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Darwin-L Message Log 28: 1–17 — December 1995

Academic Discussion on the History and Theory of the Historical Sciences

Darwin-L was an international discussion group on the history and theory of the historical sciences, active from 1993–1997. Darwin-L was established to promote the reintegration of a range of fields all of which are concerned with reconstructing the past from evidence in the present, and to encourage communication among scholars, scientists, and researchers in these fields. The group had more than 600 members from 35 countries, and produced a consistently high level of discussion over its several years of operation. Darwin-L was not restricted to evolutionary biology nor to the work of Charles Darwin, but instead addressed the entire range of historical sciences from an explicitly comparative perspective, including evolutionary biology, historical linguistics, textual transmission and stemmatics, historical geology, systematics and phylogeny, archeology, paleontology, cosmology, historical geography, historical anthropology, and related “palaetiological” fields.

This log contains public messages posted to the Darwin-L discussion group during December 1995. It has been lightly edited for format: message numbers have been added for ease of reference, message headers have been trimmed, some irregular lines have been reformatted, and error messages and personal messages accidentally posted to the group as a whole have been deleted. No genuine editorial changes have been made to the content of any of the posts. This log is provided for personal reference and research purposes only, and none of the material contained herein should be published or quoted without the permission of the original poster.

The master copy of this log is maintained in the Darwin-L Archives (rjohara.net/darwin) by Dr. Robert J. O’Hara. The Darwin-L Archives also contain additional information about the Darwin-L discussion group, the complete Today in the Historical Sciences calendar for every month of the year, a collection of recommended readings on the historical sciences, and an account of William Whewell’s concept of “palaetiology.”


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DARWIN-L MESSAGE LOG 28: 1-17 -- DECEMBER 1995
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DARWIN-L
A Network Discussion Group on the
History and Theory of the Historical Sciences

Darwin-L@ukanaix.cc.ukans.edu is an international network discussion group on
the history and theory of the historical sciences.  Darwin-L was established
in September 1993 to promote the reintegration of a range of fields all of
which are concerned with reconstructing the past from evidence in the present,
and to encourage communication among academic professionals in these fields.
Darwin-L is not restricted to evolutionary biology nor to the work of Charles
Darwin but instead addresses the entire range of historical sciences from an
interdisciplinary perspective, including evolutionary biology, historical
linguistics, textual transmission and stemmatics, historical geology,
systematics and phylogeny, archeology, paleontology, cosmology, historical
anthropology, historical geography, and related "palaetiological" fields.

This log contains public messages posted to Darwin-L during December 1995.
It has been lightly edited for format: message numbers have been added for ease
of reference, message headers have been trimmed, some irregular lines have been
reformatted, and some administrative messages and personal messages posted to
the group as a whole have been deleted.  No genuine editorial changes have been
made to the content of any of the posts.  This log is provided for personal
reference and research purposes only, and none of the material contained herein
should be published or quoted without the permission of the original poster.
The master copy of this log is maintained in the archives of Darwin-L by
listserv@ukanaix.cc.ukans.edu, and is also available on the Darwin-L Web Server
at http://rjohara.uncg.edu.  For instructions on how to retrieve copies of this
and other log files, and for additional information about Darwin-L, send the
e-mail message INFO DARWIN-L to listserv@ukanaix.cc.ukans.edu, or connect to
the Darwin-L Web Server.

Darwin-L is administered by Robert J. O'Hara (darwin@iris.uncg.edu), Center for
Critical Inquiry in the Liberal Arts and Department of Biology, University of
North Carolina at Greensboro, Greensboro, North Carolina 27412 U.S.A., and it
is supported by the Center for Critical Inquiry, University of North Carolina
at Greensboro, and the Department of History and the Academic Computing Center,
University of Kansas.

_______________________________________________________________________________

<28:1>From DARWIN@iris.uncg.edu Fri Dec  1 00:22:50 1995

Date: Fri, 01 Dec 1995 01:22:41 -0400 (EDT)
From: DARWIN@iris.uncg.edu
Subject: List onwer's monthly greeting
To: darwin-l@ukanaix.cc.ukans.edu
Organization: University of NC at Greensboro

Greetings to all Darwin-L subscribers.  On the first of every month I send
out a short note on the status of our group, along with a reminder of basic
commands.  For additional information about the group please visit the
Darwin-L Web Server (http://rjohara.uncg.edu).

Darwin-L is an international discussion group for professionals in the
historical sciences.  The group is not devoted to any particular discipline,
such as evolutionary biology, but rather seeks to promote interdisciplinary
comparisons across the entire range of "palaetiology".  Darwin-L currently
has more than 600 members from over 30 countries.

Because Darwin-L does have a large membership and is sometimes a high-volume
discussion group it is important for all participants to try to keep their
postings as substantive as possible so that we can maintain a favorable
"signal-to-noise" ratio.  Personal messages should be sent by private e-mail
rather than to the group as a whole.  Subscribers who feel burdened from
time to time by the volume of their Darwin-L mail may wish to take advantage
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Because different mail systems work differently, not all subscribers see
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The following are the most frequently used listserv commands that Darwin-L
members may wish to know.  All of these commands should be sent as regular
e-mail messages to the listserv address (listserv@ukanaix.cc.ukans.edu),
not to the address of the group as a whole (Darwin-L@ukanaix.cc.ukans.edu).
In each case leave the subject line of the message blank and include no
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program rather than by a person.  To join the group send the message:

     SUBSCRIBE DARWIN-L Your Name

     For example: SUBSCRIBE DARWIN-L John Smith

To cancel your subscription send the message:

     UNSUBSCRIBE DARWIN-L

If you feel burdened by the volume of mail you receive from Darwin-L you
may instruct the listserv program to deliver mail to you in digest format
(one message per day consisting of the whole day's posts bundled together).
To receive your mail in digest format send the message:

     SET DARWIN-L MAIL DIGEST

To change your subscription from digest format back to one-at-a-time
delivery send the message:

     SET DARWIN-L MAIL ACK

To temporarily suspend mail delivery (when you go on vacation, for example)
send the message:

     SET DARWIN-L MAIL POSTPONE

To resume regular delivery send either the DIGEST or ACK messages above.

For a comprehensive introduction to Darwin-L with notes on our scope and
on network etiquette, and a summary of all available commands, send the
message:

     INFO DARWIN-L

To post a public message to the group as a whole simply send it as regular
e-mail to the group's address (Darwin-L@ukanaix.cc.ukans.edu).

I thank you all for your continuing interest in Darwin-L and in the
interdisciplinary study of the historical sciences.

Bob O'Hara, Darwin-L list owner

Robert J. O'Hara (darwin@iris.uncg.edu)
Center for Critical Inquiry in the Liberal Arts and Department of Biology
100 Foust Building, University of North Carolina at Greensboro
Greensboro, North Carolina 27412 U.S.A.

_______________________________________________________________________________

<28:2>From rroizen@ix.netcom.com Fri Dec  1 10:29:34 1995

Date: Fri, 1 Dec 1995 08:28:27 -0800
From: rroizen@ix.netcom.com (Ron Roizen )
Subject: Darwin Letter in Today's NY Times
To: DARWIN-L@ukanaix.cc.ukans.edu

Following letter appeared in the NY Times today (12/1/95, p. A14).  The
title line read:  "What the Mockingbirds Taught Darwin."  Incidentally,
the letter is graced with a whimsical line drawing of a curious Darwin
peering at a bird on flat ground through a monocle.  Ron Roizen

To the Editor:
     A Nov. 28 article on the Galapagos Islands summarizes the
political crisis that has placed their ecological integrity at risk.
The article, unfortunately, perpetuates myths about Darwin's
experiences in Galapagos.  Not only are there fewere than "39 kinds of
finches" in the archipelago (thee are 13 species), but also Darwin
observed only 6 species druning his brief stay (on four islands) in
1835 -- including 2 that he did not even recognize as finches!
     That the Galapagos finches were not critical in the development of
"Origin of Species" is clear:  Darwin did not mention these birds in
the first edition, though he came to appreciate their relevance in
later editions and in his published journal.
     In contrast, the island's native mockingbirds had a profound
influence on Darwin's thinking.  His realization that the three species
he encountered differed among nearby islands represents the first and
most significant step motivating Darwin to search for a cheanism
capable of producing such differences.
     The finches exhibit a pattern of adaptive radiation
(differentiation) consistent with Darwin's methanism (natural
selection), but this conclusion came late to Darwin and was not fleshed
out until this century in studies by biologists like David Lack, Robert
Bowman and Peter and Rosemary Grant.
Robert L. Curry
Assistant Professor of Biology
Villanova University
Villanova, Pa., Nov. 28, 1995

_______________________________________________________________________________

<28:3>From g-cziko@uiuc.edu Sat Dec  2 21:59:11 1995

Date: Sat, 2 Dec 1995 21:59:22 -0600
To: darwin-l@ukanaix.cc.ukans.edu
From: g-cziko@uiuc.edu (CZIKO Gary)
Subject: Time Magazine on "Supersonic Evolution"

[from Gary Cziko <g-cziko@uiuc.edu>]

It's been mighty quiet on Darwin-L lately.  So I suppose it's time to stir
up some more trouble.

