Hair whorl

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Hair whorl
Baby hairy head DSCN2483.jpg
Human baby hair whorl
Details
Latinvortices pilorum
Identifiers
TAA16.0.00.026
FMAFMA:76564
Anatomical terminology
 
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Hair whorl
Baby hairy head DSCN2483.jpg
Human baby hair whorl
Details
Latinvortices pilorum
Identifiers
TAA16.0.00.026
FMAFMA:76564
Anatomical terminology

A hair whorl is a patch of hair growing in the opposite direction of the rest of the hair. Hair whorls occur in most hairy animals, on the body as well as on the head. Hair whorls, also known as crowns, swirls, trichoglyphs, or cowlicks, can be either clockwise or counterclockwise in direction of growth.

In human theories[edit]

Hair whorls on the head (parietal whorls) have been studied by some behaviorists. Most people have clockwise scalp hair-whorls. Parietal whorls which are considered to be normal scalp patterns could be a single whorl or double whorls. Cases of triple parietal whorls are less common but do not necessarily indicate abnormality.[citation needed]

Amar J. S. Klar conducted research to see if there was a genetic link between handedness and hair-whorl direction. He found that 8.4% of right handed people and 45% of left handed people have counterclockwise hair-whorls. His research indicates that a single gene may control both handedness and hair-whorl direction.[1]

Another result concerning handedness of the progeny of discordant monozygotic twins suggests that lefties are one gene apart from righties. Together, these results suggest (1) that a single gene controls handedness, whorl orientation, and twin concordance and discordance and (2) that neuronal and visceral (internal organs) forms of bilateral asymmetry are coded by separate sets of genetic pathways. [2]

Animal behavioral theories[edit]

Main article: Hair whorl (horse)
This horse has an example of two vertical whorls.

There are many (mostly apocryphal) theories concerning horse behavior and their hair whorls.[3]

One paper has suggested that abnormal hair whorls can be used to assess the likelihood of agitated behavior or temperament in cattle in the auction ring.[4]

References[edit]

  1. ^ Human handedness and scalp hair-whorl direction develop from a common genetic mechanism. Klar AJS Genetics 2003 Sep 165(1):269-76 http://www.genetics.org/cgi/reprint/165/1/269.pdf
  2. ^ http://www.genetics.org/content/165/1/269.full
  3. ^ Forsberg Meyer, Jennifer. "What's in a Whorl?" Horse & Rider June 2008: 46-53.
  4. ^ A note on hair whorl position and cattle temperament in the auction ring