For other uses, see.
"Hairy" redirects here. For the epithet, see.
Hair is a that grows from found in the. Hair is one of the defining characteristics of. The human body, apart from areas of glabrous skin, is covered in follicles which produce thick and fine. Most common interest in hair is focused on, hair types, and, but hair is also an important primarily composed of protein, notably.
Attitudes towards different hair, such as and, vary widely across different cultures and historical periods, but it is often used to indicate a person's personal beliefs or social position, such as their age, sex, or religion.
The word "hair" usually refers to two distinct structures:
- the part beneath the skin, called the hair follicle, or, when pulled from the skin, the bulb. This organ is located in the and maintains stem cells, which not only re-grow the hair after it falls hair out, but also are recruited to regrow skin after a wound.
- the shaft, which is the hard filamentous part that extends above the skin surface. A cross section of the hair shaft may be divided roughly into three zones.
Hair fibers have a structure consisting of several layers, starting from the outside:
- the, which consists of several layers of flat, thin cells laid out overlapping one another as roof shingles,
- the, which contains the bundles in cell structures that remain roughly rod-like.
- the, a disorganized and open area at the fiber's center.
Each strand of hair is made up of the,, and. The innermost region, the medulla, is not always present and is an open, unstructured region. The highly structural and organized cortex, or second of three layers of the hair, is the primary source of mechanical strength and water uptake. The cortex contains, which colors the fiber based on the number, distribution and types of melanin granules. The shape of the follicle determines the shape of the cortex, and the shape of the fiber is related to how straight or curly the hair is. People with straight hair have round hair fibers. Oval and other shaped fibers are generally more wavy or curly. The cuticle is the outer covering. Its complex structure slides as the hair swells and is covered with a single molecular layer of lipid that makes the hair repel water. The diameter of human hair varies from 0.017 to 0.18 (0.00067 to 0.00709 in). There are two million small, tubular glands and that produce watery fluids that cool the body by evaporation. The glands at the opening of the hair produce a fatty secretion that lubricates the hair.
Hair growth begins inside the. The only "living" portion of the hair is found in the follicle. The hair that is visible is the hair shaft, which exhibits no biochemical activity and is considered "dead". The base of a hair's root (the "bulb") contains the cells that produce the hair shaft. Other structures of the hair follicle include the oil producing which lubricates the hair and the muscles, which are responsible for causing hairs to stand up. In humans with little body hair, the effect results in.
Root of the hair
The root of the hair ends in an enlargement, the hair bulb, which is whiter in color and softer in texture than the shaft, and is lodged in a follicular involution of the called the. Bulb of hair layers consist of fibrous connective tissue, glassy membrane, external root sheath, internal root sheath composed of epithelium stratum () and granular stratum (), cuticle, cortex and medulla of hair.
Main article:A woman with dark blonde hair, the basal color appears brown due straight hair 2018 to higher levels of brownish eumelanin.
All natural hair colors are the result of two types of hair pigments. Both of these pigments are melanin types, produced inside the hair follicle and packed into granules found in the fibers. is the dominant pigment in and, while is dominant in. is the result of having little in the hair strand. occurs when melanin production decreases or stops, while is hair (and often the skin to which the hair is attached), typically in spots, that never possessed melanin at all in the first place, or ceased for natural genetic reasons, generally, in the first years of life.
Human hair growth
Hair grows everywhere on the external body except for mucus membranes and glabrous skin, such as that found on the palms of the hands, soles of the feet, and lips.
Hair follows a specific growth cycle with three distinct and concurrent phases:,, and phases; all three occur simultaneously - while one strand of hair may be in the anagen phase, another may be in the telogen phase. Each has specific characteristics that determine the length of the hair.
The body has different types of hair, including and, each with its own type of cellular construction. The different construction gives the hair unique characteristics, serving specific purposes, mainly, warmth and protection.
Hair exists in a variety of textures. Three main aspects of hair texture are the curl pattern, volume, and consistency. The derivations of hair texture are not fully understood. All mammalian hair is composed of, so the make-up of is not the source of varying hair patterns. There are a range of theories pertaining to the curl patterns of hair. Scientists have come to believe that the shape of the has an effect on the curliness of the individual's hair. A very round shaft allows for fewer to be present in the hair strand. This means the bonds present are directly in line with one another, resulting in straight hair.