Waiting in the supermarket checkout line, I couldn't resist picking up a
copy of the December 4 Time Magazine when I saw on its cover in big yellow
letters "EVOLUTION'S BIG BANG."  I first thought that it must have been a
slow week for big news stories.  But then I realized that evolution IS news
to most Americans.

Here are some selected quotes from the magazine cover and cover story (with
EMPHASES added):

*********************************************************

"New discoveries show that life as we know it began in an amazing
biological frenzy that changed the planet ALMOST OVERNIGHT." (front cover)

"For billions of years, simple creatures like plankton, bacteria and algae
ruled the earth.  Then SUDDENLY, life got very complicated." (article
lead-in, p. 67)

" . . . creatures with teeth and tentacles and claws and jaws materialized
WITH THE SUDDENNESS OF APPARITIONS." (p. 68)

" . . . the period of biological innovation occurred AT VIRTUALLY THE SAME
INSTANT in geologic time all around the world." (p. 68)

"EVOLVING AT SUPERSONIC SPEED" (section title, p. 70)

BEYOND DARWINISM (section title, p. 73)

"'What Darwin described in the _Origin of Species_,' observes Queen's
University paleontologist Narbonne, 'was the steady background kind of
evolution.  But there also seems to be a non-Darwinian kind of evolution
that functions over extremely short time periods--and that's where all the
action is.'" (p. 74)

"'We now know how fast fast is,' grins [MIT's Samuel] Bowring.  'And what I
like to ask my biologist friends is, How fast can evolution get before they
start feeling uncomfortable?'" (p. 70)

*********************************

Even though I am no biologist, I must admit that I am getting pretty
uncomfortable, with terms like "almost overnight," "instant," "supersonic
speed", and "suddenness of apparitions" being used to describe evolution.
Darwin (and my universal selection theory) is in BIG TROUBLE if dramatic
increases in adapted complexity evolved almost overnight at supersonic
speed.

I hope that some of the biologists on the list can clue me on how this can
all happen so fast without miracles using "non-Darwinian evolution."  If
they can't, I suppose I will have to go back to my prior belief in a Grand
Designer who takes it easy most of the time but who put in a hell of a lot
of work one night about 500 million years ago.

--Gary Cziko

P.S.  It's interesting that people like Dawkins and Maynard Smith and
Dennett (OK, I realize that Dennett is just a philosopher) were not
mentioned in the article, while Gould was.  But that's probably because the
former three keep harping on the old-fashioned Darwinian stuff which is not
"where all the action is."

P.P.S.  There are some great illustrations in the article.  The "burst of
creativity" one on pages 70-71 is one of the best I've seen (despite it's
name) for giving an overview of the time scale of life on earth.

-------------------------------------------------------------------
Gary Cziko
Associate Professor              Telephone 217-333-8527
Educational Psychology           FAX: 217-244-7620
University of Illinois           E-mail: g-cziko@uiuc.edu
1310 S. Sixth Street             Radio: N9MJZ
210 Education Building
Champaign, Illinois 61820-6990

http://www.uiuc.edu/ph/www/g-cziko/
-------------------------------------------------------------------

_______________________________________________________________________________

<28:4>From Agoldenk@aol.com Sun Dec  3 11:12:07 1995

Date: Sun, 3 Dec 1995 12:12:03 -0500
From: Agoldenk@aol.com
To: darwin-l@ukanaix.cc.ukans.edu
Subject: Re: Time Magazine on "Supersonic Evolution"

Well, an interesting article it was. . .

Only Time, or some other popular journal concerned more with selling paper
rather than accuracy, could confuse 20 to 30 million years with "overnight".

There may be room for more than one bush or tree (see David Deamer's work on
cell membrane formation happing in several places at once), but I read
nothing that completely shakes the theory.  Modifies, yes.  The rate and
units of selection are open issues as far as I'm concerned.

_______________________________________________________________________________

<28:5>From elanier@crl.nmsu.edu Sun Dec  3 15:57:59 1995

Date: Sun, 3 Dec 1995 14:57:53 -0700
To: darwin-l@ukanaix.cc.ukans.edu
From: elanier@crl.nmsu.edu (Ellery Lanier)
Subject: supersonic speed

We are all indebted to Gary for having made the evolutionary leap so easy
for us.

His listing of selected quotes finally bridges the gap between fine
literature and fine science. I believe the Time copy people must take
lessons from the Witnesses. Almost as much fun.

ALMOST OVERNIGHT
SUDDENLY
WITH THE SUDDENNESS OF APPARITIONS
AT VIRTUALLY THE SAME INSTANT
EVOLVING AT SUPERSONIC SPEED
BEYOND DARWINISM
that's where all the action is.

Such onomatopoeia! (spelling?) and I thought I understood Darwin! Give the
Time writers a cigar.

Thank you Gary, you made my sunday afternoon.

ellery

_______________________________________________________________________________

<28:6>From KOLB@ucla.edu Sun Dec  3 17:25:13 1995

Date: Sun, 3 Dec 1995 15:08:36 -0800
To: darwin-l@ukanaix.cc.ukans.edu
From: Jack Kolb <KOLB@ucla.edu>
Subject: Re: Time Magazine on "Supersonic Evolution"

Gary's post provides me (a decided non-scientist: be gentle, please {grin})
with an opportunity to pose another potential topic of discussion: an
article in the October issue of _Discover_ magazine about the theory of
Hypersea (the biological linkage of life on earth [vs. life in the oceans]).
I'll try to elaborate if anyone cares.  I found it utterly fascinating, but
obviously don't know enough to judge its soundness.  Jack.

kolb@ucla.edu

_______________________________________________________________________________

<28:7>From BENEDICT@VAX.CS.HSCSYR.EDU Mon Dec  4 11:11:33 1995

Date: Mon, 04 Dec 1995 12:10:32 -0500 (EST)
From: BENEDICT@VAX.CS.HSCSYR.EDU
Subject: Re: Time Magazine on "Supersonic Evolution"
To: darwin-l@ukanaix.cc.ukans.edu

In defense of Time, you need to do a little math here. Life has been around
for about 3X10^9 years and the period discussed is about 3X10^7 years long, so
all this appears to have happened in about 1/100th of the period living things
have been around. That sounds pretty "overnight" to me. On the other hand it
took about 2.5X10^9 years to evolve the cellular and genetic machinery needed
to permit this evolutionary explosion, and most of those changes didn't have a
big effect on the outward appearance of living creatures until about 0.6X10^9
years ago. But remember, that's more than 80% of the time life has been
around, and the number gets worse the older you assume that life first
appeared, so maybe it isn't so amazing after all.
  But those were really great drawings...

Paul DeBenedictis
SUNY Health Science Center at Syracuse

_______________________________________________________________________________

<28:8>From mwinsor@epas.utoronto.ca Mon Dec  4 10:47:41 1995

From: Mary P Winsor <mwinsor@epas.utoronto.ca>
Subject: multiplying elephants
To: darwin-l@ukanaix.cc.ukans.edu (bulletin board)
Date: Mon, 4 Dec 1995 11:47:15 -0500 (EST)

     I am using John Moore's <Science as a Way of Knowing: the Foundations
of Modern Biology> (Harvard U.P. 1993) for an undergraduate course, and I
often find myself writing little notes to my students, quarreling with him.
For example, on p. 161-2, Moore quotes Darwin's "There is no exception to
the rule that every organic being naturally increases at so high a rate, that
if not destroyed, the earth would soon be covered by the progeny of a single
pair."  Assuming a pair of elephants brings forth 6 young, Darwin calculates
that "at the end of the fifth century there would be alive fifteen million
elephants, desended from the first pair."  Moore then says,

     "Yet in all likelihood, an average original pair would have only two
surviving offspring - 14,999,998 would have perished. The struggle for
existence is a tremendously impressive fact of nature."

