Colored Eyes
Eye color or eye colour is a polygenic phenotypic character determined by two distinct factors: the pigmentation of the eye's iris and the frequency-dependence of the scattering of light by the turbid medium in the stroma of the iris. Iris color can provide a large amount of information about a person, and a classification of colors may be useful in documenting pathological changes or determining how a person may respond to ocular pharmaceuticals. Classification systems have ranged from a basic light or dark description to detailed gradings employing photographic standards for comparison. Others have attempted to set objective standards of color comparison.
We often see some people who have really great eyes and wish we could have eyes like them but one must always remember that the very fact that you have an eyesight is a great gift of nature and we must be ever-so-grateful about it. The various scintillating colors of a person’s eyes often attracts us towards them.
Eyes can tell a lot about a person: what they’re thinking and feeling, of course, and whether they’re lying or loyal. This is perhaps why the adage “the eyes are the window to the soul” rings true. But though your eye color may seem rather superficial, it can say a lot about your health too, in ways you may not have been aware.
1. Black Eyes
One of the most surprising things about the black colored pair of eyes is that true black eyes are very rare. What we see and call as black eyes are in actuality just very dark brown eyes. The dark brown or black, as we may call it for own usage is often associated with night, mystery and intuition. People with black eyes are said to be very trustworthy and responsible. They are secretive but will never let your secrets out to anyone. They sometimes mistrust people and are reluctant to start friendships and to fall in love. But when they do begin a relation, they are loyal till the very end. They are extremely hardworking and practical and will always give their best shot at whatever it is that they are doing. They are said to be spiritual, passionate and optimists. They always know how to show their worth to others.
2. Brown Eyes
The most common eye color in the world is brown. When we say brown, we talk about light to medium brown and not very dark brown. People with brown eyes are attractive and confident. It is a strong and rich color and it is associated with earth and thus, things like simplicity, creativity and positivism are some things that you can always find in people who have such brown eyes. They are independent, polite, caring and love making new friends and they are always up for trying new things in life. They are also practical but when it comes to the people they care about, practicality tends to take a back-seat as love and care overtakes it. They are usually the happy-go-lucky people who don’t care much for earthly possessions and are close to all things nature. Even though they are self-confident and determined, sometimes, they can have a hard time trying to express themselves to people. Great lovers and mighty trust-worthy, these people are the ones who you can go to for any help and they will go out of their way to make sure you are happy and satisfied.
In humans, brown eyes result from a relatively high concentration of melanin in the stroma of the iris, which causes light of both shorter and longer wavelengths to be absorbed.
Dark brown eyes are dominant in humans and in many parts of the world, it is nearly the only iris color present. Dark pigment of brown eyes is common in East Asia, Southeast Asia, Central Asia, South Asia, West Asia, Oceania, Africa, Americas, etc. as well as parts of Eastern Europe and Southern Europe. The majority of people in the world overall have dark brown eyes. Dark brown is often found in the Semitic people, among Jewish and Arab populations in the Middle East.
Light or medium-pigmented brown eyes can also be commonly found in South Europe, among the Americas, and parts of Asia(Middle East and South Asia). Light-pigmented brown eyes are sometimes referred to as "honey eyes".
3. Hazel Eyes
Hazel is a beautiful mixture of brown and green and this eye color looks breath-takingly good. Elegant is the first word that is associated with people with hazel eyes. They are very spontaneous, fun-loving and always up for an adventure at point of time. Going with the flow and adapting easily to any situation is definitely their forte. They are brave and courageous people who encourage diversity and they tend to get bored of monotony very easily. They love to try new things. Their beauty often attracts many people to people with hazel eyes but the relationships of hazel eyed person may not last very long unless you are THE ONE for them. Mischievous and sensual in equal measure, they make for great personalities. One thing that you need to be aware of is their temper. If you can handle that, then you are in for a joy-ride.
Hazel eyes are due to a combination of Rayleigh scattering and a moderate amount of melanin in the iris' anterior border layer. Hazel eyes often appear to shift in color from a brown to a green. Although hazel mostly consists of brown and green, the dominant color in the eye can either be brown/gold or green. This is how many people mistake hazel eyes to be amber and vice versa. This can sometimes produce a multicolored iris, i.e., an eye that is light brown/amber near the pupil and charcoal or dark green on the outer part of the iris (or vice versa) when observed in sunlight.
Definitions of the eye color hazel vary: it is sometimes considered to be synonymous with light brown or gold, as in the color of a hazelnut shell.
Hazel eyes are common throughout Caucasoid populations, in particular in regions where blue, green and brown eyed peoples are intermixed.
