Monday, July 09, 2007

I've been away for a while, so I'm not sure whether any of the crew at scienceblogs have had a look at David Sloan Wilson's essay sent in the latest Skeptic email by Michael Shermer. He takes Dawkins to task for having little or nothing to offer to back up his claims about the evolutionary origins of religion.

In retrospect, it is hard to fathom the zeal with which evolutionists such as Williams and Dawkins rejected group selection and developed a view of evolution as based entirely on self-interest. Williams ended Adaptation and Natural Selection with the phrase “I believe that it is the light and the way.” Here is how Dawkins recounts the period in his 1982 book The Extended Phenotype:

The intervening years since Darwin have seen an astonishing retreat from his individual-centered stand, a lapse into sloppily unconscious group-selectionism … We painfully struggled back, harassed by sniping from a Jesuitically sophisticated and dedicated neo-group-selectionist rearguard, until we finally regained Darwin’s ground, the position that I am characterizing by the label ‘the selfish organism…”

This passage has all the earmarks of fundamentalist rhetoric, including appropriating the deity (Darwin) for one’s own cause. Never mind that Darwin was the first group selectionist. Moreover, unlike The Selfish Gene, The Extended Phenotype was written by Dawkins for his scientific peers, not for a popular audience!

In reality, the case against group selection began to unravel almost immediately after the publication of Adaptation and Natural Selection, although it was difficult to tell, given the repressive social climate. In the first place, calling genes “replicators” and “the fundamental unit of selection” is no argument at all against group selection. The question has always been whether genes can evolve by virtue of benefiting whole groups and despite being selectively disadvantageous within groups. When this happens, the gene favored by between-group selection replaces the gene favored by within-group selection in the total population. In the parlance of population genetics theory, it has the highest average effect. Re-labeling the gene selfish, just because it evolves, contributes nothing. The “gene’s eye view” of evolution can be insightful in some respects, but as an argument against group selection it is one of the greatest cases of comparing apples with oranges in the annals of evolutionary thought.

The same goes for the concept of extended phenotypes, which notes that genes have effects that extend beyond the bodies of individual organisms. Examples of extended phenotypes include a bird’s nest or a beaver’s dam. But there is a difference between these two examples; the nest benefits only the individual builder, whereas the dam benefits all of the beavers in the pond, including those who don’t contribute to building the dam. The problem of within-group selection is present in the dam example and the concept of extended phenotypes does nothing to solve it. More apples and oranges.

Worth reading the whole thing. I think you're going to see more of these...excellent 'beg to differs' from specialists in the field who have had enough of the bomb-throwing on the fundie atheist side and who don't mind pointing out that much of the time, Dawkins doesn't even understand his own field as well as he lets on.

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