To this I reply,
     Moore is quite wrong to conclude that Darwin's application of Malthusian
reasoning tells us that 14,999,998 elephants must perish in the five centuries
of Darwin's thought experiment.  The point for both Malthus and Darwin is the
contrast between a calculated geometric population growth that could
theoretically occur on the one hand, and on the other hand the roughly
constant levels at which populations actually maintain themselves.  Potential
for geometric increase does not require a high rate of fertility, but is
present for any organism whose lifetime fertility is greater than one.  Darwin
imagines an elephant having only 6 baby elephants in all her 60 fertile years,
and he calculates that in less than 500 years (in fact, in 14 generations)
her offspring will number 15 million.  In this thought experiment, no young
elephants ever perish; all elephants grow to adulthood, raise offspring, and
die of old age.  If now we wish to switch to a more realistic scenario, where
a pair of elephants leaves only two surviving offspring, we must admit that
somehow the four other babies perished.  Continuing the thought experiment,
where the population is not growing, we can tally four perishing young
elephants per mother in each generation.  Over the 14 generations of Darwin's
experiment, that is only 56 superfluous offspring.  The millions of the first
thought experiment never come into existence in the second, more realistic,
thought experiment.
     The Malthusian principle of population pressure does not wait lurking,
only to take effect by killing off superfluous elephants at the end.  It
operates all the time, preventing the potential increase from occuring.
     It is also misleading for Moore to say "in all likelihood, an average
original pair would have only two surviving offspring" [after the 14
generations].  By definition, a statistically typical mother of the first
generation would have left in the final generation one many-greats-grand-
daughter, but here is where statistics are misleading.  They key to Darwin's
theory lies in the fact that "in all likelihood," some of the original
elephants could have left many more than their share of descendants after 14
generations, indeed one elephant could have generated millions, while other
elephants experienced the dark side of the law of averages, and will have
left no descendant at all.  In all likelihood, the average is not typical.
     Polly Winsor    mwinsor@epas.utoronto.ca

P.S. Bob O'Hara points out to me that one of Darwin's readers in 1869
recognized there were some problems with exactly how many elephants would be
alive after exactly how many centuries, and Darwin agreed, but the precise
number is not relevant to the point I make here.  (Darwin Origin of Species,
facsimile p. 64; Collected Papers of CD ed. Paul H. Barrett, pp.156-7)

_______________________________________________________________________________

<28:9>From ahouse@hydra.rose.brandeis.edu Tue Dec  5 09:42:04 1995

Date: Tue, 5 Dec 1995 10:41:57 -0500
To: Darwin-L@ukanaix.cc.ukans.edu (Darwin List)
From: ahouse@hydra.rose.brandeis.edu (Jeremy C. Ahouse)
Subject: Darwin: the last(?) portrait

FYI: a newly discovered portrait of Charles Darwin:

        Milner, Richard (1995) "Charles Darwin: the Last Portrait"
Scientific American. November, pg 78-79.

_______________________________________________________________________________

<28:10>From ahouse@hydra.rose.brandeis.edu Tue Dec  5 09:51:39 1995

Date: Tue, 5 Dec 1995 10:51:35 -0500
To: Darwin-L@ukanaix.cc.ukans.edu (Darwin List)
From: ahouse@hydra.rose.brandeis.edu (Jeremy C. Ahouse)
Subject: Re: Time Magazine

If you are interested in reading the actual article from Time

Nash, J. Madeleine (1995) "When Life Exploded" Time. v146 n23. 4 December
p66-74 is available on the web:

http://pathfinder.com/@@xVbMYcGrwAAAQDZi/time/magazine/
domestic/1995/951204/cover.html

        - Jeremy

        Jeremy C. Ahouse
        Biology Department
        Brandeis University
        Waltham, MA 02254-9110
ph:     (617) 736-4954
fax:    (617) 736-2405
email:  ahouse@hydra.rose.brandeis.edu

        "I am a carnivorous fish swimming in two waters, the cold water of
art and the hot water of science." -Salvador Dali

_______________________________________________________________________________

<28:11>From charlie_urbanowicz@macgate.csuchico.edu Tue Dec  5 12:18:55 1995

Date: 5 Dec 1995 10:13:57 U
From: "Charlie Urbanowicz" <charlie_urbanowicz@macgate.csuchico.edu>
Subject: TIME MAGAZINE
To: darwin-l@ukanaix.cc.ukans.edu

Many probably already know this, but just in case:  the text of the TIME
article is available from TIME @

http://pathfinder.com/@@945*k1HllQAAQEhi/time/magazine/domestic/1995
/951204/cover.html

BUT, you might wish to start @ the TIME-WARNER Home Page:

http://pathfinder.com [and actually go to
http://pathfinder.com/@@*3nPDHGVkgAAQEli/time/universe.html
for "Back Issues" of TIME.

Charlie Urbanowicz
[curbanowicz@oavax.csuchico.edu]

_______________________________________________________________________________

<28:12>From hurd@bethel.edu Tue Dec  5 13:36:09 1995

Date: Tue, 5 Dec 95 14:54:31 CST
From: "James Hurd" <hurd@bethel.edu>
To: darwin-l@ukanaix.cc.ukans.edu
Subject: Re: New book on evolutionary biology

Introducing a new book:

INVESTIGATING THE BIOLOGICAL FOUNDATIONS
OF HUMAN MORALITY:  An Interdisciplinary Perspective.
Edited by James P. Hurd

The central question of this volume is: To what extent is evolutionary
biology a necessary and sufficient explanation for human morality?
Biologists, psychologists, anthropologists, theologians, and philosophers
address this question from their respective disciplines. Four main issues
are addressed:
-- Is human moral behavior unique? To what extent can it be explained using
models of animal behavior?
-- Does biology provide us only with a DEscription of how morality has
evolved or can it also provide us with a PREscription for what morality
should be? If the latter, do we seek to prescribe moral behavior as that
behavior which our biology has programmed, or is morality a culturally-
designed resistance to our biological propensities?
-- Can morality be adequately explained by a demonstration of natural
selection operating at the individual level, or are we forced to consider
natural selection operating at the level of the group or species?
-- To what extent can humans make autonomous moral choices (i.e., choices
not predetermined by biology or environment)?
This volume will interest scholars, students, and academic libraries in the
areas of sociobiology, ethics, religion, and social philosophy. It will
serve as a text for courses in ethics or sociobiology at the graduate
level and as a supplementary text for courses in ethics, philosophy,
psychology or anthropology at the undergraduate level.

Available from: Edwin Mellen Press, P.O. Box 450; Lewiston, New York  14092.
Telephone:  716 754-2266. ISBN:  0-7734-8843-x  264 pp. Textbook price:
$29.95 (five or more copies).

_______________________________________________________________________________

<28:13>From ahouse@hydra.rose.brandeis.edu Wed Dec  6 07:50:37 1995

Date: Wed, 6 Dec 1995 08:50:33 -0500
To: Darwin-L@ukanaix.cc.ukans.edu (Darwin List)
From: ahouse@hydra.rose.brandeis.edu (Jeremy C. Ahouse)
Subject: Kanzi: The Ape

        There is a Review of Savage-Rumbaugh and Lewin's "Kanzi: The Ape
..." by John Mitani from SCIENTIFIC AMERICAN, June 1995, Volume 272 Number
6 available on the web http://envirolink.org/arrs/essays/kanzi_review.html

        - Jeremy

        Jeremy C. Ahouse
        Biology Department
        Brandeis University
        Waltham, MA 02254-9110
ph:     (617) 736-4954
fax:    (617) 736-2405
email:  ahouse@hydra.rose.brandeis.edu

        "I am a carnivorous fish swimming in two waters, the cold water of
art and the hot water of science." -Salvador Dali

_______________________________________________________________________________

<28:14>From g-cziko@uiuc.edu Wed Dec  6 09:05:39 1995

Date: Wed, 6 Dec 1995 09:06:37 -0600
To: darwin-l@ukanaix.cc.ukans.edu
From: g-cziko@uiuc.edu (CZIKO Gary)
Subject: Fast Evolution: Do We Need a Miracle?

