```This is just off the top of my head. I thought I'd post it instead of
emailing, in case people want to discuss it and/or think about it.

This is "life" in a sense, but not John Horton Conway.

Imagine you have N lifeforms to start with, each with a certain
genotype. For simplicity, we could assume simple dominance, no
sex-linked traits, and panmictic mating (probability of mating is
random based on the population). Purists out there: Please don't
flame any slight misuse of terms unless it's really relevant.

Flashback to the first day of Genetics 101:

AA = homozygous dominant
Aa = heterozygous
aa = homozygous recessive

The population's genotype frequencies are obviously
pAA + pAa + paa = 1

A few seconds of thought should show that the gene frequencies
are
pA = pAA + 0.5pAa
pa = paa + 0.5paa
and also
pA + pa = 1

I imagine modeling each individual as an object running in a
thread. For the heck of it, give each individual a location in
a grid. Let them wander around. When a nature male bumps into a
mature female, a probability function determines whether they mate
and how many offspring they have.

Assume each individual has a known average lifespan and a typical
mating age. (I'd favor expressing these in millisec for purposes
of the simulation). Let the "children" have certain probabilities
of surviving to mating age: qAA, qAa, and qaa. Typically, these
are all near 1.0 -- in many situations, the heterozygote will be
a little less likely to survive, and the homozygote least of all.
(This is the trivial case in which "A" is good or healthy and "a"

All things being equal, such a population will eventually reach
what is called Hardy-Weinberg equilibrium, in which the genotype
frequencies reach a constant and stay there (for a suitable value
of epsilon).

Run the simulation with large numbers of individuals. Sample the
population once in awhile and check the numbers. Watch for
equilibrium.

Write a pure deterministic (algebraic) model that will predict when
equilibrium occurs. See how well it matches your simulation. An
iteration in the deterministic model is simply a "generation" -- I
think we can consider that equal to a lifespan (or perhaps, hmm, the
lifespan minus the mating age?).

Just a thought...

Hal

```