Hooray!! I totally love the way 'Brassica' vegetables provide such a vivid illustration of the amazing variety that some selection-pressure can yield on the development of essentially a single type of input organism. Makes you wonder what might happen when these types of selection-pressures start affecting humankind more!
Brassica and domesticated dogs diversified because of controlled breeding. Unless you get a bunch of totalitarian eugenicists with differing goals, I dont know how this could happen with people.