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WAAS General Assembly
Hyderabad, India October 17-19, 2008
Darwinism: Dead Wrong?
Evolution ≠ Adaptation
Writ Large
Jeffrey H. Schwartz
President, World Academy of Art & Science
Departments of Anthropology
and History and Philosophy of Science
University of Pittsburgh
Gradual accumulation of infinitesimally small changes
favored by natural selection because they are adaptively
advantageous
In other words, Evolution is Adaptation writ large which conflates two entirely different biological
phenomena:
1) the advent of the feature/novelty (taxic diversity),
and
2) the subsequent emergence of individual variation
(i.e. slight degrees of difference in the expression of
a feature or features among individuals of a
species).
Thomas Henry Huxley and an alternative to
gradualism - saltation:
“…it is more than probable that the majority of
varieties have arisen in [a] ‘spontaneous’
manner…[and] once in existence, varieties obey the
fundamental law of reproduction that like tends to
produce like, and their offspring exemplify it by
tending to exhibit the same deviation from the
parental stock as themselves.” (Huxley, 1860, review of Origin)
St. George Mivart, the leading saltationist:
“…it is probable that new species have appeared
from time to time with comparative suddenness, and
that they still continue so to arise if all the conditions
necessary for specific evolution now obtain.” (p. 236)
“…new forms must be produced by changes taking
place in organisms in, after or before their birth,
either in their embryonic, or toward or in their adult,
condition.” (p. 233)
Hugo de Vries
Wm. Bateson
Th. H. Morgan
Evolution and Adaptation must be decoupled!
R. Goldschmidt
O. Schindewolf
“Micro-” versus “Macro-evolution”
Richard
Goldschmidt: The
Material Basis of
Evolution (1940):
Systemic mutations,
‘hopeful monsters’,
cites Schindewolf
(1936) for support
from the fossil record
Repeated parts!!
Schindewolf on Goldschmidt’s Material Basis:
“Th[e] explanatory attempt by Goldschmidt has
aroused much opposition among other
geneticists. Paleontology has no right to
intervene on this dispute. From my personal point of
view, I can add only that Goldschmidt’s inferences
completely meet the challenge that fossil material
appears to me to pose, and that he, a leading
geneticist, has presented a completed
interpretation that does justice to the tangible,
historical phylogenetic data.” (Basic Questions, 1950,
trans. 1993, p. 352; bold added)
Schindewolf’s overview:
“The production of basic structural designs takes
place independent of the environment and of the
mode of life: the neomorphic organs are at first neutral with
regard to their function and appropriateness; at first, their
significance is completely incidental, and they do not attain value and this usually in an environment different from the original one until after they have acquired a certain degree of development and,
with that, the capacity for being useful…the quality and
quantity of neomorphs…are determined exclusively
by the organism itself…you can’t make an elephant
out of a mosquito [in other words, adult forms do not
evolve].” (1950, trans. 1993, p. 372; bold/comment added added)
The “modern synthesis”: constraining biology to a
melding of Darwinism & Population Genetics
E. Mayr (1942)
Systematics & the
Origin of Species
T. Dobzhansky (1941)
Genetics & the Origin
of Species (2nd ed)
G. G. Simpson (1944)
Tempo & Mode in
Evolution
T. Dobzhansky re-writes Genetics and the Origin of
Species (1st ed, 1937) basically to attack Goldschmidt:
“It is possible to imagine a mutation so drastic that its product
becomes a monster hurling itself beyond the confines of species,
genus, family, or class. But in what Goldschmidt has
called the ‘hopeful monster’ the harmonious
system, which any organism must necessarily
possess, must be transformed at once into a
radically different, but still sufficiently coherent,
system to enable the monster to survive. The
assumption that such a prodigy may, however rarely,
walk the earth overtaxes one’s credulity, even though
it may be right that the existence of life in the cosmos is in itself an
extremely improbable event.” (Genetics and the Origin of Species, 2nd
ed, 1941: 52-53; bold added)
Mayr enters the fray - on speciation:
“First, there is available in nature an almost
unlimited supply of various kinds of mutations.
Second, the variability within the smallest taxonomic units has the
same genetic basis as…between subspecies [etc]…And third,
selection, random gene loss, and similar factors, together with
isolation, make it possible to explain species formation on the
basis of mutability, without any recourse to Lamarckian forces.”
“…the accumulation of small genetic changes in
isolated populations can lead in the course of time
to a new integrated genetic system, of such a
difference that it thereby acquires all the characters
of a new species, including reproductive isolation.”