[from Gary Cziko <g-cziko@uiuc.edu>

Thanks to Charlie Urbanowicz and Jeremy Ahouse for pointing out how to get
the TIME article on evolution on the web.  This makes it much easier to
refer to.

Here is the part I find particularly interesting:

"""""""""""""""""""""""""""""""""""""""""""""""""""""

EVOLVING AT SUPERSONIC SPEED

Scientists used to think that the evolution of phyla took place over a period
of 75 million years, and even that seemed impossibly short. Then two years
ago, a group of researchers led by Grotzinger, Samuel Bowring from M.I.T.
and Harvard's Knoll took this long-standing problem and escalated it into a
crisis. First they recalibrated the geological clock, chopping the Cambrian
period to about half its former length. Then they announced that the interval
of major evolutionary innovation did not span the entire 30 million years,
but rather was concentrated in the first third. "Fast," Harvard's Gould
observes, "is now a lot faster than we thought, and that's extraordinarily
interesting."

"""""""""""""""""""""""""""""""""""""""""""""""""""""
So if the initial of estimate of 75 million years is "impossibly short" for
the evolution of phyla, then the current estimate of 10 million must be
downright miraculous.  But is it?

10 million still seems like a very long time to me, but then again I am
still rather young (as least by these standards).  If we went back to the
Cambrian in a time machine to observe what was going on, would we even
notice anything happening during this "explosion" of life?  What would be
the generational time of these organisms that were evolving into different
phyla?  How many generations would there be in just 10 million years?

I hope that some biologists can answer these questions.  It would be
wonderful if this time span really was impossibly short for the phyla to
evolve using old-fashioned stupid, slow and gradual Darwinian selection,
since then I would finally be able to reject universal selection theory for
something better.  Perhaps miracles is "where the action is" after all.

--Gary Cziko

-------------------------------------------------------------------
Gary Cziko
Associate Professor              Telephone 217-333-8527
Educational Psychology           FAX: 217-244-7620
University of Illinois           E-mail: g-cziko@uiuc.edu
1310 S. Sixth Street             Radio: N9MJZ
210 Education Building
Champaign, Illinois 61820-6990

http://www.uiuc.edu/ph/www/g-cziko/
-------------------------------------------------------------------

_______________________________________________________________________________

<28:15>From ncse@crl.com Wed Dec  6 17:11:51 1995

Date: Wed, 6 Dec 1995 14:56:20 -0800 (PST)
From: "Eugenie C. Scott" <ncse@crl.com>
To: darwin-l@ukanaix.cc.ukans.edu
Subject: Re: New book on evolutionary biology

Another book on the same topic is *Created from Animals, the Moral
Implications of Darwinism* by philosopher James Rachels.

ECS

_______________________________________________________________________________

<28:16>From ahouse@hydra.rose.brandeis.edu Thu Dec  7 10:34:01 1995

Date: Thu, 7 Dec 1995 11:33:56 -0500
To: Darwin-L@ukanaix.cc.ukans.edu (Darwin List)
From: ahouse@hydra.rose.brandeis.edu (Jeremy C. Ahouse)
Subject: Dennett Ch.10 review (2/2)

        It trivializes the breadth of Gould's Burgess Shale book to focus
on two conclusions.  But let's push ahead with Dennett as he focuses on
contingency and disparity.  Contingency he takes as obvious and not worth
raising... implying that Gould is trading in trivialities.  You will have
to decide if Gould's compilation of progressivist human (male) centric
iconography justifies making this point to the audience that would be
interested in this book.  The second question is; how do we measure and
assess the direction of morphological change through time?  And when we
unpack this; what are the dynamics of variation in the lineages in the tree
of life?  Mark Ridley in his review complained that Gould has energized
this argument with a mistaken criterion; the use of higher taxonomic
categories (Ridley 1990).  I agree with the point that Ridley has to make.
This problem in systematics (what, if anything do grade based higher level
taxa mean) is still open.  Gould claims to have other criteria (Gould 1991)
including raising points about cladograms that use a large number of
loss-of-feature character state transitions.  In doing so he implicitly
raises the thorny issue of character weighting in a cladistic framework.
Both sides of this debate are worth spending time with (Gould 1993; McShea
1993; Ridley 1993).  Get yourself a copy of the wonderful coffee table book
on the Burgess (just out in paper Briggs, Erwin et al. 1994) and see how
you would classify this fauna.  Dennett does not address this important
issue.

        He does however hammer away at contingency (which, remember, he
thinks is a trivial point); "evolution can be an algorithm, and evolution
can have produced us by an algorithmic process, without it being true that
evolution is an algorithm for producing us" (pg. 308 Dennett 1995).  If you
are attracted to his use of the word algorithm to mean process then once
again he is falling into line with Gould although you wouldn't sense that
from the tone.  I think it falls to Dennett to show that the lay audience
for Gould's books have all long ago rejected any teleological leanings and
so don't need to be reminded that humans are not the point of the
narrative... even more challenging is that there is no narrative in the
traditional sense.  This is what Gould, who knows how to tell a good story,
must grapple with.  How do you deliver in an engaging way the message that
there is no simple narrative, no simple moral to be drawn from the history
of life?

        Ironically Gould and Dennett share the desire to remove the comfort
of the idea that the world exists solely for us and that humans are the
inevitable result of evolution.  Though (contra Gould) Dennett may be
arguing that some kind of sentience is inevitable.  In making the case
against teleology Gould insinuates these ideas more gently, without
insisting that his religious colleagues are lazy and dishonest; compare
"those evolutionists who see no conflict between evolution and their
religious beliefs have been careful not to look as closely as we have been
looking, or else hold a religious view that gives God what might we call a
merely ceremonial role to play" (pg. 310 Dennett 1995).  The symbolic and
mystical traditions that humans use to find personal (and importantly,
social) identity and meaning shouldn't be so summarily dismissed.

        It is important to recognize that some of Gould's distinctions were
intended as therapeutic, designed to pull people from careless habits.
Dennett in firm possession of a pristine adaptationism (8) would not
formally make any of these mistakes and so may not need the correctives.
But he has yet to demonstrate that the larger population of biologists (or
Gould's lay audience) had nothing to gain from spandrels, stasis, or
contingency.

        What drives Dennett's narrative?  One possibility was offered to me
at a seminar.  I wondered aloud who this book was for.  A computer
scientist suggested that maybe it was for the Alife crowd.  They enjoy the
assumption that the "evolution" that is seen in simulations is deeply
representative of what has happened on this planet.  This position is much
easier to sustain if you strip all the bothersome (intricate) details out
of the biological picture and synonymize evolution with a simple
selectionism.

        Mark Ridley's review of "Darwin's Dangerous Idea" (Ridley 1995)
makes the point that while "natural selection arguably is the universal
explanation for biological adaptation, it is not for evolution."  This
raises the possibility that Dennett is really more of a Spencerian,
enthusiastic about selectionist models and ready to use them whenever and
wherever he can?  While I share his enthusiasm for the wonderful
possibilities that natural selection suggests, the strident and self
righteous tone of "Dangerous Idea" will leave this book only the audience
of the converted, and they would probably prefer something more nuanced and
careful (e.g. Keller and Lloyd 1992; Sober 1994).  I don't want to blunt
Dennett's enthusiasm for evolutionary biology - champions are to be prized.
Though I fear that his enthusiasm is for selectionist theories not for
explaining the distribution and abundance of living forms, and this induces
him to walk in with a bit too much baggage, he "knows" too much.  "The
action of thought is excited by the initiation of doubt, and ceases when
belief is attained..." (Peirce 1932). Maybe we can make a place safe enough
for him to put some of those bags down and luxuriate in the intricacies of
the biological world and let a little doubt shine in.

____

        Thank you to the list for all the encouragement, please comment
heartily.  Thank you also to Ron Amundson, Hugh Pendleton, Craig Story,
Gary Cziko, and John Barthel for various levels of comment and sparring.
____

(1) It remains a possibility that 'space' (design or morpho) is just
Dennett's way of discussing a point set and that there is no need to have
any sense of distance (a metric).  I think that this move looses an
interesting and important intuition.