The flatter the hair shaft becomes, the curlier hair gets, because the shape allows more to become compacted together resulting in a bent shape that, with every additional disulfide bond, becomes curlier in form. As the hair follicle shape determines curl pattern, the hair follicle size determines thickness. While the circumference of the hair follicle expands, so does the thickness of the hair follicle. An individual's hair volume, as a result, can be thin, normal, or thick. The consistency of hair can almost always be grouped into three categories: fine, medium, and coarse. This trait is determined by the hair follicle volume and the condition of the strand. Fine hair has the smallest circumference, coarse hair has the largest circumference, and medium hair is anywhere between the other two. Coarse hair has a more open cuticle than thin or medium hair causing it to be the most porous.
There are various systems that people use to classify their curl patterns. Being knowledgeable of an individual's hair type is a good start to knowing how to take care of one's hair. There is not just one method to discovering one's hair type. Additionally it is possible, and quite normal to have more than one kind of hair type, for instance having a mixture of both type 3a & 3b curls.Andre Walker system
The is the most widely used system to classify hair. The system was created by the hairstylist of,. According to this system there are four types of hair: straight, wavy, curly, kinky.
- Type 1 is, which reflects the most sheen and also the most resilient hair of all of the hair types. It is hard to damage and immensely difficult to curl this hair texture. Because the easily spreads from the scalp to the ends without curls or kinks to interrupt its path, it is the most oily hair texture of all.
- Type 2 is wavy hair, whose texture and sheen ranges somewhere between straight and curly hair. Wavy hair is also more likely to become than straight hair. While type A waves can easily alternate between straight and curly styles, type B and C Wavy hair is resistant to styling.
- Type 3 is known to have an S-shape. The curl pattern may resemble a lowercase "s", uppercase "S", or sometimes an uppercase "Z" or lowercase "z". This hair type is usually voluminous, "climate dependent ( = frizz), and damage prone." Lack of proper care causes less defined curls.
- Type 4 is, which features a tightly coiled curl pattern (or no discernible curl pattern at all) that is often fragile with a very high density. This type of hair shrinks when wet and because it has fewer cuticle layers than other hair types it is more susceptible to damage.
This is a method which classifies the hair by curl pattern, hair-strand thickness and overall hair volume.FIA hair classification
CurlinessStraight 1a Stick-straight. 1b Straight but with a slight body wave adding some volume. 1c Straight with body wave and one or two visible S-waves (e.g. at nape of neck or temples). Wavy 2a Loose with stretched S-waves throughout. 2b Shorter with more distinct S-waves (resembling e.g. braided damp hair). 2c Distinct S-waves, some spiral curling. Curly 3a Big, loose spiral curls. 3b Bouncy ringlets. 3c Tight corkscrews. Very ("Really") curly 4a Tightly coiled S-curls. 4b Z-patterned (tightly coiled, sharply angled) 4c Mostly Z-patterned (tightly kinked, less definition)
Thin strands that sometimes are almost translucent when held up to the light. Shed strands can
be hard to see even against a contrasting background; similar to hair found on many people of
Scandinavian descent. You can also try rolling a strand between your thumb and index finger.
Fine hair is difficult to feel or it feels like an ultra-fine strand of silk.
Strands are neither fine nor coarse; similar to hair found on many Caucasians. You can also try
rolling a strand between your thumb and index finger. Medium hair feels like a cotton thread.
You can feel it, but it isn't stiff or rough. It is neither fine nor coarse.
Thick strands whose shed strands usually are easily identified against most backgrounds;
similar to hair found on many people of Asian or Native American descent. You can also try
rolling a strand between your thumb and index finger. Coarse hair feels hard and wiry.
As you roll it back and forth, you may hear it.
by circumference of full-hair ponytail i Thin circumference less than 2 inches (5 centimetres) ii Normal... from 2 to 4 inches (5 to 10 centimetres) iii Thick... more than 4 inches (10 centimetres)
Many mammals have and other hairs that serve different functions. Hair provides thermal regulation and for many animals; for others it provides signals to other animals such as warnings, mating, or other communicative displays; and for some animals hair provides defensive functions and, rarely, even offensive protection. Hair also has a sensory function, extending the sense of touch beyond the surface of the skin. Guard hairs give warnings that may trigger a recoiling reaction.
