Via Snail's Tails comes this podcast (dated 05 January 2006 on this page) featuring E.O. Wilson. According to Aydin (I'm a blogger so I don't fact check my sources) Wilson lays out the two fundamental laws of biology:
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All of the phenomena of biology are ultimately obedient to the laws of physics and chemistry.
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All of the phenomena of biology have arisen by evolution thru natural selection.
Everything in biology is the product of evolution. Only some biological phenomena can be attributed to natural selection. The issue of neutral versus selected (and within selected we have constrained versus adaptively evolving) is quite important in evolutionary biology -- especially molecular evolution. Claiming that natural selection is the be all and end all of evolution is guaranteed to draw the ire of some people.
For more on why evolution is not just natural selection see this post.
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Sociobiology is full of adaptationist claptrap
1) the characterization is correct (i listened)
2) wilson was (and to some extent, is) defending group selection in the 1970s, so he shouldn't be an arbiter of darwinian orthodoxy
3) but, Sociobiology is full of adaptationist claptrap, well, claptrap it maybe, but i'd often rather have that than the spandrel-of-the-gaps :)
Is it any surprise? The whole debate in the 1970s and 1980s with Dawkins/Wilson on one side and Lewontin/Gould on the other was on exactly this subject.
Don't forget that EOW is first and foremost an ant ecologist, interested mostly in levels of the organizational hierarchy from organisms on up. His view of biology (mine too) focuses on functioning organisms, not nucleotide sequences. Anything interesting that organisms do (and this goes for physiology, morphology, and biochemistry, in my opinion) almost certainly did "arise by evolution through natural selection." This includes exaptations, cooptations, etc. which (given sufficient antiquity) have been at least maintained but probably also honed and adjusted through generations of selection.
This is not to say that every feature of every organism is a perfect adaptation (the Gould/Lewontin caricature of "adaptationism") but merely that every mutation that affects survival & reproduction (i.e. virtually every biologically interesting mutation) is exposed to selection. With all of its acknowledged constraints.
CCP claims,
And the evidence for such a sweeping generalization is .....?
This is exactly the adaptationist position that Lewontin and Gould criticize. You are assuming, without evidence, that everything "interesting" must be an adaptation. That's an assumption you need to question. There are other possibilities. I suggest you re-read the Spandrels paper.
Let's consider a simple example that my friends and I were discussing at Christmas. The ability to roll your tongue is clearly a morphological trait in humans. What is the adaptive just-so story that explains why this allele is so prominent in human populations?
That's a knee-jerk response. I can assure you that I am no just-so panadaptationist; I've read Gould & Lewontin apart and together as well as more recent discussions like Rose & Lauder's Adaptation. Developmental constraints, pleiotropy, linkage, drift etc. are cheerfully acknowledged.
My point remains that, from an organismal point of view (again, I was trying to explain Wilson, whose POV is predominantly organismal), selection is ubiquitous and adaptation is real. In fact, I would go so far as to define "interesting" in this organismal context as any trait that affects the functioning of an organism in its environment. Such "organismally interesting" traits are almost by definition (and almost circularly) exposed to and subject to selection, and if they are heritable, there will be an evolutionary response to selection (which may indeed be constrained). This seems inescapable and uncontroversial to me.
So I agree that tongue-rolling probably has no adaptive explanation. I also deny that it is biologically "interesting," not because it's not a morphological trait, but because it has nothing to do with organismal function.
But I should probably know better than to try to speak for EO Wilson.
That logic seems a bit circular. Traits are interesting if they are subject to selection, therefore all interesting traits are subject to selection.
CCP says,
The real question is whether a trait affects the functioning of an organism in its environment. Adaptationists just assume that it does and therefore they assume that the trait is an adaptation. That's the beauty of just-so stories. The argument is circular but died-in-the-wool adaptationsts just can't recognize the fallacy.
The African rhinoceros has two horns but the Indian rhinoceros only has one. Do you find that interesting?
Mammals have lots of junk DNA. Does it affect the functioning of organisms in their environment? If not, does that mean it's not "interesting?"
It's easy to tell the difference between a red maple and a silver maple. Does the color of their leaves affect the functioning of the organism in its environement? Are you only interested in studying the evolution of maple trees if the answer is "yes?"
What you're saying is that you're only interested in adaptation. This is a bias that you share with Richard Dawkins and E.O. Wilson, among others. That's fine. If you want to limit your interest to just one kind of evolution then go right ahead. However, the problem with adaptationism is that you assume, without proof, that all kinds of things are adaptations when, in fact, they might not be. You risk accidentally studying something that you ought to find boring. :-)