In humans worldwide, East Asian-textured hair is the most common, whereas kinky hair is the least common. Afro-textured hair has a flattened cross-section and is finer, and its ringlets can form tight circles with diameters of only a few millimeters. East Asiatic heads of straight hair are formed from almost-round hair follicles producing straight hair, and European hair follicle forms oval shapes which produce wavy hair. The cross-section of a hair is an ellipse, which can tend towards a circle or be distinctly flattened. An individual hair's shape is never completely circular. The shape of the hair follicle determines the hair's curliness. The more coiled the hair texture, the higher its shrinkage. Shrinkage is most evident when afro-textured hair is (or has recently been) wet. In addition, due to a phenomenon called 'shrinkage', kinky hair that is a given length when stretched straight can appear much shorter when allowed to naturally coil. Loussourarn found that afro-textured hair grows at an average rate of approximately 256 micrometers per day, whereas European-textured straight hair grows at approximately 396 micrometers per day. This was significantly lower than that of European hair, which, on average, has approximately 227 hairs per square centimeter. Specifically, the average density of afro-textured hair was found to be approximately 190 hairs per square centimeter. Classical afro-textured hair has been found to be not as densely concentrated on the scalp as other follicle types. have found that black hair may differ in the distribution of lipids throughout the hair shaft. With regard to structure, all human hair has the same basic chemical composition in terms of keratin protein content. ĭifferent genetic groups have observable differences in the structure, density, and growth rate of hair. Those variations include pattern (mainly tight coils), pattern size (watch spring to chalk), density (sparse to dense), strand diameter (fine, medium, coarse), and feel (cottony, woolly, spongy). However, afro-textured hair is often difficult to categorize because of the many different variations among individuals. The Andre Walker Hair Typing System classifies afro-textured hair as 'type 4' (there are other types of hair, defined as type 1 for straight hair, type 2 for wavy, and type 3 for curly, with the letters A, B, and C used as indicators of the degree of coil variation in each type), with the subcategory of type 4C being most exemplary of the afro-textured hair. In 1997, hairstylist Andre Walker created a numerical grading system for human hair types. Jean Baptiste Bory de Saint-Vincent in 1825 introduced the scientific term Oulotrichi for the purpose of human taxonomy. More formally, ulotrichous ('curly-haired' from Ancient Greek: οὖλος, romanized: oûlos, lit.'crisp, curly' and Ancient Greek: θρίξ, romanized: thríx, lit.'hair') refers to afro-textured hair, its antonym being leiotrichous ('smooth-haired'). Terminology Įnglish adjectives such as woolly, kinky, or spiraled have been used to describe natural afro-textured hair. The overall effect is such that, contrasted with straight hair, wavy hair, or curly hair, afro-textured hair appears denser. Each strand of this hair type grows in a tiny, angle-like helix shape. 1868Īfro-textured hair is a human hair texture originally prevalent in many regions with hot climates, including in sub-Saharan Africa. Woman from the island of Nosy Be, in Madagascar, c.
Human hair texture originating from sub-Saharan Africa
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