(Systematics and the Origin of Species, 1942: 70 & 158; bold added)
Simpson on Schindewolf (1936):
“After having carefully read the paper cited…it seems to me not only
not to lead to some of the main conclusions of Goldschmidt but also
to contradict them. This paper, although a theoretical work
of great importance and value, is also in some
respects, especially where it does approach
Goldschmidt’s conclusions, at wide variance with the
consensus of paleontologists and even with some of
its own author’s other works.” (Tempo and Mode in Evolution,
1944: 58)
In 1949 Simpson continues his rejection of
Schindewolf by suggesting why German scholars
might think differently:
“For some ten years Central Europe and the West
have been separated by a highly effective intellectual
isolating mechanism, only now beginning to break down. This
barrier to inter-thinking virtually stopped the interchange of
knowledge and ideas between the respective populations, within
each of which the development of evolutionary theory continued
independently of that within the other.” (1949, Evolution 3: 178; bold
added)
Simpson continues:
“Isolation has, of course, worked both ways; western students
have been isolated from German scholars as much as the reverse. It is,
however, assumed that readers of Evolution are…familiar with the main
trends in western evolutionary studies during this period. These trends
have been surprisingly uniform. Although using, at times, radically
different data and working in widely distinct fields, [but] western
students have in almost all cases tended toward a
synthesis the core of which is the action of natural
selection on genomes in populations.” (1949, Evolution 3: 178;
bold/comment added)
Evolution is Adaptation writ large, and that’s that.
Smoothly continuous, mostly gradual accumulation of
small mutations producing slight morphological changes
selected to allow the organism to adapt to its everchanging environmental circumstances, eventually
leading to evolutionary change.
“We postulate no ‘new’ type
of selection” (Eldredge & Gould,
1972, p. 112)
Punctuated Equilibria vs Phyletic Gradualism: tempo
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Gould & Eldredge (1977, Paleobiology 3: 143): Punctuated Equilibria
Some of the backlash:
“This idea is…a special case of Wright’s
theory of random genetic drift as a
mechanism for triggering shifts from one
stable equilibrium (adaptive peak) to another.”
“Evolution by jerks!”
“Why do we need a new model when the one
we already have works well enough?”
In order to be a true evolutionist, one must be
entirely neo-Darwinian, and toe the line of the
“synthesis” as conceived by Dobzhansky and Mayr
via Morgan.
The effect was and continues to be the squelching
of alternative thinking - which was alive and well
prior to 1941.
The expectation of DNA translation…
Jacob-Monod experiment (1961): absence (above) vs
presence (below) of lactose
In the period of molecular systematics represented by the
1960s, concepts derived from study of the bacterial
genome were extrapolated to multicellular organisms.
That is: an integrated linear arrangement of DNA, with
integrated DNA triplets (codons) that were translated into
RNA codons that produced specific amino acids that
formed a specific polypeptide.
At the time, this extrapolation seemed reasonable.
Conflation of adaptation and evolution
The extrapolation of bacterial adaptation to
multicelluar evolution
Lenski and Trevisano (PNAS 81: 6814, 1994)
In contrast to bacteria, in which the promoter (noncoding) region is small and up to 98% of the genome
is coding (i.e. results in metabolic activity), in
multicellular organisms up to 98% of the genome is
non-coding (introns, enormous promoter regions, junk
DNA).
(J. Eisen, Current Opinion in Microbiology 3: 475-480, 2000)
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see thi s picture.
G. Ast (Scientific American,
April, 2005)
Confusing Adaptation with Evolution
Conclusion:
•
Adaptation (= survival of species) and Evolution (=
introduction of novelty) must be decoupled
conceptually and thus practically.
•
Use of “evolution” outside its biological context
continues its false conflation with “adaptation”.
•
Social and biological change are different phenomena.
Conclusion:
•
Social change might be conceived in terms of
adaptation - as economists use the concepts
“invention” and “innovation”.
•
Even though we inherited the notion that “change”
and “evolution” are synonymous terms, only
multicellular organisms can evolve.
•
Societies do not.
Conclusion:
•
When one talks about evolution now in Homo sapiens,
one is actually talking about adaptation, or in the Great
Chain of Being sense, an “unfolding” - in this case the
feedback effect of technological invention on
exploiting the mental/neurological properties that have
been there for at least 100 kya, since the first members
of our species emerged.
Thank you for your
kind attention