Re: Increasing Complexity

Brian D Harper (bharper@postbox.acs.ohio-state.edu)
Sat, 05 Sep 1998 19:59:28 -0400

At 09:33 AM 9/2/98 -0700, Cliff wrote:
>Brian D Harper wrote:
>
>> CL:==
>> >The only quantifiable aspect of complexity I know of is number
>> >of parts. In this limited sense segmented organisms (such as
>> >vertebrates) are decreasing in complexity. Of course complexity
>> >in every other sense may be increasing; but even so, this apparent
>> >pattern brings a non-Darwinian implication of finitude to the process.
>
>> Could you clarify why this would be a "non-Darwinian implication"?
>
>Evolution is normally thought of as an open-ended process, capable
>of anything, given enough time. The notion of morphological
>evolution 'running down'--running out of parts which are free
>to be adapted to new purposes--is not something evolutionists
>would easily accept. I don't accept it myself, in a broad view
>of evolution, but I have no choice but to accept it as fact within
>the specific context of vertebrate evolution from the Cambrian to
>the present. Theoretically a vertebrate lineage could break out of
>this pattern, but this has not been observed.
>

Thanks for the clarification. It seems to me that your characterization
"...open-ended process, capable of anything, given enough time" would
be a view associated with ultra-Darwinians. Perhaps I'm wrong, anyone
else have an opinion on this? IMHO open-ended and limitless (shorthand
for your "capable of anything") are two separate issues. In my view,
evolution is open-ended but limited. By open-ended I mean unpredictable
(for the most part, especially wrt details), non-deterministic and
capable of surprises (unexpected novelties). By limited I mean
evolution is constrained in several ways so that not everything is
possible, no matter how much time. The primary constraints would be
physical laws, historical constraints (emphasized by Gould) and
developmental constraints (emphasized by Goodwin and many others).

A humorous example of the limitless powers of natural selection is
an article written by Dawkins explaining why animals don't have
wheels. I found this on the web and if anyone's interested I might
be able to dig out the address.

Brian Harper
Applied Mechanics
Ohio State University
214 Boyd Lab
155 W. Woodruff Ave
Columbus, OH 43210

"God forbid that we should give out a dream of
our own imagination for a pattern of the world"
-- Francis Bacon