As seen through the eyes of an iguana the world seems very colorful.  Iguanas associate the colors with their food most of the time.  Some say this is how they tell the difference between good food and bad (poisonous) food.  They also can tell the difference of the people they interact with.  Iguanas have image feedback that shows them something that they have seen in the past.  Iguana eyes narrow just like a cat's eyes only to say "I'm aware of my surroundings." The iguana's eye widens only to say "I'm scared and you need to back away." Then their eyes can be half narrowed and half widened only to say "I'm happy with life!" So the eyes of an iguana are very important and should be taken care of so the iguana can live a full and happy life.