Chemical ecology concerns the biochemicals (called semiochemicals) produced and released by organisms that have physiological and behavioral effects on other organisms.
Studies in chemical ecology are often interdisciplinary (integrating several fields of science such as chemistry and ecology) but also more specific areas in biochemistry (such as biosynthesis of compounds), molecular biology, or physiology (reception of the compounds and transmission of nerve impulses), as well as in behavioral ecology (orientation movements of an organism) and population ecology (aggregation and competition of organisms) and even the interactions among trophic levels (such as predator-prey interactions). Evolutionary studies at all these levels are of interest to understand how stable the semiochemical systems are and whether adaptations to new systems are constrained.
Chemical ecology studies span investigations both at the basic level, where the natural mechanisms are endeavored to be understood, and at the applied or practical level, where manipulation of the natural mechanisms is attempted in order to reduce damage by man's insect pests. Our group studies primarily insects and the pheromone chemicals they use to communicate various information to others of the same species. Other semiochemicals studied include interspecific warning chemicals (allomones) as well as plant compounds that attract or repel insects.
Semiochemicals must be isolated and identified before subsequent ecological and evolutionary studies can be undertaken. This means that biologists and chemists must cooperate to find, among hundreds of compounds, the usually trace amounts of one or a few chemicals important to behavior. The pheromone components can then be synthesized commercially and used as lures in traps or as a "fog" to confuse the insects so that they are unable to find mates or host plants. The great advantage of pheromones and semiochemicals is that they are not highly toxic like most pesticides, and pheromones are effective in extremely small quantities of only a few grams per ha (100 by 100 meters) per season. Also, while beneficial insects like honey bees and general insect predators are killed by insecticides, they and other non-target organisms are unaffected by pheromones since only the target (pest) species takes any notice of its own behaviorally active chemicals.
John A. Byers
