Evolution is not progress?

Thomas Colthurst thomasc at lobachevskii.geom.umn.edu
Wed Jun 24 23:16:42 EST 1992

In article <1992Jun24.194454.9742 at hellgate.utah.edu> tolman%asylum.cs.utah.edu at cs.utah.edu (Kenneth Tolman) writes:
>  I will contend here that evolution IS associated with progress. Do you


>The original organisms survived in only a certain environment.  Genetic
>mutation gave the capability for some other organisms to survive in
>other environments.  This extension of life forms from one domain into
>a LARGER domain is progress.  It also happened with the formation of
>oxygen breathers (animals) the formation of land based life forms for
>both animals and plants, and the continued expansion into new niches.

Occupation of a "larger" enviornmental niche could be considered one
_aspect_ of progress, but even this criteria is very problematic.  For
one thing, I believe that studies of # of enviornmental niches occupied
versus time show that this index actually decreases rather dramatically.
There is a general pattern of life form diversification followed by
extinction of most of the branches.
>A particular organism with a certain functionality mutates and has an
>offspring with the same functionality with additions.  For instance,
>an organism that ends up manufacturing an additional protective
>(anti viral) enzyme has an additional functionality.  This expansion of
>functionality is progress.

Addition of mutation does not imply addition of functionality.  For instance,
it may be advantageous for a life form to strip down its functionality and
thus devote more energy to its remaining functions.  (You may be familiar
with computer programs which are overly general, and thus much slower than
a more finely tuned program.) 

>What do you think?  Of course many evolutionary trends may have nothing
>to do with progress, but some do.

And for any empirical test of "progress", there will be examples of
species evolving in the opposite direction.  Pick up a copy of "It's A
Wonderful Life" by Stephen Jay Gould.  The big theme of all of Gould's
essays is the danger of confusing evolution with progress, and 
"Wonderful Life" is a good specific case example.

-Thomas C

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