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selection. If we take this further, it means that natural selection is
involved,
via
cell structure, directly in ontogenesis, and not just
in evolution. Natural selection shapes cell structure which, in turn,
sorts interactions which are by themselves random, between non-
specific molecules. This process of selection allows ontogenesis to
occur.
Extending the scope of Darwinism in this way obviously upsets
the current synthetic theory of evolution (Mayr and Provine, 1998;
Huxley, 1942), where ontogenesis and evolution come under two dif-
ferent mechanisms. Natural selection is only involved in evolution
via
the mutation of genes which, in turn, determine ontogenesis. The
hypothesis that we are advancing, a concept which clashes with our
usual mode of thought, is that the two processes are produced by a
single mechanism (Fig. 14). Instead of being the result of a deter-
ministic mechanism controlled by the genes, ontogenesis is under-
stood to be an intrinsically probabilistic process, as the stochastic
interactions between molecules are subjected to selection by the cell
structure, which is itself selected by the organism's environment.
In actual fact, the idea of ontogenesis resulting from selective
Darwinian rules is not absolutely new. In Antiquity, Empedocles
(490-435 B.C.) also resorted to a mixture of chance and selection
to explain it.
31
In the 19th century, Roux wrote a topic called
Der
Kampf der Theile im Organismus
[
The Struggle of Parts in the
Organism
] (1881) in which he suggested there was a phenomenon of
Darwinian competition between the components of the organism.
This theory remained largely unrecognised and Roux abandoned it
to adopt a deterministic point of view instead. In the 20th century,
Darwinism was applied to other applications in specialised areas of
biology. In immunology, antibody synthesis is the result of a selec-
tive mechanism in which the variability of the genes that make the
antibodies means that each immune cell synthesises a different anti-
body. The antigen only stimulates multiplication of the cell synthe-
sising the antibody that neutralises the antigen itself (Jerne, 1955).
31
The Fragments of Empedocles are published online at: http://philoctetes.free.fr/
empedocle.html. See fragments 57-61.
