Eyes changing colour?

Question

Random times of the day, my eye colour changes from green - to brown - to black, what causes this?

Answer 1

first of all, no1 can have black eyes. its just dark brown. and its probably the lighting in the room.

Answer 2

My eye color changes too. From green to blue to brownish/greenish/goldish.

I have no clue what causes the color to change, but I notice mine changes with the climate, the colors I am wearing, my mood etc.