4. Grey Eyes
Grey is a color that dominated a lo in our life. As they say, life is not just black and white but just different shades of grey. Similarly, people with grey eyes and born to be dominant and leaders. Strong in nature, wise and gentle are some of the most important attributes that they possess. One must know that they are very gentle. In fact, people with grey eyes are the least aggressive people of all. They put all their passion in whatever they do, be it profession or personal. They take love and romance very seriously and these are not the kind of people whom you will see fooling around. They are creative and imaginative, and flexible in their attitude – the 3 qualities that every great leader possesses. Their inner strength, analytic thinking and rationality given them an upper hand in taking a leading rose in any situation. These are great people to be around and their company will surely have a posiive effect on you as well.
Like blue eyes, gray eyes have a dark epithelium at the back of the iris and a relatively clear stroma at the front. One possible explanation for the difference in the appearance of gray and blue eyes is that gray eyes have larger deposits of collagen in the stroma, so that the light that is reflected from the epithelium undergoes Mie scattering (which is not strongly frequency-dependent) rather than Rayleigh scattering (in which shorter wavelengths of light are scattered more). This would be analogous to the change in the color of the sky, from the blue given by the Rayleigh scattering of sunlight by small gas molecules when the sky is clear, to the gray caused by Mie scattering of large water droplets when the sky is cloudy. Alternatively, it has been suggested that gray and blue eyes might differ in the concentration of melanin at the front of the stroma.
Gray eyes are most common in Northern and Eastern Europe. Gray eyes can also be found among the Algerian Shawia people] of the Aurès Mountains in North West Africa, in the Middle East, Central Asia, and South Asia. Under magnification, gray eyes exhibit small amounts of yellow and brown color in the iris.
5. Green Eyes
Green and greenery is always a breath of fresh air and rejuvenation. So obviously, people with green eyes are like a gust of strong and fresh winds. They always have a room of mystery and enigma around them and a look into someone’s green eyes can make you get lost in them within seconds. Intelligent and always curious, green eyed people are always the first to take interest in something new. They have an incredible zeal and zest for life and for living live to the fullest. They are passionate about many things. And of course, with an eye color so enchanting, they tend to be very attractive and beautiful as well. The only negative factor is that they get jealous very soon. But overall, the positives defeat the negative. Youthfulness oozes out of them and the compassion and vibrancy that they bring along wherever they go is contagious.
As in the case of blue eyes, the color of green eyes does not result simply from the pigmentation of the iris. Rather, its appearance is caused by the combination of an amber or light brown pigmentation of the stroma, given by a low or moderate concentration of melanin, with the blue tone imparted by the Rayleigh scattering of the reflected light.
Green eyes probably result from the interaction of multiple variants within the OCA2 and other genes. They were present in south Siberia during the Bronze Age.
They are most common in Northern and Central Europe. They can also be found in Southern Europe and Western Asia (especially among Ashkenazi Jews of Israel). In Ireland and Scotland 14% of people have brown eyes and 86% have either blue or green eyes,In Iceland, 89% of women and 87% of men have either blue or green eye color.A study of Icelandic and Dutch adults found green eyes to be much more prevalent in women than in men. Among European Americans, green eyes are most common among those of recent Celtic and Germanic ancestry, about 16%. Green eyes are common in Tabby cats as well as the Chinchilla Longhair and its shorthaired equivalents are notable for their black-rimmed sea-green eyes.
6. Blue Eyes
"Blue eyes" redirects here. For other uses, see Blue eyes (disambiguation).
There is no blue pigmentation either in the iris or in the ocular fluid. Dissection reveals that the iris pigment epithelium is brownish black due to the presence of melanin. Unlike brown eyes, blue eyes have low concentrations of melanin in the stroma of the iris, which lies in front of the dark epithelium. Longer wavelengths of light tend to be absorbed by the dark underlying epithelium, while shorter wavelengths are reflected and undergo Rayleigh scattering in the turbid medium of the stroma. This is the same frequency-dependence of scattering that accounts for the blue appearance of the sky.The result is a "Tyndall blue" structural color that varies with external lighting conditions.
In humans, the inheritance pattern followed by blue eyes is considered similar to that of a recessive trait (in general, eye color inheritance is considered a polygenic trait, meaning that it is controlled by the interactions of several genes, not just one). In 2008, new research tracked down a single genetic mutation that leads to blue eyes. "Originally, we all had brown eyes," said Eiberg.
Eiberg and colleagues suggested in a study published in Human Genetics that a mutation in the 86th intron of the HERC2 gene, which is hypothesized to interact with the OCA2 gene promoter, reduced expression of OCA2 with subsequent reduction in melanin production.The authors suggest that the mutation may have arisen in the northwestern part of the Black Sea region, but add that it is "difficult to calculate the age of the mutation."Eiberg stated, "A genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a 'switch,' which literally 'turned off' the ability to produce brown eyes." He added:
Blue eyes are common in northern and eastern Europe, particularly around the Baltic Sea. Blue eyes are also found in Southern Europe and Western Asia, especially among the Jewish population of Israel. Many modern Israeli Jews are of European Ashkenazi origin, among whom this trait is common (a study taken in 1911 found that 53.7% of Ukrainian Jews had blue eyes). In Ireland and Scotland 86% of people have either blue or green color eyes.
