Based on nearly 40 years of teaching, this new edition of a bestselling text presents new findings that challenge conventional wisdom and considers their impact across species. It features new chapters on insect immunity, insect flight, insect vision, and diapause in insects, and includes updated and additional information on insect hormones and development. Providing a clear description of the principles, fundamentals, and terminology of insect physiology, this comprehensive resource offers an in-depth discussion of the relationship between insect physiology and animal behavior and ecology.