What causes difference in the coloration of your eye pupil?

The coloration of your eye pupil is primarily determined by the amount and distribution of melanin, a pigment, in the eye's iris. Melanin is responsible for giving color to the skin, hair, and eyes. People with more melanin in their irises tend to have darker-colored eyes, such as brown or black, while those with less melanin have lighter-colored eyes, such as blue or green.

Other factors can also influence the coloration of the eye pupil, including:

1. Genetics: The genes you inherit from your parents play a significant role in determining your eye color. Certain genes control the production of melanin and its distribution within the iris.

2. Age: The amount of melanin in the iris can change over time. For instance, some babies are born with light-colored eyes, and their eye color darkens as they grow older due to increased melanin production.

3. Light conditions: The lighting conditions in which you view your eyes can affect their apparent color. For example, your eyes may appear darker in bright sunlight due to the increased dilation of the pupil, which allows more light to enter and activate the melanin-producing cells.

4. Medical conditions: Certain medical conditions, such as albinism, can affect the production and distribution of melanin, resulting in reduced eye coloration.

It is worth noting that the coloration of the eye pupil can vary within the same individual under different circumstances, such as changes in lighting conditions, emotions, or certain physiological responses like dilation and constriction of the pupil.