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The Cancer Journal - Volume 10, Number 1 (January-February
1997)
Neo-darwinism - Darwin's theory of evolution was the most important theory
of biology in the last century. Its updated version is known as neo-darwinism.
Today neo-darwinists have virtually taken over the philosophy of biology, claiming
to be even better than Darwin himself: "although Darwin's own articulation of
his theory was monumental, . . . there really were very large gaps in his theory
that have only recently begun to be properly filled in. The biggest gap looks
almost comical in retrospect, without which the theory of evolution is hopeless:
the concept of the gene. Darwin had no proper unit of heredity. . "(1)
( p. 20). So Darwin has been rescued by neo-darwinists, who provided the
gene, making his theory respectable. Then: "In a single stroke, the idea
of evolution by natural selection unifies the realm of life, meaning, and purpose
with the realm of space and time, cause and effect, mechanism and physical law".
(1) ( p.21). A new gospel is born, a theory of everything, that claims
to undermine even religion. Its latest account, "Darwin's Dangerous Idea" (1),
was written by Daniel C. Dennett.
A fascinating book, written by an ardent devotee, who vehemently attacks his
opponents, such as Chomsky, who argued that science has limits and that some
of the explanations of neo-darwinism are no more than a belief, and may
be irrelevant. Or Gould and Lewontin, who call adaptationism "Just So Stories".
Dennett overwhelms his readers with many more "Just So Stories", e.g.,
natural selection as an algorithmic process, or that life evolves in a design
space. These fascinating ideas highlight the major conceptual flaw of neo-darwinism:
it does not distinguish between observation and speculation. Darwin illustrated
his theory by metaphors, and his followers took them as facts.
Darwin attempted to explain the prolific diversity of life-forms and their complexity.
This diversity might have been created as such, (Genesis), or it could have
evolved, as proposed by Anaximander [546 B.C.]. He believed that all
things come from a single prime substance. Worlds evolve and so do animals.
Man and animals are descended from fishes (2). Darwin
maintained that the different forms of life had developed gradually from a common
ancestry, and that the driving force of this process was the struggle for existence
and the survival of the fittest. Life-forms proliferate exponentially and compete
for the same living space. Since resources are limited, only the fittest survive.
For neo-darwinists like Dennett, this is the only explanation possible: "Could
anyone imagine how any process other than natural selection could have produced
these effects?" (1) (p.47).
Web of life - Darwin's theory applies only to a
small fraction of life: animals and plants. It ignores the microscopic
world whose biomass is much greater than that of macroscopic life. "It has
been estimated that the top 6 in of fertile soil may contain more than 2 tons
of fungi and bacteria per acre." (3) ( p. 715). "The
metabolic potential of the microorganisms in the top 6 in of an acre of well-fertilized
soil at any given instant is equivalent to the metabolic potential of some tens
of thousands of human beings" (3) (p 716). Microorganisms dominate the oceans
where the macroscopic world is even less abundant than on land. They dominated
the earth for 3.5 billion years, and prepared our planet for the evolution of
macroscopic life as witnessed by Darwin (4). Their
outstanding achievement was the maintenance of oxygen and carbon dioxide in
the atmosphere, without which life would not have evolved. They established
the ecological web, made of complex food chains, within which animals and plants
evolved (5).
Solar energy trapped by chlorophyll-containing organisms, e.g., algae and plants,
is converted mainly into cellulose, which is indigestible by most higher life-forms,
who lack cellulose degrading enzymes. Cellulose is degraded solely by microorganisms.
Microbes and degradation products are ingested by protozoa. These in turn are
ingested by higher life-forms and so on. At the high end of this food chain
are the animals which serve as our food.
Gaia - All this was unknown to Darwin and is still
ignored by neo-darwinists. Life has evolved and still evolves as a complex
web, called by James Lovelock, Gaia (6). "A self-regulating
entity with the capacity to keep our planet healthy by controlling the chemical
and physical environment". Gaia is a biosphere that controls itself. An ecosystem
in which life and its environment are coupled. It was born in the "primitive
soup", has been evolving ever since, and we differentiate in it (7).
All this is not accounted for by neo-darwinism. Evolution theory is a drastic
simplification of this complex process. A poor theory that should be augmented
to account for the web of life, or replaced by a better one.
1. Dennett DC. Darwin's Dangerous Idea. Evolution
and the Meanings of Life. Simon & Schuster Inc. New York., 1995.
2. Russel B. A History of Western Philosophy. Simon
& Schuster Inc. New York., 1972.
3. Stainer RY, Adelberg EA, Ingraham JL. Microbial
World. 4th ed. Prentice-Hall Inc. Englewood Cliffs, NJ. 1976.
4. Atlas RM., Bartha R. Microbial Ecology. The Benjamin/Cummings
Publishing Co. Inc. Redwood City CA, 1993.
5. Zajicek G. Antibiotic resistance and the intestinal
flora. The Cancer Journal 9: in press, 1996.
6. From Gaia to Selfish Genes. Barlow C. Editor
The MIT Press Cambridge MA, 1991.
7. Zajicek G. Evolution theory from a new perspective.
The Cancer Journal 6:178, 1993.