How is the Insect World Influenced by Terpenes?

Many insects metabolize the terpenes that they receive from plants to create growth hormones and pheromones which in turn help them navigate their world.  Pheromones are scent based luring and signal compounds that insects and other organisms (including animals) secrete in order to communicate with others like them, i.e. to warn (alarm pheromones), to mark food resources and their location (trace pheromones), as well of assembly places (aggregation pheromones) and to attract sexual partners for copulation (sexual pheromones).  Without the terpene scents to trigger the attraction and sexual mating processes many species of insects and animals would face certain doom.