WarmthPolar bears use their fur for warmth and while their skin is black, their transparent fur appears white and provides camouflage while hunting and serves as protection by hiding cubs in the snow.
While humans have developed clothing and other means of keeping warm, the hair found on the head serves primarily as a source of heat and cooling (when sweat evaporates from soaked hair) as well as protection from ultra-violet radiation exposure. The function of hair in other locations is debated. Hats and coats are still required while doing outdoor activities in cold weather to prevent and, but the hair on the human body does help to keep the internal temperature regulated. When the body is too cold, the muscles found attached to hair follicles stand up, causing the hair in these follicles to do the same. These hairs then form a heat-trapping layer above the. This process is formally called, derived from the Latin words 'pilus' ('hair') and 'erectio' ('rising up'), but is more commonly known as 'having ' in English. This is more effective in other mammals whose fur fluffs up to create air pockets between hairs that insulate the body from the cold. The opposite actions occur when the body is too warm; the arrector muscles make the hair lie flat on the skin which allows heat to leave.
In some mammals, such as and, the hairs have been modified into hard spines or quills. These are covered with thick plates of keratin and serve as protection against predators. Thick hair such as that of the lion's mane and grizzly bear's fur do offer some protection from physical damages such as bites and scratches.
Displacement and vibration of hair shafts are detected by hair follicle nerve receptors and nerve receptors within the skin. Hairs can sense movements of air as well as touch by physical objects and they provide sensory awareness of the presence of. Some hairs, such as eyelashes, are especially sensitive to the presence of potentially harmful matter.
Eyebrows and eyelashesEyelashes and eyebrows help to protect the eyes from dust, dirt, and sweat.
The provide moderate protection to the from, and. They also play a key role in non-verbal by displaying emotions such as sadness, anger, surprise and excitement. In many other mammals, they contain much longer, whisker-like hairs that act as tactile sensors.
The grows at the edges of the eyelid and protects the eye from dirt. The is to humans, camels, horses, ostriches etc., what are to ; they are used to sense when dirt,, or any other potentially harmful object is too close to the eye. The eye reflexively closes as a result of this.
Hair has its origins in the common ancestor of mammals, the, about 300 million years ago. It is currently unknown at what stage the synapsids acquired mammalian characteristics such as and, as the only rarely provide direct evidence for soft tissues. Skin impression of the belly and lower tail of a, possibly shows the basal synapsid stock bore transverse rows of rectangular, similar to those of a modern. An exceptionally well-preserved skull of, a from the, shows smooth, hairless skin with what appears to be glandular depressions, though as a semi-aquatic species it might not have been particularly useful to determine the integument of terrestrial species. The oldest undisputed known fossils showing unambiguous imprints of hair are the (late middle ) and several contemporary, both. More recently, studies on terminal may suggest that non-mammalian synapsids from that era had fur. If this is the case, these are the oldest hair remnants known, showcasing that fur occurred as far back as the latest.
Some modern mammals have a special gland in front of each used to preen the fur, called the. Imprints of this structure are found in the skull of the small early mammals like, but not in their ancestors like.
The hairs of the fur in modern animals are all connected to nerves, and so the fur also serves as a transmitter for sensory input. Fur could have evolved from sensory hair (whiskers). The signals from this sensory apparatus is interpreted in the, a chapter of the brain that expanded markedly in animals like Morganucodon and. The more advanced therapsids could have had a combination of naked skin,, and. A full likely did not evolve until the therapsid-mammal transition. The more advanced, smaller therapsids could have had a combination of hair and scutes, a combination still found in some modern mammals, such as and the.
In varying degrees most have some skin areas without natural hair. On the human body, glabrous is found on the portion of the,, and, which are all parts of the body most closely associated with interacting with the world around us, as are the and. There are four main types of in the glabrous skin of humans:,,, and.
The (Heterocephalus glaber) has evolved skin lacking in general, pelagic hair covering, yet has retained long, very sparsely scattered tactile hairs over its body. Glabrousness is a trait that may be associated with.
