I live in a canine-friendly town where people are allowed to bring their dogs into stores with them, which gave me the chance to meet this gorgeous one-or-two-year-old female Lab-pit bull mix. Aside from her pretty brown-and-white coat and long, lithe body, the striking thing about her is her differently colored irises. This characteristic is called heterochromia, and according to Slatter’s Fundamentals of Veterinary Ophthalmology, it’s caused in dogs by incomplete maturation or absence of pigment granules in the iris stroma or anterior pigmented layer.





















