Reflectorites
On Thu, 27 Apr 2000 14:13:48 -0500, Susan Brassfield wrote:
[...]
>SJ>As I said, Susan didn't even quote the entire *quote*! The fact is that
>>Susan omitted words from the same quote which were irrelevant to the
>>point *she* was making as I did.
SB>I still don't understand the relivance of this however, for the record,
>here is a part of my original post:
>------
>Stephen [speaking to Chris]:
>SJ>This is too vague. Complexity could apply only to oscillating variations of
>>the beaks of finches on the Galapagos Islands. Is Chris claiming that *all*
>>the complexity of life, over the last 3.8 billion years, came *only* by
>>"variations, some of which themselves produce even more complex
>>variations"? That's OK, but he should then acknowledge that it is
>>controversial even among evolutionists:
>
>Me:
>what Chris talks about above has been observed to occur and isn't
>controversial. However, this quote below brings me to the topic of the post.
>
>>"Orthodox neo-Darwinians extrapolate these even and continuous changes
>>to the most profound structural transitions in the history of life: by a long
>>series of insensibly graded intermediate steps, birds are linked to reptiles,
>>fish with jaws to their jawless ancestors. Macroevolution (major structural
>>transition) is nothing more than microevolution (flies in bottles) extended.
>>If black moths can displace white moths in a century, then reptiles can
>>become birds in a few million years by the smooth and sequential
>>summation of countless changes. The shift of gene frequencies in local
>>populations is an adequate model for all evolutionary processes - or so the
>>current orthodoxy states....The fossil record with its abrupt transitions
>>offers no support for gradual change...Yet the unnecessary link that Darwin
>>forged became a central tenet of the synthetic theory." (Gould S.J., "The
>>Return of the Hopeful Monster", in "The Panda's Thumb", 1990, p156)
[...]
Here is the whole *page* (and a bit of the preceding page) for the
context:
==========================================================
155
{Orthodox neo-Darwinians extrapolate these even and continuous changes
to the most profound structural transitions in the history
156 THE PANDA'S THUMB
of life: by a long series of insensibly graded intermediate steps, birds are
linked to reptiles, fish with jaws to their jawless ancestors. Macroevolution
(major structural transition) is nothing more than microevolution (flies in
bottles) extended. If black moths can displace white moths in a century,
then reptiles can become birds in a few million years by the smooth and
sequential summation of countless changes. The shift of gene frequencies in
local populations is an adequate model for all evolutionary processes - or
so the current orthodoxy states.
[The most sophisticated of modern
American textbooks for introductory biology expresses its allegiance to the
conventional view in this way:
`[Can] more extensive evolutionary change, macroevolution, be explained
as an outcome of these microevolutionary shifts? Did birds really arise from
reptiles by an accumulation of gene substitutions of the kind illustrated by
the raspberry eye-color gene?
The answer is that it is entirely plausible, and no one has come up with a
better explanation...The fossil record suggests that macroevolution is
indeed gradual, paced at a rate that leads to the conclusion that it is based
upon hundreds or thousands of gene substitutions no different in kind from
the ones examined in our case histories.'
Many evolutionists view strict continuity between micro- and
macroevolution as an essential ingredient of Darwinism and a necessary
corollary of natural selection. Yet, as I argue in essay 17, Thomas Henry
Huxley divided the two issues of natural selection and gradualism and
warned Darwin that his strict and unwarranted adherence to gradualism
might undermine his entire system.]
The fossil record with its abrupt
transitions offers no support for gradual change,
[and the principle of
natural selection does not require it - selection can operate rapidly.]
