The Biotic Environment

FIGURE 23.2. An example of a food web in a freshwater ecosystem, showing the importance of insects. [From P. W. Price, The concept of the ecosystem, in: Ecological Entomology (C. B. Huffaker and R. L. Rabb, eds.). Copyright © 1984 by John Wiley and Sons, Inc. Reprinted by permission of John Wiley and Sons, Inc.]

within a small area so that it is available to relatively few insects. As an interesting example of this Andrewartha (1961) cited the Shinyanga Game-Extermination Experiment in East Africa in which, over the course of about 5 years, the natural hosts of tsetse flies were virtually exterminated over an area of about 800 square miles. At the end of this period one small elephant herd and various small ungulates remained in the game reserve. However, almost no tsetse flies could be found, despite the fact that, collectively, the mammals that remained could supply enough blood to feed the entire original population of flies. The distribution of the food was now so sparse that the chance of flies obtaining a meal was practically nil. (2) The food may be randomly distributed but difficult to locate. Thus, only a fraction of the individuals searching ever find food. Such is probably the situation in many parasitic or hyperparasitic species whose host is buried within the tissues of plants or other

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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