The Abiotic Environment

Because of the ameliorating effects of the water surrounding them, aquatic insects 657

are not normally exposed to the temperature extremes experienced by terrestrial species. Further, because ice is a good insulator, development may continue through the winter in some aquatic species in temperate climates, though air temperatures render development of terrestrial species impossible. Indeed, through evolution there has been a trend in some insects (e.g., species of Ephemeroptera and Plecoptera) to restrict their period of growth to the winter, passing the summer as eggs in diapause. Such species, whose developmental threshold is usually only slightly above 0°C, appear to gain at least two advantages from this arrangement. First, through the winter there is an abundance of food in the form of rotting vegetation, yet relatively little competition for it. Second, they are relatively safe from predators (fish) which are sluggish and feed only occasionally at these temperatures (Hynes, 1970b). Such a life cycle may also allow some species to inhabit temporary or still bodies of water that dry up or become anaerobic during summer.

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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