And now for something completely different...
Give it a few time steps to settle down, but what you will soon see is
everyone active, then red (inactive) ants appearing on the edge.
Eventually the activity will shrink down to the middle and perhaps die
away. But very soon after, one will become active again and you'll see
the wave of activity spread until everyone is jumping. If you were bored
enough to count the number of timesteps the 'ants' are active, you'd find
it's very nearly the same every time. That means, periodicity! An
emergent property of the individual ants.
Here is a graph of activity versus time for this, in which the periodicity
is very evident.
Now this is the most
rudimentary intro to this. There are
five parameters that vary continuously and grid size and geometry and ant
density can all be changed.
On top of that, this can be done by having each ant driven by a chaotic
oscillator, getting rid of the random activator, which pleases the
deterministic nonlinear dynamicist in us all.
[Here's the java code.]
You are free to use and modify it.