Natural Selection: The Ghost Idol of Biology
A spirit that works in mysterious ways. Biologists cannot nail it down, but insist it can turn bacteria into biologists.
You could give Natural Selection (NS) a different name, and it would be as useless for explaining nature as NumbSkull, the spirit that explains everything according to a mythical caveman community. NumbSkull make mammoth come. NumbSkull make sky rain. NumbSkull make fire hot. Like NumbSkull, natural selection—or selection for short—is the default explanation for every observation. This ghostly spirit with mystical powers, able to take an RNA molecule and evolve it into a biochemist, works miracles, given millions of years. Don’t believe it? Incensed at this assault on a powerful scientific consensus? Shocked at blasphemy against the great Darwin? Let facts be submitted to a candid world.
(Note: read previous entry posted 10 Jan 2019 about “Clarifying the Claim” and “What to Look For” in scientific explanations using the idea of natural selection. In the following examples, you will find lots of bluff and bluster written in the dialect of Jargonwocky, but nothing of substance. In some cases, you will see failed predictions of NS: surprising results that contradicted expectations.)
Natural selection in the womb can explain health problems in adulthood (Medical Xpress). This article shows that the PhD’s at Columbia University don’t even understand their own theory. NS has nothing to do with childbirth. There’s no innovation, no origin of species here. They’re talking about inheritance of cells that survive embryonic development within the human species! “Rather than being programmed by the environment, random differences in gene expression may provide some embryos with a survival advantage, in particular when conditions are harsh.” Oh good grief. Conditions are always harsh, especially for Mom, but each one pops out as Homo sapiens sapiens.
How do complex animal signals evolve? (PLoS Biology). Author Chad M. Eliason uses “selection” 20 times. He argues about whether traits evolve more by natural selection or by sexual selection (Darwin’s 1872 hypothesis for traits that cannot be explained by natural selection). This provides him with endless forms most beautiful for storytelling: when NumbSkull’s explanations fail, bring in his consort SexySkull. Scanning the paper for instances of selection, one finds Eliason embroiled in the scientific controversies about how these pseudo-forces work and interact. Can any reader find anything that is solid, demonstrable, or measurable here? No; it’s all guesswork. For instance, after admitting how complex animal adornments are, he shows that selection can explain opposite things:
signal traits are a classic system for studying how sexual selection works because of the increased strength and constancy of sexual selection compared to natural selection [6] and the greater potential for rapid trait divergence if traits and preferences are genetically linked [7]. The idea that sexual selection drives signal diversity, as first emphasized by West-Eberhard [7], has been an important yet controversial idea in biology. For example, Seddon and colleagues [8] showed that sexual selection promotes trait divergence during speciation, while recent theoretical work [9] suggests that sexual selection might instead limit signal divergence in some contexts. This disagreement might arise, in part, from our lack of understanding of how signals are produced or whether and how signals are evolving under natural and/or sexual selection. A third explanation for disagreement over the role of social selection in driving signal diversity might be our lack of understanding of the interrelationships between different aspects of complex signals.
Which, being translated, says, ‘It could be this, or it could be that, or it could be something else, but there is disagreement, so we have a lack of understanding.’ Thank you, O great NumbSkull, for the wisdom you bestow on us clueless evolutionists.
Darwin’s finches choose parent lookalikes as mates (Nature). Here we go with Darwin’s finches again. Spurgin and Chapman say,
A preference for mating with similar individuals can have a key role in speciation. Research on Darwin’s finches suggests that individuals might use the likeness of their parents as a guide for choosing mates.
But if that is true, based on recent work by the Grants who have wasted their careers looking for evidence to support Darwin’s theory in finch beaks, then the behavior of mate choice is opposite the mythical forces of natural or sexual selection. Birds who mate with birds that look like their parents are not going to evolve; they are going to stay the same. There’s no speciation or innovation here. “Sexual imprinting” would bring evolution to a standstill. The authors revert to futureware to keep their dream alive: “Disentangling the roles of inherited and learnt mate preferences, and their consequences for speciation, is a key challenge for the future.” All that work for nothing? Peter and Rosemary Grant could still rescue their careers by explaining birds with intelligent design. That’s a lot more useful and interesting than tiny millimeter changes in beak size within subspecies that can still interbreed or hybridize.
