The percentages of people with various eye colors are unknown for many countries. However, according to the American Academy of Ophthalmology, 32 percent of Americans have blue or grey eyes; 15 percent have blue, grey or green eyes with brown or yellow flecks; 12 percent have green or light brown eyes with minimal flecks; 16 percent have brown eyes with dark specks; and 25 percent have uniformly brown eyes.
Unlike many other traits, a simple gene does not determine a person’s eye color. Accordingly, the pattern in which eye color is inherited is complex. Brown eye color is generally dominant over green and blue eye color, and green eye color is dominant over blue eye color. However, because many genes are involved in the process, blue-eyed parents can produce brown-eyed children.
Contrary to popular perception, human eye color is quite complex, and people have a variety of different eye colors. Rather than only occurring in blue, green and brown shades, many intermediate colors are recognized. Additionally, some people have eyes of more than one color.
Different eye colors dominate in different geographic areas. For example, blue eyes are very common in some European locations, while brown eyes are more common in Africa and Asia.