Re: Is all self-organisation evolutionary?

Alexei Sharov (sharov@VT.EDU)
Wed, 17 Mar 1999 12:08:17 -0500


Francis,

I don't know if my previous message was lost (I sent it a couple days ago
and got no reply from you). Let me know if you have not seen it, then
I'll post it again.

>As to your "entirely different definition of selection (statistical bias on
>rates of reproduction)", the only thing that is different from the one I
>use is that I put the "re" between brackets:
>
> selection is a statistical bias on the rates of (re)production of a
>particular configuration.

I agree! Now I started using the term "self-production" instead of
"self-reproduction". But I understand production differently (see below).

>If you consider that systems or states (what I call configurations) can as
>well be spontaneously *produced* as *reproduced*, then the presence of an
>attractor can be viewed as a bias toward the production of states inside
>the attractor.

Francis, you notion of production is too simplistic. In fact, it
coincides with "dynamics". If a system goes from state A to state B,
you say that state A produces state B. Then, you conclude, states
within the attractor are selectively produced. I understand production
as a semiotic relation, i.e. as a habit of producing something. This
means that the system can go from state A to several states, i.e., B, C, D,
but previous evolution have resulted in a preference (habit) of
producing B rather than C and D. This means that the system have
"remembered" what to produce. However "remembering" does not necessary
imply the presence of something like genetic code. To remember means
to remain within a particular attractor. Thus, I think that the term
"selection" should be applied to selection of attractors rather than
states. Otherwise it will be synonymous to "dynamics".

>Suppose now that I throw a tiny crystal into the solution. This will
>strongly accelerate the process: the crystal acts as an autocatalytic
>system, that boosts its own growth. The reason is that the crystal provides
>a template that helps other salt molecules find stable positions. However,
>I might as well say that the tiny fragment of crystal has started to
>*reproduce*, creating more and more pieces of crystal. If I want to mimic
>Darwinian selection, I could throw different fragments of crystal, with
>perhaps slightly different configurations, into the solution, and see which
>ones grow faster.

In this example there is a selection between several attractors that
correspond to various crystall stuctures. Each structure is "remembered".

>Of course, this is still far from Luis's "description-based reproduction"

It depends how to define "decription". It may be a text in a
well-developed valguage (e.g., genetic description), but it may be
a single attractor that determines behavior. An attractor can be
viewed as a single hieroglyphic. I would like to have a broad
definition of "description" that includes single attractors. In this
case selective crystallization will be description-based production.
But I don't know how Luis defines "descriptions".

>Moreover, by making such a strict separation, you lose the motivation to
>look at all the intermediate cases, combinations and interactions between
>"selection" and "self-organization" that are implied by a systems theory of
>evolution.

What if we restrict the term "self-organization" to transition
processes within the area of attraction of the same attractor?
Then selection works between attractors, and self-organization
is the property of an attractor? In this case the concept of
selected self-organization seems logical.

-Alexei
-------------------------------------------------
Alexei Sharov Research Scientist
Dept. of Entomology, Virginia Tech, Blacksburg, VA 24061
Tel. (540) 231-7316; FAX (540) 231-9131; e-mail sharov@vt.edu
Home page: http://www.gypsymoth.ento.vt.edu/~sharov/alexei.html