Hazel eyes are defined as eyes that contain a mixture of brown and green. They can appear more green or brown depending on lighting conditions. Hazel eyes are quite rare globally, occurring in only about 5-8% of the population. When looking at which populations and ethnicities have the highest rates of hazel eyes, European ancestry tends to predominate.
Northern, Central, and Eastern European Ancestry
Those with Northern, Central, and Eastern European ancestry tend to have some of the highest rates of hazel eyes in the world. This includes countries like:
- Finland
- Estonia
- Latvia
- Lithuania
- Belarus
- Ukraine
- Czechia
- Slovakia
- Hungary
- Poland
- Russia
In these countries, hazel eyes can occur in anywhere from 10-20% of the native populations. For example, a study of schoolchildren in Estonia found hazel eyes in 13% of participants. In Russia, hazel eyes were found in 16% of the population according to self-reported data. These rates are significantly above the global average.
Scandinavian Ancestry
Those with Scandinavian ancestry also tend to have high rates of hazel eyes. This includes countries like:
- Sweden
- Norway
- Denmark
- Iceland
In Iceland, studies have found hazel eye color in up to 20% of natives. In Sweden and Norway, rates are slightly lower but still above average at around 10-15%. Scandinavian ancestry therefore accounts for some of the highest hazel eye rates globally.
British and Irish Ancestry
Individuals with British and Irish ancestry also commonly exhibit hazel eyes. Rates are highest in Ireland and Scotland, where up to 16% of the population has hazel eyes. In England and Wales, rates are closer to the average at 6-10%. But overall, British and Irish ancestry results in elevated hazel eye percentages compared to most other world populations.
Reasons for High Rates in Northern Europe
There are a few key reasons Northern European populations tend to have higher rates of hazel eyes:
- Greater genetic diversity – More combinations of eye color genes
- Evolutionary advantage – Hazel eyes performed better in Northern latitudes
- Founder effects – Small populations amplified certain traits
- Sexual selection – Hazel eyes considered attractive
The combination of these evolutionary and genetic factors resulted in hazel eyes becoming quite common among Northern Europeans. The trait was passed down through generations and concentrated in these populations.
Other World Populations with Hazel Eyes
While Northern Europeans have some of the highest documented rates of hazel eyes, the trait can occur globally. Other populations with above average hazel eye percentages include:
- Ashkenazi Jews – Up to 15%
- Middle East – 5-10% in some regions
- Central Asia – 5-7%
- North Africa – 4-6%
- North America – 5-8%
These populations exhibited intermixing with European groups throughout history, introducing the genes for hazel eyes. As a recessive trait, hazel eyes can occur even when population rates are low if both parents carry the genetic components.
Lowest Rates of Hazel Eyes Globally
In contrast to Northern Europeans, hazel eyes are extremely rare in certain world populations. The lowest documented rates of hazel eyes globally tend to occur in East Asian and Sub-Saharan African ancestry groups. For example:
- China – Less than 1%
- Japan – Less than 1%
- Korea – Less than 1%
- Nigeria – Less than 1%
- Ethiopia – Less than 1%
These populations have little to no European ancestral mixing. Hazel eyes are considered very uncommon. The only exceptions are cases of interracial children who may exhibit hazel eyes at somewhat higher rates.
Factors that Impact Hazel Eye Color
Several factors can impact the exact shade and appearance of hazel eyes:
Melanin Content
The amount of melanin pigment present affects hazel eye color. More melanin results in eyes appearing darker brown/green. Less melanin leads to a lighter golden/green appearance.
Rayleigh Scattering
This optical effect makes eyes appear more blue in the center and more golden/brown around the rim. It contributes to the multi-color nature of hazel eyes.
Lighting Conditions
Hazel eyes can look more green in natural sunlight and more brown in indoor lighting. The balance of melanin and Rayleigh scattering changes with different light.
Age
Hazel eyes often get darker with age as melanin levels increase. Young children with hazel eyes tend to have a lighter golden shade that progressively darkens.
| Age Group | Typical Hazel Eye Color |
|---|---|
| Newborn | Light gold/yellowish green |
| Child | Light to medium golden green |
| Teenager | Greenish light brown |
| Adult | Richer golden brown/green |
| Elderly | Darker greenish brown |
Conclusion
In summary, the populations with the highest percentages of hazel eyes globally are those of Northern, Central, and Eastern European ancestry. Countries like Finland, Estonia, Poland, and Russia have some of the world’s highest documented rates of hazel eyes, up to 20% in some regions. Scandinavian groups, as well as British and Irish populations, also exhibit elevated hazel eye levels compared to global averages. Hazel eyes were likely an evolutionary adaptation in Northern Europe and were concentrated in these populations. They can still occur through mixed ancestry worldwide but remain exceptionally rare in places like East Asia and Sub-Saharan Africa that lack European mixing. The exact shade of hazel eyes is variable based on melanin content, lighting, optics, and age. But the overall prevalence is clearly highest in those with recent Northern European heritage.