Life History and Habits

Phasmids are sedentary insects whose ability to escape from would-be predators is largely dependent on their close resemblance to twigs or leaves. However, they do possess a number of other devices that can be brought into operation should they be detected. These include falling to the ground and entering a cataleptic state, in which they may avoid further detection, secretion of an obnoxious material from the repugnatory glands, and reflex autotomy between the femur and trochanter should a leg be seized. Many phasmids are nocturnal, and during the day may remain completely immobile. Typically they are green or brown insects but the color of different populations of the same species may vary considerably. A few species exhibit density-dependent phase polymorphism analogous to that in locusts. It should be emphasized, however, that the behavioral differences found between the different phases of locusts are not seen in phasmids. In addition, a few species can change their color physiologically in a matter of hours. This color change results from the aggregation or dispersion of pigment in the epidermal cells and is controlled by the endocrine system.

Though phasmids are generally uncommon, on occasion population densities of some species are sufficiently high that they become economically important defoliators in hardwood forests (e.g., eucalyptus in Australia [Key, 1991]). Associated with their rarity is the development, in many species, of facultative parthenogenesis, the unfertilized eggs giving rise only to females (very rarely to individuals of both sexes). In a few species, for example, Carausius (= Dixippus) morosus, parthenogenesis is virtually obligate, males being extremely rare. Eggs, which frequently resemble seeds, are laid singly and usually allowed to simply fall to the ground. Development time is variable, even among eggs laid by the same female. Eggs may remain viable for 2 or more years. Postembryonic development takes several months, and there are on average six molts in females, one or two fewer in males.

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.

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