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Access Research Network
Literature Survey
Origins & Design 17:2
Paul Nelson
Charles Darwin on Social Darwinism
Richard Weikart, "A Recently Discovered
Darwin Letter on Social Darwinism," Isis 86 (1995):
609-611.
For many decades, historians have debated whether Darwin was
himself a social Darwinist, i.e., someone who believed
that human beings were and should be subject to the same competitive
forces acting on all other living things. The debate is sharpened
by the poor standing of social Darwinism, which sanctioned a wide
spectrum of abuses. In 1993, historian Richard Weikart (California
State University) discovered an 1872 letter from Charles Darwin
to Heinrich Fick, a law professor at the University of Zurich,
that sheds new light on Darwin's views of the application of his
own theory to human beings. "It is the strongest piece of
evidence of which I am aware," writes Weikart, "that
Darwin himself believed that his biological theory lent support
to individualist economic competition and laissez-faire economics"
(p. 609). In the letter, Darwin complains that trade unions in
England have insisted "that all workmen -- the good and bad,
the strong and weak,--sh[oul]d all work for the same number of
hours and receive the same wages." But this, Darwin avers,
"seems to me a great evil for the future progress of mankind,"
as it will "exclude competition." Here Darwin departs
from his usual circumspection, Weikart argues, to apply his theory
directly to the social conditions of humanity.
Did Life Begin at High Temperatures?
Stanley L. Miller and Antonio Lazcano, "The
Origin of Life -- Did It Occur at High Temperatures?" Journal
of Molecular Evolution 41 (1995): 689-692.
Arguably the grandest old man of origin of life studies, Stanley
Miller and his Mexican colleague Antonio Lazcano here consider
critically the hypothesis that life began at high temperatures
-- 90° C or more. The hypothesis is based on the argument
that the oldest living things are hyperthermophilic bacteria,
which grow optimally at high temperatures. Miller and Lazcano
allow that while hyperthermophiles may be ancient, they are certainly
not "primitive," and possess metabolic machinery similar
to other bacteria (p. 690). Moreover, although higher temperatures
give higher reaction rates, possibly favoring primitive (inefficient)
enzymes, the price must be paid in "loss of organic compounds
by decomposition and diminished stability of the genetic material"
(p. 691), due to the greater heat. "RNA and DNA are clearly
too unstable to exist in a hot prebiotic environment. The existence
of an RNA world with ribose appears to be incompatible with the
idea of a hot origin of life. The stability of ribose and other
sugars is the worst problem, but pyrimidines and purines and some
amino acids are nearly as bad" (p. 691). Miller and Lazcano
conclude that the special features of hyperthermophile bacteria,
which enable them to survive in high temperature environments,
may be secondary adaptations, and therefore not as ancient as
believed. On that view, "hyperthermophiles are not the oldest
organisms" (p. 693), and a hot origin of life is unwarranted
by the evidence.
Complex Bacterial Regulatory Genes:
Circuits for All Seasons
Carl E. Bauer and Terry H. Bird, "Regulatory
Circuits Controlling Photosynthesis Gene Expression," Cell
85 (1996): 5-8.
Purple photosynthesic bacteria know how to make the best of
any situation. "Many of these organisms," Bauer and
Bird (Biology, Indiana) report, "can obtain cellular energy
from light, inorganic compounds, or organic compounds, depending
on the chemical and physical conditions of the environment"
(p. 5). To do so, however, the bacteria must regulate their alternative
modes of energy production to avoid using the wrong system --
and they do so with a complex battery of gene circuits. "Contemporary
studies involving Rhodobacter capsulatus [a photosynthetic
bacterium] have revealed a remarkably complex circuitry that regulates
expression of photosystem genes in response to alterations in
oxygen tension and light intensity" (p. 5). This handsomely
illustrated review explains the aerobic, anaerobic dim light,
and anaerobic high light gene circuits, stressing their interactive
complexity: all this in organisms that could easily hold a convention
of thousands in the period at the end of this sentence.
Naturalism and its Essential Darwinian
Component
Alex Rosenberg, "A Field Guide to Recent
Species of Naturalism," British Journal for the Philosophy
of Science 47 (1996): 1-29.
Rosenberg, a leading philosopher of biology now at the University
of Georgia, explains the centrality of Darwinism for those philosophers
of science who have taken "the naturalistic turn." Like
the hedgehog in Isaiah Berlin's metaphor of the fox and hedgehog,
contemporary philosophical naturalists know one big thing
"that makes almost everything else coherent" (p. 3),
claims Rosenberg -- and that is Darwinism. "Of all the well-confirmed
theories in modern science," he writes, "it is the one
with most direct relevance for the human condition, human behavior,
and its cognitive causes. If any well-established theory can teach
us about ourselves it is Darwin's" (p. 4). Furthermore, "to
a large extent, Darwinian theory is to be both the model of scientific
theorizing and the guide to philosophical theory because it maximally
combines relevance to human affairs and well-foundedness."
