I gotta say, this is an interesting idea. I don't know if I can join myself, since I have a hectic schedule and can't really post regularly. :dreamy

In any case, am I right in summarizing that basically the animals mutated to humanoid creatures and after a period of time they banded together to avoid from being eradicated by human? 
I'm curious, what would the animal kingdom settlements be like? In the wilds like cavern, on trees, underground and such, or would they build houses like humans do? 

You mentioned about cats, dogs and insects, how about the avian? Maybe some of them mutated to harpy like creatures or like human with wings (I'm thinking like Hawkgirl from the comic) ? :cool

Err... sorry for the barrage of questions. .__."