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Natural hair, black hair, and afro-textured hair are terms used to refer to the texture of Black African hair that has not been altered chemically (by perming, relaxing, straightening, bleaching or coloring). Not all people of Black African descent have naturally afro-textured hair, although the overwhelming majority do. In particular, certain groups such as the Fulani of West Africa have a few members with hair that ranges from straight to loosely coiled due to admixture with non-Black African populations.

Nonetheless, among non-admixed Black Africans, tightly coiled, Afro-hair is a ubiquitous trait. Adjectives such as “hard”, “kinky”, “nappy”, or “woolly” are also used to describe natural Afro-textured hair. This hair is typically tightly coiled and soft to the touch. It is generally thicker and denser than other textures, more hair growing per unit area. Additionally, each strand is gnarled and almost wirey making the growth notably coarsely textured. Andamanese Negritos and most Melanesian people also have tightly coiled hair.

Contents 1 Adaptation 1.1 The context in which Afro hair texture arose 1.2 The evolution of Afro hair texture 1.3 The global distribution of Afro hair texture 2 History in the United States 3 Controversy over natural hair in the United States 4 See also 5 External links 6 References

Adaptation

Tightly coiled hair is typically described as being an evolutionary adaptation to the warm, tropical climates of sub-Saharan Africa and Melanesia. Some hold that the texture may allow for greater cooling because sweat is able to remain on the scalp.¹ Furthermore it has been asserted that, when the sun is directly overhead, the top surface of the hair heats up while leaving a barrier of cooler air between the scalp and the top surface of the hair. This barrier of cooler air assists in cooling the brain. This effect is most prominent in people with 'frizzy' (Afro-textured) hair.² Despite these claims, the fact remains that a large proportion of people who currently occupy equatorial regions (such as those from India or indigenous South America) do not express natural Afro-hair. Thus it is likely that this trait evolved to serve a different original purpose.

The context in which Afro hair texture arose

Evolutionary biologists suggest that the genus Homo arose in East Africa approximately 2.5 million years ago.² During this time new hunting techniques were innovated.² The higher protein diet led to the evolution of larger body and brain sizes.² In Skin: A Natural History, Nina Jablonski postulates that increasing body size, in conjunction with intensified hunting during the day at the equator, gave rise to a greater need to rapidly expel heat. As a result, humans developed the ability to sweat and thus lost body hair to facilitate this process.² Notably, Pagel et al (2003) argue against this hypothesis, stating that hominids without fur would not have been able to warm themselves as efficiently at night, nor protect themselves well enough from the sun during the day. However, it is likely that increased intelligence, combined with sophisticated hunting techniques, enabled humans to warm themselves at night using animal skins. Furthermore, as the furless condition slowly developed, genetic evidence suggests that dark skin color gradually evolved to protect the body from UV during the day (and thus compensate for the sparse hair coverage). Thus, it is likely that pre-humans lost fur mostly for the purpose of facilitating the evaporation of sweat and the corresponding cooling of the body.

The evolution of Afro hair texture

Jablonski agrees that it was evolutionarily advantageous for pre-humans (Homo erectus of ~2 million years ago) to retain the hair on their heads in order to protect the skin there as they walked upright in the intense African (equatorial) UV light. Auxiliary hair in the groin and underarms was likely retained as a sign of sexual maturity. During the process of going from fur to naked skin, hair texture putatively changed gradually from being straight (the condition of most mammals, including humanity's closest cousin--the chimpanzee), to Afro-like or 'kinky' (ie tightly coiled). This is made clear in a study by Iyengar (1998) which has provided evidence that the roots of straight human hair may act as optic fibers that allow UV light to pass into the skin. In this sense, during the period in which pre-humans were gradually losing most of their straight body hair (fur) and thereby exposing the probably pale skin underneath their fur to the sun (Rogers et al, 2004), straight hair would have been an evolutionary liability. 'Kinks' in fiber optic tubes are known to prevent UV from passing through. Hence, tightly coiled or 'kinky' hair may have evolved to prevent the entry of UV light during the gradual process of evolution toward dark skin and the simultaneous transition from hairiness to virtual nudity. Later, after a group of modern humans left Africa approximately 60,000 years ago, straight hair re-evolved among those members who migrated to northern Eurasia (see hair texture--'The Evolution of Straight Hair').