In addition to Darwinism, Rosenberg anchors naturalism in the
fundamental principles of what he calls scientism (science "delivers
the goods" [p. 25], he argues) and the rejection of "first
philosophy" (i.e., epistemology from self-evident first
principles). In Rosenberg's view, all our knowledge must inevitably
wind its way back to Darwinian theory. One would like to see Rosenberg
grapple with Alvin Plantinga's "evolutionary" argument
against naturalism, or with Phillip Johnson's arguments in Reason
In the Balance. Both contend that ultimately naturalism --
when grounded in or conjoined with Darwinian evolutionary theory
-- is self-refuting, sweeping its feet out from under itself,
into complete skepticism and irrationality.
The Enigmatic Origin of Feathers
A.H. Brush, "On the origin of feathers,"
Journal of Evolutionary Biology 9 (1996): 131-142.
"It has been a truism for most of this century,"
A.H. Brush (Physiology and Neurobiology, University of Connecticut)
notes, "that feathers are related to reptilian scales."
Yet, he continues, "the molecular evidence questions the
simple, direct relation of the specialized structures of birds
to reptile scale. I will provide arguments to show that reptile
scales and feathers are related only by the fact that their origin
is in epidermal tissue. Every feature from gene structure and
organization, to development, morphogenesis and tissue organization
is different" (p. 132). Feathers appear suddenly in the fossil
record, Brush observes, as an "undeniably unique" character
distinguishing birds (p. 133). Current approaches to the origin
of feathers, Brush worries, tend to focus "on why
feathers evolved or where feathers came from. At this juncture
neither is as illuminating as to ask how they arose"
(p. 133). Brush examines the protein structure of bird feathers
and argues that it is "unique among vertebrates," with
the "ancestral reptilian epidermal structure...still unidentified"
(p. 131). He concludes: "At the morphological level feathers
are traditionally considered homologous with reptilian scales.
However, in development, morphogenesis, gene structure, protein
shape and sequence, and filament formation and structure, feathers
are different. Clearly, feathers provide a unique and outstanding
example of an evolutionary novelty" (p. 140).
Happy Biochemical Accidents Won't Do
Iris Fry, "Are the Different Hypotheses
on the Emergence of Life as Different as they Seem?" Biology
and Philosophy 10 (1995): 389-417.
What does one need to assume, as a bare philosophical minimum,
to conduct research on the naturalistic origin of life? Iris Fry
(Cohn Institute for the History and Philosophy of Science, Tel
Aviv University) contends that one cannot assume that life
came to be as a cosmic accident or near-miracle, a view held by
Jacques Monod, Karl Popper, Ernst Mayr, and Richard Dawkins, among
others. "Biologists and chemists who claim today that the
origin of life borders on the miraculous," she writes, "...suspend
the scientific study of the origin of biological organization
and create a barrier between biological evolution and the preceding
stages of evolution, as well as between physics and biology"
(p. 399). In short, she continues, they open the door to "Hoyle's
teleological option" (p. 400), and despite their philosophical
commitment to naturalism, imply "in fact, a creationist position."
Scientific progress towards a naturalistic explanation of the
origin of life is only possible, Fry argues, if one assumes "the
continuity thesis," according to which (a) there are no unbridgeable
gaps between inorganic matter and life, and (b) the emergence
of life was highly probable. The continuity thesis is entirely
a philosophical assumption, Fry notes. "The decision to adopt
the continuity thesis is a philosophical one...and does
not depend on the success of a specific experimental program,
nor can it be revoked on the basis of its failure" (p. 393).
To abandon the continuity thesis is simultaneously to abandon
the search for a naturalistic explanation of the origin of life.
Thus, philosophical assumptions and arguments, Fry concludes,
go "to the core -- to the very 'right of existence'"
(p. 414) of the naturalistic research program in the origin of
life.
Vestiges and Non-functional Characters
Daniel W. Fong, Thomas C. Kane, and David C.
Culver, "Vestigialization and loss of nonfunctional characters,"
Annual Review of Ecology and Systematics 26 (1995): 249-68.
Darwin frequently twitted his creationist opponents about the
apparently useless structures of many animals and plants. Surely
an omnipotent creator could do better than this, he reasoned.
Why do some birds have wings too short and small for flight; or
cave animals, eyes that see nothing? The same argument has continued
in evolutionary reasoning right to the present day. One response,
from those favoring design, holds that many apparently useless
structures are only apparently useless: careful study reveals
their proper functions. One can also argue, however, that some
vestiges and non-functional structures are, indeed, non-functional.
Loss of complex biological information is far easier to
explain, on design principles, than its natural de novo
origin (and loss may be expected, given certain environmental
changes, such as isolation of a population in a cave). In this
useful review, Fong et al. cover a wide of range of examples
of the reduction or loss of characters, including flightlessness
in birds and insects, eye and pigment reduction in cave animals,
loss of hearing, and decay of specific behaviors. While some of
the discussion should be approached with caution (Fong et al.
discuss the famous 1980 "hen's teeth" experiment, for
instance, without noting that the experiment is now held in some
doubt), this review helpfully summarizes a large literature.
Copyright © 1996 Paul A. Nelson. All rights
reserved. International copyright secured.
File Date: 11.14.96
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