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To: Right Wing Professor

Note, I was careful not to attribute the obfuscation. (In a way it's the most maddening thing about the debate, because both sides use the same confusions in their polemics.)

At one level I agree with you: Behe's wrong because his assertions of non-evolvability are based on a priori probability estimates, which are necessarily bogus since we don't have an adequate understanding of the genome to functionality mapping and no one seems to have done the necessary work on the probablistic and information theoretic properties of actually occuring DNA transcription errors.

On the other hand, I'm dubious about the claims made on behalf of the neo-Darwinian synthesis, partly on the basis the fact that I hold a probably extreme view of falsifiablity and the predictive part--natural selection--usually ends up being tautolgous, and partly because the other part 'random variation' either has randomness defined away in any statistically meaningful sense, or is untested. (Try a Google search for DNA, transciption and "test for randomness" to see what I mean. Google is usually pretty good at turning up scientific papers, so the paucity is evidence of lack of evidence, if you take my meaning.)


301 posted on 05/25/2005 12:31:32 PM PDT by The_Reader_David (Christ is Risen! Christos Anesti! Khristos Voskrese! Al-Masih Qam! Hristos a Inviat!)
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To: The_Reader_David
At one level I agree with you: Behe's wrong because his assertions of non-evolvability are based on a priori probability estimates, which are necessarily bogus since we don't have an adequate understanding of the genome to functionality mapping and no one seems to have done the necessary work on the probabilistic and information theoretic properties of actually occurring DNA transcription errors.

Worse, one needs to have a probability estimate for every possible route in genome space between ancestor and progeny. A given molecule may have occupied more than one completely different function between its role in ancestor and its role in progeny. Most of the homology data we have suggests that molecules were often coopted; that a molecule, say, that functioned as an ion pump may have fortuitously added another domain and became an ion-gradient-driven mechanical device. It's improbable that a complex multimeric protein came together all at once to fulfill a role; it's much less improbable that a simpler molecule evolved to fill some role, and that a mutation caused another domain to stick, which gave it second (probably inefficient) role, which then evolved. We're a hundred years away from being able to map out the probabilities of such events.

On the other hand, I'm dubious about the claims made on behalf of the neo-Darwinian synthesis, partly on the basis the fact that I hold a probably extreme view of falsifiablity and the predictive part--natural selection--usually ends up being tautolgous, and partly because the other part 'random variation' either has randomness defined away in any statistically meaningful sense, or is untested.

Popper began with a similar view, but changed his mind.

IMO evolution makes plenty of predictions; we can make concrete predictions, for example, about the likely characteristics of as-yet-unsequenced genomes. Using maximum parsimony, for example, I can predict the likely sequence of any even moderately conserved gene in the last common ancestor of humans and rats. You can argue that that long extinct animal will never actually be sequenced to test my prediction - and that may be true (though we are getting better at getting DNA from fossilized material) but we can look at other descendants, and see if their genomes are consistent with that of my predicted ancestor.

It would have been a much less accessible movie than Jurassic Park, but if you have enough different descendants, you could plausibly propose to reconstruct a major part of the genome of a long extinct common ancestor, just by looking at the sequences of the descendants. No mosquitoes required!I can tell you, for example, with a high probability of correctness, the chemical structure of the myoglobin of the last common ancestor of the whales, even though no living whale has exactly that myoglobin. This sort of research is in its infancy, but from the properties of such gene products, we may be able to tell, say, if the ancestor lived on the land or water, how big it was, etc.. That, IMO, is quintessentially predictive.

347 posted on 05/25/2005 1:53:24 PM PDT by Right Wing Professor
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