Hey, I got to thinking recently, if the classic fantasy races, like elves, dwarves, goblins, orcs, etc., were all subspecies that branched away from mankind at some point in our evolutionary history, how long would such a process take, and what environments would be likely to produce the traits usually associated with each fantasy race? What advantages would said traits, like elvish pointy ears and slender builds, for instance, provide, anyway?

How physically divergent could the races get before producing fertile offspring with each other is impossible?