Life History and Habits

Most adult Hymenoptera feed on nectar or honeydew and thus are found on or near flowers. A few are predaceous, while others feed on plant tissue or fungi. Through their search for nectar and pollen for feeding the larvae, the social Hymenoptera play an extremely important role in the cross-pollination of flowering plants. In addition, some parasitoid and predatory forms are important agents in the control of insects that could otherwise become pests. For these reasons the Hymenoptera are considered to be the insect order of greatest benefit to humans.

In the complexity of its members' behavior the Hymenoptera surpass all other insect orders. The development of this behavior has accompanied the evolution of parental care and, ultimately, social life in the order. Within the order the importance of the male sex shows a gradual diminution, and facultative or cyclic diploid parthenogenesis (Chapter 20, Section 8.1) becomes the rule rather than the exception in some groups of social Hymenoptera. The majority of individuals produced are females, which, however, do not mature sexually but merely serve the colony as a whole. Males are produced only for the purpose of founding new colonies; they develop from unfertilized eggs and thus are haploid.

Four broad categories of life history can be recognized in Hymenoptera, and these are paralleled by an increasing complexity of behavior patterns exhibited by females. These life histories are based on the feeding habits of the larvae. The simplest life history is found in Symphyta, whose larvae are generally foliage eaters or wood borers, and females simply deposit their eggs on a host plant. The second stage is seen in the primitive Apocrita, whose larvae are parasitoids, that is, they feed on the tissues of a host that they eventually kill. This necessitated the evolution, in females, of the ability to search out a suitable (sometimes highly specific) host on which to oviposit. In more advanced Apocrita such as the solitary wasps and bees, the beginning of parental care is seen. A female builds a special cell in which to deposit an egg. She then uses either mass provisioning, that is, the supplying of sufficient food at one time for the whole of larval development, or progressive provisioning in which food is supplied at intervals throughout larval life. Associated with this development is the evolution of the ovipositor as a sting, for paralyzing, though not killing, prey. Thus, the stage has been reached where a female comes into contact with her progeny. The fourth type of life history is found in the social Hymenoptera where a larva is fed throughout its development on food provided by the parent or another adult (which is usually sterile). The food is animal material (in wasps), or plant material such as pollen and nectar (bees), or seed, tissues, or fungi (ants). In primitive social species mass provisioning is used. At a more advanced stage progressive provisioning occurs, and there may be several egg-producing females in the colony. Gradually, division of labor evolves, and the colony then contains a single egg-laying female, the queen, and large numbers of structurally distinguishable females, the workers, which perform various duties in the colony. In some species there is a temporal separation of these duties, that is, an individual performs different duties at different ages.

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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