The general hairlessness of humans in comparison to related species may be due to loss of functionality in the pseudogene KRTHAP1 (which helps produce keratin) in the human lineage about 240,000 years ago. On an individual basis, mutations in the gene HR can lead to complete hair loss, though this is not typical in humans. Humans may also lose their hair as a result of hormonal imbalance due to drugs or pregnancy.
In order to comprehend why humans are essentially hairless, it is essential to understand that mammalian body hair is not merely an aesthetic characteristic; it protects the skin from wounds, bites, heat, cold, and UV radiation. Additionally, it can be used as a communication tool and as a camouflage. To this end, it can be concluded that benefits stemming from the loss of human body hair must be great enough to outweigh the loss of these protective functions by nakedness.
Humans are the only primate species that have undergone significant hair loss and of the approximately 5000 extant species of mammal, only a handful are effectively hairless. This list includes elephants, rhinoceroses, hippopotamuses, walruses, some species of, whales and other, and naked mole rats. Most mammals have light skin that is covered by fur, and biologists believe that early human ancestors started out this way also. Dark skin probably evolved after humans lost their body fur, because the naked skin was vulnerable to the strong as explained in the. Therefore, evidence of the time when human skin darkened has been used to date the loss of human body hair, assuming that the dark skin was needed after the fur was gone. It was expected that dating the split of the ancestral human louse into two species, the and the, would date the loss of body hair in human ancestors. However, it turned out that the human pubic louse does not descend from the ancestral human louse, but from the, diverging 3.3 million years ago. This suggests that humans had lost body hair (but retained head hair) and developed thick pubic hair prior to this date, were living in or close to the forest where gorillas lived, and acquired pubic lice from butchering gorillas or sleeping in their nests. The evolution of the from the head louse, on the other hand, places the date of clothing much later, some 100,000 years ago.The soft, fine hair found on many nonhuman mammals is typically called fur.
The sweat glands in humans could have evolved to spread from the hands and feet as the body hair changed, or the hair change could have occurred to facilitate sweating. and humans are two of the few animals capable of sweating on most of their body, yet horses are larger and still have fully developed fur. In humans, the skin hairs lie flat in hot conditions, as the arrector pili muscles relax, preventing heat from being trapped by a layer of still air between the hairs, and increasing heat loss by.
Another hypothesis for the thick on humans proposes that played a role (as well as in the selection of long head hair), (see and ), as well as a much larger role of testosterone in men. Sexual selection is the only theory thus far that explains the seen in the hair patterns of men and women. On average, men have more than women. Males have more, especially on the,,, and back, and females have more, which is less visible. The halting of hair development at a juvenile stage, vellus hair, would also be consistent with the evident in humans, especially in females, and thus they could have occurred at the same time. This theory, however, has significant holdings in today's cultural norms. There is no evidence that sexual selection would proceed to such a drastic extent over a million years ago when a full, lush coat of hair would most likely indicate health and would therefore be more likely to be selected for, not against, and not all human populations today have sexual dimorphism in body hair.
A further hypothesis is that human hair was reduced in response to. The "ectoparasite" explanation of modern human nakedness is based on the principle that a hairless primate would harbor fewer parasites. When our ancestors adopted group-dwelling social arrangements roughly 1.8 mya, ectoparasite loads increased dramatically. Early humans became the only one of the 193 primate species to have, which can be attributed to the close living arrangements of large groups of individuals. While primate species have communal sleeping arrangements, these groups are always on the move and thus are less likely to harbor ectoparasites. Because of this, selection pressure for early humans would favor decreasing body hair because those with thick coats would have more lethal-disease-carrying ectoparasites and would thereby have lower fitness.
Another view is proposed by, who attempts to explain hairlessness as evolved from the relationship between mother and child, and as a consequence of. Giles also connects romantic love to hairlessness.
Another hypothesis is that humans' use of fire caused or initiated the reduction in human hair.
