Back in the 1990s I spent a long time playing with Tierra (https://en.wikipedia.org/wiki/Tierra_(computer_simulation) ) and actually wrote my own distributed version[1] so it could run over multiple machines (computers were really slow back in 1991), and a simplified instruction set. Now I know that Tierra has a number of serious shortcomings compared to real evolution. Nevertheless it does really surprising things if you let it run long enough and then examine the cells that evolve in the system. Some cells become parasites, some become really large. I also saw really surprising optimizations happen spontaneously that I wouldn't have thought about.
Anyway given that the real thing has been running for 3 or 4 billion years, I'm not surprised that it has generated incredible complexity.
Anyway given that the real thing has been running for 3 or 4 billion years, I'm not surprised that it has generated incredible complexity.
[1] http://oirase.annexia.org/dlife/