What does the iris of the human eye do when the light is bright?
Well, the iris changes the size of the pupil so when you are in bright light your pupil will get smaller because the eye will absorb all light striking it. However, when you are in a dark room or place your pupil will get bigger/wider because it has no light to absorb it so your eye wants light. For example think of the pupil trying to look for light so it has to get wider!
