194 example, Schistocerca gregaria gregaria (the desert locust of Africa and southwest Asia),

S. americana (the South American locust, comprising at least two major subspecies), and Nomadacris septemfasciata (the red locust). The OEDIPODINAE are another subfamily of worldwide distribution, but whose members are found mainly in warmer, drier areas. It contains many important pest species, including Locusta migratoria (the migratory locust of Africa, northern Australia, Asia, and southern Europe, with several distinct subspecies) and Chortoicetes terminifera (the Australian plague locust). The CATANTOPINAE constitute another large, widely distributed subfamily. As presently constituted, it is a rather heterogeneous assemblage and is in gradual process of revision. Usually included in this subfamily are the genera Melanoplus and Dichropus, several species of which are major pests, particularly in the grassland areas of North and South America, respectively.

The term "locust" is applied to about 20 species of Acrididae that are capable, under certain conditions, of aggregating in immense swarms that may migrate for considerable distances and cause massive damage to vegetation. Locusts (and also some Tettigonioidea, Phasmida, and Lepidoptera) can exist in more than one form or "phase." These phases differ not only in color and morphology, but also in their physiology, ecology, and behavior. Phase polymorphism is largely a density-dependent phenomenon. Under extended conditions of low population density, the locusts exist in the "solitary phase." If conditions change so that the population density increases, the locusts enter a "transition phase," and under high density conditions change to the "gregarious phase." It is the latter phase that is of importance with reference to swarming. Gregarious larvae (hoppers) are highly active and "march" in vast groups from place to place. As adults they may be carried for very considerable distances by wind currents (see Chapter 22, Section 5.2). New swarms in most species originate in more or less permanent breeding areas (outbreak areas), though desert locusts seem to be more strictly nomadic, even in the solitary phase. Though adults may breed in the regions to which they are distributed for a period of several years, the population gradually decreases because of unsuitable conditions. The effects of population density on phase development are mediated via the endocrine system (see Chapter 21, Section 7).

The PAMPHAGIDAE includes about 320 species of acridoids found in the palearctic region, south-west Asia, and Africa. Commonly known as toad grasshoppers on account of their rough, sometimes spiny appearance, they are highly camouflaged, mimicking foliage, stones, dead branches, etc. They typically occur in dry, semi-desert environments.

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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