Normally the predator species would evolve quite quickly (first 1000 generations) but this world goes to 50,000 generations and we never see it.
The difference is a change I made. It's clear that predation relied on a feature I just removed: When a creature attacks they steal a certain amount of energy from the creature they attack. Normally the amount of energy is a function of how much energy they already have (I was trying to model the idea of being able to eat more because you're bigger). In this world, I made it a constant (20 energy).
In retrospect, I was foolishly doing something I said I wanted to avoid: allowing the agents to be functionally different in any way. I want them to compete on brain power alone.
But it does make me wonder if somehow forcing them to compete on brain power will actually result in a less complex and less advanced world. Luckily, I have a simulator to test such things. :)
First then, I'll try to generate speciation without allowing them to be functionally different in any way; I'm going to modify the terrain. Some places will be harder to move over. Some will have less food. We'll see if that causes it. (The simulation for this is running now)