I would like to end on a personal note: one thing has always struck me in the organization of the most remarkable utopias of Western literature, and that is the total absence of animals (Lestel 2002:62).
I guess he doesn't mean Dinotopia...
In any event, I also find that interesting. The one exception I can think of offhand is the "Gaia" planet in Asimov's Foundation series, which is pretty explicitly organized along biosemiotic lines, although with the addition of some kind of "superphysical" element (even inanimate objects like mountains are capable of contributing to the "planet-mind" in this utopia). And that makes a strong contrast to the Foundation, which is entirely organized along rational lines, and doesn't -- as far as I can recall -- have any mention of animals.
I'd be interested to make a list of others, if anybody can think of any.
Lestel D. 2002. The biosemiotics and phylogenesis of culture. Soc Sci Information 41:35-68. Abstract