Human hair color account for all possible shades of brown, blond, or red (for example, platinum blond versus dark blond/light brown), nor does it explain why hair color sometimes darkens as a person ages. Several gene pairs control the light versus dark hair color in a cumulative effect. A person's genotype for a multifactorial trait can interact with the environment to produce varying phenotypes (see quantitative trait locus). Natural hair color can be brown, blond, black, red, or white; all natural hair colors including grey, white and lightest blond, are shades of brown. The Fischer–Saller scale, named after Eugen Fischer and , is
Monochromatic color Monochromatic color Monochromatic colors are all the colors (tones, tints and shades ) of a single hue. Monochromatic color schemes are derived from a single base hue and extended using its shades, tones and tints. Tints are achieved by adding white and shades and tones are achieved by adding a darker color, grey or black. Monochromatic color schemes provide opportunities in art and visual communications design as they allow for a greater range of contrasting tones that can be used to attract attention, create focus and support legibility. The use of a monochromatic color provides a strong sense of visual