The unsolved problem of the creation and inheritance of organismic forms
In his article: “Radical Constructivism in Biology and Cognitive Science” John Stewart
wrote:
“In Mendelian genetics1, the "genotype" as such cannot be observed directly2: it is a
theoretical hypothesis or postulate3. Differences in genotype are inferred from observed
differences in a phenotypic character; if there are no phenotypic differences, no genotypes can
be inferred. It follows that there is not and cannot be any genetics of a character which is
invariant in the species in question. Thus, genetics can and does explain the distribution of
(for example) blue eyes vs brown eyes in the offspring of particular crosses; but if all the
animals in the population have eyes, genetics does not and cannot explain why there are eyes
in the first place that might be blue or brown. To take another example, genetics does not and
cannot explain why the offspring of cats are kittens which grow up into cats that resemble
their parents.
This is the sense in which genetics is not a science of heredity. The "blind spot" is even more
complete if the character in question is common to all living organisms. Thus, the
phenomenon of autopoiesis - the fact that all living organisms produce themselves by their
ongoing dynamic processes, which we shall examine more closely below - is and can only be
ignored by Mendelian genetics and, hence, by the neo-Darwinian paradigm. It is to be noted
that this is a true blind-spot, in the sense that not only is there a key feature of living
organisms that is not seen; from a neo-Darwinian perspective, it is intrinisically impossible to
appreciate that there is a feature which is not seen. Nevertheless, this lacuna gives rise to a
serious weakness in the neo-Darwinian account of evolution.”
1
In what follows, I shall use the simple term "genetics" instead of referring pedantically each time to
"Mendelian genetics". Note, however, that this carries a risk of confusion: Mendelian genetics is precisely not a
science of the constructive processes of genesis, as in "phylogenesis", "ontogenesis" or Piaget's "genetic
structuralism".
2
Nowadays, of course, DNA can be observed; but the nucleotide sequence of a piece of DNA is not a genotype,
and to confuse the two is a reification which generates grave conceptual confusion.
3
This is not an objection: in physics, all the fundamental scientific objects, such as atoms, quarks, and
electro-magnetic fields, cannot be directly observed as such. It should, however, as a brake on the slippery slope
to objectivist reification.
In this context I also may quote Denis Noble “Neo-Darwinism, the Modern Synthesis and
selfish genes: are they of use in physiology?” J. Physiol. 589.5 (2011) 1007–1015:
“As I have argued elsewhere (Noble, 2008) the main difference between DNA and nonDNA inheritance is simply that one is digital, the other analog. In developing the
organism the 3D analog information is just as necessary as the 1D digital (DNA)
information. Neither is sufficient by itself… Moreover, organisms are not in fact digital
machines (Shapiro, 2005; Noble, 2010a).”
In these two articles the authors refer to a fundamental problem of Biology. Namely,
there is no molecular-biological explanation of how the form of an organism is
maintained (or altered in a potentially useful way) in the constant metabolic flux of
structural modifications. If one does not know that, one cannot explain how a certain
form is inherited. The suggested dependence of a phenotype on a genotype has no sound
scientific foundation, if we infer a molecular basis for the genes in the sequence of
nucleotides (apart from the problem that it is difficult to characterize the nature of the
genotype; I may quote Noble in the article above: “The concept of a gene has changed, and
is still changing, so what version do we use?”). The alleged relation of the phenotype on the
genotype is also misleading because it is based in an unjustified generalization of
Mendelian genetics, in which differences in a phenotype are identified with the
phenotype as a whole (see Stewart, above). For this reason we have to answer the
question how the analog information of a form, mentioned by Noble, is stored and
inherited. Genetics does not give a satisfactory answer, as has been stated by the geneticist
Stewart. Inheritance of specific forms of a species is therefore still an unsolved problem in
Biology. I tried to solve this problem by transferring Whiteheads idea of the interdependence
of actual entities (in which the outcome of antecedent actual entities is “inherited” by
subsequent actual events) to a chronology of intracellular adaptive events.
