So if that’s true—as weird as it is—wings, horns, or neither, are probably genetically determined, much like gender. I wonder if their coat and mane color is, too.  Perhaps the foal I saw at the hospital had the white nurse as her mother, and maybe a dark-colored pony as her father, or even the doctor  . . . or is the coloration more complex?  And what purpose would such a wide variety of hair color serve, anyway?  How could that have come about?