Dark brown eyes that appear almost black are often considered one of the rarest eye colors in the world. But are they really as uncommon as people think? Let’s take a closer look at the genetics, statistics, and fascinating facts around this eye color.
What Causes Dark Brown/Black Eyes?
Eye color is determined by the amount of a pigment called melanin in the iris of the eye. The more melanin present, the darker the eye color.
Here’s a quick breakdown of how melanin affects eye color:
- Low melanin = blue/green eyes
- Medium melanin = green/light brown eyes
- High melanin = dark brown/black eyes
Dark brown eyes have a very high concentration of melanin in the iris, which makes them appear almost black or very dark brown.
The Genetics Behind Dark Brown Eyes
The main gene that controls eye color is called the OCA2 gene. Within this gene there is a specific variation that largely determines whether someone will have brown/black eyes versus lighter colored eyes like blue and green.
This brown/blue variation acts in a nearly dominant way. This means that even just one copy of the brown version of the gene will make someone likely to have brown eyes.
To have super dark brown/black eyes, both copies of a person’s OCA2 genes must contain the variant for brown. This makes their eye color very dark, compared to people who only have one brown variant and one blue.
Global Statistics on Black/Brown Eyes
When looking at global statistics, dark brown or black eyes are actually quite common around the world. Here are some estimates on the prevalence of this eye color:
- About 45% of the world’s population has brown eyes
- Dark brown eyes make up around 15-25% of the global population
- Black/brown eyes are the most common eye color worldwide
Regionally, those with very dark brown or black eyes make up the majority of people in parts of Africa, East Asia, South Asia, Southeast Asia, Latin America, and the Middle East.
In contrast, lighter eye colors like blue and green are rarer globally but are more common in certain areas of Europe, West Asia, and North America.
Eye Color Frequencies by Region
| Region | Blue/Green Eyes | Light Brown Eyes | Dark Brown/Black Eyes |
|---|---|---|---|
| Europe | 29% | 42% | 29% |
| Africa | 5% | 15% | 80% |
| East Asia | Less than 1% | 25% | More than 70% |
This data shows that when looking globally, dark brown or black eyes are actually the most common by a significant margin over lighter eye colors.
Are Dark Eyes Rare in Certain Populations?
While dark brown/black eyes are quite common worldwide, they are less prevalent in certain ethnic groups and populations.
For example, these eye colors are relatively uncommon among Caucasian populations in Europe and North America. One study of eye color in white Americans found the following frequencies:
- Blue eyes – 33%
- Green eyes – 9%
- Light brown eyes – 28%
- Dark brown eyes – 21%
Compared to the global frequencies, blue, green, and light brown eyes are significantly more common in white Americans. Only around 21% were found to have very dark brown irises.
In contrast, over 75-90% of native populations from parts of Africa, Asia, and Latin America have dark brown or black colored eyes.
Populations With Low Rates of Dark Eyes
| Population | Rate of Dark Brown/Black Eyes |
|---|---|
| British Caucasians | 10-25% |
| White Americans | Around 21% |
| Northern Europeans | 10-30% |
Within these populations, dark brown eyes are uncommon compared to other parts of the world. But Globally they remain the most frequent eye color.
What Makes Dark Eyes Appear Black?
When someone’s eyes appear to be fully black or nearly black, it is the result of having a very high amount of melanin pigment in the iris.
However, in certain lighting conditions even very dark brown eyes may show some color around the pupil. Here are some factors that can make dark eyes appear blackish:
- Low light conditions – low brightness makes it hard to discern color
- Overcast weather – clouds scatter sunlight and reduce intensity
- Small pupil size – the iris appears darker when contracted
- Viewer distance – harder to see color variations from afar
- Lack of reflectivity – some irises absorb more light
Because of these factors, many people with very dark brown eyes often report their eyes looking black. But on closer inspection or in bright light some reddish-brown hues might be visible in the iris.
True Black Eyes
While extremely rare, some people can have true black pigmentation in the iris from melanosis or increased melanin deposits. This can make the eyes look fully black without any hints of brown.
Having complete black eyes unrelated to factors like lighting is very uncommon. Even most eyes that look blackish have some brown hues that are visible on close examination.
Interesting Facts About Dark Brown/Black Eyes
Beyond the genetics, here are some fascinating facts about nearly black eye color:
- Darker eyes offer more protection from UV damage and sunlight.
- Brown/black eyes are thought to have developed originally as an evolutionary adaptation in sunny climates near the equator.
- People with very dark eyes are often considered to have a more mysterious appearance.
- Brown/black eyes tend to have less variation in shade than lighter colors that have more freckling and patterns.
- Dark eyes are associated with increased production of melanin overall in the body, such as darker hair and skin.
Celebrities with Dark Brown/Black Eyes
Many celebrities naturally have very dark brown eyes that can appear black. Some examples include:
- Johnny Depp
- Angelina Jolie
- Bruno Mars
- Keanu Reeves
- Kim Kardashian
- Taylor Lautner
Conclusion
While dark brown eyes may appear rare and exotic in some parts of the world, globally they are the most frequent eye color by a large margin. However, brown/black eyes are relatively uncommon in populations with greater genetic influence from Northern Europe and Western Asia.
The appearance of blackish eyes comes from very high concentrations of the melanin pigment in the iris. But even most seemingly black eyes show hints of brown on close inspection in good lighting.
So in summary – dark brown/black eyes are not uncommon worldwide. But they are rare in certain ethnic groups while being quite common in others. Their mysterious and alluring appearance will likely continue to fascinate those who possess these beautiful dark eyes!
