Pheromone

Jump to navigation Jump to search

WikiDoc Resources for Pheromone

Articles

Most recent articles on Pheromone

Most cited articles on Pheromone

Review articles on Pheromone

Articles on Pheromone in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Pheromone

Images of Pheromone

Photos of Pheromone

Podcasts & MP3s on Pheromone

Videos on Pheromone

Evidence Based Medicine

Cochrane Collaboration on Pheromone

Bandolier on Pheromone

TRIP on Pheromone

Clinical Trials

Ongoing Trials on Pheromone at Clinical Trials.gov

Trial results on Pheromone

Clinical Trials on Pheromone at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Pheromone

NICE Guidance on Pheromone

NHS PRODIGY Guidance

FDA on Pheromone

CDC on Pheromone

Books

Books on Pheromone

News

Pheromone in the news

Be alerted to news on Pheromone

News trends on Pheromone

Commentary

Blogs on Pheromone

Definitions

Definitions of Pheromone

Patient Resources / Community

Patient resources on Pheromone

Discussion groups on Pheromone

Patient Handouts on Pheromone

Directions to Hospitals Treating Pheromone

Risk calculators and risk factors for Pheromone

Healthcare Provider Resources

Symptoms of Pheromone

Causes & Risk Factors for Pheromone

Diagnostic studies for Pheromone

Treatment of Pheromone

Continuing Medical Education (CME)

CME Programs on Pheromone

International

Pheromone en Espanol

Pheromone en Francais

Business

Pheromone in the Marketplace

Patents on Pheromone

Experimental / Informatics

List of terms related to Pheromone

Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [6] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.

Fanning honeybee exposes Nasonov gland (white-at tip of abdomen) releasing pheromone to entice swarm into an empty hive

Overview

A pheromone is a chemical that triggers a natural behavioral response in another member of the same species. There are alarm pheromones, food trail pheromones, sex pheromones, and many others that affect behavior or physiology. Their use among insects has been particularly well documented, although many vertebrates and plants also communicate using pheromones.

Explanation

Pheromones of the Raydon Cheadle Navarro insect species, such as the Japanese beetle and the gypsy moth, can be used to induce many behaviors. This facilitates trapping for monitoring purposes and population control by creating confusion, disrupting mating and preventing them from laying eggs.

In mammals and reptiles, pheromones may be detected by the vomeronasal organ, or Jacobson's organ, which lies between the nose and mouth and is the first stage of the accessory olfactory system. Some pheromones in these animals are detected by regular olfactory membranes.

The term "pheromone" was introduced by Peter Karlson and Martin Lüscher in 1959, based on the Greek pherein (to transport) and hormon (to stimulate). They proposed the term to describe chemical signals from conspecifics which elicit innate behaviours soon after Butenandt characterized the first such chemical, Bombykol (a chemically well-characterized pheromone released by the female silkworm to attract mates).[1]

Types of pheromones

Aggregation pheromones

Produced by one or the other sex, these pheromones attract individuals of both sexes.

Alarm pheromones

Some species release a volatile substance when attacked by a predator that can trigger flight (in aphids) or aggression (in bees) in members of the same species. Pheromones also exist in plants:certain plants emit alarm pheromones when grazed upon, resulting in tannin production in neighboring plants. These tannins make the plants less appetizing for the herbivore.

Epideictic pheromones

Recognized in insects, these pheromones are different from territory pheromones. According to Fabre (translated from French), "Females who lay their eggs in these fruits deposit these mysterious substances in the vicinity of their clutch to signal to other females of the same species so that they will clutch elsewhere."

Aggregation of nymphs of bugs

Releaser pheromones

Powerful attractant molecules that some organisms may use to attract mates from a distance of 2 miles or more. This type of pheromone generally elicites rapid response but is quickly degraded. In contrast, a primer pheromone would have a slower onset but a longer duration.

Primer pheromones

These pheromones trigger a change of developmental events.

Territorial pheromones

Laid down in the environment, these pheromones mark the boundaries of an organism's territory. In dogs, these hormones are present in the urine, which they deposit on landmarks serving to mark the perimeter of the claimed territory.

Trail pheromones

These pheromones are common in social insects. For example, ants mark their paths with these pheromones, which are non-volatile hydrocarbons.

Certain ants lay down an initial trail of pheromones as they return to the nest with food. This trail attracts other ants and serves as a guide.[2] As long as the food source remains, the pheromone trail will be continually renewed. The pheromone must be continually renewed because it evaporates quickly. When the supply begins to dwindle, the trailmaking ceases. In at least one species of ant, trails that no longer lead to food are also marked with a repellent pheromone.[3]

Sex pheromones

Sesiidae on a pheromone trap

In animals, sex pheromones indicate the availability of the female for breeding. Many insect species release sex pheromones to attract a mate and many lepidopterans can detect a potential mate from as far away as 10 km (6.2 miles). Pheromones can be used in gametes to trail the opposite sex's gametes for fertilization. Pheromones are also used in the detection of oestrus in sows. Boar pheromones are sprayed into the sty, and those sows which exhibit sexual arousal are known to be currently available for breeding.

