such as "Introduction", "Conclusion"..etc
According to Gould  there are only two established scenarios for body formation, but
regrettably neither has been treated exhaustively. In the first scenario, called “the melting”,
one group of protist cells were brought together. They began to live as a colony, developed a
division of labor and developed finally an integrated structure.
In the second scenario, called “the section”, there arose cell departments within one sole
protist cell. (A third conceivable scenario, repeated inability at the daughter cells to part after
the cell division, has nowadays few proponents.)
I have not been able to comment the above as I am lacking the relevant knowledge. But I can
barely believe that the problem body formation would be solved according to these guidelines.
- * -
In ‘The Ideas of Biology’ by John Tyler Bonner, p. 25, the transformation into
multicellularity. “Why did single-celled organisms become multicellular? Why is it, if some
groups found the unicellular existence so permanently advantageous, that all groups did not
stick to it? The answer probably lies in the matter of the increase in size. Larger organisms
can do things that are not possible for smaller ones; they live in different ways, and by
becoming large a new world with new opportunities opens up. (…)”
Among the living multicellular organisms we find an abundant variety of different and from
each others separated endeavours to increase the size.
That is interesting but does it not mean that the transformation to multicellularity also is being
urged on by these efforts for larger size; behind the transformation into multicellularity there
are presumably other causes.
Bonner describes further additionally on p. 121: “Put in another way this means that
originally a multicellular organism was a collection of unicellular organisms that were
physically attached, but eventually, through selection and the need of improved efficiency of
function, the division of labor became marked so that the individual cells were no longer
separate organisms but part of a new, larger, and more complex organism. If one were to examine cell colonies that exist today among the algae, the protozoa, and other aberrant
groups, one would find every intergradation from groups of individual unicellular organisms
that seem accidentally stuck together to well-integrated yet primitive multicellular organisms.
This kind of observation leads to the old question of what is an individual, and the answer
seems to be that there is no sharp division line between a group of cell individuals merge to
form a true multicellular individual; there is a continuum between the two extremes.”
On p. 28  Bonner writes: “The more successful method of increase in size is to have a
series of cells stuck together in a true multicellular organism. But even this can be done a
number of ways: the cells can divide and the daughter products fail to separate, or there can
be an aggregation of separate cells. Only the former has given rise to higher animals and
plants while the latter is found, for instance, in a curious group of organisms called the
cellular slime molds. Here amoebalike cells grow first, and these aggregate into cell masses
after they have finished feeding.”
He thereafter describes the following process that strikingly resembles the behaviour of the
slime molds of Ardray.
Any viewpoints upon the causes behind the body formation is not being given, except for the
striving for increased size respective a development regarded as passing continuously from
simple cell clusters into primitive multicellular organisms.
The statements that Dawkins has recorded give more motivated explanations to the body
In “The Selfish gene”  is among others following stated: “Both animals and plants
evolved into many-celled bodies, complete copies of all the genes being distributed to every
cell. We don not know when, why, or how many times independently, this happened.”
Some authors use to use the parallel with a colony and are naming the body a cell colony.
Dawkins himself prefers to think of the body as a gene colony and the cells as comfortable
and practical working units serving the chemical activities of the cells.
Even though the organisms are gene colonies, they have undisputedly attained their own
individuality with respect to their behaviour. An animal moves as a coordinated whole, as a
The selection has favoured such branches that are cooperating with others. The intensive
competition must have rewarded central coordination rather than anarchy within the common
body. Nowadays the intricate, mutual co-development between the genes has gone so far that
it is no more possible to identify the individual machine of survival due to its collective
properties. Practically, it is generally most comfortable to approximately regard the individual
body as something that “tries” to increase the amount of all its genes for future generations.
And in “The Blind Watchmaker’ : “It seems that, once the eukaryotic cell had been
invented, a whole new range of designs became possible. Most interestingly from our point of
view, cells could manufacture large bodies comprising many billions of cells”.
“A major step in evolution was taken when cells that had been produced by successive
splittings stuck together instead of going off independently. Higher-order structure could now
When reading the accounts of Dawkin I find rather much worthy commenting. The constant
picture is that the development from cell to body is described as free from conflicts, almost
always occurring almost by itself.
The idea of a cell colony is very close and seems to be the closest one can come concerning
the active forces within a body. The word ‘cell colony’ gives an apparent impression of clarity.
But it is impossible to derive sufficiently strong forces from the colony concept that are able
to account for development and reproduction. A colony is a phenomenon that is lacking a
suffient identity of its own.
Proposals to replace the concept ‘cell colony’ with ‘gene colony’ are a track that can lead
wrong. The cells are something more than working units for the chemical activities of the
genes. It is the cells and not the genes that are actively being involved in the level rise process.
The obvious starting point for the solution of the problem of body formation has been the
doctrine of evolution. Therefore it is often being spoken about that the selection has favoured
genes that are cooperating with others and that the intensive competition has favoured central
coordination to anarchy within the common body.
That there exist cells and bodies everybody knows. It seems therefore natural so imagine that
“it only happens” when a body is forming. The problem is not visible.
The hypothesis of cell colonies is hence not completely satisfying; it does not contain any
explanations why, it is only question of giving a name, a heading to an unexplained
Any hypothesis about how the body formation might have come about is accordingly not t be
found in the account by Dawkins, but only notions about cell colonies and an effort to apply
the doctrine of evolution upon the problem of body formation. But that way is, as I have
shown earlier, not practicable.
Copyright © 1992: Per Olof Jonson, Bandhagen
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