Phéromone

The phéromones are substances emitted by the majority of the animals and unquestionable vegetable, and which act like messengers on individuals of the same species. Extremely active, they act as infinitesimal quantities, so that they can be detected, or even transported, with several kilometers. At the Mammalian S and the Reptile S, the phéromones are detected by the voméro-nasal Organe, while the Insecte S generally use their antennas.

The phéromones are chemical substances comparable with the Hormone S. But, while the traditional hormones (Insuline, Adrénaline, etc) are produced by the endocrine glands and circulate only inside the organization while taking part in its Métabolisme, the phéromones are generally produced by glands exocrines, or are secreted with the Urine, and serve chemical messengers between individuals. They can be volatile (perceived by the Odorat), or act by contact (cuticular compounds of the insects for example, perceived by the gustatory receivers). They play a central role during the periods of coupling, and at some social Insecte S, the such Fourmi S or the Abeille S. These phéromones is essential to the good performance of the group. The sexual phéromones of the insects contribute to reproductive insulation between the species thanks to their specificity. In addition, it was thought a long time that the voméro-nasal body, very active in the animals, did not function at the man; however, several studies proved the opposite. The biochemists can henceforth produce phéromones of synthesis. __TOC

Etymology and definition

The term of phéromones was defined by the Biochimiste German Peter Karlson and the Entomologiste Swiss Martin Lüscher in 1959 starting from the Greek roots:
  • pherein (to transport) and
  • hormon (to excite).
Thus, the phéromones were defined like: “ of the substances secreted by individuals and who, received by other individuals of the same species, cause a specific reaction, a behavior or a biological modification ”.

Different the phéromones

One distinguishes two types and seven classes from phéromones intervening in the chemical communication, and primarily definite starting from the insects:
  • Standard a: phéromones inciting. They act on the behavior
  • Type b: phéromones modifying. They act on biology

; 1. Phéromones of territory: Deposited in the environment, they delimit a territory. At canidés, these hormones are contained in the urines which the individuals deposit on reference marks, those serving to some extent as “terminals” to mark their “territory”.

; 2. Phéromones of trace: They are very current in the social insects: the ants, for example, mark out their tracks by hormones of trace - in fact, hydrocarbons not-birds.

; 3. Phéromones of alarm: In fact volatile substances released by an individual in the event of attack by a predator, and start the escape (plant louses) or the aggression (bee) at the other individuals of the same species. The phéromones also exist in the vegetable world: certain plants, when they are grazed, emit phéromones of alarm; the neighbors react then by producing tannins which return them less appétants for the herbivore, so that this one must often change place.

; 4. Phéromones sexual: In the animals for example, the sexual phéromones indicate the availability of the females to be fertilized. Certain butterflies detect a sexual partner with more than 10 kilometers.

; 5. Phéromones epideictic, or of “spacing”: Recognized in the insects, they are different from the phéromones of territory. “The females which lay their eggs in these fruits deposit these mysterious substances in the vicinity of their laying to announce it to the other females of the same species: so all stupidly which they will lay elsewhere.” (H. Fabre)

; 7. Phéromones of aggregation: Produced by one or the other sex, they attract the individuals of the two sexes.

; 8. Others phéromones (not yet classified): This classification, founded on the effects induced on the behavior, remains still too surface, and the phéromones fill many other functions.

  • Phéromones de Nasanov (worker bees)
  • Phéromones royal of the bee…
  • Phéromones of appeasing (mammals)

Main features

According to the animal species, one finds phéromones in the Peau, certain dermic glands (sébacées, sudoripares), the Salive, the expired air, secretions of the urogenital ways, secretions Vagin ales (primates), the anal glands, the Urine S or the Fèces.

The phéromones are generally perceived by the Organe voméronasal (also called body of Jacobson), but at the Mammifère S some are perceived by the principal olfactive system: the last lucky finds show that one second family of olfactive receivers, the TAARS, would seem to recognize the male phéromones in the mice.

The signal phéromonal can be made up of one or several molecules (bouquet phéromonal), emitted simultaneously or successively. The phéromones exist in volatile or soluble form; they arrive in contact with the sensory cells either by inhalation, or after a physical contact. A substance emitted by an organization can be related to another molecule, a conveyer, or be transformed (for example by a bacterial action), before becoming a phéromone.

The phéromones can be carboxylic acid saturated, Stéroïde S, Aldéhyde S, Ester S, Cétone S, alcohols and others made up.

Human phéromones

At the man, the phéromones can be secreted in the Sueur apocrine axillaire and périnéale (androstene and androsténol) and in the part prostatic of the Sperme (spermine and spermidine).

