"I feel obligated to clear up a very common but extremely mistaken view that seems to be persisting here. In Biology "evolution" does not in any way imply "improvement" nor progression towards any higher form. That is simply not part of the theory as presently understood."

I think most participants here do understand that.

The conclusion of Sharp's 'pebble' analogy was that folksongs evolved towards a form "congenial to the taste of the community, and expressive of its feelings, aspirations, and ideals" which, as I suggested before, is in tune with the Darwinian idea of adaptiveness, with community taste acting as selection pressure. That, however, is the thing I feel will be the hardest to demonstrate, because of a lack of evidence of how rural singers and listeners of 100 or 200 years ago reacted to particular musical characteristics. We puzzle, for instance, over the fact that the most dreadful tales of tragedy or murder might be sung to the jauntiest of tunes. Again, modal tunes have always been popular in the folk revival partly if not mainly because they sound so different from the commercial music of the day, but we don't really know how singers in 1900 perceived the differences.   

Sharp goes on: "Those tune-variations which appeal to the community, will be perpetuated as against those which attract the individual only. The nature of that appeal may be of two kinds. It may be an appeal to the sense of beauty i.e., aesthetic in character; or, it may be an appeal to the understanding, i.e., expressive in character."

Here he was suggesting (and, to be fair, he did admit that he was speculating) that aesthetics were a key adaptive characteristic, and thus the argument gets muddled with the very value judgements that you as a biologist want to steer clear of.

I don't disagree with any of your latest post, Pamela. Your paragraph beginning "Of course that's not the really interesting part of the conversation..." addresses exactly the kind of issues I've been trying to raise.