OH, OH, OH NINTH GRADE SCIENCE IS COMING BACK TO ME. Um. From what I've seen, when a black and white swan mate, the babies come out either white or black. I'm PRETTY sure.

I tried to remember something about what that says about their genes (as in, a certain "type" of gene would mean mixing the white and black to produce grey, and another type of gene would mean it has to be one or the other), but I couldn't. lol high school drop-out.