According to laughter research, you're not as funny as you think.
Did you ever make up a joke? Most likely you have not. Learn more on this Moment of Science.
The back of your eye, called the retina, has two kinds of cells: rods and cones. In bright light the cones are what we use, while in dim light the cones are less active and the rods take over.
Laughter research has found that less than 20% of laughter is a sincere response to someone's humor. In fact, it's primarily a social signal.