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In this paper a model for body formation is proposed, to a …
Biology Articles » Evolutionary Biology » An Effort to Explain the Process of Body Formation » Chapter 8
According to the hypothesis of mine, after the level rise there are at the cells of normal bodies
not the same situation at hand as at the slime molds. Any division of cells does not take place
at that stage. Here there is occurring a development of the same kind as at the slime molds.
Different modes of behaviour are being developed, depending on the position of the cells
within the body. As is the case with the slime molds, all cells are mastering the same set of
Accordning to my hypothesis, these behaviours are the origin to the different subprograms
that, after the DNA has begun functioning, together are forming a complete body during the
fetus development of normal bodies.
From Bonner  I have picked up that the very first stage of the development at animal fetii
are characterized by a period, when the different parts of the embryo have the same potential.
And Lennart Nilsson and Lars Hamberger  write the following: “If examining the surface
of the perikaryon (cell body) carefully, one can observe that almost no cell looks lika any
other.” This is what is used to be called cell division. Up to a number of eight, they are all
similar and do all the same thing. “How does then every cell then know what it shall become
and to which organ of the body it shall belong? Herein is still one of the great mysteries of life
embedded…” (I am here citing the text. It has since 1990 been shown that the number of cells
usually is 16).
The level rise of normal bodies is likely occurring momentarily, as well as in the case of the
slime molds, but that is not equally observable. What has caused the level rise of normal
bodies is difficult to know.
This territory phase of the slime molds, with numerous cells, corresponds in the case of
normal bodies apparently to a few cells before their level rise. I am here referring to the figure
in chapter 6. What I believe I have succeed in explaining with respect to the slime molds in
phase one ought - in spite of the differences in the other respects- to be applicable upon the
few cells of the normal bodies during phase one until the level rise. Phase one constitutes a
lower level than phase two and the cells of phase one are biological individuals and, hence,
object to the environmental pressure. Furthermore, in both cases holds that the cells before the
level rise are identical and both contain the whole program for the following body formation.
At the slime molds it does therefore not take place any cell division after the level rise and the
body formation does not use identical cells and these can neither be physically changed after
the level rise. A change of the physical status of the cells is, as far as I can understand,
possible only in the case of cell division ruled by the DNA. By this reason it is only
behaviours that can be developed here. According to the hypothesis of mine, all the cells have
in their program a common pool of the behaviours required for the different parts of the slug.
The program can be thought of as an inner plan for the build up of the slug according to which
the cells are enforcing the different behaviours that are being needed in the different states of
the slug. As Ardray writes: “Around a founder cell others will bunch in a growing aggregate,
clinging together until they have formed a sausage-shaped slug visible to the naked eye”
and these have become
its simple functions. The whole development has gone very
- * -
The following discussion is intended to clarify the comparison between the different bodies:
A population is a necessary prerequisite for a level rise, since it means that an amount of
lower organisms is forming a higher organism ruled by a superior function. Therefore in
normal bodies first some cell divisions must occur in order to let a population arise that can
perform a level rise. The minimal amount of cells in a population will therefore be two, which
I find is lowest possible. In that case we know that it is a question of about eight cells within
the population of normal bodies before the cell differentiation.
That means that at the starting point for the level rise it is a conformity between the slug case
and the normal case – the level rise of both of them is beginning with a population of normal
cells that all is carrying the whole program.
Why must the eight cells be identical, not only in a physical sense, but also with respect to the
program? Yes, the starting point is a cell that is carrying the whole program. In connection
with the cell divisions that thereafter have occurred during faze one there is no opportunity for
those eight cells to have been differentiating themselves with respect to the program, since
they belong to phase one and there they can not have been involved in the program that has to
be realized after the beginning of the level rise (cf. picture in chapter 6). Hence, all the eight
cells are carrying the whole program after the level rise. But each of them can only fulfil some
parts of it, just as the slime molds have whole their behaviour program but can only fulfil the
parts that are corresponding to their position on the future body.
Here it is a question of a situation that with respect to its consequences corresponds to the
“clinging” slime molds that from its total program is activating the behaviours, which is being
required at every position on the future slime mold. That shows that in those respects there
would be an analogy present between the both systems for body formation, implying that the
eight cells chose to fulfil different parts of the total program. The answer to the question that
was being cited above – “How does then every cell know what it shall become---“ would then
be: Before the level rise the cell does not know what it shall become. That is being decided
after the level rise..
The eight cells are then in the same situation as the population of slime molds were after the
level rise, but the continuation must be different due to the different preconditions. The
difference is among others that the eight cslle now is beginning a long development through
cell division, ruled by the DNA in chronological order.
For both the slug and the normal body it seems to hold that they are beginning with a selfish
cell, that the body formation is initiated from a population of selfish cells and that the final result is a body on a higher level. And so it is working not only the first time. It is being
repeated in every new generation; always this change at the cells from selfishness into
altruism (or chemical operation control) in connection with the body formation. The
participating cells are responsible for the level rise under the influence of the development
forces and they are biological individuals; after that they are included in a selfish body and are
being ruled by a superior function and they are altruistic or chemically managed.
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