432 Insects produce a wide range of semiochemicals that affect the behavior and/or phys iology of other animals. The semiochemicals include pheromones, kairomones, and allomones. Pheromones induce behavioral or developmental responses in other individuals of the same species. They may be volatile, exerting their influence over considerable distance, or non-volatile when they are spread by physical contact (especially trophallaxis) among individuals. They include (1) sex pheromones, which modify reproductive behavior or development; (2) caste-regulating pheromones, which determine the proportion of different castes in colonies of social insects; (3) aggregation pheromones, which attract insects to a common feeding and/or mating site; (4) alarm pheromones, which warn of impending danger; (5) trail-marking pheromones, which provide information on the location and quantity of food available to a colony of social insects; and (6) spacing pheromones that maintain optimum population density. Kairomones and allomones exert their effect on other species, inducing effects beneficial to the receiver and emitter, respectively. Kairomones are of special significance to many predators and parasitoids, which use pheromones released by their prey as cues enabling them to locate the host. Allomones are used principally as defensive chemicals, released when the emitter is under attack; however, in a few species the allomones may be used aggressively to lure prey to the emitter or, in some ants and bees, to confuse the host, enabling the emitter to rob or take over the nest.

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

Get My Free Ebook

Post a comment