Evolutionary biologists suggest that the genus arose in approximately 2.5 million years ago. They devised new hunting techniques. The higher protein diet led to the evolution of larger body and brain sizes. 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 evolved the ability to sweat: a process which was facilitated by the loss of body hair. A major problem with this theory, however, is that it does not explain why males are larger, hairier, and were more active in hunting than females. The female-male size differential among other closely associated primates is much greater than among humans, and therefore it was reduced during human evolution. Other primates have sweat gland in their armpits that function as those of humans, and thus it is probable that human sweat glands evolved from a similar distribution, spreading to more areas of the body, rather than occurring through evolution of a new trait. It is not known whether the increased distribution of sweat glands occurred before, during, or after, the change in body hair, or even whether the two are related developments. Horses also sweat, and they are larger, hairier, and expend more energy running than human males, so there may not be any connection between the ability to sweat and the apparent hairlessness of humans.
Another factor in human evolution that also occurred in the prehistoric past was a preferential selection for, particularly in females. The idea that adult humans exhibit certain neotenous (juvenile) features, not evinced in the great apes, is about a century old. made a long list of such traits, and published a short list in. In addition, characteristics in women are often in. For instance, is a juvenile characteristic. However, while men develop longer, coarser, thicker, and darker through, women do not, leaving their vellus hair visible.
Curly hairYellow curly hair and scalp from body which had long black wig over hair. Parts of wig plait remains. From Egypt, Gurob, probably tomb 23. 18th–19th Dynasty. The Petrie Museum of Egyptian Archaeology, London
Jablonski asserts head hair was evolutionarily advantageous for pre-humans to retain because it protected the scalp as they walked upright in the intense African (equatorial). While some might argue that, by this logic, humans should also express hairy shoulders because these body parts would putatively be exposed to similar conditions, the protection of the head, the seat of the brain that enabled humanity to become one of the most successful species on the planet (and which also is very vulnerable at birth) was arguably a more urgent issue (axillary hair in the underarms and groin were also retained as signs of sexual maturity). Sometime during the gradual process by which Homo erectus began a transition from furry skin to the naked skin expressed by Homo sapiens, hair texture putatively gradually changed from straight hair (the condition of most mammals, including humanity's closest cousins—chimpanzees) to or 'kinky' (i.e. tightly coiled). This argument assumes that curly hair better impedes the passage of UV light into the body relative to straight hair (thus curly or coiled hair would be particularly advantageous for light-skinned hominids living at the equator).
It is substantiated by Iyengar's (1998) findings that UV light can enter into straight human hair roots (and thus into the body through the skin) via the hair shaft. Specifically, the results of that study suggest that this phenomenon resembles the passage of light through fiber optic tubes (which do not function as effectively when kinked or sharply curved or coiled). In this sense, when hominids (i.e. Homo Erectus) were gradually losing their straight body hair and thereby exposing the initially pale skin underneath their fur to the sun, straight hair would have been an adaptive liability. By inverse logic, later, as humans traveled farther from Africa and/or the equator, straight hair may have (initially) evolved to aid the entry of UV light into the body during the transition from dark, UV-protected skin to paler skin.
Some conversely believe that tightly coiled hair that grows into a typical Afro-like formation would have greatly reduced the ability of the head and brain to cool because although African people's hair is much less dense than its European counterpart's, in the intense sun the effective 'woolly hat' that such hair produced would have been a disadvantage. However, such anthropologists as oppositely argue about this hair texture. Specifically, Jablonski's assertions suggest that the adjective "woolly" in reference to Afro-hair is a in connoting the high heat insulation derivable from the true wool of sheep. Instead, the relatively sparse density of Afro-hair, combined with its springy coils actually results in an airy, almost sponge-like structure that in turn, Jablonski argues, more likely facilitates an increase in the circulation of cool air onto the scalp. Further, wet Afro-hair does not stick to the neck and scalp unless totally drenched and instead tends to retain its basic springy puffiness because it less easily responds to moisture and sweat than straight hair does. In this sense, the trait may enhance comfort levels in intense equatorial climates more than straight hair (which, on the other hand, tends to naturally fall over the ears and neck to a degree that provides slightly enhanced comfort levels in cold climates relative to tightly coiled hair).
Further, some interpret the ideas of as suggesting that some traits, such as hair texture, were so arbitrary to human survival that the role natural selection played was trivial. Hence, they argue in favor of his suggestion that sexual selection may be responsible for such traits. However, inclinations towards deeming hair texture "adaptively trivial" may root in certain cultural value judgments more than objective logic. In this sense the possibility that hair texture may have played an adaptively significant role cannot be completely eliminated from consideration. In fact, while the sexual selection hypothesis cannot be ruled out, the asymmetrical distribution of this trait vouches for environmental influence. Specifically, if hair texture were simply the result of adaptively arbitrary human aesthetic preferences, one would expect that the global distribution of the various hair textures would be fairly random. Instead, the distribution of Afro-hair is strongly skewed toward the equator.
