Pheromone

A pheromone is any chemical produced by a living organism that transmits a message to other members of the same species. There are alarm pheromones, food trail pheromones, sex pheromones, and many others.

Insect pheromones of pest species, such as the Japanese beetle and the gypsy moth, are used to trap them.

In most mammals, pheromones are detected by the vomeronasal organ, or Jacobson's organ, which lies between the nose and mouth, rather than by the nose. Mammals therefore make a face called flehmen when they smell pheromones, in order to direct the pheromone to the VNO.

See also : Quorum sensing