The most common error of the previous AIWorlds were what I call 'stagnation'. Essentially, agents stop choosing to move, attack, replicate, or really do anything. The population just sits there. Every one of them.
AIWorld6 seemed to be an exception. Initially, worlds would run for >10M iterations and would stay lively. And then I found a bug. Specifically, the mutation rate was being set to 0 for a large percentage of the population. The recent evolution of predator/prey relationships was made with a world that started with the error and then the error was corrected to allow mutation again.
After correcting the error, I'm seeing stagnant worlds every time when I set the mutation rate to 0.01. Just now I tried setting the mutation rate to 0.001 and that world lasted 10M iterations.
It's clearly time to test this and find more about how and why the mutation rate affects the world's stagnation.