Hazel eyes are dominant

Eye colors - a fascinating look into the soul?

This is how the different eye colors are created

The question of the origin of human eye colors is closely related to another question: Why are there actually different eye colors in the human eye? This is pretty unique in the animal world. There are wild animals whose eye color can adapt to external conditions, for example for camouflage or for better vision when hunting, but the fact that the basic color of the eyes is different in one species only occurs in a few farm animals and does not occur in the wild at all .

In fact, people also had a long time ago just one eye color- namely brown - until a gene mutation occurred. Researchers estimate that the first person with blue eyes was around eight to ten thousand years ago. The mutation concerned the gene which determines the amount of melanin pigments and thus indirectly not only determines the color of the eyes, but also the color of the skin and hair.

Melanins are brownish color pigments that are mostly only formed in the pigment layer of the iris after birth. The more melanin there is, the darker the eye color becomes. The melanin concentration is lowest in blue eyes and highest in brown eyes. Genetic predisposition determines the amount of color pigments. Changes in the body's hormonal balance can cause the pigment density on the iris to change, but this only causes a slight change in the shade of color. It is not possible to change the basic color.

Eye colors and their inheritance

When asked "What are the colors of the eyes?" The answer is usually: brown, blue, green and gray. Of course, this is just a schematic simplification. In many cases they are several colors in different proportions available. This is due to the fact that the pigment layer of the iris is not completely even. In some places, more melanin is formed than in others, causing blue-gray, gray-green or even blue-gray-green eyes, to name just a few.

That also plays a role when it comes to eye color and its inheritance. Strictly speaking, it is not the color, but rather the genetic information about the strength of the pigmentation is passed on. How exactly this works has not yet been fully deciphered. The following findings are considered scientifically proven:

  • Not just one gene, but several determine the color, expression and shades of the iris.
  • With different genes, the dominant expression determines which eye color is passed on through inheritance.
  • The order of dominance is: brown, green, blue, gray.
  • The gene variants (alleles) that are decisive for eye color have little influence on hair and skin color; only the alleles for blue eyes and red hair cause lighter skin color.

 

By the way, how dominant an eye color is in inheritance does not necessarily depend on its distribution. Around 90 percent of all people have brown eyes, regardless of their skin color. However, green eyes are the rarest. They occur in less than 2 percent of people.

Does the color of the eyes matter?

Until the invention of colored contact lenses, the eyes were considered to be one of the few physical characteristics that could not be changed. For this reason, they have always been given special importance in “deciphering” a person. In the past, it was a common practice to infer character from eye color.

The Scientists are still concerned with the connection between eye color and character, but there is hardly any solid evidence. So far, researchers at Örebro University in Sweden have come the furthest. They found that one of the genes that determine the appearance of the iris also affects the areas of the brain for emotion and behavior.

However, many studies have shown that Eye colors associated with certain character traits become. These connections date from times long past and have been passed on from one generation to the next over centuries through stories, proverbs and similar traditions.

Against this background, one can definitely ask: What does the eye color say?

People with blue eyes are considered cool, reserved, reserved, courageous, humble and strong-willed. Much importance has been "attributed" to blue eyes, especially in literature. Depending on the culture, they were chosen as a characteristic of strong, courageous fighters or demonic, cold-blooded villains.

But there are also some solid facts about blue eyes:

    • Almost all babies of Central European descent are born with blue eyes. The formation of melanin does not begin until the first year of life. So it can happen that the final eye color only shows in advanced toddler age.
    • With blue eyes there is an increased risk of developing eye diseases such as eye cancer or age-related macular degeneration (AMD), which are triggered or promoted by dangerous UV radiation.

 

People with green eyes are mostly described as mysterious, seductive, jealous, adventurous, intelligent and unpredictable. One of the most famous and at the same time cruelest examples of an arbitrary connection between eye color and character is that Witch hunt, in which green eyes were of particular importance. They were considered a sign of magical disposition and admiration for the devil, due to which all green-eyed women were put under general suspicion.

People with brown eyes are rated as trustworthy, loyal, caring, strong and optimistic. "Hazel Eyes" receive special attention - a phenomenon that the German translation "hazelnut brown eyes" does not adequately describe. It means that the iris contains green, brown and blue components in such a balanced way that the eye color appears different depending on the incidence of light.