This book is part of the Cambridge Modular Sciences series for A and AS level. It aims to develop an understanding of: ecology and the complex interactions occurring in an ecosystem, the importance of practical investigation in the ecology of plant and animal communities, the fact that conservation can occur at local, national and international levels, different interest groups and their objectives when setting up a conservation programme. To help the student, learning objectives are listed at the start of each chapter and self-assessment questions are scattered throughout the text. Answers to these are provided at the back of the book. Each chapter concludes with a summary and longer questions.