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Wednesday, February 29, 2012

Traumerei very pretty, traumer blossoms oh so sweet

(Hey, I just like having fun with the great names my readers have. How about that dude who is anti-hotel, for some reason?)

In any case, in comments elsewhere, traumerei writes: "Don't think asking for Punnett squares for memes will go over too well with users of the term."

Yes, very good point. Look at the following:
This sort of construct is a very, very early achievement of genetic science. It turned out, of course, that most genes do not work in such a straightforward fashion, and genetic science has come a long way since Mendel. But even at this early stage, we see genuine scientific results, yielding nice, mathematical, testable predictions about what will happen in certain situations.

Where, gentle reader, has "memetic science" achieved anything remotely like this? Where can we find memetics' punnett squares, that tell us what will happen when a green idea and a yellow idea "mate"?

And here is a real kicker: it turns out that there is no easily identifiable, little biochemical mechanism that can be mapped to "the gene":

"The definition of a gene is still changing. The first cases of RNA-based inheritance have been discovered in mammals. Evidence is also accumulating that the control regions of a gene do not necessarily have to be close to the coding sequence on the linear molecule or even on the same chromosome. Spilianakis and colleagues discovered that the promoter region of the interferon-gamma gene on chromosome 10 and the regulatory regions of the T(H)2 cytokine locus on chromosome 11 come into close proximity in the nucleus possibly to be jointly regulated.

"The concept that genes are clearly delimited is also being eroded. There is evidence for fused proteins stemming from two adjacent genes that can produce two separate protein products. While it is not clear whether these fusion proteins are functional, the phenomenon is more frequent than previously thought. Even more ground-breaking than the discovery of fused genes is the observation that some proteins can be composed of exons from far away regions and even different chromosomes."

In other words, "gene" is a functional concept, very useful to biologists, but without any precise physical meaning in terms of molecular biology. (As Kitcher noted in "1953 and all that.") So when someone like Dawkins (who, after all, before he became a preacher, was an ethologist, and not a molecular biologist) declares that it is "selfish genes" driving biological activity, he is saying that life is really guided by a concept invented by and convenient for biologists!

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