The

PLECOPTEROID, BLATTOID, AND ORTHOPTEROID ORDERS

FIGURE 7.8. Mature nest of Bellicositermes natalensis (Termitidae). [After P.-P. Grassé (ed.), 1949, Traité de Zoologie, Vol. IX. By permission of Masson, Paris.]

buffers against sudden changes in external temperature. In cold weather, termites behave much like bees, clustering together in the center of the nest and effectively reducing the "operating space," whose temperature must be maintained by metabolic heat. In mound-building termites, whose nest may be fully exposed to the sun, the temperature in the center of the nest is held steady as a result of the excellent insulation provided by either thick walls or thin, cavity-bearing walls in which food is stored. However, as the degree of insulation from external temperature fluctuations increases, so does the problem of gas exchange. Although it has been shown experimentally that termites can withstand very high carbon dioxide concentrations, field studies have indicated that under natural conditions they do not face this problem because of the nest's air-conditioning system. Convection currents, created by the different temperatures at the center and periphery of the nest, are the basis of the system. In Bellicositermes natalensis the heat created in the central (nursery) area causes the air in this region to rise to the upper chamber (Figure 7.8). The air then moves along the radial ducts to the peripheral region of the nest, which comprises a system of thin-walled tubes. Carbon dioxide and oxygen can diffuse easily across these walls. As the "fresh" air in the peripheral tubes cools, it sinks into the "cellar" of the nest, eventually to be drawn by convection back into the central area.

Termites are primitively wood-eating insects, and this habit is retained in most lower termites and many of the higher forms. Others feed on dry grass, fungi, leaves, humus, rich soil, and herbivore dung. In most species food is consumed at its source, individuals remaining in the nest being fed by trophallaxis (see below). However, some termites travel considerable distances (e.g., 100 m or more in Mastotermes) from the nest to a food source.

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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