Darwin Strauss and Popper

Robert Waldmann

Neoconservatives have expressed sympathy for “intelligent design theory,” that is, creationism. This is well documented by Ronald Bailey’s article in “Reason on line.” Bailey discusses why neoconservatives might claim they don’t believe in evolution by natural selection even though there is no scientific basis for that view.

update: link corrected thanks to VtCodger in comments.

Mainly, he suspects that it is a Strussian “noble lie,” roughly that they believe that fundamentalist religion is needed for the good of socieity, so they pretend to agree with it. He mentions, but is not very fascinated by, the idea that this is partisan hackery — that neoconservatives think the interests of the Republican party would be harmed if they didn’t bend their knees before the fundamentalists. Of course the problem is that once one decides to lie, it is very hard to decide exactly how noble to be about it.

He doesn’t mention the collosal arrogance of people who assume that biologists don’t know anything relevant about biology which they don’t know. I think this is always a risk in people coming from law or social sciences. They just have no clue how much evidence lies behind the claims of natural scientists and assume that they can bluff their way past biologists as they have successfully bluffed their way past say economomists.

In the second part of his article, Bailey argues that there is no scientific case against evolution by natural selection. Naturally it would come first, one normally doesn’t question someone’s honesty until one has exausted other options (although the NeoCons he quotes are pretty up front about how they start with the conclusion and work back to the evidence). I think the editorial decision makes sense as most Reason on Line readers don’t really need to be convinced that modern biology is not all a big mistake.

I think Bailey’s arguments for Darwin are weaker than his earlier analysis—not because he doesn’t make a convincing case, but because he buries the lede. Basically he has a theoretical disagreement with a mathematician, then speculates about the origin of life, then asks if one can be both a Christian and a Darwinist (hint yes) and only then discusses some of the evidendence for evolution by natural selection.

But Berlinski stoutly declares in Commentary that he is no creationist. He claims merely to be engaged in critiquing the failures of Darwinism. Berlinski is particularly savage about what he regards as Darwinism’s tautological character. “Time and again, biologists do explain the survival of an organism by reference to its fitness and the fitness of an organism by reference to its survival, the friction between the two concepts kindling nothing more than the observation that some creatures have been around for a very long time.”

In Berlinski’s view, evolutionary theory simply says that the ones that survive are the ones that survive. But that is not quite right. But that is not quite right. Darwinian natural selection sifts for useful variations among mutations, thus natural selection generates increased fitness, not just preserving the fittest. This process generates new species, species B being the descendant of earlier species A. This claim is clearly more than a tautology.

Wrong Bailey, the way to argue that something isn’t a tautology is to point out a testable implication. Instead Bailey claims the stated theory is not quite right because it didn’t include the word “species” even this explanation is incorrect (see below*) but the main thing is that the theory of evolution by natural selection has testable implications because organisms have detectable features which don’t make any detectable difference.

The evidence for the theory became vastly vastly enormously gigantically even more immense than it was already when biologists began sequencing DNA. They found patterns explained by the idea some sequences don’t matter and drift faster than others which do. Based on those sequences they can redraw the family tree of living things and lo and behold it almost exactly matches the tree drawn based on other features and based on fossils. Oh and one can check that the sequences that don’t seem to matter don’t matter and, so far, they don’t. Before sequencing the evidence was weaker but already overwhelming based on traights which didn’t seem important.

There might be another explanation for these facts, but no one has ever pretended to have one. Instead critics of biology like Berlinski and Kristol just ignore the evidence entirely. Bailey mentions it long after speculating at length about the origin of life (OK and I began indignantly typing before I read that far).

Berlinksi’s claim is, I think, false as a matter of fact. Biologists do not claim that the survival of this or that species is evidence in favor of evolutionary biology. The evidence all concerns trivial things which are considered evidence of evolutionary history exactly because they have tiny or zero effect on fitness.

The quote of Berlinski (all I have read of his writings) does not disprove the hypothesis that he thinks that modern evolutionary biology is completely summed up by the phrase “the survival of the fitest.” That is, indeed, a tautology. It is indeed part of the subtitle of “The Origin of Species.” But I mean, to be fair to Darwin, one should at least read the full subtitle. Oh and maybe glance at the book. And to be fair to evolutionary biology, one would have to note that much evidence has been collected since then (not to mention the theory has developed).

I have Popper in the title, because Popper did the same damn thing in “The Open Society and Its Enemies.” Popper at least asserted that something wasn’t there — predictions which have since been confirmed, explanations of puzzling facts, you know non tautological science — which absolutely wasn’t there. Popper, I think, assumed that he was brilliant enough to know what is written in a book after reading part (not all) of its subtitle.

* I think a biologist tried to explain this to Bailey and he didn’t get it. The non tautological point is that the descendents of species A might belonge to species B and C two different species present at the same time. Now the claim that two different organisms belong to different species is *not* mere terminology — it has an operational definition — orgnaisms from two different species can not produce fertile offspring descended from both of them.

If evolution were always new species A replacing now extinct species B, then all we would know is that we choose to use different words for organisms of type A and B. Without a time machine, we can’t test if they are two different species.

Now “survival of the fitest” does not logically imply that one species can, over time, split into two. This is a radical idea. It is also, in principle, experimentally testable, although the experiment will take a long time.

I personally think the experiment is under way and it is already clear that one species can split into 2 much more quickly than evolutionary biologists imagined. The experiment is raising fruit flies in laboratories. They are used to study genetics. Normal non mutant flies are called “wild type” but their ancestors haven’t been wild for about a century now. They have been bread in labs from each other.

Interestingly when an actual wild male captured in the wild is mated with a lab bread “wild type” female, something happens called “hybrid disgenisis” which means the offspring are messed up. It is known that this is caused by a transposon (basically a very very benign virus) which keeps itself inactive in the genome of wild fruit flies by making a repressor protein. None of that protein gets into spermatazoa so if the transposon is in one of the male’s chromasomes it makes copies of itself and spreads them around inside the chromasomes of the fertilized egg.

Evidently the transposon spread through the wild population after the ancestors of the lab flies were captured.

Some of the offspring survive this process. But already there is a barrier between wild and lab fruit flies after about one century. One can imagine that another hundred years or so, wild males will not be able to produce fertile offspring with lab bread females (just a few more such latent virus like things would do it).

Now to get two whole species it has to be blocked the other way too and the lab population is very isolated (also from other insects) and divided among labs so I mean maybe experimental speciation won’t occur in my grandchildren’s lifetime. But it’s really close.

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