The animation at the bottom of the page is a simulation of an evolving system with plants( green dots), worms( red dots) which can die, respawn, prey and reproduce and birds(blue dots) which can only prey.
Every species has its particularities, with worms being able to hunt one tile in all directions and needing energy( which it gets by eating plants) in order to live and reproduce, or with birds only being able to hunt in a specific direction but with a much longer range.