Natural hair color is determined by the type and amount of melanin present in the hair follicles. While eumelanin produces brown and black pigments, pheomelanin produces red and yellow pigments. The interplay and concentration of these pigments result in a spectrum of hair colors, some of which occur far less frequently than others. For example, naturally occurring red hair is found in only 1-2% of the global population.
Understanding the genetic and biochemical basis of rare hair colors provides insights into human diversity and the complex interplay of genetics and phenotypic expression. Historically, certain hair colors have been associated with specific cultural or regional groups, sometimes leading to social stigmas or even persecution. Scientifically, studying these variations can contribute to knowledge about pigment disorders, genetic inheritance patterns, and potentially even broader medical applications.