Despite what you've learned in school, eye color in humans is not controlled by a single gene. It's controlled by two genes. One gene produces pigment, and a second gene controls whether or not the pigment is deposited into the iris. People who are dominant for both will make and deposit color and have brown eyes (green, amber, etc, depending on the alleles for pigment that the person has). People who are dominant for the first gene will make color, but if the second gene is recessive, the pigment will not be deposited and they will have blue eyes. People recessive for both neither make the pigment nor deposit it, even if they had pigment around - they have blue eyes too. What is the name of this phenomenon