Further, it is notable that the most pervasive expression of this hair texture can be found in sub-Saharan Africa; a region of the world that abundant genetic and paleo-anthropological evidence suggests, was the relatively recent (200,000-year-old) point of origin for modern humanity. In fact, although genetic findings (Tishkoff, 2009) suggest that sub-Saharan Africans are the most genetically diverse continental group on Earth, approaches ubiquity in this region. This points to a strong, long-term selective pressure that, in stark contrast to most other regions of the genomes of sub-Saharan groups, left little room for genetic variation at the determining loci. Such a pattern, again, does not seem to support human sexual aesthetics as being the sole or primary cause of this distribution.Straight black hair
The EDAR locus
A group of studies have recently shown that genetic patterns at the EDAR locus, a region of the modern human genome that contributes to hair texture variation among most individuals of East Asian descent, support the hypothesis that (East Asian) straight hair likely developed in this branch of the modern human lineage subsequent to the original expression of tightly coiled. Specifically, the relevant findings indicate that the EDAR mutation coding for the predominant East Asian 'coarse' or thick, straight hair texture arose within the past 65,000 years, which is a time frame that covers from the earliest of the 'Out of Africa' migrations up to now.
is a that targets hairy skin.
is another condition that results in greying before the age of 20 years in Whites, before 25 years in Asians, and before 30 years in Africans.
Hair care involves the and of hair including hair on the, facial, and other body hair. Hair care routines differ according to an individual's culture and the physical characteristics of one's hair. Hair may be colored, trimmed, shaved, plucked, or otherwise removed with treatments such as waxing, sugaring, and threading.
is the removal of hair from the surface of the skin. This can be achieved through methods such as. is the removal of the entire hair strand, including the part of the hair that has not yet left the follicle. A popular way to epilate hair is through.
ShavingMany razors have multiple blades purportedly to ensure a close shave. While shaving initially will leave skin feeling smooth and hair free, new hair growth can appear a few hours after hair removal.
is accomplished with bladed instruments, such as. The is brought close to the skin and stroked over the hair in the desired area to cut the terminal hairs and leave the skin feeling smooth. Depending upon the rate of growth, one can begin to feel the hair growing back within hours of shaving. This is especially evident in men who develop a after having shaved their faces. This new growth is called. Stubble typically appears to grow back thicker because the shaved hairs are blunted instead of tapered off at the end, although the hair never actually grows back thicker.
involves using a sticky wax and strip of paper or cloth to pull hair from the root. Waxing is the ideal hair removal technique to keep an area hair-free for long periods of time. It can take three to six weeks for waxed hair to begin to resurface again. Hair in areas that have previously been waxed also is known to grow back finer and thinner, especially compared to hair that has been shaved with a razor.
Laser hair removal is a cosmetic method where a small beam pulses selective heat on dark target matter in the area that causes hair growth without harming the skin tissue. This process is repeated several times over the course of many months to a couple of years with hair regrowing less frequently until it finally stops; this is used as a more permanent solution to or. Laser removal is practiced in many clinics along with many at-home products.
Cutting and trimming
Because the hair on the head is normally longer than other types of body hair, it is cut with or. People with longer hair will most often use scissors to cut their hair, whereas shorter hair is maintained using a trimmer. Depending on the desired length and overall health of the hair, periods without cutting or trimming the hair can vary.
Cut hair may be used in. Global imports of hair in 2010 was worth $US 1.24 billion.
See also:Portrait of a Woman, Alessandro Allori (1535–1607; ): a plucked hairline gives a fashionably "noble brow"
Hair has great social significance for. It can grow on most external areas of the, except on the palms of the and the soles of the feet (among other areas). Hair is most noticeable on most people in a small number of areas, which are also the ones that are most commonly trimmed,, or. These include the,,, eyebrows,, and, as well as the. The highly visible differences between male and female body and facial hair are a notable.
