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Darwin-L Message Log 1:217 (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.


<1:217>From TREMONT%UCSFVM.BITNET@KUHUB.CC.UKANS.EDU  Mon Sep 27 08:15:23 1993

Date: Mon, 27 Sep 1993 05:27:46 -0700 (PDT)
From: "Elihu M. Gerson" <TREMONT%UCSFVM.BITNET@KUHUB.CC.UKANS.EDU>
Subject: Re: Heritability and cultural evolution
To: darwin-l@ukanaix.cc.ukans.edu

I think the discussion between Holsinger and myself is wandering far
from the point. My original point was that parallels between biological
evolution and cultural evolution are very difficult to draw, because
the material and efficient causes of each are very different and not
comparable, no matter how similar the mathematical models describing
them become. By which I meant, for example, that changes in technology
are not sexually transmitted.

So yes, one can have a perfectly good FORMAL theory of biological evolution,
but that theory is of no value to understanding cultural change
precisely because it suggests nothing about how the change takes place.
One need only look at attempts to draw cultural analogies with the parts of the
biological evolution process to see how fruitless this can become--
endless  attempts to decide what is the "gene" and so on, when the
analogies are simply untenable.

What we need are viable theories of cultural and institutional change. Then,
if it turns out that there are neat analogies between those theories and
biological theories, that will be very interesting. But it serves no good
purpose to assume such analogies exist a priori, and then try to force
an interpretation of the institutional arrangements we see.

As to the history of evolutionary theory-- that's really another whole
discussion. I wasn't talking about the "rediscovery of Mendel". Mendel's
theory is a formal abstract theory of "factors" with no material
content. So is Fisher's, and so is Wright's. The pertinent discoveries
which put material content into those theories came from cytology. That
body of knowledge developed very rapidly after 1910, although
it got a big boost in 1902 - 1904, with the hypothesis
that the hereditary "factors" were located on the chromosomes.

The opposition of de Vriesian "mutationists" and "Mendelians" to
natural selection was based on their perception that hereditary changes
had to be large in effect. This point of view died out very rapidly
after 1910 (more rapidly in the US than in England) for many reasons.
Work in both cytology and population genetics gave results inconsistent
with that view, and the competing mendelian-chromosome model was extended
very effectively to explain new phenomena as well.

So we had scientists who accepted natural selection (e.g., D.S. Jordan
and Joseph Grinnell in this country), but who had no idea of what the
material causes of heredity might be. Nor did they care, because they were
concerned with speciation, adaptation, and geographical distribution.
There also were people concerned with the material causes of heredity
and development, who didn't see how natural selection could bring about
what they assumed to be necessary. But they didn't care about speciation
adaptation and distribution. Weismann was a rare exception here.

And finally, there were many scientists in the latter part of the 19th
century, before the "rediscovery of Mendel", who were concerned with
speciation, adaptation, and so on, and who did not accept Darwin's
natural selection model. Most paleontologists for example. Even those
who wanted to accept it (Romanes, for example) were forced to extend
or modify it, because the natural selection model, as formulated by
Darwin, doesn't explain origin of species. In order to make it explain
origin of species, some form of isolation between populations has to
be introduced. Romanes tried to do this with his concept of "physiological
selection", which we would call isolating mechanisms today.

So, to come back to the point finally: if you believe that we only need
to know *that* offspring resemble their parents, and that *how* (not "why")
they do so isn't important, then we had a complete model of evolution in
1904 with the publication of Grinnell's paper on the Chestnut-backed
Chickadee in _The Auk_.  But many biologists, especially those who saw an
ith heredity and development as well as

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