(2) Genetic algorithms (a current vogue in computer science) are used
"experimentally" not analytically to solve particular problems.  This area
is full of questions about how a problem is to be encoded and how the
solution landscape is related to the "genetic" operators that are used in
the simulation.  To get a sense of what is currently happening in the alife
community visit http://www.krl.caltech.edu/~brown/alife/,
http://alife.santafe.edu:80/~joke/zooland/, or
http://alife.santafe.edu:80/alife/.

        It has been suggested to me that I am not charitable enough to a
possible metaphorical reading of algorithm (i.e. that Dennett's use of
algorithm is looser and does not entail all that it would technically
entail).  I will resist granting this (unless Dennett expressly asks for
this kind of release) because he seems to trade on our enthusiasm for
guaranteed results from algorithms to say that Natural Selection carries a
guarantee.

(3) "At the beginning you achieve success if you are interesting to a
growing audience.  If nonexperts at your game begin to use it
metaphorically,  leading to other interesting conversations, you have
success-two.  If you get beyond this stage, make a research project out of
determining criteria for success." (Pendleton 1995)

(4) While there are certainly still creationists in American society and
there are many people who know very little about the distribution and
abundance of living forms and so don't feel that they need a theory of
evolution to explain the world that they see around themselves.  But
Dennett isn't weighing in on that debate.  Is Dennett claiming that Gould's
discussion of the adaptationist program, punctuated equilibrium, the
Burgess Shale, etc... is a critical part of the armamentarium of
creationists?

(5) Studying proteins is a dizzying exercise in the complexities of
function assignment.  This is readily seen after a particular function has
been identified (e.g. the fibroblast growth factor receptor) and then it
turns out that you can find that molecule interacting with other things
than you had imagined when it was named (e.g. novel ligands for the FGF
receptor Kinoshita, Minshull et al. 1995).

(6) The paralogy and orthology distinction was introduced 25 years ago to
distinguish two kinds of homology in proteins (Fitch 1970).  While
orthology has the traditional meaning of morphological homology, paralogy
is meant to cover those situations when a gene duplication allows related
proteins to evolve independently within the same linneage.  Orthologs are
found in different individuals and paralogs can be found in the same
individual.  These and other important issues in protein evolution are
reviewed in the introduction to the proceedings of the Third International
Congress of Systematics and  Evolutionary Biology (Patterson 1987).

(7)  You can find a review of punk eek (Prothero 1992) on the net;
http://www.skeptic.com/01.3.prothero-punc-eq.html.

(8) As I read Dennett I get the sense that he believes that biologists long
for a kind of crystal palace of perfect adaptationism.  In a previous post
I referred to this palace as vapid selectionism.  I meant that rather
literally.  My American Heritage dictionary offers; lacking taste, zest,
flavor: vapid beer.  This is what I wanted to capture.  The biologists I
know glory in the exquisite mix of contingency, adaptation and constraint
that is in evidence in the uncountable compromises that result in a
particular ecosystem on a particular day resulting in (to emphasize the
contrast) an epicurean selectionism.
____

Adams, D. (1988). The Long Dark Tea-Time of the Soul. New York, Simon and
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Ahouse, J. J., J. Hagerman, et al. (1993). "Mouse MHC Class I-like Fc
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Cormen, T. H., C. E. Leiserson, et al. (1990). Introduction to Algorithms.
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Dennett, D. C. (1995). Darwin's dangerous idea: evolution and the meanings
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Fleagle, J. G. (1988). Primate adaptation and evolution, Academic Press.

Fontana, W., G. Wagner, et al. (1994). "Beyond Digital Naturalism."
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Gottlieb, A. (1995). "We are all cousins: Darwin's Dangerous Idea." The
Spectator 275(8724) 23 September: 34-36.

Gould, S. J. (1977). Darwin's Untimely Burial. Ever Since Darwin. NY, Norton.

Gould, S. J. (1989). Wonderful Life: The Burgess Shale and the Nature of
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Gould, S. J. (1991). "The disparity of the Burgess Shale arthropod fauna
and the limists of cladistic analysis: why we must strive to quantify
morphospace." Paleobiology 17(4): 411-423.

Gould, S. J. (1992). "The confusion over evolution." New York Review of
Books 19 November: 47-54.

Gould, S. J. (1993). "Confusion over evolution: an exchange." New York
Review of Books 14 January: 44.

Gould, S. J. (1993). "How to analyze the Burgess Shale disparity - a reply
to Ridley." Paleobiology 19(4): 522-523.

Gould, S. J. (1994). "Common Pathways of Illumination: Humans and squid may
literally look at things the same way." Natural History(December): 10-20.

Gould, S. J. (1994). "Tempo and mode in macroevolutionary reconstruction of
Darwinism." PNAS 91: 6764-6771.

Gould, S. J. and N. Eldredge (1993). "Punctuated Equilibrium comes of age."
Nature 366: 223-227.

Gould, S. J. and R. C. Lewontin (1979). "The spandrels of San Marco and the
Panglossian Paradigm: a critique of the adaptationist programme."
Proceedings of the Royal Society of London B 205: 581-598.

Gould, S. J. and E. S. Vrba (1982). "Exaptation - a missing term in the
science of form." Paleobiology 8: 4-15.

Gray, R. (1992). Death of the Gene: Developmental Systems Strike Back.
Trees of Life. P. Griffiths. Netherlands, Kluwer Academic: 165-209.

Halder, G., P. Callaerts, et al. (1995). "New perspectives on eye
evolution." Current opinion in Genetics & Development 5: 602-609.

Holt, J. (1995). "Bookshelf: Wholly DNA: Defending natural selection." The
Wall Street Journal 4 August: 6 (sec. A).

Kandil, E., M. Noguchi, et al. (1995). "Structural and Phylogenetic
Analysis of the MHC Class I-Like Fc Receptor Gene." Journal of Immunology
154: 5907-5918.

Keller, E. F. and E. A. Lloyd, Eds. (1992). Keywords in Evolutionary
Biology. Cambridge, MA, Harvard University Press.

Kinoshita, N., J. Minshull, et al. (1995). "The Identification of Two Novel
Ligands of the FGF Receptor by a Yeast Screening Method and Their Activity
in XenopusDevelopment." Cell 83(17): 621-630.

Lewin, R. (1995). "Disrobing the Naked Ape." Los Angeles Times 14 May: 3
(sec BR).

Lufkin, T., M. Mark, et al. (1992). "A Homeotic Transformation of the
Occipital Bones of the skull by ectopic expression of a homeobox gene."
Nature 359(6398): 835-841.

Masters, J. (1995). "The Rules of the Game." Book World 16 July: 8.

Maynard-Smith, J. (1995). "Genes, Memes, & Minds." New York Review of Books
30 November: 46-48.

McShea, D. W. (1993). "Arguments, tests, and the Burgess Shale - a
commentary on the debate." Paleobiology 19(4): 399-402.

Murphy, E. A. (1979). "Quantitative Genetics: A Critique." Social Biology
26(2): 126-141.

Nijhout, H. F. (1990). "Metaphors and the role of genes in development."
Bioessays 12: 441-446.

Papineau, D. (1995). "Natural Selections." The New York Times Book Review
14 May: 13 (sec 7).

Patterson, C. (1987). Introduction. Molecules and morphology in evolution:
conflict or compromise? C. Patterson. Cambridge, Cambridge University
Press.

Peirce, C. S. (1932). Collected Papers. Cambridge, MA, Harvard University
Press: 2.113.

Pendleton, H. (1995). personal communication.

Pollock, R. A., S. Tadru, et al. (1995). "Gain of function mutations for
paralogous Hox genes: Implications for the evolution of Hox gene function."
Proceedings of the National Academy of Sciences of the United States of
America 92: 4492-4496.

Prothero, D. R. (1992). "Punctuated Equilibrium at Twenty: a
Paleontological Perspective." Skeptic 1(3): 38-47.

Quiring, R., U. Walldorf, et al. (1994). "Homology of the Eyeless gene of
Drosophila to the Small Eye Gene in Mice and Aniridia in Humans." Science
265(5173): 785-789.

Raup, D. and J. J. Sepkoski (1982). "Mass Extinction in the Marine Fossil
Record." Science 215(19 March): 1501-1503.

