The extent of these appearance-altering abilities and the limits thereof are not entirely clear. According to Rowling, a Metamorphmagus can alter his or her appearance completely, for instance, from black to white, young to old, handsome to plain and so on. In one example, Tonks changes her facial appearance by reshaping her nose into "a beaklike protuberance like Snape's", to "something resembling a button mushroom", and "one like a pig snout" which reminded Harry of his cousin Dudley. The emotional state of a Metamorphmagus can affect their abilities.