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140 water through the use of such strategies as very rapid growth or burrowing into the substrate to avoid desiccation. Very rarely species have semiaquatic larvae or larvae that live in moist litter in rain forests. The majority of Odonata are warm-temperate or tropical species in which larval development is rapid so that one to several generations may be completed each year, with temperature and availability of food being the major determinants oflarval growth rate. In higher latitudes species may be univoltine (one generation per year), semivoltine (taking 2 years to complete development), or take up to 6 years to develop (the duration of development can vary within a species over its range). Typically, these Odonata overwinter in a temperature and/or photoperiodically controlled diapause in the larval stage, though some species pass the winter as eggs. Diapause, together with instar-specific temperature thresholds for development, ensures that adult emergence the following spring is highly synchronized, thus improving the chances of successful reproduction. Larvae pass through 10-15 instars. Late in the final stadium, the larval gills cease to function and the pharate adult crawls to the water surface to breathe air through the mesothoracic spiracles. Immediately prior to ecdysis, the pharate adult climbs out of the water on a suitable support; it then swallows air to split the exuvium and expand the abdomen and wings. In warmer regions many larger Anisoptera emerge at night, perhaps to avoid predation; elsewhere, emergence occurs through the day and is dependent on a threshold temperature being achieved.

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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