Introduction

Overview of ecology, and chapter structure

Scientific progress is not reliant simply on the collection of facts. Even the entomological research conducted to support pest management practice is influenced in one way or another by underlying theory (Chapters 2 and 3). Sometimes that theory is recognisable only by searching out the unstated assumptions that underpin gathering and interpretation of the data. All the underlying theoretical structures that influence research on pests and beneficials therefore need to be located, scrutinised for the validity of their underlying assumptions, and examined for their practical contribution to IPM (Chapter 2). That a strong theoretical basis for IPM research is needed is perhaps best underscored by our persistent inability to understand the ecology of so many major pests, despite decades of research effort (much of it of a fact-gathering nature), and the low rates of IPM success achieved so far (Chapter 3).