Limits of long-term selection against Neandertal introgression (PNAS). Archaic DNA expert Svante Pääbo and friends use the word selection a whopping 51 times in this paper. Does it help? Well, sort of. It helps undermine selection by showing that NumbSkull keeps NS from working! (Remember: purifying selection and negative selection, if they do anything at all, preserve or destroy genetic information: they do not lead to innovation or speciation.) Browse all 51 instances; there is no innovation, no positive selection, no speciation. The authors don’t come to any trustworthy facts to make a case for selection, that ghost of a mysterious agent behind evolution.
Together, these demonstrate that the actions of selection against Neandertal sequence are not fully captured by the models presented here. Although it is beyond the scope of this work, it may be possible to leverage distributions of Neandertal ancestry in studying the action of selection in noncoding sequence. Challenges associated with such work include the uncertainty of the DFE [distribution of fitness effects] of mutations affecting noncoding sequence, and their dominance coefficients, potential epistatic effects of regulatory mutations, as well as the fact that a single deleterious mutation can affect a region falling into multiple functional categories at once.
Epistatic effects and pleiotropy can undermine any potentially beneficial mutations by causing damage elsewhere, like the proverbial worker who finally gets the ends to meet, only to see it come apart in the middle. The only possible thing selection is doing is operating a tug-of-war: the spirit of negative selection trying to get Neanderthal DNA out of the human genome, fighting the spirit of purifying selection trying to keep it in. It’s all subjective, foggy, and uncertain. How is copious application of Darwin Flubber helping us understand biology?
The evolution of sex determination associated with a chromosomal inversion (Nature Communications). Wade through the jargon of this paper if you must, but the upshot is another scenario using ‘selection’ as a magic wand. Their hypothesis suggests that “a new male-determining gene evolved in the inversion in response to selection against impaired male fertility in a hybridized population” of stickleback fish. Whoopee; more purifying selection. As usual, this hypothesis scores high on the perhapsimaybecouldness index. There’s nothing measurable, nothing certain, nothing trustworthy. There’s no innovation, positive selection, or origin of species. You could take the word ‘selection’ out of the paper completely and not lose anything of value for biology. This new hypothesis (actually “suggestion”) seems hardly better than its predecessors – and look what the authors have to say about them! We clarify thoughts in brackets.
Extensive theoretical studies have proposed several hypothetical models for the evolution of sex determination systems, such as genetic drift [which is just chance!], pleiotropic benefits [for example? Pleiotropy is more likely to cause damage than benefit], sex ratio selection [circular], and sexual antagonism [the war of the sexes does not create innovation]. Most of these models emphasize the importance of natural selection on fitness differences that are directly caused by, or indirectly associated with, a novel locus [chance] as a driving force [chance is not a force!] promoting transitions in sex determination systems. Despite the extensive theoretical work, possible empirical evidence is currently available only, to our knowledge, from a case study for the sexual antagonism hypothesis [the war of the sexes as Creator?], in which novel sex determiners evolve near sexually antagonistic genes by resolving intralocus sexual conflict [what? Ghost whispering wrapped in jargon]. Accordingly, the mechanisms that lead to transitions in sex determination systems remain mostly unknown. In particular, it is of fundamental importance to understand the factors that destabilize an existing sex determination system and drive the evolution of a new system. [Destabilization is observable; evolution of a new system is the problem at issue!]
After all these years of appealing to NS, now they tell us: it leaves them clueless! Natural selection theory has done nothing to bring understanding! The answer my friend, is blowing in the wind, somewhere out there in futureland.
That’s about all we can take for today. This gets so tiring looking for some beef in the Darwinburger, but somebody has to do it to prove that NS theory is useless. Every paper starts sounding the same: high perhapsimaybecouldness index, speculation, storytelling, futureware, and NO concrete case of anything improving by waving Humpty Darwin’s magic wand of selection.
We still haven’t heard from any supporters of natural selection as valid science. Come on. Give us your best shot. Just be prepared for some critical analysis, because we have a lot of experience in distinguishing baloney from beef.