Ray, T. S. (1994). "An Evolutionary Approach to Synthetic Biology: Zen and
the Art of Creating Life." Artificial Life 1: 179-209.

Ridley, M. (1990). "Dreadful Beasts: a review of Wonderful Life by Stephen
Jay Gould." The London Review of Books(28 June): 11-12.

Ridley, M. (1993). "Analysis of the Burgess Shale." Paleobiology 19(4): 519-521.

Ridley, M. (1995). "Here, there, everywhere." Nature 375(6531): 457-458.

Rorty, R. (1995). "Cranes and Skyhooks." Lingua Franca(July/August) : 62-65.

Salvini-Plawen, L. and E. Mayr (1977). "On the evolution of photoreceptors
and eyes." Evolutionary Biology 10: 207-263.

Sober, E., Ed. (1994). Conceptual Issues in Evolutionary Biology.
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Weigel, D. and E. M. Meyerowitz (1994). "The ABCs of Floral Homeotic
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_______________________________________________________________________________

<28:17>From ahouse@hydra.rose.brandeis.edu Thu Dec  7 10:33:11 1995

Date: Thu, 7 Dec 1995 11:32:57 -0500
To: Darwin-L@ukanaix.cc.ukans.edu (Darwin List)
From: ahouse@hydra.rose.brandeis.edu (Jeremy C. Ahouse)
Subject: Dennett Ch.10 review (1/2)

        "For about a minute Dirk remained sitting motionless in his car a
few yards away from his front door.  He wondered what his next move should
be.  A small, cautious one, he rather thought.  The last thing he wanted to
have to contend with at the moment was a startled eagle." (pg. 211 Adams
1988)

        Over the last couple of months there has been some discussion of
Daniel Dennett's characterization of Stephen Jay Gould as someone longing
for miraculous explanations, out of touch with Darwinian explanations, and
trying to push a political not a scientific agenda (ch. 10 Dennett 1995).
These conclusions were clearly chosen for their rhetorical punch and by
themselves might be enough to dismiss Dennett's project.  I have said as
much on this list and have tracked the reviews of Dennett's book waiting
for someone to resist his contentious style and empirically unencumbered
arguments.

        I recently listed all of the reviews I had uncovered (Gottlieb
1995; Holt 1995; Lewin 1995; Masters 1995; Maynard-Smith 1995; Papineau
1995; Ridley 1995; Rorty 1995), along with an anti-Gould sentiment from
John Maynard-Smith's review.  My comments at this point provoked Dennett.
He wrote to me and asked that rather than "badmouthing" his efforts I
should "try to show, in some detailed way, where my [his] analysis is
unfair, mistaken, or even misleading."

        This note to Darwin-List is an explicit attempt to do what he
requests.  I hope that having flushed him out once, he will embrace the
debate and we will hear more from him.  Any of you who wish to return to
the earlier discussions will find the Darwin-L logs archived at
http://rjohara.uncg.edu/darwin/logs/.

        Dennett's position regarding Gould is curious.  His disdain and
dismissal of Gould is tied not to the work itself (in Dennett's estimation
"a mild corrective to orthodoxy at best" (pg. 263 Dennett 1995)) but to the
control that Gould seems to exert over Dennett's critics.  These foes have
rejected or resisted Dennett's work and rubbed his face in the claim that
'Gould has shown that Darwinism is a crock' and so any appeals to Darwinism
are hopeless.  If Dennett's arguments are not evaluated on their own merits
by his colleagues and he sees Gould as the patron saint of those who would
deny him, then we can understand his desire to bring Gould down.  But I
want to distinguish the belief that Darwinism has been gutted of
explanatory force (what Dennett views as the "Gould-myth") from what Gould
has actually done or attempted.  I will be criticizing Dennett's
misunderstanding of theories he ascribes to Gould and not second guessing
the motives of Dennett's critics.  This may already put us at
cross-purposes.

        I find it odd to be an apologist for Gould, he can certainly fend
for himself.  I will not try to simulate him for the Darwin-L.  My lack of
appreciation for baseball (sorry, I am a basketball fan) rules me right out
of contention as Gould's understudy.  I will try to comment as we go along
when I differ with positions Gould has articulated.

        If I have a position on the topic of the current state of
evolutionary theory, it is that evolutionary biology is many leveled,
complicated, and is carried on an ever shifting and expanding empirical
base that when not attended to results in caricature.  We can see one
example of this caricature in Dennett's book.

____

        I will begin by looking at some terminology that Dennett introduces
early in the book, then move through the various arguments that Dennett
touches on in the Gould chapter, and finish by speculating on who the
audience for this book is and what may motivate Dennett's position.

        Dennett makes a distinction between skyhooks and cranes.  Just so
that you don't forget; skyhooks = miracles = bad and cranes = Darwinism =
good.  This analogy is supposed to help us make some of the distinctions
that were traditionally captured in the struggle about teleology and to
reemphasize that evolution must constantly work with what it currently has;
cranes can be used to build bigger cranes but you can't hope for ropes to
hang from the sky.  Though Dennett is quite proud of the crane analogy it
has the unfortunate feature of inviting lay readers to imagine a crane
driver.  We should be cautious about a metaphor that invites such goal
directedness.  It is ironic that someone who claims to have no allegiance
to externalist teleology should deploy metaphors of skyhooks and cranes
(What are they building?  Who is driving?).  I am certain that Dennett
would reject this reading of his image, but I want to offer my reservations
about the metaphor.

        Dennett sees evolution as a process of exploring "design space" an
abstract (possibly platonic) multidimensional space that has designs in it.
I will prefer 'morphospace' leaving designs and all of the functionalism
that they imply as hypotheses that should be deployed critically (this is,
after all, the point of the Spandrels paper (Gould and Lewontin 1979), see
below).  You can imagine an individual organism moving on a trajectory
through morphospace during development.  A population is a cloud in
morphospace, when we add development the cloud gets bigger.  Design space
sounds so end-directed and final.  Concentrating on a design space takes
for granted part of what selectionist theories are meant to explain.  If
everything selected is "designed" and selection is then used to explain
design we have the kind of trivial conclusion that we depend on
philosophers to save us from.  A change to 'morphospace' takes some of the
shine off the skyhook/crane analogy but redirects us to a more important
question; what variation is there for selection to act on.

        Universal selectionist are not usually making claims about the
distribution of variation.  But their (appropriate) emphasis on precisely
that variation that is available to selection in a local population (a
charitable reading of the admonition - "no skyhooks") can give the
impression that they imagine some kind of normally distributed variance
over all morphological variables.  The traditional picture of bell curves
with selection acting to shift the population mean reinforces this notion.
But as is generally acknowledged the neighborhood in morphospace that is
actually explored by a given population is due to a complicated mix of
mutations, translocations, inversions and other genetic events that have
anything but uniform effects on morphology as they affect different
regulatory and structural genes (a dichotomy that sounds more absolute than
it is (compare Nijhout 1990)).  These, in turn, participate in
developmental systems that facilitate and resist changes in morphospace and
are have norms of reaction that can result in very different morphologies
in different environmental contexts (another dichotomy,
environmental/physiological, that implies a divide that isn't easy to
sustain on close examination (this is a large literature, but see Gray
1992)).  Given this, what is the variance for each trait?  This is a major
project in quantitative genetics (a good introductory discussion is Murphy
1979), and no amount of armchair biology will stand in for it.

        The design-space that Dennett asks us to imagine arises from
hypotheses that are made about structures (and behaviors - much of the
preceding paragraph can be applied to an abstract behavioral space).  The
core problem of something like a design space is that the appeal of a
'space' metaphor comes from the sense that there is a meaningful way to
unpack the intuition of distance.  A space has some kind of metric that
lets me say A is closer to B than it is to C.  If we don't really know what
designs are close to others or if we are continuously surprised by how
accessible one design is to another then our space will have an unusable
metric and we will prefer to make an exhaustive list (1).

