Okay, so there could be one more rare exception. Do a search on here for Gynandromorph. There are a few people that have had chickens that are male on one side and female on the other. Some will both lay eggs and crow. They are not hermaphrodite. As I understand it, in chickens all cells are either male or female cells. Sometimes it happens that they are split down the middle with one half the body being female and one half male. If this is the case, you may see a difference in feathering on one side of the chicken from the other, although not as dramatic as if you stuck half a rooster and half a hen together (if that makes sense). It's rare, but it happens. Check it out.
