They fall into the amber, hazel, green, grey, and blue range. This results in “chameleon eyes”, or eyes that change color. In other words, the same scattering of light that occurs in the sky takes place in miniature within the outer layer of the iris.īecause of this, changes in the light being scattered by the iris of lighter colored eyes will change the apparent color of the eyes. Instead, they have a light brown pigmentation mixed with a blue optical effect caused by Rayleigh scattering. Is it possible there will be more green eyed people in the future due to globalisation? For now only time will tell.Īs mentioned before, green eyes actually have no green pigmentation. Several passes through the mountain range made it a strategic region or military and trade(silk road). Notably, there have been records of people with green eyes originating around the Caucasus mountains, which links Europe and Asia. Green eyes most likely developed because of the migration of people over time, those from northern latitudes with light coloring traveling south and people of dark coloring traveling north intermixed leading to a variation of melanin produced. All races, including white, black, Asian, and indigenous peoples of the Americas can also have green eyes. Northern Africa and countries such as Iran, Pakistan, Afghanistan, Central Asia, Spain, and Brazil all have had people with green eyes for a long time. This means that there is a chance that a newborn child can inherit virtually any eye color, no matter the eye color of the parents (although the chances for people of certain heritages are different than for others). Now it is proven that eye color is controlled by more than one gene in fact, up to 16 genes contribute to eye color. The study disproving this Mendelian theory for eye color was published in the American Journal of Human Genetics, and was supported with grants from Australia’s National Health and Medical Research Council and the United States of America’s National Cancer Institute. And only a combination of two blue genes would express itself as green. A green gene and a blue gene would express itself as blue. A brown gene and a blue or green gene would express itself as brown. Therefore two brown genes would obviously express itself as brown. You received two genes for an eye color, one gene from each parent, and whichever was the dominant gene would express itself. Brown was dominant over green, which was dominant over blue. Until 2007, it was believed that there was a hierarchy of eye color. Only 2% of the world’s population have green eyes or 140 million people.