are bare single-strand RNA loops of around 300 nucleotides causing
plant diseases. They do not code for protein. The simplest of
infectious agents, viroids would seem to be good candidates for
thinking about the first genetic material.
These rules for the nucleotide game should result in viroids:
These conditions imply that there is some source of the nucleotide
molecules (either new or recycled); and that those molecules are
- Environments are composed of molecules
occupying locations in a metric space with continuous or
- There are an infinite variety of molecules possible.
- Reactions are transformations of molecules in
close proximity to other molecules in close proximity, some of
the resulting molecules being of types different from the
- There are an infinite number of possible reactions having
positive probabilistic rates of reaction.
- Nucleotide elements of polymers spontaneously change at a
low rate compared with the rate of nucleotide replication or
complementation. These changes are called mutations.
- There exist nucleotide molecules which will
replicate or complement a nucleotide polymer (template) under
conditions which occur periodically.
- There are periodic conditions under which the replicated
or complemented polymer will separate from its template.
- A nucleotide polymer species is called
enduring if the probability of it or a replica surviving a
replication cycle (polymerizing and separating period) is greater
than one half. An unbounded number of distinct nucleotide polymer
species are enduring.
- There are periodic conditions under which these
nucleotide molecules will spontaneously bond together, forming or
- Some combinations or permutations of nucleotide molecules
interact with other molecules differently than do other combinations
of nucleotide molecules.
The periods may be continuous and simultaneous. Condition 9
bootstraps the process so there will be polymers to replicate.
Condition 10 guarantees that the genetic information matters; the
arrangement of nucleotides in a polymer effects how it interacts with
Because more than half of them survive, enduring molecules which
replicate themselves will grow to outnumber the polymer species which
don't endure. Certain species of nucleotide polymers will replicate
more easily or have higher survival rates; such attributes will cause
their numbers to increase relative to the others.
Notice that the nucleotide game has replication, competition, and
evolution; all without membranes or proteins.
How will this game play out? Evolution of the
Nucleotide Game continues.
copyright © 2004, 2005 Aubrey Jaffer
I am a guest and not a member of the MIT Computer Science and Artificial Intelligence Laboratory.
My actions and comments do not reflect in any way on MIT.|
|The Game Theory of Life
|agj @ alum.mit.edu