        Dennett's self claimed contribution to evolutionary theory is that
natural selection is an algorithm.  I have sympathies with the attempt to
view biological processes computationally.  But he manages to dilute the
term so much that in his own estimation, "... are there any limits at all
on what may be considered an algorithmic process?  I guess the answer is
No; if you wanted to, you could treat any process at the abstract level as
an algorithmic process" (pg. 59 Dennett 1995).  So he gets marks for
honesty.  At the same time, he misses a crucial part of thinking about
algorithms; the importance of "data structures" - what is the universe over
which an algorithm works.  What bridge principles allow me to add 1 apple
to 1 apple and get 2 apples while adding 1 sand pile to 1 sand pile can
result in 1 sand pile?  Dennett wants this algorithmic conception to lend
an aura of guaranteed results to selectionism.  Not so fast.  There do
exist algorithms that have provably guaranteed results; some examples can
be found in any introductory text (Cormen, Leiserson et al. 1990).  It
isn't clear what is guaranteed by a selectionist algorithm (2) if we don't
include a lot of information about what kind of variance is possible and
what the basis of selection is.

        As artificial life models become more elaborate it may be that we
will get a sense of both what is guaranteed and over what kinds of data
types selectionist algorithms illustrate those guarantees (Fontana, Wagner
et al. 1994).  There has a been rush to embrace computer models as an
alternate laboratory for evolutionary questions (an interesting laboratory
is described in Ray 1994).  It is important not to assume that we have
reached this goal, as the journey has just begun.  Dennett has an
opportunity to discuss these issues at length after he introduces Conway's
"Life" game and though he acknowledges the skyhook nature of the rules that
govern this game, I really hoped for a more intense light to be shown on
the question of what the patterns perceived by Dennett as he watches the
rules being iterated mean.  He talks about 'gliders' being annihilated by
'eaters' - but what do we learn about the kind of referent Dennett believes
a model should have from this willingness to trade in very abstract
entities.  What should alife models be modeling?  (There is a wonderful
discussion to be had on this topic.)  How do you measure success (3)?

        Understanding what kind of variation is possible and at what level
selection occurs over those variations are what has driven the conversation
about evolutionary biology at least since Darwin.  In his narrative,
Dennett gets the story of evolutionary biology all wrong.  He places his
emphasis on a divide between evil skyhook believers and righteous crane
trusters.  This kind of divide was current in the 1860's (my historian
friends tell me that it was overblown even then.  Did Darwin really, single
handedly refute the Genesis creationists?) not in the 1960's or 1990's (4).
The discussion in evolutionary biology is actually (to use Dennett-speak)
how are the "cranes" made (in detail!) and what is the accessible
neighborhood from a particular point in morphospace.  In these debates
Gould and others have weighed in.

        I entered Dennett's book via the chapter on Gould.  I was trying to
understand Dennett's manic attack (Dennett 1993) on Gould's review of
Cronin's book in the NYR (Gould 1992; Gould 1993).  I had been told by a
member of Darwin-L that I could find Dennett's thoughts on Gould in his new
book (Dennett 1995).  While I did find some thoughts I was more confused
than when I started.  This chapter is full of what seems to me to be at
best uncharitable and at worst willful misreadings of Gould's writings.  He
paints Gould as some kind of anti-Darwinian throughout (compare Gould
1977).  I can't imagine Gould agreeing to this characterization.

        Gould gets kudos for his 20+ year education of the American public
and his anti-creationist stance.  Ah, but his prolific educating is but a
way to fulfill his various agendas.  One of these is Gould's resistance to
ultra-Darwinism which Dennett synonymizes with "his" no-skyhooks Darwinism.
We find that Gould goes from one revolution to the next "crying wolf"
(defying the moral of Aesop's fable).  This all amounts to the idea that
Gould rejects "the very idea that evolution is, in the end an algorithmic
process."  Given Dennett's attenuated all-inclusive sense of algorithm,
what does this mean?

        "The 'no skyhooks-allowed' Darwinism I have presented is, by
Gould's lights, hyperDarwinism, an extremist view that needs overthrowing"
(pg. 264 Dennett 1995). This sentence implies that Gould's description is
pro-skyhooks, that hyper-Darwinism is identical with Dennett's previous
presentation of neo-Darwinism, and that Gould buys this arrangement of the
furniture.  I don't think that Gould would agree with or most fair readers
would find in Gould a sky-hooks-allowed or -encouraged philosophy.  Are we
really to believe that neo-Darwinism is so free of empirical content that a
priori no-skyhooks selectionism is all there is to it?  Is Gould really
tilting at a careful no just-so stories, contingency aware, adaptation for
only some things Darwinism?  I doubt it.  He makes his targets clear.
Dennett may think that he has been unfairly placed into the bullseye but if
in fact he isn't a Panglossian then why is he so nervous?

        "After I began to notice that many of the most important
contributions to evolutionary theory have been made by thinkers who were
fundamentally ill-at-ease with Darwin's great insight, I could begin to
take seriously the hypothesis that Gould himself is one of these." (pg. 267
Dennett 1995)  If Dennett means that Gould is one of the important
contributors to evolutionary theory who is interested in more than a priori
selectionism then I suspect that even Gould would thank him for the
compliment.  But it isn't meant that way - and probably won't be taken as a
praise.  What is it that Dennett thinks all of those important contributors
are doing with their time?  We have to (at least formally) allow that maybe
their discomfort is with the kind of universalized Darwinism that Dennett
wants to synonymize with what is presented in Darwin's work as seen through
the eyes of Dawkins.

        Dennett challenges the spandrels of San Marco paper (Gould and
Lewontin 1979).  This is Gould and Lewontin's  forceful statement against
explaining every feature as an adaptation.  Dennett insists that none of
the befuddled biologists who use this paper as a corrective for their
students know what they are talking about (pg. 267-282 Dennett 1995).  Poor
Dennett, even his ally Maynard-Smith allows that "By and large, I think
their paper had a healthy effect.  There are plenty of bad adaptive
stories... Their critique forced us to clean up our act and to provide
evidence for our stories." (Maynard-Smith 1995)  So contra Maynard-Smith
Dennett claims that Gould was preaching to the converted and no "good"
evolutionists ever went to the excesses that the Panglossian adjective
implied.

        How could Dennett get it so wrong?  Maybe the path of the argument
will help.  We are treated to a long explanation of how domes can be placed
on walls without forming spandrels (which it turns out aren't even really
called 'spandrels').  And it goes on and on - only to end by claiming that
in fact not all features are adaptations; "Natural selection could still be
the 'exclusive agent' of evolutionary change even though many features of
organisms were not adaptations."  This simply moves the goal post.  If we
synonymize 'evolutionary change' with 'natural selection' then sentences
like the above are not very interesting.  Dennett's discussion of the
Spandrels paper shows a pattern of an obsessive attention to the wrong
details.  The spandrels paper is used and taught often because people do
make the "adaptations everywhere" mistake.

        Dennett's treatment of Gould and Vrba is curious, because he seems
to buy (completely) the notion of appropriation of features that weren't
designed for their current use.  In fact, his no skyhooks rule requires
this of him.  He seems to be saying that since you can go back to a time
when "you will find that every adaptation has developed out of predecessor
structures each of which had some other use or no use at all" (pg. 281
Dennett 1995) that there is no useful category for features not evolved
under natural selection for their current use.  Does allowing this formal
notion (everything is an exaptation) gut the word of any utility?  Most of
the molecular evolutionist I know don't seem to think they need this word.
But they certainly have the situation arise.

        Let me illustrate with an example from protein evolution (others
have had plenty to say about organ-level exaptations (Gould and Vrba
1982)).  A protein involved in (5) transporting soluble antibodies from
mother's milk across the lumen of the gut (FcRn) is a heterodimer.  The
heavy chain of FcRn is related to the MHC class I proteins (paralogously)
(6).  There is some circumstantial evidence that these proteins diverged
around the time of the ancestor to lizards and mammals(Ahouse, Hagerman et
al. 1993).  One of the domains of Ameiva lizard MHC class I is slightly
more similar to part of the mouse FcRn heavy chain than the same domain
from the MHC of other mammals.  This conclusion has recently received
support from a group who has examined the genomic structure of the mouse
gene (Kandil, Noguchi et al. 1995).  It turns out that FcRn uses a very
different part of the molecule to bind its ligand (the antibody) that the
MHC molecule does to bind its ligand (a peptide) (Burmeister, Huber et al.
1994).  Importantly the binding is not near the MHC peptide binding groove.
Is this an example of what Gould and Vrba call 'exaptation'; "=8Afeatures of
organisms are non-adapted, but available for useful cooptation in
descendants" (Gould and Vrba 1982)?  The domain that is coopted for the
function of binding in FcRn may be critical for the function of MHC - just
not used for binding and subsequently appropriated.  In this context it
could have a coherent use, since we aren't really ready to move back to the
ancestor of all MHC extracellular domains.