The global distribution of Afro hair texture

Afro hair is a predominant characteristic of Black Africans, Andaman Islanders, and Melanesians. It is often posited that this hair texture (which is unique among all mammals--and most humans) is an adaptation to tropical climates. However, as mentioned, many (dark skinned) straight haired people have also been found to thrive in similar types of warm equatorial environments. Thus the distribution of the trait likely has more to do with the migration and admixture patterns of those who left Africa to populate the rest of the world within ~60,000 years ago (Quintana-Murci et al, 2004). It also has to do with the retention of that which was adaptively essential at the equator (ie dark skin) and the loss of that which was no longer essential (ie Afro hair) following admixture. Specifically, after the migration of a group of modern humans out of Africa, those who settled in warm sunny regions similar to sub-Saharan Africa, like the Andaman Islands and Melanesia (and, in addition, remained isolated from straight haired northern migrants) did not experience adaptive (nor admixture) pressure for their hair to straighten. Thus it remained Afro-like.

Nonetheless, in places like India, South America, Australia, and Polynesia, hair is straight despite warm, UV-rich climates. This is explainable given the context in which Afro-hair likely arose, which is described above. To reiterate, this unique texture likely evolved 1-2 million years ago, just before the time that dark skin (Harding et al, 2000) is estimated to have arisen (as indicated by human MC1R genetic demographic patterns--see Harding 2000). The trait may have reached high frequency in order to compensate for the gradual process in which relatively pale hominid (pre-human) skin was being exposed to the African equatorial sun as it lost its protective fur (see Rogers et al 2004). This feature may have been advantageous in this context because, in light of the Iyengar (1998) finding that straight human hair may act as fiber optic tubes, it is likely that coiled hair slows and/or prevents the entry of UV radiation (and possibly other forms of radiation such as heat/ultra red) into the skin in a way analogous to how "kinks" attenuate (scatter) light moving through actual fiber optic tubes.

Once dark skin evolved ~1 million years ago (Harding, 2000), Afro-hair texture was less crucial in terms of protection from UV rays. However, some hold that it was likely sustained in the population because, as mentioned, it had the capacity to prevent UV (and possibly heat) from entering the body (or in this case, head). Alternatively, the trait may have sustained high frequencies in the founding/original (African) human population simply due to the fact that, over the 1-2 million years of its existence, most of the various genes that determine it likely retained phenotypic monomorphism in the population due to the genetotypic dominance of coiled/curled hair genes over straight hair genes. In other words, an ancient selective sweep likely occurred for these genes while skin was darkening 1-2 million years ago. This change was sustained due to high levels of inter-African admixture, and/or the genetic dominance of the factors determining the phenotype. Notably, sexual selection is another possible factor that cannot be completely ruled out. However, it seems unlikely that the distinct populations occupying the entire sub-Saharan region of Africa would all have the same taste with regards to hair texture.

In addition, because, as mentioned, inter-mixture within the large sub-Saharan African population remained relatively high for a significant portion of its pre-history (compared to those who migrated outside of this region), severe, sustained isolation and its associated intensive inbreeding (i.e. bottlenecks) did not occur there (Tishkoff, 1996). Thus, straight hair did not arise by way of random mutation and isolation (i.e. genetic drift) among any of the subgroups of the sub-Saharan region. In fact, it is very likely, given the basically ubiquitous distribution of the Afro-hair trait among contemporary sub-Saharan Africans (the most genetically diverse macroethnicgroup on earth whose direct ancestors comprised the original population from which all of humanity derived), that at one time the Afro-hair trait characterized the entire human population (i.e. before the exodus from Africa and the settlement of some of the migrants in northern Eurasia).

After the re-evolution of straight hair among those who migrated from Africa to northern Eurasia ~50-60,000 years ago (see hair texture--'The Evolution of Straight Hair'), there is evidence suggesting that small but continual (or large episodic) migrations occurred from Central Europe into India (Kivisild et al, 2003). It is therefore likely that this accumulation of northern genes (determining straight hair texture and certain facial features) over the past ~30-40,000 years eventually resulted the expression of straight hair throughout India in conjunction with dark skin (which was sustained due to natural selection to protect against UV). Polynesian, Australian, and South American populations are also known to have been influenced (either slightly or entirely) by Northern migrants. For example, in the case of Australia (and likely India), when northerners arrived, they intermixed with the dark skinned, Afro-haired inhabitants of the region (Redd & Stoneking, 1999; Windshuttle & Gillin, 2003) giving rise to a (possibly sexual) selective sweep for straight hair and dark skin.

Presuming that natural Afro-hair was the initial texture of anatomically modern humanity, and that groups that migrated to northern latitudes were the sources of genes expressing straight hair, the following migration and/or admixture scenarios are supported. In the case of Polynesians and South American Indians, archaeological and genetic evidence suggest that straight haired migrants of northern East Asian descent were the first to populate these regions (Diamond, 2005). This made them the predominant inhabitants until modern times. Thus, straight hair (combined with relatively dark skin) likely came to dominate among certain equatorial groups due to pre-Holocene waves of migration into these areas from the north. Further, in the case of India and Australia, admixture occurred which resulted the replacement of Afro-haired genes yet the maintenance of dark skin color due to natural selection for UV protection.

