Remember the guys from the Original Star Trek episode, "Let That Be Your Last Battlefield"? You know, Bele and Lokai, the ones who were black on one side and white on the other -or- white on one side and black on the other; muleheaded bigots, hell-bent on destroying each other.
Pretty far fetched concept, right?
Maybe not so much. This does happen in nature!
Isn't nature amazing?!
Now all we need to do is find a lobster who is green on the right side and red on the left, and we'll have ourselves a bigoted doomsday duo.