A molecular-biological explanation of inheritance of a certain organismic form is impaired by
the fact that it is impossible to obtain a molecular model of morphogenesis, for the following
reason:
Firstly, the form of an organism A is what is perceived by an organism B. If, for example, we
could somehow experience the electric field of a fish, we would perceive this organism in a
different manner. A molecular model of how we see the form of an organism must therefore
be loaded with the properties of our highly developed perceptive apparatus. Since the form is
not an objectively given entity which is independent from an observer, morphogenesis cannot
be derived from the metabolic activities. Naturally this problem is a consequence of the
difference between organisms and non-living beings. In the latter case the form is the result of
the arrangement of components, whereas in organisms the structure is constantly altered
although the form is maintained. This means that in organisms the form determines how the
components of its different structures are permanently re-arranged during its development and
not vice versa. In this process a cell or an organism strives for functional harmony of all its
partial processes. Morphogenesis has therefore a ‘geistige’ (cannot be translated, perhaps
psychophysical?) dimension in the sense that it is related to an ideal. This dimension does not
exist in chemistry.
Secondly, there is the problem of ‘autopoiesis’ addressed by Stewart in the quotation above.
To explain this, let us consider the proliferation of the spindle-shaped green alga
Ankistrodesmus. In this case a mother cell divides into several spindle-shaped daughter cells,
the socalled ‘autospores’. Then the cell wall is degraded and the little spindle cells are
released. In the subsequent growth process in which each of the autospores finally becomes a
new mother cell, the shape of a spindle is maintained. The form of this alga is determined by
the cell wall, which is located outside of the cell membrane. For this reason during growth of
the cell the biosynthesis on each position of the cell wall must be coordinated with the
biosynthesis on all other positions, because otherwise the form of the cell would be distorted.
Furthermore, the biosynthesis of the cell membrane, the cytoskeleton etc. must be also
conformed to the enlargement of the cell wall. During growth all biochemical partial process
must therefore constantly and simultaneously be adjusted to the recreation of that particular
form, since an increase of the cell volume requires a permanent reconstruction of its
structures. But this means that the constantly occurring establishment of a certain form during
the development of a cell has a teleological aspect. Thereby, a not yet existing final state
regulates the coordination of all partial processes for re-attaining the intended form by the
organism. Such a coordination, endowed with an anticipatory orientation towards the future,
requires the existence of an internal relationship among all partial processes. For this reason a
coordinating principle is a precondition for maintaining the certain form, by which the cell
distinguishes itself as a unity from its environment. Chemistry does not provide such a
coordinating principle and therefore is insufficient for an explanation of morphogenesis.
In order to deal with this problem I have previously suggested (in our discussion with Salthe)
to consider the organismic nature as a correlate to technical practice that comprises a producer
and its product. The products are the structures, by which the organism constantly re-creates a
potentially useful form during its development. The structures can be analysed and localized
in objective terms. But the producer is a precondition for the creation of objective structures
and therefore, as the creative organismic subject, evades an objective description. Since there
is an ontological difference between a producer and its products, the producer can be found in
the cell by searching for an ontological difference in metabolic activities. In a previous
publication (in “Beyond Mechanism, Putting Live Back into Biology”) I have explained how
this can be achieved by analysing interplay of energy converting processes in the cell. Setting
out from this physiological explanation I have then (inspired by John Dewey) postulated that
the energy flow through a living system serves as a medium for a ‘field of tension’, involved
in anticipatory information processing about a potentially useful reconstruction of energy
converting subsystems. In this process, organismic identity is based on an internal
representation, provided by this ‘field of tension’ that emerges self-referentially from and acts
upon reconstruction of energy converting subsystems. Thus, such a ‘field of tension’ carries
information about the form of a species in the individual development and in a succession of
generations. Therefore the ontological difference between a ‘field of tension’ representing a
general feature of the organism and its partial processes guides the process of morphogenesis.
The ontological difference is revealed in interplay between nascent form and attained physical
form (again better in German: between werdender Form und gewordener Form; for Ernst
Cassirer between forma formans and forma formata). In its form an organism gives itself a
physical expression by which it tries to exert pressure on its surroundings. In higher
developed organisms this is also the basis for bio-communication: in this case an
interpretation of the expression of an organism A by an organism B determines how B
expresses itself in response to this and vice versa. From the sequence of mutual interpretations
of acoustic expressions finally language emerges and, as a result of the collective reflexivity
of the language, higher forms of consciousness (for details of this process see: Ernst Cassirer,
“Philosophy of Symbolic Forms).
Along this line I tried to develop a ‘theory of organisms’, in cooperation with the Swiss
process philosopher Reto Luzius Fetz. It will be published in near future. It is based on some
thoughts of Whitehead, but in order to accomplish this we had to adjust the categoreal scheme
of Whitehead to Biology.