Pheromones

Pheromones are chemical substances that are naturally emitted by insects, animals, and plants. These substances signal an animal's presence to other members of the same species, and are used for purposes such as marking territory, signaling an alarm, or as sexual signals.

History of Pheromones

The first pheromone was identified in 1956 by German scientists studying silkworms. Studies showed that the pheromone acted as a very strong sexual attractant for male silkworms.

Later work investigated the presence, and effects, of pheromones in mammals, including humans. Work with hamsters has shown that there appears to be pheromones in female hamsters that act as a sexual attractant to male hamsters. Research with humans suggests that pheromones may have effects on humans, but the precise nature and effect is not precisely known.

There are a variety of recognized uses for pheromones in insects, animals, and plants. Pheromones are the substance in some animal urine that is used to mark their territory. Ants use pheromones to mark trails that lead to food. Species such as aphids release pheromones as a signal for flight. Some plants release alarm pheromones when they are grazed upon that cause neighboring plants to produce tannins, making them less appetizing to grazing animals. Some insects use pheromones as a signal for members of both sexes to gather at a given place.

Pheromones and Humans

Despite the lack of scientific knowledge about pheromones and humans, there is a sizeable market for products advertised as pheromones that can enhance sexual attraction in humans. There are also several theories about how pheromones might affect human sexual reactions. For instance, pheromones have been suggested as the reason there seems to be an instant “chemistry” between some couples. There is also a theory that pheromones help to detect whether a potential mate is a close relation or not.

There has only been one rigorous study suggesting a sexually related pheromone effect in humans. That was a study showing that a group of women living together tended to start having menstrual cycles at the same time of month. Although that effect has been widely attributed to pheromones, other plausible explanations have also been given.

Pheromones and Pest Control

Pheromones are commercially used to control some insect populations in crops. One technique involves the use of pheromones to attract insects to a location where they are killed. A second technique relies on mating disruption. Mating disruption involves spreading pheromones that will attract males over a wide area. Disruption of mating occurs because males will then have trouble actually finding females among all the false pheromone signals.

By Charles Hair