        Dennett tells us that Gould has complained that the target of his
criticism is moving (pg. 281 Dennett 1995).  Gould's frustration that the
neoDarwinian synthesis doesn't sit still, adsorbing and embracing new ideas
as they make themselves known shouldn't get too much sympathy.  At the same
time, being able to rapidly cleave to new ideas is not the same as always
having stood for them yourself.  Dennett repeatedly belittles Gould's
contributions by claiming that they were always there.  Priority is
important and no one likes to be grabbed by the collar and told
passionately how important it is to believe what one already believes.  So
Dennett will need to argue more convincingly that all of Gould's mild
correctives were an extant and vivid part of the synthesis to bring me on
board.

        Dennett then moves to a discussion of punctuated equilibrium (7).
He does what he can to confuse a straightforward central claim;
morphological stasis is found throughout the fossil record.  Adaptive
gradualism does not lead us to expect this.  That's the main point.
Dennett confuses the issue (as others have) by focusing on the punctuations
not the equilibrium.  It is stasis that is surprising in a gradualist all
features varying world.  How would you explain stasis if you don't let
yourself appeal to constraints in variation?  You would depend on
stabilizing selection - as people have.  But claiming that all stasis is
due to stabilizing selection is a controversial move.  Is it discussed as
such by Dennett?  Nope.  He offers us the idea that species are
intrinsically conservative, that species are tracking stable environments,
and that it is due to a purely theoretical explanation (that we aren't told
about) and from this we are to conclude that, "It is quite clear, then,
that equilibrium is no more a problem for the neo-Darwinian than
punctuation" (pg. 294 Dennett 1995).

        Gould and others have taken the observation about stasis to make
plausible species sorting as an explanation in macroevolutionary dynamics
(Gould and Eldredge 1993; Gould 1994).  The discussion regarding species
selection is ongoing and enthusiasm for or against it seems to have
everything to do with what scale you are examining.  In explaining the
diversity and abundance of various forms at a particular time and place we
press a number of explanatory machines into service.  Dennett, it seems,
would insist that every (evolutionary?) feature of distribution and
abundance is best explained by local adaptation.  Is this true?  Certainly
not.  We are then left with the issue of deciding what features to
foreground as we tell the story of life.  Parts of that story invite
highlighting adaptationism (the changes in primate limb structure (Fleagle
1988)) others macroevolutionary dynamics (extinctions in the marine fossil
record (Raup and Sepkoski 1982)).

        What do we know about variation and the accessible morphological
neighborhood?  The last few years have yielded a bounty of information.
Much of this work has come as thanks to years of Drosophila genetics (let
us bow our heads in thanks to all those technicians and post-docs who
maintained inbred lines for all those years!).

        One of the important parts of the adaptationist tale has been the
idea that similar environments can generate similar solutions (convergence
or parallelism).  Examples that are often marched out involve the similar
forms of marsupial and placental mammals (the marsupial cat and dog and the
placental rabbit that moves just like a kangaroo) or the streamlining that
is shared by dolphins and tuna.  Not bad examples.  The other side offers
long lists of organisms that don't have convergent partners, my favorite is
the woodpecker.  So what happens when one of the favorite examples from one
column is yanked into the other...

        The evolution of the eye stood for years as an example of
independent evolution fulfilling the same need.  Vertebrates and mollusks
have single lens eyes (though the photoreceptive cells under the lens have
opposite orientation) while insects have compound eyes.  These differences
had been taken to imply that the eye evolved (independently) numerous times
(Salvini-Plawen and Mayr 1977).  Now it looks (pun!) as if the large
morphological differences share a common developmental pathway for eye
morphogenesis.  The evidence for homology in the developmental pathways
comes from looking at the orthologous protein in mammals and flies.  The
original paper claiming homology between mouse (Pax-6) and fly (eyeless)
was in 1994 (Quiring, Walldorf et al. 1994).  Subsequent work in the same
lab showed that misexpression of the eyeless protein could give rise to
eyes on wings and legs.  This story was reviewed in Natural history in
December of that year (Gould 1994) and a nice review recently came out in
Current Opinion in Genetics & Development this year (Halder, Callaerts et
al. 1995).  What do we take from this deep homology?  Does this mean that
there is no selection - of course not!  But it does sensitize us to the
importance of the lineage and suggests that at a minimum if there is even
the slightest backdrop that can be used in a new context this developmental
path has been followed and more challengingly maybe selection doesn't have
the latitude that we might want to give it.  If the Pax-6 cascade hadn't
been extant in the lineage that led to insects, chordates and mollusks
would there have been eyes in these lineages?

        Can the variation that selection operates on include a visit to the
past?  Anyone interested in animal development these days will find
themselves learning about a group of genes called the Hox genes.  These
genes originally identified because their mutant forms resulted in
transformations of body segments are fascinating.  These mutants underline
the ability of small genetic changes to have profound morphological
consequences (not news - but underlined nonetheless).  Even more
fascinating is recent work showing that changes in some Hox genes can
result in ancestral morphologies reemerging.  The ancestral condition for
the mammalian ear ossicles is a single bone homologous to the stapes
(stirrup).  The familiar malleus (hammer) and incus (anvil) are derived
from the articular (lower jaw) and quadrate (upper jaw).  Scrambling the
Hoxa-2 gene in mice changes the pharyngeal arches during development
resulting in the ancestral condition (Lufkin, Mark et al. 1992).  A similar
thing is seen in Hoxb-8 and Hoxc-8 manipulations where rib and vertebral
atavisms are seen (Pollock, Tadru et al. 1995).  The ancestral one wing per
segment can be seen in manipulations of insect Hox genes (Carroll,
Weatherbee et al. 1995).  The hypothesis that flowers derived from leaf
tissue is lent support by plant mutants that show whole flower structures
where anthers, stamens, petals and sepals can be replaced by leaf tissue
(Weigel and Meyerowitz 1994).  This should not be taken to imply that the
intricate derived states (getting the four whorls of flower tissue from
leaf tissue) are only a couple of mutations away from the ancestral
condition, rather these mutations emphasize that certain (surprising?)
forms are close to extant forms and evolutionary dynamics may be dependent
on the possibilities that are "stored" in these developmental pathways.
(see also Day 1995)

        I raise the examples of deep homology and atavism to remind you
where one of the foci of current discussion in evolutionary biology rests.
The argument is not in some kind of tension between mystics and realists.
To read Dennett you wouldn't get the sense that any of this was happening.
How misleading is it to write a book that avoids the current intellectual
activity in the discipline?

        Dennett ends his chapter on Gould with a discussion of Gould's
Burgess Shale book (Gould 1989).  Dennett writes, "Gould speaks here not
just of unpredictability but of the power of contemporary events and
personalities to "shape and direct the actual path" of evolution.  This
echoes exactly the hope that drove James Mark Baldwin to discover the
effect now named for him: somehow we have to get personalities -
consciousness, intelligence, agency - back in the driver's seat.  If we can
just have contingency - this will give the mind some elbow room so it can
act, and be responsible for its own destiny, instead of being the mere
effect of a mindless cascade of mechanical processes!  This conclusion, I
suggest, is Gould's ultimate destination, revealed in the paths he has most
recently explored." - (pg. 300 Dennett 1995)  This doesn't resonate with my
take on Gould's project.  I leave it to you to put this analysis somewhere
on the spectrum from on-target to uncharitable to misleading.

        Jeremy C. Ahouse
        Biology Department
        Brandeis University
        Waltham, MA 02254-9110
ph:     (617) 736-4954
fax:    (617) 736-2405
email:  ahouse@hydra.rose.brandeis.edu
            _        _
           /\\     ,'/|         "Truly speaking,
         _|  |\-'-'_/_/         it is not instruction,
    __--'/`           \         but provocation,
        /              \        that I can receive
       /        "o.  |o"|       from another soul."
       |              \/                - R.W. Emerson
        \_          ___\
          `--._`.   \;//
               ;-.___,'
              /
            ,'
         _-'

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Darwin-L Message Log 28: 1-17 -- December 1995                              End

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