Life History and Habits

Most species are active, diurnal (most Caelifera), or nocturnal (many Ensifera) insects, capable of jumping in order to escape from would-be predators, or to launch themselves into flight. Flying ability is mostly rather limited, but a number of species (mostly members of the Acrididae) are capable of sustained flight for many hours. Members of a few groups are typically cryptozoic, living in humus or beneath logs and stones. A few species are true soil dwellers and some live in caves. Although normally "solitary," members of a number of species (especially of Caelifera) may become gregarious under certain conditions to form swarms that may reach enormous proportions (Superfamily Acridoidea). Most Orthoptera are phytophagous and consequently are extremely important because of the damage they may do to crops. Many species of Ensifera are omnivorous and a few are carnivorous, feeding on other insects, which in some instances they catch with their specialized forelegs.

Stridulation occurs in a large number of Orthoptera and serves to bring sexes together and to elicit certain behavioral responses leading to copulation. Stridulation is achieved in a great variety of ways, but, in most species, the principal method of sound production is either tegminal (crickets and katydids) or femoroalary (in many grasshoppers). In the former, the sound is typically produced when one tegmen is drawn across the other. The especially strengthened, toothed cubital vein (file) on one tegmen makes contact with the raised edge (scraper) of the other tegmen, and an adjacent area of wing, the mirror, is caused to resonate. In femoroalary stridulation it is normally the drawing of the hind femora across the tegmina that creates the sound. Another common method of stridulation, particularly among more primitive forms, is femoroabdominal, whereby the inside of the femur is rubbed over teeth or ridges on the side of the abdomen. Some grasshoppers make a clattering sound in flight either by striking the hind wing on the tegmen or by the rapid opening and closing of the fanlike hind wings. And there are numerous other less common means of sound production (Otte, 1977). It is generally the male that stridulates, though in some species the female also may perform this act. Stridulation is almost always species-specific, that is, each species has its own song, and this probably serves as an isolating mechanism between closely related species. Exceptions to this rule may sometimes occur, however, if there are other isolating mechanisms. For example, the songs of Gryllus pennsylvanicus and G. veletis are almost identical, but the former occurs as adults only in late summer and autumn and the latter in late spring and early summer.

Reproduction is almost always sexual, though a few facultatively parthenogenetic species are known. Sperm are transferred in spermatophores (except in some Eumastacidae) that vary widely in size and complexity. In many Ensifera the spermatophore is large and, after sperm evacuation, is eaten by the female, thereby making an important nutritive contribution to egg development (Gwynne, 2001). In Caelifera one to many small spermatophores may be transferred during each copulation. Eggs are laid singly or in small groups (in many Ensifera) or in batches (in Caelifera) in a variety of locations. The Ensifera typically lay them in or on stems or leaves, or in loose soil or humus. The Caelifera mostly dig into the soil, making alternate opening and closing movements of the ovipositor, and typically deposit the eggs in a mass of frothy material. This soon hardens to form a cylindrical mass known as the egg pod. Usually several batches of eggs are laid. The duration of embryonic development is varied, and many temperate species pass the winter in a diapausing egg stage, though some overwinter as juveniles. The pronymph (first-instar larva) is covered with a loose cuticle that serves to protect the insect as it emerges from the substrate. This cuticle is shed usually within a few minutes of hatching. In most species there are four to six additional larval instars in which the young form increasingly resembles the adult.

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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