In another thread a fellow who goes by Legendary made some rather derisive comments about a suggestion I once made, concerning making computer programs that purport to model biological evolution more realistic. The suggestion was half serious and half tongue-in-cheek, since it would be impractical.
My argument was as follows: Computer programs that purport to model biological evolution invariably isolate the effects of “mutations” to only those aspects of the “organism” that have a chance of helping the organism approach the desired goal (EQU in the case of Avida, for example). But this ignores an extremely important aspect of modeling living systems.
Random mutations, if they are truly random, will affect, and potentially damage, any aspect of the organism, including its ability to survive and reproduce. The computer program, OS, and hardware represent the features of the simulation that keep the organism alive and allow it to reproduce, but this is artificially isolated from the effects of mutations.
Thus, a realistic simulation would allow the program, OS, and hardware to be affected in a random fashion, just as a real organism’s ability to survive and reproduce would be affected randomly by mutational interference. A mutation might cause an enzyme to malfunction and the organism would suffer an early demise, or it might be rendered sterile, and the beneficial mutations would never be passed on.
Of course, this would not be practical, and each “organism” would require its own computer, but the point should be clear: A simulation can’t just arbitrarily ignore aspects of the reality it purports to simulate, because taking them into account would be likely to result in an undesirable outcome.
As a footnote, I highly recommend reading Eric Anderson’s piece on Avida here.