User blog comment:TheNewProtagonist/Let's talk about the Grimm/@comment-68.226.106.213-20131014040315

(This is gonna be a LONG comment)

We know there are sloths, since Nora mentioned them. And we definitely know there are wasps, because Cardin asked Jaune to catch some and brought them to Forever Fall. Presumably, there are dogs, cats, birds, fish, reptiles, frogs and maybe dinosaurs (if RWBYRex becomes an official character).

Presumably, the Grimm are like Star Wars rakghouls: they CAN breed, but they can also infect other creatures. The reason: if hunters were able to kill as many as Ruby did in the Red trailer, the Grimm would most likely be hunted to extinction very quickly. Unless there are Uber-Grimm stronger than whole armies of hunters. Then I think the Grimm have some breathing room.