BVSR and Control Loops are not identical

*from Tracy Harms (970101.1010 MST)

Bill Powers (970101.0500 MST)

Why should there be a "mutator gene?" If you think of all the genes as a
_system_, it would be the organization of the whole system that produces
these and other effects, just as it is the organization of the whole brain,
not a single neuron, that produces behavioral effects. I think that attempts
to find one-to-one correspondences between genes and large organizational
effects are terribly naive. It's like removing a transistor from a boom-box,
and when the music stops announcing that you've found the music transistor.

After all, we know that genes are just an organism's way of making another
organism, don't we?

On the contrary, I side with Dawkins in thinking of organisms as just a
gene's way of making another gene. That inversion may look functionally
indistinguishable at first glance, but it is not. The big question is what
is the effective unit of (de)selection. Some have thought it must be the
individual, some the species as a whole. Dawkins is the most prominent
among those who have pointed out the strength of seeing each *continuity of
characteristics* as the unit. Dawkins calls this "the gene." I favor
Barry McMullin's refinement on this topic, where he directs our attention
to similarity lineages. (McMullin's paper, _Replicators Don't!_ is
available on the World Wide Web. Barry McMullin [Home])

Tempting as the E-coli adaptive mutation-rate topic is, I'm going to turn
the attention to what I see as the problem with trying to fit evolutionary
change into a PCT mold: In an organism, and especially in a neural system
such as PCT was originally applied to, we can see a continuity of structure
in which certain changes can be considered "signals" with a lot of benefit
and few problems. PCT requires a negative-feedback loop with an effective
reference signal, a perception signal, and a comparator which produces
differential output. So far I have not found a way to successfully map
this process-pattern to evolution of the sort Wallace and Darwin pointed
to. Control loops are a *product* of evolution, and they bear at least one
key continuity with the broader evolutionary process, but they are not the
heart and soul of evolution per se. Evolution, a.k.a. adaptation by blind
variation and selective retention (BVSR), is not a control-loop phenomenon.

I am most interested to compare the structures of these two
negative-feedback patterns. Unfortunately the efforts to do so will exceed
my available attention. (I will shortly be leaving this list for a couple
of months, if not longer.) But I do hope somebody will at least continue
to point out what we don't have in the absence of such research: We don't
have an explanation which allows us to blithely speak of pan-generational
evolution as parallel to PCT feedback loops. We mustn't invoke the word
"system" on the assumption that down deep they are systemically isomorphic
-- certainly not given the fact that it is easier to find dissimilarities
than similarity between the two patterns. I hope somebody does the work of
comparing and contrasting. I'll be happy to join that project as I can.
But pending that work no equivalencing should go uncontested. (Admittedly,
I'm betting that we'll have even better contention against equivalence
after such work has been done! Whether I'm right or wrong on this,
however, a close examination would provide material of great interest to
students of evolutionary processes worldwide. I can't think of a more
natural or effective means of getting attention from a "prime-time
audience" for a detailed examination of PCT.)

Tracy Bruce Harms tbh@tesser.com
Boulder, Colorado caveat lector!