Monday, June 30, 2008

Natural Hair Colors

Natural hair colors
Natural hair color is black, brown, blonde, or red, depending on a person's ethnic origins. Hair color is genetically associated with certain skin tones and eye colors.

Black hair

Black hair is the darkest and most common color of human hair. Black hair is found in people of all backgrounds and ethnicities. It has large amounts of eumelanin and is less dense than other hair colors. It can be a very dark brown. Black hair is known to be the shiniest out of all other hair colors.[1] In English, black hair is usually described as "jet-black", "raven black", rather than "brunette".
Outside of Europe, many humans have black or dark brown hair. [2] This is likely the original hair color of Homo sapiens, and is found in its greatest distribution in sub-Saharan Africa, Asia, and the pre-Columbian Americas. Among White people, black hair is particularly common in people of Southern European, e.g.: Greek, Spanish, Portuguese, and Italian ancestry. Black hair is less prominent in people from Nordic countries. In Africa, many individuals have blond, reddish, brown and black hair colors, as well.
Black hair comes in a variety of textures. Many people of African descent have diverse hair textures ranging from afro-textured hair, to straight, curly or wavy.. Straight black hair is common in Asians and Native Americans, as well. Curly, wavy, straight and coarse hair textures are common among all racialized groups. Within African populations, hair textures vary greatly. This is due to the fact that individuals of African descent have the most ancient alleles (genes responsible for specific physical traits) and the greatest genetic diversity.

Brown hair

Brown hair is the second most common hair color, with black being the most common.
A girl with long brown hair
Brown hair (also referred to as chestnut and cinnamon) varies from light brown to almost black hair. It is characterized by higher levels of the dark pigment eumelanin and lower levels of the pale pigment phaeomelanin. Its strands are thicker than those of fair hair but not as much as those of red hair. People with brown hair are often referred to as brunettes, the feminine form, and brunets (silent t), the masculine term. Brown hair is commonly termed “dark” because of its darker characteristics than that of its blonde or red haired counterparts.

Blond hair

Blond hair ranges from nearly white (platinum blond, tow-haired) to a dark golden blond. Strawberry blond, a mixture of blond and red hair found predominantly in Ireland, is an especially rare type containing the most phaeomelanin. Blond hair can have almost any proportions of phaeomelanin and eumelanin, but both only in small amounts. More phaeomelanin creates a more golden blond color, and more eumelanin creates an ash blond. Blond hair is common in many European peoples, but rare among others. Many children born with blonde hair may develop darker hair as they age.

Red hair

Red hair (also referred to as auburn, ginger or titian) varies from a deep orange-red through burnt orange to bright copper. It is characterized by high levels of the reddish pigment pheomelanin and relatively low levels of the dark pigment eumelanin. People with red hair are often referred to as redheads.[1] Approximately 1% to 2% of the human population has red hair.[2][3] It occurs more frequently (between 2% and 6% of the population) in northern and western Europeans, and their descendants, and at lower frequencies throughout other parts of Europe, Asia and Africa. Red hair appears in people with two copies of a recessive gene on chromosome 16 which causes a change in the MC1R protein. It is associated with fair skin color, freckles, and sensitivity to ultraviolet light, as the mutated MC1R protein is found in the skin and eyes instead of the darker melanin. Cultural reactions have varied from ridicule to admiration; many common stereotypes exist regarding redheads, and they are often portrayed as the “fiery-tempered redhead”.
As well as in humans, red hair can be found in other mammalian species such as orangutans, squirrels, goats, and highland cattle. Red hair or fur can be found in some breeds of dog and cat, and certain species of fox and deer.

Gray and white hair

Gray hair color typically occurs naturally as people age (see "Effects of aging on hair color", below). The same can be said for white hair. In some cases, gray hair may instead be caused by a deficiency of B12 or a thyroid imbalance

article source From Wikipedia, the free encyclopedia

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