For those who just don't want to evolve out of the primordial slime, is it possible to just stay a microbe?

Of course to get the full benifit of the game, my microbe army will develop thriving civilisations, with advanced technology like all those other multi-cellular organisms that think they're better than us microbes.

They will feel the wrath of our doomsday device... or maybe just a runny nose - haven't decided yet.