The following letter appeared in 'Action and Reaction' in the October, 1993 issue of DISCO

The following letter appeared in "Action and Reaction" in the October, 1993
issue of DISCOVER magazine.

                           The Arrow of Evolution

    I was extremely pleased with Lori Oliwenstein's Evolution Watch, "Onward
and Upward?" in the June issue.  The concept of increasing complexity in
evolution has remained an intriguing area of research for many scientists, and
when I read your article I was impressed to see that DISCOVER took the time and
effort to give a more accurate picture.  Most schools throughout the nation
have consistently taught that evolution is an ongoing process toward perfection
of an organism or a species.  In truth, as Oliwenstein points out, many
biologists are finding that this is not always the case.  Numerous discoveries
reveal quite a different goal for this remarkable phenomenon.
    Evolution, especially through natural selection, is a process that enables
a species to survive better in an ecological setting.  This does not mean that
organisms must be more complex.  After all, the most abundant animals are
bacteria--simple organisms that nonetheless are able to thrive in any habitat.
As a result, scientists are uncovering a biological process that works
differently under different circumstances.  Evolution is not simply the "monkey
to man" image so frequently exhibited in high school texts but rather a complex
and unique mechanism that incorporates all the elements of nature.  In
evolution the potential for the species' survival is of crucial importance--and
more complexity may not be the result.
    I hope society discovers this irony of evolution.  In doing so, we will
learn more about ourselves and acquire a greater understanding of the world
around us.

                                        John Carvalho
                                        Biological and Chemical Sciences Dept.
                                        University of Dallas