||This article needs additional citations for verification. (March 2013)|
Goose bumps, also called goose flesh, goose pimples, the medical term cutis anserina, are the bumps on a person's skin at the base of body hairs which may involuntarily develop when a person is cold or experiences strong emotions such as fear, nostalgia, pleasure, euphoria, awe, admiration and sexual arousal.
The reflex of producing goose bumps is known as arasing, piloerection, or the pilomotor reflex. It occurs in many mammals besides humans; a prominent example is porcupines, which raise their quills when threatened, or sea otters when they encounter sharks or other predators.
Other creatures get goose bumps for the same reason, for example this is why a cat or dog’s hair stands on end. In cold situations, the rising hair traps air between the hairs and skin, creating insulation and warmth. In response to fear, goose bumps make an animal appear larger – hopefully scaring away the enemy.
The phrase "goose bumps" derives from the phenomenon's association with goose skin. Goose feathers grow from stores in the epidermis which resemble human hair follicles. When a goose's feathers are plucked, its skin has protrusions where the feathers were, and these bumps are what the human phenomenon resembles.
It is not clear why the particular fowl, goose, was chosen in English, as most other birds share this same anatomical feature. Some authors have applied "goose bumps" to the symptoms of sexually-transmitted diseases. Certainly being "bitten by a Winchester goose" was a common euphemism for syphilis in the 16th century. "Winchester geese" was the nickname for the prostitutes of South London, licenced by the Bishop of Winchester in the area around his London palace.
However, this seductive etymology does not explain why many other languages use the same bird as in English. "Goose skin" is used in German (Gänsehaut), Italian (pelle d'oca), Russian (гусиная кожа), Ukrainian (гусяча шкіра), Polish (gęsia skórka), Czech (husí kůže), Slovak (husia koža), Danish and Norwegian (gåsehud), Latvian (zosāda) and Hungarian (libabőr).
It should be noted that in other languages, however, the "goose" may be replaced by other kinds of poultry. For instance, "hen" is used in Spanish (piel de gallina), Portuguese (pele de galinha), Romanian (piele de găină) and French (chair de poule). "Chicken" is used in Dutch (kippenvel), Chinese (雞皮疙瘩, lit. lumps on chicken skin), Finnish (kananliha), Afrikaans (hoendervleis) and Korean (닭살, daksal). In Hindi/Urdu it is called rongtey khade ho jaana. The equivalent Japanese term, 鳥肌, torihada, translates literally as "bird skin". In Arabic, it is called kash'arirah, in Hebrew it is called simply "duck skin" (עור ברווז).
All of the birds listed above are commonly consumed in the country of origin, so it may well be assumed that the term "goose bumps" (also "goose skin" and "goose flesh", c.1785 and 1810) and all other related terms in other languages came into being merely due to the visual similarity of the bird's plucked skin and the human skin phenomenon, used to describe the sensation in a way that is readily familiar. 
Anatomy and biology 
Goose bumps are created when tiny muscles at the base of each hair, known as arrector pili muscles, contract and pull the hair erect. The reflex is started by the sympathetic nervous system, which is responsible for many fight-or-flight responses.
As a response to cold: in animals covered with fur or hair, the erect hairs trap air to create a layer of insulation. Goose bumps can also be a response to anger or fear: the erect hairs make the animal appear larger, in order to intimidate enemies. This can be observed in the intimidation displays of chimpanzees, some New world monkeys like the cotton-top tamarin, in stressed mice and rats, and in frightened cats. In humans, it can even extend to piloerection as a reaction to hearing nails scratch on a chalkboard, listening to awe-inspiring music, or feeling or remembering strong and positive emotions (e.g., after winning a sports event). During the formation of goose bumps, the body is warmed from the muscle tension in piloerection.
In humans, goose bumps are strongest on the forearms, but also occur on the legs, neck, and other areas of the skin that have hair. In some people, they even occur in the face or on the head.
Piloerection is also a classic symptom of some diseases, such as temporal lobe epilepsy, some brain tumors, and autonomic hyperreflexia. Goose bumps can also be caused by withdrawal from opiates such as heroin. A skin condition that mimics goose bumps in appearance is keratosis pilaris.
Extreme temperatures 
Goosebumps can be experienced in the presence of cold temperatures. The stimulus of cold surroundings causes the tiny muscles attached to each hair follicle to contract. This contraction causes the hair strands to literally "stand on end." At the same time, the tiny muscles that are contracting are causing a "bunching" of the skin surrounding the hairs, which results in the "bumps" in goosebumps.
This is the body's way of preserving its own heat by causing the hairs on the skin to stand up, thus reducing heat loss. Goosebumps are often seen in conjunction with shivering in these instances.
People also get goosebumps when they are hot, or in the presence of extreme heat. The main reason for this is sweat. As the perspiration accumulates on the skin, it naturally evaporates. As the sweat evaporates, it cools down the skin surface. As this process occurs, a dramatic temperature difference occurs and the body responds to the "chill" of the evaporation of the sweat and the "goosebump response" kicks in.
Intense emotion 
People often say they feel their "hair standing on end" when they are frightened or in awe. Another intense emotional situation that can cause goosebumps is the "fight or flight" response the body can employ in an extremely stressful situation. As the body prepares itself for either fighting or running, the sympathetic nervous system floods the blood with adrenaline (epinephrine), a hormone that speeds up heart rate, metabolism, and body temperature in the presence of extreme stress. The sympathetic nervous system also causes a reflex called piloerection, which makes the muscles attached to the base of each hair follicle contract and force the hair up. Goose bumps cause the hairs to stand up, just as porcupines raise their quills when threatened.
See also 
|Wikimedia Commons has media related to: Goose bumps|
- "Science of Music: Why Does Music Give Me Goose Bumps? | Exploratorium". Exploratorium.edu. Retrieved 2013-05-14.
- Roberts, Chris (2004), Heavy words lightly thrown: the reason behind the rhyme, Granta, p. 24, ISBN 978-1-86207-765-2
- Buret, Frédéric (1895), -0rq[jrgtg[94t5[j4th[924ghw4[otgegoibjertohjw9itjh955gjb hue8rhgwiernjgpuwerge4 w5gjwn4rgmqeg qoiejr0ggoog Syphilis to-day and among the ancients v. 2-3], F.A. Davis, p. 48
- Buret, Frédéric (1895), Syphilis to-day and among the ancients v. 1, F.A. Davis, p. 62 dates the aforementioned manuscript to the 16th century
- Wabuda, Susan (2002), Preaching during the English Reformation, Cambridge studies in early modern British history, Cambridge University Press, p. 127, ISBN 978-0-521-45395-0
- Online Etymology Dictionary - "Goose bumps"
- Martin Muller and John Mitan. Conflict and Cooperation in Wild Chimpanzees. Advances in the Study of Behavior, vol. 35
- French and Snowdon. Sexual dimorphism in responses to unfamiliar intruders in the tamarin, Saguinus oedipus. Animal Behaviour (1981) vol. 29 (3) pp. 822-829
- Masuda et al. Developmental and pharmacological features of mouse emotional piloerection. Experimental Animals, 1999 Jul;48(3):209-11. PMID 10480027
- David Huron. Biological Templates for Musical Experience: From Fear to Pleasure. Abstract
- George A. Bubenik. Why do humans get "goosebumps" when they are cold, or under other circumstances? 
- Scientific American - "Why do humans get goosebumps when they are cold, or under other circumstances?"