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Occam's bulldozer & natural selection & ceratopsians



    By stating "natural selection" does not exist, I
am saying that it is, basically, an adjective. By
itself, "natural selection" (prior to the work of Hugo
de Vries and August Weismann) has been a "buzzword":
when knowledge failed, the post-1859 (bio)ontologists
would just say, "oh, the explanation is in natural
selection". 
    Stu Kauffman, et al., have for years grappled with
the processes of evolution, adaptive landscapes,
plastid and nuclear DNA sequences, "hopeful monsters",
etc. Inherited character traits are undeniable, but
the "how" they are transferred/inherited is a complex
array of biochemicality not served by just stating
"natural selection". What we are dealing with (and I
apologize for the simplistic parameters of this note)
is: 1)a common ancestor producing an abundance of
offspring; 2) variation in these offspring; 3) and the
heritability of the mixture of variabilities to future
offspring. One of the major components is, of course,
disease resistance.
     In his last book, Stephen Gould called the three
components agency, efficacy, and scope. The major
"engine" of evolutionary adaptationism (the "natural
selection" of the 1850s) is, of course, changes in the
genomes of populations over time. George Gaylor
Simpson, in a collaborative 1957 textbook, stated:
"The evolutionary changes that result from nonrandom
reproduction are clearly adaptive: the changes are
always, necessarily, of such a kind as to improve the
average ability of the population to survive and
reproduce in the environments that they inhabit". As
Stu Kauffman titles his important book, it is the
ORIGINS of order. Order, natural selection, and other
formulations are, thus, to be rooted in the engines of
the genome on the edge of chaos.
   Stu Kauffman writes:
Highly constrained, poised cell types and ordered
patterns of gene activity, each able to change to only
a few others, are gratuitously present in a vast class
of genomic regulatory systems [NOTE: if one is to use
"natural selection", then this phrase by Stu Kauffman
is pivotal, "genomic regulatory systems"]...The phase
transition from one regine to another is governed by
simple parameters of the system, such as richness of
coupling among the variables. The order seen in
ontogeny, I shall suggest, is just that which arises
spontaneously in the powerfully ordered regime found
in parallel-processing networks. Selection, I shall
further suggest, by achieving genomic systems in the
ordered regime near the boundary of chaos, is likely
to have optimized the capacity of such systems to
perform complex gene-coordination tasks and evolve
effectively.
    Let me use an example. Stu Kauffman speaks of
evolution being "primarily an emergence of states
generic to the dynamics of living systems". If, say,
we have a population of strikingly varied centrosaurs
(the female "styracosaurs" in matrilineal herds, these
information centres for raising young and dominating
"centrosaur" males). To survive
generation-to-generation, these animals had to have
sustained evolvability in their genomic systems,
evolvability being the mechanism, as it were, for
morphology of the animals. These are "selection"
components for the dinosaurs (then and now, by the
way). To paraphrase Stu Kauffman, generations of
ceratopsians would be the expected collective property
of complex systems of catalytic polymers and the
molecules on which they act. All dinosaurs, then and
now, represent what Stu Kauffman terms "a collective
self-reproducting metabolism in a space of possible
organic reactions".
   For me, e.g., there are two important aspects of
dinosaur evolution: their interactions on rugged
fitness landscapes (predator-prey dynamics,
brooding/hunting/foraging/predator-prey avoidance
strategies); the capitulation of ontogeny. With each
generation of a dinosaur population surviving (our
matrilineal herd), the parameters of adaptive peaks
(how "high" these peaks are) double after each
generation. The contingency of dinosaur populations,
thus, were historical (time-based). Can one infer
statistical paradigms from dinosaur populations? Let
me propose a dreamscape, so to speak. Imagine we are
in a helicopter high above a ceratopsian herd on a
hillside, and it begins to rain. Each member of the
herd is dripping with water, the rivulets on the
ground branching and eventually converging to form a
small stream draining down the hill. The branching
patterns of water will be unique to each animal, how
each animal is positioned on the hill side relative to
herd mates, direction of breezes, etc. Seen from
above, however, we see not individual ceratopsians,
but a herd, what Stu Kauffman and others call
"adaptation to the edge of chaos".
   I would also add that, often, too much emphasis is
placed in dinosaur phylogenies on history of certain
lineages rather than trying to link these to "higher
level systematics", e.g., and I share with Kauffman a
discomfort with "branching" preoccupations. I do not
believe a breeding population of dinosaurs (say, a
colony of penguins)are accidents and historically
contingent. Microevolutionary mechanisms, perhaps, may
not have all of the answers. The spatiotemporally
invariant laws of nature (as S.J. Gould elegant puts
it), as applied to dinosaurs, demonstrate that
punctuated equilibrium forms a speciational data
matrix of trends within clades, enabling one (if
enough specimens are known) to infer macroevolution of
dinosaur lineages, the "hows" and "whys" certain
characters enabled some clades to persist through
time. (Theropoda survived them all, so that, 65
million years later, only theropods live.) And  the
reality of catastrophic mass extinctions suggests
that, among survivors, coordinated and persistent
survival is more important than some realize. David
Raup has said "that pulses of extinctions of genera
must be connected in some way...because of common
factors, such as ecological interdependence or shared
physical stress. We thus see a picture of episodic
extinction wherein the more intense an extinction
episode, the rarer it is. To describe extinction only
as background or mass extinction, as is commonly done,
is to hide much of the structure of the extinction
phenomenon". 
    Per Bak's "sandpile" paradigm of self-organized
criticality, among other avenues of thought, are tools
to sort through the mechanisms of adaptationism.
Another method (setting aside the fascinating CGI of
Kent Stevens, Phil Tippett, et al. to study
biomechanics of locomotion, and the works of Colin
Pennycuick to see CGI flocking behaviour) to study
dinoaurs, then, is the creation in computers of
virtual dinosaur realities. Thomas Ray, in a 1991
symposium and major 1992 paper, points the way (some
have called it "Artificial Life"). One could (and why
this has not been done with dinosaurs is a puzzle to
me), using the computer programmes of Tom Ray et al., 
create a dinosaur herd/flock's self-replicating
algorithms.
   One would go from simple models of coevolution of a
dinosaur population to punctuational changes in
lineages. Stu Kauffman points to three components of
what we are alluding to (taken together, I suppose,
these could be "natural selection"): 1) "the tendency
of complex dynamical systems to fall into an ordered
state without any selection pressure whatsoever"; 2)
the life of these dinosaurs being "self-regulation of
the genome to produce well defined cell types"; 3)"the
postulated sudden waves of evolutionary change known
as 'punctuated equilibrium'".
   In a network of predator-prey dynamics, let us say,
a predator may, in effect, cease to evolve, and the
prey compelled to transform its lineage into a new
taxon, stasis > periods of punctuated equilibrium, new
homologies and analogies.
    Occam's bulldozer needs fuel now and then.



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