The world's longest documented hair belongs to Xie Qiuping (China), at 5.627 m (18 ft 5.54 in) when measured on 8 May 2004. She has been growing her hair since 1973, from the age of 13.
Indication of status
Healthy hair indicates health and youth (important in ). Hair color and texture can be a sign of ethnic ancestry. is a sign of in men. White hair is a sign of age or genetics, which may be concealed with (not easily for some), although many prefer to assume it (especially if it is a characteristic of the person since childhood). Male pattern is a sign of age, which may be concealed with a, hats, or religious and cultural adornments. Although drugs and medical procedures exist for the treatment of baldness, many balding men simply shave their heads. In early modern China, the queue was a male hairstyle worn by the Manchus from central Manchuria and the Han Chinese during the Qing dynasty; hair on the front of the head was shaved off above the temples every ten days, mimicking male-pattern baldness, and the rest of the hair braided into a long pigtail.
may be an indicator of group membership. During the, the followers of decided to crop their hair close to their head, as an act of defiance to the curls and ringlets of the king's men. This led to the Parliamentary faction being nicknamed. Recent isotopic analysis of hair is helping to shed further light on sociocultural interaction, giving information on food procurement and consumption in the 19th century. Having was popular among the in the 1920s as a sign of rebellion against traditional roles for women. Female art students known as the "cropheads" also adopted the style, notably at the Slade School in London, England. Regional variations in cause practices regarding hair on the arms and legs to differ. Some religious groups may follow certain rules regarding hair as part of religious observance. The rules often differ for men and women.
Many subcultures have hairstyles which may indicate an unofficial membership. Many, and Indian have, as well many older. Many wear a hairstyle known as a or other spiked and dyed hairstyles; have short-cropped or completely shaved heads. Long stylized bangs were very common for, and younger in the 2000s and early 2010s, among people of both.
Heads were shaved in, and head-shaving has been used as, especially for women with long hair. The shaven head is common in haircuts, while Western monks are known for the. By contrast, among some Indian holy men, the hair is worn extremely long.
In the time of Confucius (5th century BCE), the Chinese grew out their hair and often tied it, as a symbol of filial piety.
Regular hairdressing in some cultures is considered a sign of wealth or status. The of the were despised early in the movement's history. In some cultures, having one's hair cut can symbolize a liberation from one's past, usually after a trying time in one's life. Cutting the hair also may be a sign of mourning.
Tightly coiled hair in its natural state may be worn in an. This hairstyle was once worn among as a symbol of racial pride. Given that the coiled texture is the natural state of some African Americans' hair, or perceived as being more "African", this simple style is now often seen as a sign of self-acceptance and an affirmation that the beauty norms of the () dominant culture are not absolute. It is important to note that African Americans as a whole have a variety of hair textures, as they are not an ethnically homogeneous group, but an ad-hoc of different racial admixtures.
The film (1969) includes the assumption that the two main characters could have their long hairs forcibly shaved with a rusty razor when jailed, symbolizing the intolerance of some conservative groups toward members of the. At the conclusion of the, the defendants had their heads shaved by the police, causing public outcry. During the appeal trial, they appeared in the dock wearing wigs. A case where a 14-year-old student was expelled from school in in the mid-2000s, allegedly because of his haircut, sparked national debate and legal action resulting in compensation.
Women's hair may be hidden using, a common part of the in and a symbol of modesty required for certain religious rituals in. requires all married women to wear headscarves inside the church; this tradition is often extended to all women, regardless of marital status. also commands the use of scarves and other head coverings for married women for modesty reasons. Certain sects also wear head scarves for religious reasons. have an obligation not to cut hair (a Sikh cutting hair becomes 'apostate' which means fallen from religion) and men keep it tied in a bun on the head, which is then covered appropriately using a. Multiple religions, both ancient and contemporary, require or advise one to allow their hair to become, though people also wear them for fashion. For men, Islam, Orthodox Judaism, Orthodox Christianity, Roman Catholicism, and other religious groups have at various times recommended or required the covering of the head and sections of the hair of men, and some have dictates relating to the cutting of men's facial and head hair. Some Christian sects throughout history and up to modern times have also religiously proscribed the cutting of women's hair. For some, the donning of a or is a form of.
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