Why do blue eyes happen because of the Tyndall effect?

An optical effect called the Tyndall effect explains the appearance of blue eyes, green eyes, and hazel eyes. Neither blue nor green pigments are actually present in the human iris. Instead, structural color results from light scattering by the turbid medium in the stroma of the iris.

What we know

• An optical effect called the Tyndall effect explains blue eyes. [3]
• Eye color is determined by iris pigmentation and the frequency-dependence of light scattering by the turbid medium in the iris stroma. [4]
• Neither blue nor green pigments are present in the human iris or vitreous humour. [4]
• The appearance of blue, green, and hazel eyes results from the Tyndall scattering of light in the stroma. [4]

Where to go next

• compared withWhat is Rayleigh scattering in the sky?
• how it workedHow does melanin determine human eye color?
• the bigger pictureWhat are colloids and particulate matter?
• whoWho was John Tyndall?
• what caused itWhat genes control human eye color inheritance?
• an unexpected connectionHow does early climate science connect to John Tyndall?Eunice Newton Foote discovered that carbon dioxide absorbs heat from sunlight years before John Tyndall published his work on the greenhouse effect.

Sources

• [1]Tyndall effect (Wikidata Q244040) · CC0 1.0
• [2]Tyndall effect · CC BY-SA 4.0
• [3]Blue · CC BY-SA 4.0
• [4]Eye color · CC BY-SA 4.0
• [5]Eunice Newton Foote · CC BY-SA 4.0

Your path

1. What determines human eye color?
2. /Why do blue eyes happen because of the Tyndall effect?