What? Did you read that right? Yes. There are no blue or green colors, all of us actually have brown eyes.
What makes the color in our eyes exactly? The melanin of the iris, which is actually “a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupil and thus the amount of light reaching the retina”.
Approximately 18% of the USA population has light color of the iris, but this doesn’t mean they have green or blue eyes. Science has proven that it is actually a shade of brown.
This is due to the level presence of melanin in the iris. The melanin is responsible for the pigmentation of the skin and the hair as well, also, the iris.
This is also the reason why most of the babies are born with light eyes and over time, they become darker and brown. It is all because the melanin hasn’t yet developed in the fragile baby and the melanocytes react with the light of the surrounding.
That’s why people from the Northern countries, like Finland, Sweden, Russia, seem to have lighter eyes. Because of the lack of strong sun light.
So, some eyes seem blue or green simply because of the lack of melanocytes. This process is called “Tyndall scattering” and it is actually the way the light waves scatter across the reflective surface of the eyes.
Hazel or brown eyes have an average medium amount of melanocytes, resulting to the mixture of brown, green and yellow color in the iris who mix up under different sunlight.
The most common color of eyes on the planet, now and 8000 years ago is medium to dark brown. Though your eyes might be brown, they certainly don’t look like that all the time. Depending the sun, the color of the clothes or make up you’re wearing, the presence of the sea or ocean etc.
At the end, here’s an interesting theory that explains why some people have lighter color of the eyes than others. Back in the days, when our ancestors migrated to cooler parts of the Earth, they didn’t need as much melanin in their eyes, because the lack of sunlight in those areas.
But, the inheritance of the color of your eyes is a polygenic trait – this means that not only a straight line leading to your ancestors is your inheritance, but many multiple genes are involved.
The study shows that “ melanin in someone’s eye, implying that eye color traits do not follow the traditional rules of inheritance”. The color of the eyes also might skip a generation, so your precious baby inherits older gene factors when it comes to this. With the eye color, you just can’t ever be sure about.Sources: https://edition.cnn.com/ https://link.springer.com/ https://www.littlethings.com/ https://www.nature.com/