[AndrewC]

No, as I understand mutations there is never stability, per se.

Gee, are you now arguing on my side? Read what I have written. That little realization then makes one wonder why anyone could think that something complex could ever evolve. Simulation programs that "prove" evolution always have a non-moving target as the goal. They never have a varying goal. For instance the target chosen by one is "Methinks it is like a weasel" which never changes, not:
methinks it is like a aardvark,
weasels are like otters,
methinks it is like a vessel,
wethinks tis like a weasel,
as the goal at various times.

Having a varying goal results in chaos for these programs.

[CobaltBlue]

That little realization then makes one wonder why anyone could think that something complex could ever evolve.

Not when I consider the truly immense length of time involved. Compare it to the movement of continents and the formation and erosion of mountains, that's the kind of time scale we're looking at.

Having a varying goal results in chaos for these programs.

We can't even properly model weather in real time yet, so I don't expect to be able to model evolution in four dimensions yet.

[Nebullis]

Simulation programs that "prove" evolution always have a non-moving target as the goal. They never have a varying goal.

For lurkers, simply google on evolutionary or genetic programming with dynamic fitness.