At the woman, the phéromones can be secreted in sweat apocrine axillaire, mamelonnaire and périnéale, and in secretions Vagin ales produced by the Glande S atriales and of Skene (short chains of Fatty-acid).

In the mankind, the most significant effects of the phéromones are physiological, as for example the synchronization of the menstrual cycles of the women who live in community (Weller 1993).

One also observes some effects emotion nels, but quasi no effect Comportement Al For example, compared to the Sexualité, none the molecules tested induced or started a sexual behavior. The most interesting results relate to the exposure to the Androgène S, but with extremely contradictory results. It was thus shown that the experimental exposure to the Androsténol increases among women the duration of their social contact with the men (Cowley 1991). The molecule does not cause the behavior of reproduction, but it makes it possible to initiate it by supporting the bringing together heterosexual. But of other experiments showed that the induced Androsténone on the contrary, at the women, of the negative emotional reactions towards the men (Filsinger 1985), that the men produce simultaneously the two molecules, and that the olfactive effect of the androsténone is stronger than that of the androsténol (Maiworm 1990): the total effect, in situation " naturelle" , should then be repulsive.

In conclusion, the effect of the phéromones is weak in the mankind, and it is especially physiological.

At the Mammalian S, the reduction in the importance of the phéromones since the Rongeur S to the Man is coherent with neuroanatomical reality : in the rodents, the olfactive structures represent a third of the Cerveau, while, at the Man, they represent nothing any more but some pourcents; three quarters of the human Brain being dedicated to the cognitive functions.

Phéromones in the various human relations

Relations between a mother and her child

There are two functions of the body odors in the relation between a mother and her social child one and the other physiological one. Indeed the phéromones help to restore a social relation: they make it possible the mother to establish a relation with its newborn. When with the baby, it develops an olfactive attachment with the making safe contact of the maternal body. For the physiological relation the phéromones regularize the metabolism of the child: as there are glands apocrines around the nipples, the odors which emerge some give appetite to the child. The orsqu' a woman sprinkles artificial perfume, the child refuses the center because he does not recognize any more the olfactive message which starts the reflex camera of téter.

Thus we can say that the phéromones play a part in this relation as much from the social point of view that physiological.

Homosexual relations

One can highlight the homosexual behavior thanks to a phéromone present in male perspiration. To know if the activation induced by the phéromones corresponds to an sexual orientation, the researchers compared the activity of the brain of homosexual men with those of men and women heterosexuals. They could observe that the male phéromones activated the hypothalamus of the brain of the hétérosxuelles women and the men homosxuels whereas the female phéromones activated only the hypothalamus of the men heterosexuals

One can thus say thanks to neurology that the perception and the action of the phéromones on the human ones depend on their sexual orientation. They are only consequences of the sexual orientation of the person who perceives them.

Hétérosexuelles relations

A study showed that the hamsters were clearly attracted by the odor from nonrelated abroad, they use the odor not to be coupled with close relatives. The bond between the diversity of the odors and genetic diversity was clearly established. It more specifically relates to a whole of genes which is at the origin of the recognition. The phéromones play a part while transporting genetic arrangement and the health of a potential reproductive partner. These genes among are diversified, constituting a genetic signature. They thus give to each individual a single odor which can be detected.

Similar studies at the men showed that the properties quoted previously are applicable to the human ones. The phéromones thus have an influence on the choice of or the sexual partner.

See too

Bibliographical references

  • COWLEY J.J., BROOKSBANK B.W. : Human putative exposure to pheromones and exchanges in aspects off social behavior. Newspaper off steroid biochemistry and molecular biology, 39/4B: 647-659, 1991
  • FILSINGER EE, BRAUN JJ, MOUNTS WC. Year examination off the effects off putative pheromones one human judgments. Ethol Sociobiol, 6:227 - 36, 1985
  • FOIDART A., LEGROS J.J., BALTHAZART J.: Human phéromones: animal vestige or not recognized reality. Medical check of Liege, 49/12: 662-680, 1994
  • MAIWORM RE. Off influence androstenone, androstenol, menstrual cycle, and oral contraceptive one the attractivity ratings off female probands. Paper presented At the Ninth Congress off ECRO; 1990
  • MEREDITH Michael: Human vomeronasal function: critical review off best and worst boxes has. Chemical judicious, 26:433 - 445, 2001
  • WELLER Leonard, WELLER Aron: Human menstrual synchrony: critical has assessment. Neuroscience and biobehavioral reviews, 17:427 - 439, 1993

Internal bonds

External bonds

  • the phéromones
  • phéromones of the queens

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