A closer look
Blue eyes don't actually contain any blue pigment, they are simply brown eyes with a lack of melanin in the front layer of the iris, causing light to scatter and reflect back as blue in the exact same way the sky appears blue; this structural coloration means every blue-eyed person on the planet shares a single common ancestor who developed this genetic mutation thousands of years ago, giving them a very fancy, scientifically complex excuse for why they are so incredibly sensitive to the glare of the sun during slightly overcast afternoons
