Systematics may be defined as the study of the kinds and diversity of organisms and the relationships among them. Taxonomy, the theory and practice of identifying, describing, naming, and classifying organisms, is an integral part of systematics. Classification is the arrangement of organisms into groups (taxa, singular taxon) on the basis of their relationships. It follows that identification can take place only after a classification has been established. It should be emphasized that not all authors adopt these definitions. Taxonomy is often used as a synonym of systematics (as defined above), while classification is sometimes used rather loosely (and incorrectly) as a synonym of identification.

Systematics is an activity that impinges on most other areas ofbiological endeavor. Yet, its importance (and fiscal support for it) seem to have diminished in recent years. To some extent, this may be the fault of systematists who tend to work in isolation, often focusing on some small and obscure group of organisms. This may be especially true of entomological systematists who, faced with the enormous diversity of the Insecta, tend to be seen as "counters of bristles," "measurers of head width" and performers of other activities of little relevance to the outside world. In fact, as Danks (1988) elegantly pointed out, nothing could be further from the truth. Systematics has played, and continues to play, a major role in fundamental evolutionary and ecological studies, for example faunistic surveys, zoogeographic work, life-history investigations and studies of associations between insects and other organisms. In applied entomology good systematic work is the basis for decisions on the management of pests. Indeed, Danks (1988) provided examples of pest-management projects in which inadequate or faulty systematics resulted in failure, sometimes with great economic and social cost (and see Section 2).

The taxonomy of insects, like that of most other groups of living organisms, continues to be based primarily on external structure, though limited use has also been made (sometimes of necessity, especially between species) of physiological, developmental, behavioral, and cytogenetic data. Molecular biological analyses of problems in insect systematics have increased exponentially over the past two decades (Caterino et al., 2000). These analyses, principally using mtDNA sequences, have principally focused on the resolution of relationships at lower taxonomic levels, for example, among subspecies, species and species groups. Molecular phylogenetic studies of higher insect taxa (e.g., relationships among

92 orders), though far fewer, have nevertheless generated important, sometimes even contro versial, conclusions (see Chapter 2 for examples).

The purpose of this chapter is to provide a short introduction to the systematics of insects, including some of the technical terms applied by workers in these fields, as a basis for Chapters 5-10 inclusive, which deal with individual insect orders.

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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