I agree that biodiversity is a source of joy and education for me, and I'd add that it's also because we know something about ourselves--we know of the insatiability, the psychopathy, and the destructive nature that comes hand-in-hand with classical capitalism. Many of us see our conservation efforts as a necessary opposing force and as a way of saving ourselves from ourselves.

Only two creatures isn't really possible. It isn't even an ecosystem, it's a Game of Life simulation.

Yes, this sounds a lot like a Mars colony.