I wasn't actually thinking in the direction of symbiosis, more of one species acting as a larger social unit, like a pack of wolves or a hive of bees.
I'll finish the F1 league first, simultaneously trying to find the ideal settings for such a sim. At the moment I'm thinking F1 conditions except huge maps with about 1000 veggies, max collision elasticity and medium to high friction. The minimum requirement would be for one bot to alert others if there is food/foes in the vicinity.
I'll start digging up some bots that would fall in this category. I've seen plenty of ant-like bots, Spiral, some fish-scool bots, and there's bound to be more. As long as there is less than 10 bots that fall into this category, I might even run it at the same time.
I might even use the best or most interesting bots to make a really good environmental simulation.