We leave the best for the last always, don’t we? There is something about the blue color that is so fresh and lively that people always desire this color and are instantly attracted towards it. No prizes for guessing that blue eyes are the most desired eye color in the world. Peaceful, smart, kind and full of youth and life, blue eyed people have long-lasting relationships and are very energetic. But the most prominent feature among them is their inherent desire to make other people happy. Blue eyed people will go the extra mile just to make sure that you are happy with utmost kindness and sincerity. This one feature is very rare and that is what makes the blue-eyed person so appealing to us. They are very keen on observing things, are extroverts and always happy-go-lucky. A person with blue eyes wants a long-lasting and a full-commitment and a no-bullshit relationship. Once they have that, they will do everything under the sun to make their better-halves happy. We all want a blue-eyed person in our lives, do we not? Well :)
7. Amber Eyes
Amber eyes are of a solid color and have a strong yellowish/golden and russet/coppery tint. This may be due to the deposition of the yellow pigment called lipochrome in the iris (which is also found in green eyes). Amber eyes should not be confused with hazel eyes; although hazel eyes may contain specks of amber or gold, they usually tend to comprise many other colors, including green, brown and orange. Also, hazel eyes may appear to shift in color and consist of flecks and ripples, while amber eyes are of a solid gold hue. Even though amber is considered to be like gold, some people have russet or copper colored amber eyes that many people mistake for hazel, though hazel tends to be duller and contains green with red/gold flecks, as mentioned above. Amber eyes may also contain amounts of very light gold-ish gray.
The eyes of some pigeons contain yellow fluorescing pigments known as pteridines. The bright yellow eyes of the great horned owl are thought to be due to the presence of the pteridine pigment xanthopterin within certain chromatophores (called xanthophores) located in the iris stroma.[In humans, yellowish specks or patches are thought to be due to the pigment lipofuscin, also known as lipochrome.Many animals such as canines, domestic cats, owls, eagles, pigeons and fish have amber eyes as a common color, whereas in humans this color occurs less frequently.
Considered stunning and hypnotizing, the amber eye is, as with all eye colors, an inherited trait and involves many complex DNA genes and other various gene stems.
These genes can be tracked by noting any changes or associations with neighboring genes.
When these changes occur it creates what is called a single-nucleotide polymorphism or (SNP.) During a study conducted at Rotterdam in (2009) it was discovered that the prediction of eye color could be done using only six out of sixteen SNPs.
However, this specification could not account for the many variations that occur with brown, blue and hazel eye colors, including amber. So the exact coming together of the genes and genomes responsible for causing amber eye color still has not been isolated and identified. Amazing Amber!
8. Heterochromia
Heterochromia (also known as a heterochromia iridis or heterochromia iridum) is an ocular condition in which one iris is a different color from the other iris (complete heterochromia), or where a part of one iris is a different color from the remainder (partial heterochromia or sectoral heterochromia). It is a result of the relative excess or lack of pigment within an iris or part of an iris, which may be inherited or acquired by disease or injury. This uncommon condition usually results due to uneven melanin content. A number of causes are responsible, including genetic, such as chimerism, Horner's syndrome and Waardenburg syndrome.
A chimera can have two different colored eyes just like any two siblings can—because each cell has different eye color genes. A mosaic can have two different colored eyes if the DNA difference happens to be in an eye-color gene.
There are many other possible reasons for having two different-colored eyes. For example, the film actor Lee Van Cleef was born with one blue eye and one green eye, a trait that reportedly was common in his family, suggesting that it was a genetic trait. This anomaly, which film producers thought would be disturbing to film audiences, was "corrected" by having Van Cleef wear brown contact lenses.David Bowie, on the other hand, had the appearance of different eye colors due to an injury that caused one pupil to be permanently dilated.
Another hypothesis about heterochromia is that it can result from a viral infection in utero affecting the development of one eye, possibly through some sort of genetic mutation. Occasionally, heterochromia can be a sign of a serious medical condition.
A common cause in females with heterochromia is X-inactivation, which can result in a number of heterochromatic traits, such as calico cats. Trauma and certain medications, such as some prostaglandin analogues, can also cause increased pigmentation in one eye.On occasion, a difference in eye color is caused by blood staining the iris after injury.
9. Red and violet
The eyes of people with severe forms of albinism may appear red under certain lighting conditions owing to the extremely low quantities ofmelanin, allowing the blood vessels to show through. In addition, flash photography can sometimes cause a "red-eye effect", in which the very bright light from a flash reflects off the retina, which is abundantly vascular, causing the pupil to appear red in the photograph.Although the deep blue eyes of some people such as Elizabeth Taylor can appear violet at certain times, "true" violet-colored eyes occur only due to albinism
"Eyes are not only for seeing, but also to be seen,"
credits:
- wikipedia.org
- medicaldaily.com
- http://listovative.com/
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