Two Darwinist Conundrums

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Posted on May 13, 2014 in Darwin and Evolution, Dumb Ideas, Mind and Brain, Philosophy of Science

Darwinists should support bullying, but not rely on sexual selection.

Bully pulpit for survival

Should Darwinists promote bullying?  An article from the AAAS news site Science Now, “Better Health through Bullying,” says that bullies grow up to be stronger, while their victims grow up sicker.

Bullying casts a long shadow. Children who are bullied are more prone to depression and suicidal tendencies even when they grow up; they’re also more likely to get sick and have headaches and stomach troubles, researchers have discovered. A new study may have found the underlying cause: A specific indicator of illness, called C-reactive protein (CRP), is higher than normal in bullying victims, even when they get older. In contrast, the bullies, by the same gauge, seem to be healthier.

Clearly, the AAAS cannot go on record as supporting bullying, so the article goes on to say that bullies “should find better ways to enhance their status” without wreaking havoc on others.  But why should they?  Isn’t a healthy bully more likely to pass on its genes?  Isn’t that what drives evolution?  Bullies may not even be able to control themselves, because the article implies that bullying and victimization are related to chemicals and epigenetic factors.

The article tried to dismiss conclusions that bullying improves Darwinian fitness:

Despite the implied health benefits [i.e., fitness] of bullying, [William] Copeland [of Duke University] doesn’t advocate picking on people to better your health. The advantage probably doesn’t lie in the aggression itself, but rather in the heightened control, power, and social status that bullies enjoy, he believes.

Surely this is quibbling over terms.  If fitness is related to control, power, and social status, Darwinism couldn’t care less how the fit person attains those things.   The goal is survival of the fittest, not survival of the nicest.  Moreover, the article says that bullies attain their greatest fitness at the age of reproduction, right when their victims are suffering the most.  On what moral grounds can Copeland say anyone “should” achieve power in “better ways” than bullying?  He’s trying to moralize away something that should be a prime example of natural selection at work.

Sexual selection vs. the origin of species

Sexual selection theory is under scrutiny again, this time from a North Carolina biologist and her mathematician friend from Vienna.  Publishing in an open-access paper in PNAS entitled, “The counterintuitive role of sexual selection in species maintenance and speciation,” Maria R. Servedio announces her amazement at a counterintuitive finding: sexual selection does not lead to speciation—it erases it!

Sexual selection is generally considered to be an important force in the maintenance of species differentiation. Using population genetic models, we show that when isolated in its purest form of Fisherian sexual selection, sexual selection inhibits rather than assists species maintenance and speciation when isolated populations begin to exchange migrants. The stronger this type of sexual selection becomes, the more it erases any effects of local adaptation that drive trait divergence. Furthermore, if the strength of Fisherian sexual selection itself is allowed to evolve, sexual selection is lost. These results emphasize that additional complications have to be added to sexual selection scenarios for sexual selection to contribute to divergence; Fisherian sexual selection alone has the opposite effect.

Fisherian sexual selection, “probably the most celebrated argument in evolutionary biology” according to A. W. F. Edwards, refers to the normal form Darwin talked about in his second book, The Descent of Man, that was later elaborated on mathematically in 1930 by Ronald Fisher or perhaps others (see Wikipedia).  It’s the “intuitive” kind that Darwinists subscribe to, Servedio says:

By “Fisherian sexual selection” we are referring to sexual selection in what can be considered its most basic form, in which a genetically encoded female preference imposes differential mating success with regard to a male trait. This nonrandom mating generates linkage disequilibrium, so that evolution by sexual selection on the male trait leads to concomitant evolution of the preference itself (ref. 12, pp. 136–137). To isolate the role of Fisherian sexual selection in species maintenance we primarily consider selectively neutral female preferences. Neutrality of preferences follows the classic scenario considered in early and influential sexual selection models (4, 12, 13) and is viewed as a null model for sexual selection in its simplest form (14). In particular, this is the form of sexual selection used in the model by Lande (4) that arguably first popularized the idea of sexual selection promoting speciation and is still widely cited for this today.

Too bad it doesn’t work after all that reliance on it.  The falsification could hardly be more harsh, according to Servedio: it does the opposite of what was expected!

Speculation on the role of sexual selection in driving speciation and species maintenance traces back to the beginning of the explosion in sexual selection research seen in the past few decades (e.g., refs. 3, 4, 22, and 28). The more that this putative relationship is explored, however, the more tenuous it appears to be (e.g., refs. 10 and 11). Here we show that when sexual selection is isolated in a pure Fisherian form, it inhibits species maintenance in one of the situations in which its role seemed clearest, when the trait under sexual selection is also locally adapted.  Furthermore, sexual selection is lost in this Fisherian system if preference strengths themselves are allowed to evolve.

It only seems fair to let preference strengths evolve, if this is an evolving world. If you let it happen in the classical models, though, sexual selection vanishes away.

What are we to make of this overturn of a fundamental tenet Darwin himself promoted?  What explains the peacock’s tail?  In her Discussion section, Servedio admits she doesn’t know.  Scientists are going to have to look for more complicated selection scenarios.  She offers some alternative views, including one in which gender traits diverge apart from any selection pressure at all.  Whatever is going on, she claims that her findings are not alone:   “The finding of an inhibitory role for Fisherian sexual selection on species maintenance in our situation of geographically isolated populations exchanging migrants, although counterintuitive, falls in line with a growing body of literature that casts doubt upon the common perception of a positive contribution of sexual selection to speciation.”

Description vs. explanation

What is the point of spotting sex differences if science cannot explain them?  That’s not our question; it was asked on The Conversation by Saray Ayala-Lopez (MIT) and Nadya Vasilyeva (Brandeis University).  Their point is that it accomplishes little to just catalog differences between the sexes if no explanation for them is available.  One of the leading explanations, according to Servedio and her colleague Reinhard Burger – sexual selection – is so counterintuitive, it destroys itself.

These are not just humdrum conundrums.  They reveal that Darwinian theory is not only wrong; it’s harmful.  It doesn’t work, and it promotes bullying.  Can we kick this dead speculation out the door now?  Do you hear us, NCSE?  Can we cite these papers at the next school board meeting?  Can we let people know that Darwin’s quaint Victorian myth is bad for society?  Since when are falsehoods and incitements to violence things we should promote in school?  You don’t want the teachers rooting for the bullies now, do you?  How about a little biomimetics in the curriculum instead?

 

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