis of no biological change in the absence of changes in the physico-chemical environment, and it therefore strengthens the case for evolution.... How is it possible to cram so many errors and inaccuracies in such few words? How could the peer-reviewers let such inane nonsense appear in the title of the paper? Let us start to unravel the many mistakes in this formulation:
- What the authors call "evolution's null hypothesis" has NOT (as far as I have been able to ascertain) ever been claimed as "evolution's null hypothesis" at all: it is well-know, at least since the seminal work by Kimura, that the strongest driver of genetic variation is not the positive selection of advantageous mutations but the random fixation of neutral (or barely neutral mutations). Indeed, in humans only ca. 400 of the estimated 16500 genes show strong evidence of positive selection, even though all of the genes show variation from those of closely-related species. It is therefore NOT at all expected that genomic stasis would be observed over a long period of time. Stating (as the authors) that observing no change in these organisms is a confirmation of the mechanisms of evolution reveals a shocking lack of knowledge regarding molecular evolution. And the authors have not even proved that there was no change: that would require establishing that their ATP-producing metabolism is as efficient as that of their modern counterparts, that they are able to use the same substrates, and contain all the same enzymes, etc....
- By claiming that an unchanging environment leads to an immutable species, the authors commit a further logical fallacy: after all, there was a time (let's call it t0) when the ancestor to that community first entered that unchanging environment. If an unchanging environment leads to evolutionary stasis, then the authors are claiming that at time t0+1 million years the species would be equal to that at time t0, or that at t0+2 million years, and so forth. But of course adaptation to an environment is not instantaneous, unless the parent ancestor already possesses all enzymes needed to thrive there (and this is most unlikely, as there has been no selective pressure for that). An unchanging environment therefore causes evolutionary pressures, at least in regards to the first cells which venture there.
- When an observation is compatible with different theories, it cannot be used to further any of them: after all, seeing no change in 2 billion years could also be used to argue for the immutability of species. It is therefore logically fallacious to present it as proof that Darwin was right. Also, evolutionary theory has also developed a lot since the writing of "On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life". Shouldn't other workers, like Kimura, Felsenstein, Farris and Gould be acknowledged?
- Why would any scientist need to claim that “the findings therefore provide further scientific proof for Darwin’s work.”? Do astrophysicists need to state “the findings therefore provide further scientific proof for heliocentrism” every time that a new comet is found, its orbit is computed, and it is found to move around the sun rather than around the earth? Do anthropologists working in the Balkans need to point out that “the findings therefore provide further scientific proof that human societies do not all resemble hunter-gatherer groups?” The curious insistence of American-based media to frame biological discoveries as a supposed debate/beauty-contest between "evolution" and "creationism/immutability of species/intelligent design" is completely mind-boggling to any European, whether religious or not. This insistence was also displayed in Neil de Grasse Tyson's "Cosmos", which, unlike Sagan's masterpiece, seemed more interested in scoring debate points against a sub-section of its domestic audience than on presenting the astounding amount of knowledge mankind has gathered in the few millenia we have spent since the dawn of agriculture.
Claims unwarranted by data, exaggeration and PR stunts: all of these are usually as ascribed (rightly or not) to politicians, polemicists, salespeople and shady companies seeking to attract capital. Do we really want science to be tarred by the same brush?
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