Date sent: Sun, 23 Jan 2000 17:26:55 -0500 (EST)
From: Robert Bradbury <email@example.com>
Subject: Complexification of life [was: Selfishness]
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> On Sat, 22 Jan 2000, Joe E. Dees wrote:
I didn't write this; I just inserted some book references.
> > I believe Robert Owen wrote:
> > >
> > > The basic question asked is: why is their not nothing but unicellular life
> > > on earth? Why are we not all bacteria?
> > >
> > > What needs to be explained, in this view, is what would cause quint-
> > > essentially successful unicellular organisms to form communities and
> > > eventually a differentiation of labor in the development of multicellular
> > > organisms such as ourselves. Whatever the cause, the effect obviously
> > > had survival value.
> Precisely. Forming multicellular organisms changed the scale at
> which you could operate, therefore opening up new ecological niches.
> Consider the race to "get big" in trees. The higher you go, the
> more sun you get. Now, the transition to complex cells was driven
> mostly likely by the difficulty of transfering large gene complexes
> of naked DNA between bacteria. Better for one bacteria to "get big"
> and engulf another one in its entirety (leading to mitochondria
> and chloroplasts). The problem is that once you are "big" you
> have to develop better partitioning systems or active transport
> to keep the diffusion of molecules in a very large space from
> slowing down your growth rate. Even then the added complexity
> gives you headaches (bacteria replicate in an hour or less, eukaryotic
> cells take 18-24 hours).
> I think calling all of this "cooperation" may be stretching it
> a little. We would have to nit pick on the difference between
> cooperation and symbiosis. Particularly when the symbiosis
> may be required for the survival of both "organisms", while
> cooperation perhaps is not.
> Generally, I would agree that the rise of social cooperation has
> some similarities (cooperation between people changes the scale at
> which you can "operate", opening up new niches in which you can survive).
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