Does eye colour in humans usually have a genetic cause, an environmental cause or both?bothgeneticenvironmental

Eye colour in humans is primarily determined by genetics. The colour of our eyes is decided by the amount and type of pigments in the eye's iris, the density of cells in the iris, and how these cells are arranged. This is all controlled by multiple genes that we inherit from our parents.

However, the environment can also have a minor influence. For example, the eye colour can appear to change or enhance due to lighting conditions, clothing, and makeup. But these are not actual changes in eye colour, but rather perceptions of colour changes.

So, while the environment can influence the perception of eye colour, the actual colour is determined genetically. Therefore, eye colour in humans usually has a genetic cause.