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Darwin-L Message Log 1:137 (September 1993)

Academic Discussion on the History and Theory of the Historical Sciences

This is one message from the Archives of Darwin-L (1993–1997), a professional discussion group on the history and theory of the historical sciences.

Note: Additional publications on evolution and the historical sciences by the Darwin-L list owner are available on SSRN.


<1:137>From ronald@uhunix.uhcc.Hawaii.Edu  Wed Sep 15 20:50:31 1993

Date: Wed, 15 Sep 93 15:40:52 HST
From: Ron Amundson <ronald@uhunix.uhcc.Hawaii.Edu>
To: darwin-l@ukanaix.cc.ukans.edu
Subject: Re: Lamarkianism in linguistic change

> "Simpler" or "more specialized" must be estimated with respect to the
> moving target presented by the environment, or so I always thought...
>
> George
> ggale@vax1.umkc.edu

There are several sorts of comparative terms.  Some are relativized to
the environment; "specialized" indicates a derived change adapted to a
(relatively) small portion of the full environment.  Darwin's moth
with the 6" proboscis counts as specialized partly because few flowers
have their pollen stored 6" down a tube -- if all flowers did, then
the moth would not be "specialized".  Methane metabolizing bacteria
are adapted to a small part of the environment, but we would not call
them "specialized" because oxygen metabolizing bacteria descended from
them.  Oxygen metabolism might once have been a "specialized" trait --
until an oxygen rich atmosphere covered the planet).

"Primitive" is a term used sometimes by systematists as a synonym for
an ancestral condition of a certain trait.  It is misunderstood
popularly to mean simpler, or less "highly" evolved.  In this sense a
primitive trait may be simpler, more complex, more generalized, or
more specialized.  The comparisons are only between ancestral and
derived conditions of the trait, and the environment is not involved
in the definition.

While I'm generally skeptical about classifications of higher and
lower, there are some objective ones.  Complexity can be judged, for
example, by counting the number of distinct tissue types in a species.
Stuart Kauffman does this in The Origins of Order, and in a recent
Scientific American article.

Ron Amundson
ronald@uhunix.uhcc.hawaii.edu

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