Amber eyes are a rare and unique eye color that can sometimes appear to shift between brown, gold, hazel, and greenish shades in different lighting conditions. This has led to questions around whether true amber eyes can also contain traces of green pigment. While amber eyes get their distinctive honey-golden hue primarily from a high concentration of melanin in the iris, there is some evidence that green hues can also be present in this eye color.
The Genetics Behind Amber Eyes
Amber eyes are the result of a genetic phenomenon known as ocular albinism, which causes the iris to produce a high level of melanin. Melanin is the pigment responsible for creating eye, skin, and hair color. Most people have a moderate to low concentration of melanin in their irises, allowing blue and green hues to show through more strongly. However, those with amber eyes have a higher concentration of melanin that overpowers other colors.
While scientists used to think that amber eyes contained only the brown/gold pigment eumelanin, more recent research indicates that in rare cases, the green pigment pheomelanin may also be present along with very high levels of eumelanin. This combination can result in eyes that shift between golden-brown to light greenish-yellow shades in different lighting.
Natural Variations in Amber Eyes
No two pairs of amber eyes are exactly alike. Even among those whose irises contain only the melanin pigment eumelanin, there can be variation in the precise ratio of eumelanin to other pigments. This results in amber eyes ranging from dark copper to bright honey-gold.
Some amber eyes may take on slightly different hues in the middle versus the outer part of the iris. And as mentioned, a small percentage of amber eyes may also contain traces of the green pigment pheomelanin mixed in with very high concentrations of eumelanin. This can lend a subtle greenish cast to the eyes in certain lighting.
| Amber Eye Variant | Genetic Profile |
|---|---|
| Dark Copper | Very high eumelanin, low pheomelanin |
| Golden | High eumelanin, very low pheomelanin |
| Honey | Moderately high eumelanin, trace pheomelanin |
| Greenish-Yellow | High eumelanin, moderate pheomelanin |
This table summarizes the typical genetic profile behind different shades of amber eyes. As it shows, greenish-yellow amber eyes have the highest levels of pheomelanin compared to other amber eye variants.
Lighting Effects on Amber Eyes
The lighting conditions present can also affect the way amber eyes appear. This is because different types of light bring out different undertones in the iris:
| Lighting | Effect on Amber Eyes |
|---|---|
| Natural Sunlight | Brings out warm golden, coppery tones |
| Indoor (incandescent) | Deepens to golden-brown or reddish hue |
| Fluorescent | Can lend a pale, yellowish-green tint |
| Flash Photography | May appear pale green, yellow, gray |
As demonstrated in the table, fluorescent and flash photography lighting often make amber eyes take on their subtle greenish aspects. This is due to the cool undertones these light sources produce.
Amber Eyes with Central Heterochromia
Some people with amber eyes have a condition called central heterochromia, where the center part of the iris is a different color than the outer part. In those with amber eyes, this can result in an amber, brown, or gold limbal ring around the pupil, with more greenish-yellow hues in the rest of the iris. The presence of the additional color in the central zone adds to the mosaic or multi-tonal appearance of these amber eyes.
Why Green Is Rare in Amber Eyes
While shades of green can be present in amber eyes, it tends to be relatively uncommon. This is because having high concentrations of both the melanin pigment eumelanin and the pheomelanin pigment at the same time is genetically rare. Most people have eyes that are predominantly influenced by either melanin (brown/amber eyes) or by pheomelanin (green/hazel eyes) but not both to a significant degree.
For green hues to visibly manifest in amber eyes likely requires a precise combination of:
– Very high eumelanin levels
– More than just trace pheomelanin levels
– Specific distribution of melanin across iris zones
– Lighting conditions that bring out pheomelanin undertones
This unusual convergence of genetics and environmental factors gives true greenish amber eyes their distinctive mystique and rarity.
Amber Eyes with Rayed Patterns
In addition to central heterochromia, some amber eyes exhibit other striking patterns in the iris such as:
– Rays/Spokes: Thin lines radiating out from the pupil
– Brushfield spots: Small white/grey dots on the iris
– Flecks: Tiny concentrations of color other than amber
These features can make amber eyes appear more dynamic. Green flecks or patches may be present alongside brown, gold, orange, or grey flecks. The rays can also help refract light in a way that brings out traces of green in some lighting.
Comparison to Hazel Eyes
Amber eyes are often confused with hazel eyes. However, while hazel eyes tend to be a blend of brown and green, true amber eyes have little to no identifiable green, and instead range from copper to bright yellowish-gold.
Hazel eyes are also quite common, while amber eyes are considered very rare globally. To summarize:
| Amber Eyes | Hazel Eyes | |
|---|---|---|
| Genetics | High melanin | Mix of melanin + pheomelanin |
| Rarity | Very rare | Common |
| Green Hues? | Minimal, if any | Clearly visible |
So while hazel eyes are defined by their dual brown-green coloration, true amber eyes exhibit little identifiable green.
Amber Eyes in Animals
Amber eye coloration is not limited only to humans. Various animal species also commonly display yellow, copper, and golden eye shades:
– Wolves
– Coyotes
– Eagles
– Owls
– Bears
– Cougars
– Cattle
– Dogs
– Cats
– Snakes
– Fish
The amber color generally serves a similar purpose in animals as in humans, resulting from a high concentration of melanin pigments in the iris. This helps restrict light from entering the eye in bright environments. As a result, amber eye color is especially common in predatory creatures and those that are routinely active in daylight.
Conclusion
While pure amber eyes do derive their golden-brown hue mainly from melanin pigments, some rare individuals may exhibit hints of green in their iris as well. This greenish tint likely comes from a mix of high melanin with moderate levels of the pheomelanin pigment. The exact combination and distribution of these pigments, plus lighting conditions, create the subtle greenish sheen sometimes seen in amber eyes. However, true green hues tend to be relatively uncommon and minimal in eyes that are predominantly amber in color.
