Just as it takes many strokes of the artist's brush to produce a masterpiece, hazel eyes involve the dynamics of several elements to create the unique work of art that's represented in every hazel eye. Hazel eye colour is both complex and magnificent, since its specific features are determined by many factors - including the amount and distribution of melanin in the iris, how scattering of light by the iris and pigment molecules affects colour, and how perception of eye colour is influenced by lighting and the colour of our clothing and surroundings. Scatter more easily than light rays with longer wavelengths (red light), eyes with less light-absorbing melanin appear green or hazel, and eyes with low concentrations of melanin appear blue.Īlso, the distribution of melanin can vary in different parts of the iris, causing hazel eyes to appear light brown near the pupil and more green in the periphery of the iris. Since light rays with shorter wavelengths (blue and green light) In eyes with lower concentrations of melanin, less light is absorbed, and more is scattered and reflected by the iris. Light is scattered and reflected by the iris, and some wavelengths (colours) scatter more easily than others.Įyes with high concentrations of melanin absorb more light entering the eye, so less is scattered and reflected back from the iris. Melanin in the iris absorbs different wavelengths of light entering the eye. So how can a dark brown pigment create blue, green or hazel eyes? This is possible because of two processes: Eyes merely have different amounts of melanin, which is a dark brown pigment. There are no blue, green or hazel pigments in the eye. This is because these individuals naturally have more melanin in their eyes and skin, compared with non-Hispanic whites. Those who end up with green eyes or hazel eyes develop a little less.īabies of African American, Hispanic and Asian ethnicities usually are born with dark eyes that stay brown throughout life. In the first few years of life, more melanin may accumulate in the iris, causing blue eyes to turn green, hazel or brown.īabies whose eyes turn from blue to brown develop significant amounts of melanin. The reason many white, non-Hispanic babies are born with blue eyes is that they don't have the full amount of melanin present in their irises at birth. The pigment responsible for eye colour is called melanin, which also affects skin colour. The pigmented structure inside the eye that surrounds the pupil and gives eyes their colour is called the iris. This phenomenon has little to do with genetics, but it does help explain where hazel eyes come from. Many white, non-Hispanic babies are born with blue eyes and then develop brown, green or hazel eyes in childhood. For example, we now know it's possible for two blue-eyed parents to have a child with brownĮyes - something the old model of eye colour inheritance would have deemed impossible.Īlso, eye colour can change dramatically in the first few years of life. Recent research has shown that up to 16 genes (not just one or two) may influence eye colour, which makes predicting eye colour much more difficult.ĭue to variations in the interaction and expression of multiple genes, it's hard to say for sure what colour a child's eyes will be based on the colour of his or her parents' eyes. So two parents with blue eyes cannot have a child with brown eyes because neither parent carries the dominant form of the gene for brown eyes.īut it turns out the story is more complicated than that. Most of us were taught in high school science class that we inherit our eye colour from our parents, and that brown eye colour is dominant and blue is recessive. So where does this stunning colour come from? What determines eye colour? One of the reasons it's so hard to describe hazel-coloured eyes is that the hue itself seems to change, depending on what you wear and the type of lighting you are in.Īlso, although hazel eyes appear to contain hues of green, amber and even blue, these colour pigments don't exist in the human eye. Some say it looks like hazelnut, while others call it golden or brownish green. For starters, people describe this beautiful eye colour in many different ways.
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