Glenn,
I commend you on your detailed reports of the conference at Baylor. I admire
how well you caught the spirit as well as the substance of many aspects of
the conference.
Since you invited me to comment on your report of my presentation, I'll do
so. You wrote, "While there was much I still disagree with, he seems to be
more evolutionary than he used to be. In fact, Bob was kind enough to credit
me for moving him in that direction."
Comment: At one time I thought that evolution was in opposition to what I
interpreted to be evidence for developmental processes at work in the fossil
record, which I called by various names--phyletic development,
macrodevelopment, or taxonomic development. I have now expanded the concept
of “phyletic development” into “Phyletic Life Span Processes” (PLSP) which
includes, phyletic development, growth, and aging, all of which are parallel
to individual life-span processes.
When the concept of Intelligent Design came into being, I had three processes
to play around with--ID, PLSP, and Darwinian evolutionary mechanisms.
The question arose, how are these three processes related to each other? I
realized that they could not be opposed to each other, since they are all
bona fide processes in nature. It occurred to me that they are related
historically, that they occur in a chronological sequence in the history of
life in the universe. They occurred as overlapping causal domains. The
first and primary causal agent is Intelligent Design, which can be inferred
most clearly in the pre-biotic universe, and also in the origin of life, the
origin of the eukaryotic cell, in the Cambrian explosion, and in the origin
and development of human beings.
Phyletic Life Span Processes came into being next, as the second major causal
process, with the appearance of body plans of multicellular animals
(metazoans) found in the Precambrian. Glenn quoted a passage from Valentine
and Hamilton, that Paul Nelson used, that captures the developmental aspect
of PLSP. "The basic features that underlie the development of body plans are
not simply genomes but are developmental fields, fields of patterning that
are first found in the egg and produce cells whose fates and positions are
progressively specified during morphogenesis so as to produce a given
polarity, region, organ or other structure as development unfolds....Thus, an
ancestor can be viewed, not just as so much genetic information or as a
combination of some particular somatic features, but as including a
developmental process involving them both. Using a developmental ancestor
stresses the fact that, after all, the Metazoa owe their very existence to
their ability to produce differentiated cells that form a level in a somatic
hierarchy." James W. Valentine and H. Hamilton, "Body plans, phyla and
arthropods," in R. A. Fortey and R. H. Thomas, eds., _Arthropod
Relationships_ (London: Chapman & Hall, 1997), pp. 1-9; p. 3.
This is a remarkable quotation. Not a word is said about Darwinian
mechanisms. It is beginning to be recognized that developmental processes
were at work not only in individual organisms, but through them, in phyletic
lineages.
In my paper at Baylor, I presented research that strongly suggests that PLSP
were at work as well in the organization and discontinuities of phyletic
lineages that followed the Cambrian explosion. Phyletic lineages develop
hierarchically, from the very start, as Valentine and Hamilton state, i.e.,
from the topdown. The fossil record is clear on this topdown procession.
These lineages also follow a growth curve that rises from tiny beginnings to
a maximum which then declines and in many cases dies out or becomes extinct.
In the downside of the curve phyletic lineages show all the characteristics
of aging, general decline and disorganization.
Thus, at the time of the Cambrian explosion, PLSP rose to a maximum of
real-time causality, and slowly fade as the lineages gradually actualize
their total potential, following their developmental course through geologic
time.
Glenn may call PLSP "a throwback to some of the earlier paleontology in last
century" if he wishes. But there is substantial empirical evidence to
support the concept of Phyletic Life Span Processes that was not available to
19th century paleontologists. It would be better to deal with the evidence
than to dismiss the idea out of hand as an out-of date idea.
Darwinian Evolutionary mechanisms constitute the third major causal process,
and can also be inferred at about the same time as PLSP came into being.
Their function is to preserve and adapt what Intelligent Design created and
PLSP organized. While PLSP account for the organization and discontinuities
of the biota; Darwinian mechanisms account for its remarkable variety. As
the curve of PLSP processes declines the curve of evolutionary processes
rises. Therefore at the present time Darwinian mechanisms are at the maximum
while ID and PLSP are at a minimum.
I concluded my paper with this:
I have presented evidence for an intervening family of processes called
Phyletic Life-span Processes, which can be inserted and partially fills the
gap between prior Intelligent Design and later Darwinian Evolution. Phyletic
Life span processes share with Intelligent Design its teleological or goal
directed characteristics; which is to insure that major groups of animals
attain their full genetic and morphological potential and are separated from
other groups by following their own unique developmental and growth paths.
Phyletic Life Span processes provide a biological agency by which design is
transmitted, maintained and expanded in the biological world. What
Intelligent Design innovates Phyletic Life Span Processes organize and
complete.
On the other side, Phyletic Life Spans share with Darwinian Evolution the
ongoing shaping and sculpting of animal morphology, a process that is carried
forward even into the present time by Darwinian mechanisms. What Phyletic
Life Span Processes complete Darwinian mechanisms adapt for survival.
Any explanation of the history of life in the universe is incomplete without
reference to at least these three causal agents of change.
If any one would like a copy of my presentation send me your mailing address
and I will sent it to you.
Thanks, Glenn, for your comments on my presentation at the conference. Our
catfish dinner and evening's conversation remains a most pleasant memory.
Bob
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