Male animals also emit pheromones that convey information about what species they are, and their genotype. The purpose of pheromones giving information about genotype is a mechanism to avoid inbreeding. Females are attracted to males with the least similar genotype, which means they are attracted to males who are the least likely to be related to them. An exception to this is when the female is pregnant. Then they are most drawn to individuals with the most similar pheromones (and therefore genotype) most likely because they want to keep family close by to aid with the raising of their young and to take advantage of protection.

Other pheromones (not yet classified)

This classification, based on the effects on behavior, remains artificial. Pheromones fill many additional functions.

  • Nasonov pheromones (worker bees)
  • Royal pheromones (bees)
  • Calming (appeasement) pheromones (mammals)

Human pheromones

A few well-controlled scientific studies have been published suggesting the possibility of pheromones in humans. The best-studied case involves the synchronization of menstrual cycles among women based on unconscious odor cues (the so called McClintock effect, named after the primary investigator). This study proposes that there are two types of pheromone involved: "One, produced prior to ovulation, shortens the ovarian cycle; and the second, produced just at ovulation, lengthens the cycle". This is analogous to the Whitten effect,[4][5] a male pheromone mediated modulation of estrus observed in mice.

Other studies have suggested that people might be using odor cues associated with the immune system to select mates who are not closely related to themselves. (See Disassortative sexual selection) Using a brain imaging technique, Swedish researchers have shown that homosexual and heterosexual males' brains respond differently to two odors that may be involved in sexual arousal, and that the homosexual men respond in the same way as heterosexual women. The study was expanded to include lesbian women and the results were consistent with previous findings meaning that homosexual women were not as responsive to male identified odors but their response to female cues was similar to heterosexual males.[6] According to the researchers, this research suggests a possible role for human pheromones in the biological basis of sexual orientation.[7] Another study demonstrated that the smell of androstadienone, a chemical component of male sweat, maintains higher levels of cortisol in females. The scientists suggest that the ability of this compound to influence the endocrine balance of the opposite sex makes it a human pheromonal chemosignal.[8]

In 2006 it was shown that a second mouse receptor sub-class is found in the olfactory epithelium. Called the trace amine-associated receptors (TAAR), some are activated by volatile amines found in mouse urine, including one putative mouse pheromone.[9] Orthologous receptors exist in humans providing, the authors propose, evidence for a mechanism of human pheromone detection.[10]

Some commercially-available substances are advertised using claims that the products contain human sexual pheromones and can act as an aphrodisiac. These often lack credibility due to an excessive marketing of pheromones by unsolicited e-mail. Despite claims to the contrary, no defined pheromonal substance has ever been demonstrated to directly influence human behavior in a peer reviewed, published study.[11]

See also

Further reading

  • Kohl, JV., Atzmueller, M., Fink, B. & Grammer, K. (2001). Human Pheromones: Integrating Neuroendocrinology and Ethology. Neuroendocrinology Letters, 22(5), 319-331. Full text
  • Liberles, S.D., Buck, L.B. (2006). A second class of chemosensory receptors in the olfactory epithelium. Nature, 442, 645-50.
  • McClintock, M.K. (1984). Estrous synchrony: modulation of ovarian cycle length by female pheromones. Physiological Behavior, 32, 701-705.
  • Wilson, E. O., Bossert, W. H. (1963). Chemical communication among animals. Recent Progress in Hormone Research, 19, 673-716.
  • Wyatt, Tristram D. (2003). Pheromones and Animal Behaviour: Communication by Smell and Taste. Cambridge: Cambridge University Press. ISBN 0-521-48526-6.

External links

References

  1. Karlson, P., Lüscher, M. (1959). Pheromones: a new term for a class of biologically active substances. Nature 183, 55-56.
  2. "Excited ants follow pheromone trail of same chemical they will use to paralyze their prey". Retrieved 2006-03-14.
  3. "Study: Ants Use Scents Like Road Signs". Retrieved 2006-03-14.
  4. Whitten, M.K. 1957. Effect of exteroceptive factors on the oestrous cycle of mice. Nature. 180(4599):1436. [1]
  5. Gangrade BK, Dominic CJ. 1984. Studies of the male-originating pheromones involved in the Whitten effect and Bruce effect in mice. Biol Reprod. 31(1):89-96.[2]
  6. Savic, I."Brain response to putative pheromones in lesbian women." PNAS, May 16, 2006
  7. Wade, N. "Gay Men are found to have Different Scent of Attraction." NY Times, May 9, 2005
  8. Wyart C, Webster WW, Chen JH, Wilson SR, McClary A, Khan RM, Sobel N. 2007. Smelling a single component of male sweat alters levels of cortisol in women. J Neurosci. 27(6):1261-5.[3]
  9. Liberles SD, Buck LB. 2006. A second class of chemosensory receptors in the olfactory epithelium. Nature. 442(7103):645-50. [4]
  10. Pearson H. 2006. Mouse data hint at human pheromones. Nature. 442(7102):495. [5]
  11. Wyatt, Tristram D. (2003). Pheromones and Animal Behaviour: Communication by Smell and Taste. Cambridge: Cambridge University Press. ISBN 0-521-48526-6.

ar:فرمون bg:Феромон ca:Feromona da:Feromon de:Pheromon el:Φερομόνη gl:Feromona id:Feromon it:Feromone he:פרומון lt:Feromonas nl:Feromoon no:Feromon su:Féromon fi:Feromoni sv:Feromon

Template:WH Template:WS Template:Jb1