(1960), and Sharma (1985) collected similar data. Schwarzburg (1927), Kloepfer (1946), Beckman et al. However, if the myth were true, two parents with counterclockwise whorls could not have a child with a clockwise whorl, so the three CW children of CCW x CCW parents do not fit the myth. He concluded that hair whorl was a simple Mendelian trait, with the allele for clockwise whorl dominant to the allele for counterclockwise whorl. Family studiesīernstein (1925) compared parents and offspring, with the following results (omitting double whorls): Parents Ucheya and Igweh (2005), however, identified a whorl in all 500 of their sample of Nigerian men. Wunderlich and Heerema (1975) could see a hair whorl in only 10 percent of black newborns, and Ziering and Krenitsky (2003) reported that 80 percent of African-American men had a diffuse pattern instead of a whorl. Long, fine hair sometimes assumes a false whorl but the true whorl can always be located close to the scalp." Ziering and Krenitsky (2003) reported that 78 percent of women had what they called a "diffuse" pattern instead of a whorl. Lauterbach (1925) says "frequently the hair requires considerable combing in order to discover the natural whorl. The whorl can be particularly hard to see in people with long or curly hair. (2009) had two people independently judge photographs of whorls, and for about 4 percent of subjects, one observer called the whorl clockwise while the other called it counterclockwise. The direction of the whorl can be difficult to determine. Wunderlich and Heerema (1975) found double whorls in 1.5 percent of white newborns, while Ucheya and Igweh (2005) found double whorls in 2 percent of Nigerian men. Some people have two or more whorls Lauterbach and Knight (1927) found 5 percent of white Massachusetts schoolchildren to have double whorls, while Schwarzburg (1927) found 5.4 percent of Germans to have double whorls. Clockwise whorls are most common estimates of the frequency of clockwise whorls range from 51 percent in Japan (Klar 2009) to 65 percent of undergraduate psychology students in the United Kingdom (Annett 1985), 69 percent of Nigerians (Ucheya and Igweh 2005), 74 percent of German schoolboys (Bernstein 1925), 81 percent of students in the United States (Lauterbach and Knight 1927), 92 percent of the "general population" in Maryland (Klar 2003), and 94 percent of newborns in the United States (Wunderlick and Heerema 1975). In people with short, straight hair, a single whorl is usually fairly obvious. Other studies have given conflicting results, and it is not clear yet whether there is any relationship between hair-whorl direction and either handedness or sexuality. While hair whorl is occasionally used to illustrate basic genetics, it gets more attention because some studies have suggested that counterclockwise whorls are more common in left-handed people than in right-handed, and other studies have suggested that counterclockwise whorls are more common in gay men than in straight men. Several studies have data that fit this myth fairly well, but with enough exceptions that the myth can't be completely true. This is sometimes used to illustrate basic genetics the myth is that whorl direction is controlled by a single gene with two alleles, and the allele for clockwise is dominant to the allele for counterclockwise. When viewed from above and behind the head, many people's hair whorls in either a clockwise (CW) or counterclockwise (CCW) direction. Clockwise hair whorl counterclockwise hair whorl.
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