In this sense, Afro-hair texture is likely a remnant of a crucial time in hominid evolutionary history (i.e. when humans became hairless to enable perspiration) (see Iyengar, 1998 in light of Rogers et al, 2004 and Harding et al, 2000), The trait ceased to be essential to survival at the equator upon the evolution of hairless dark skin. This explains why dark skinned straight haired (i.e. northern admixed) groups are able to survive in UV-rich regions (such as India, Australia, Polynesia, and South America) without expressing tightly coiled (Afro) hair texture.

History in the United States

African Americans have been experimenting with ways to style their hair before the nineteenth century. Between the late 1890s and the early 1900s, Annie Malone, Madam C. J. Walker and Garrett Augustus Morgan revolutionized African American hair care by inventing and marketing chemical applications to alter the natural tightly curled texture. During the 1930s, conking (vividly described in "The Autobiography of Malcolm X") became an innovative method in the U.S. for Black men to straighten kinky hair.

It has been debated whether these practices arose out of a desire to make the hair more manageable or instead to conform to a Eurocentric standard of beauty.^{citation needed} Supporters of the second theory believe that the same prejudice that viewed lighter skin as preferable to darker, held that straight or wavy hair was preferable to tightly curled hair; that this prejudice comes not from African diasporic peoples but from European slaveholders and colonizers as part of the rhetoric used to support slavery and racially-based social class stratifications. Some claim that the dominant prejudice for Eurocentric ideas of beauty pervades the western world.³

The civil rights movement and black power and pride movements of the 1960s and 1970s in the U.S. created an impetus for African Americans to express their political commitments and self love through the wearing of natural hair. This contributed to the emergence of the Afro hairstyle into American mainstream culture, as an affirmation of Black African heritage, that "black is beautiful," and a rejection of Eurocentric standards of beauty. It has been used in songs, as a symbol of Black African heritage, notably in I Wish by Stevie Wonder. By the 1970s natural hair had evolved into a popular hairstyle.

Over the years, the popularity of natural hair has waxed and waned, but a significant percentage, approximately 75% of African American women still elect to straighten their hair with relaxers of some kind. Prolonged application of such chemicals can result in overprocessing, breakage and thinning of the hair.

In the past decade or so, natural hair has once again increased in popularity with the emergence of styles such as cornrows, locks, braiding, twists and cropped hair, most of which originated in Ancient Africa^{citation needed}. With the emergence of hip-hop culture and Caribbean influences like reggae music, more non-blacks have begun to wear these hairstyles as well. There has been a boom in marketing hair products such as "Out of Africa" shampoo to African American consumers. Slogans that promote a pan-Black African appreciation of Afro-textured hair include "Happy to be nappy," "Don't worry, be nappy," as well as "Love, peace and nappiness."

Most black women in the West, however, continue to relax their hair.³ Even today, people are sometimes discouraged in the workplace from wearing their hair in a natural style.^{citation needed} Notably, the American marketing strategies that have inspired Black women throughout the diaspora to straighten their hair are now being directed at Black Africans. Thus in many urban areas of the continent, and increasingly in some rural areas, straightened hair is common among adult females.

Controversy over natural hair in the United States

Although there has been a reemergence of natural hair, there is still the underlying tone that straightened hair is a more acceptable or professional hairstyle. This is evidenced by the fact that high-profile black women in professions such as journalism and politics still wear straight hair.

A 1998 incident became national news when a teacher in Bushwick, Brooklyn, introduced her students to the book Nappy Hair by African American author Carolivia Herron. The teacher, who is white, was criticized by parents of black children, who thought that the book presented a negative stereotype.⁴

On Wednesday, April 4, 2007 radio talk-show host Don Imus referred to the Rutgers University women's basketball team playing in the Women's NCAA Championship game as a group of "nappy-headed hos" during his Imus in the Morning show. Bernard McGuirk then compared the game to "the jigaboos versus the wannabes," alluding to Spike Lee's film School Daze. Imus apologized two days later, after receiving criticism. CBS Radio canceled Don Imus' morning show on Thursday, April 12, 2007.

During August 2007, American Lawyer Magazine reported that an unnamed junior Glamour Magazine staffer did a presentation on the "Do's and Don't's of Corporate Fashion" for Cleary Gottlieb, a New York City law firm. There was a slide show where the woman made negative remarks about black women's natural hairstyles in the workplace, calling them "shocking," "inappropriate," and "political." Both the law firm and Glamour Magazine issued apologies to the staff.⁵⁶

See also

• Afro
• Cornrows
• Dreadlocks
• Conk
• Jheri curl

External links

References

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