Yet the
unnecessary link that Darwin forged became a central tenet of the synthetic
theory.}
Goldschmidt raised no objection to the standard accounts of
microevolution; he devoted the first half of his major work, The Material
Basis of Evolution (Yale University Press, 1940), to gradual and
continuous change within species. He broke sharply with the synthetic
theory, however, in arguing that new species arise abruptly by
discontinuous variation, or macromutation. He admitted that the vast
majority of macromutations could only be viewed as disastrous-these he
called "monsters." But, Goldschmidt continued, every once in a while a
macromutation might, by sheer good fortune, adapt an organism to a new
mode of life, a "hopeful monster" in his terminology. Macroevolution
proceeds by the rare success of these hopeful monsters, not by an
accumulation of small changes within populations.
(Gould S.J., "The Return of the Hopeful Monster," in "The Panda's
Thumb: More Reflections in Natural History," [1980], Penguin: London,
1990, reprint, pp.155-156. Ellipses in original.)
==========================================================
I have enclosed my original quote in {} and the words I omitted in [], and
moved them to the next line.
The second block of words that I left out that "selection can operate rapidly" I
considered to be irrelevant to my question to Chris about "variation".
The first block I omitted was where Gould is contrasting the claim in one
of the "modern American textbooks for introductory biology" (by E.O.
Wilson) that "macroevolution is indeed gradual...based upon hundreds or
thousands of gene substitutions" with T.H. Huxley's warning to Darwin
that such "strict and unwarranted adherence to gradualism might
undermine his entire system".
In fact including both blocks would actually have strengthened my claim
that this was "controversial even among evolutionists"!
I am therefore more than happy to put *both* blocks back in and debate
the full quote (or the whole page, or the whole chapter)!
Now does Susan or Chris want to re-start the debate about: 1) whether
"Chris" is "claiming that *all* the complexity of life, over the last 3.8 billion
years, came *only* by "variations, some of which themselves produce even
more complex variations"?" and if so; 2) whether that is "controversial
even among evolutionists"?
If so I would be happy to oblige either or both of them.
In anticipation that they might want to re-start the debate, and to save
time, I would point out : 1) the title of Gould's chapter "The Return of
the Hopeful Monster"; and 2) Gould's last point on the above page
that:
"Goldschmidt ... broke sharply with the synthetic theory, however, in
arguing that new species arise abruptly by discontinuous variation, or
macromutation."
Now if Chris wants to argue that even "discontinuous variation, or
macromutation" is still "variation" then I would have no argument with
him. Of *course* it is, in the sense that a modification of an existing
organism is technically a "variation". But even God creating a new
design by supernaturally modifying an existing design would be a
"variation" in that sense.
But that is not the *Neo-Darwinist* "synthetic theory" definition of
*continuous* "variation", which is that: "macroevolution is indeed
gradual...based upon hundreds or thousands of gene substitutions".
That was all that my point was, that this was "OK" but that Chris "should
then acknowledge that it is controversial even among evolutionists".
Susan's interjection of a "Why lie?" ad hominem and an `out-of-context'
quote allegation just muddied the water and prevented a rational debate
between Chris and I on this issue.
Steve
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"The ability of species to adapt by changing one base pair at a time on any
gene, and to do so with comparative rapidity if selective advantages are
reasonably large, explains the fine details of the matching of many species
to their environment. It was from the careful observation of such matchings
by naturalists in the mid-nineteenth century that the Darwinian theory
arose. Because the observations were made with extreme care, it was
highly probable that immediate inferences drawn from them would prove to
be correct, as the work of Chapters 3 to 6 shows to be the case. What was
in no way guaranteed by the evidence, however, was that evolutionary
inferences correctly made in the small for species and their varieties could
be extrapolated to broader taxonomic categories, to kingdoms, divisions,
classes, and orders. Yet this is what the Darwinian theory did, and it was
by going far outside its guaranteed range of validity that the theory ran into
controversies and difficulties which have never been cleared up over more
than a century." (Hoyle F., "Mathematics of Evolution," [1987], Acorn
Enterprises: Memphis TN, 1999, p.137).
Stephen E. Jones | sejones@iinet.net.au | http://www.iinet.net.au/~sejones
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