Black hair

Black hair is the darkest and most common of all human hair colors globally, due to larger populations with this dominant trait. It is a dominant genetic trait, and it is found in people of all backgrounds and ethnicities. It has large amounts of eumelanin and is less dense than other hair colors.[1] In English, black hair is sometimes described as soft-black, raven black, or jet-black. The range of skin colors associated with black hair is vast, ranging from the palest of light skin tones to dark skin. Black-haired humans can have dark or light eyes.

Distribution

This hair color is found in its greatest distribution among peoples of Asia, pre-Columbian Americas and Africa. Black-haired people with either dark or light-colored eyes, are also common among the Indo-European and non-Indo-European ethnic groups in Western Asia, Central Asia, Afghanistan and South Asia. Black hair is also common in people of Eastern Europe and Southern Europe regardless of ethnolinguistic affiliation. For example, although brown hair is the dominant type, some Southern Europeans are particularly noted for their straight or wavy black hair, and it can be combined with either dark (such as brown) or light (such as green, gray or blue) colored eyes.

Though this characteristic can also be seen in people of the United Kingdom and Northwestern Europe, it is less common.[2] People of Celtic heritage in Ireland with such traits are sometimes known as the "Black Irish".[3]

Hair is naturally reflective, so black hair is not completely dark in bright light. However, the darkest shade will not have a warm, neutral tone but a sheen which can seem almost blue, like the iridescence of a raven's wing; hence, sometimes referred to as raven-black.

Genetics

People with Amerindian or East Asian ancestry have thicker and straighter hair. The reason is because these populations have the Derived EDAR gene allele that is linked to thicker and straighter hair. The derived EDAR gene arose approximately 30,000 years ago in China.[4] a recent study shows that paleo amerindians had both variants of the EDAR gene, the derived G-allele and the ancestral A-allele. when they tested ancient DNA remains found in the Americas of the individuals named USR1, aBrazil_LapaDoSanto_9600BP and aBrazil_Laranjal_6700BP the results showed that they carried the ancestral A-allele.

While the remains of Cuncaicha and Lauricocha 2 ancient individuals from South America dating back 11,000 years ago share alleles at the highest rate with present-day amerindians. that means the derived G-allele increased in frequency in parallel with the ancestral A-allele.[5]

See also

References

  1. Frost, Peter. "Why Do Europeans Have So Many Hair and Eye Colors?" (summarizing Frost, P. 2006. European hair and eye color - A case of frequency-dependent sexual selection? Evolution and Human Behavior 27:85-103)
  2. The Distribution of Anthropological Traits in Europe, Bertil Lundman: The Races and Peoples of Europe (New York 1977)
  3. Hornbeck, Shirley Elro (2000-01-01). This and that Genealogy Tips. Genealogical Publishing Com. ISBN 9780806350271.
  4. "Amerindians and Asians carry a version of the EDAR gene that is linked to thicker hair shafts".
  5. "Reconstructing the Deep Population History of Central and South America".

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