Explores the complex and delicate societies and relationships that allow all ecosystems to run smoothly.

Includes glossary. Includes index and glossary.

Interaction with the environment -- Ecosystems - staying alive -- Sunlight and photosynthesis -- Food chains, food webs, and energy pyramids -- Biomagnification -- Alien invaders! -- Symbiosis -- Filling a niche -- Competition -- Roaming raccoons -- Ecological succession -- Extinction : gone forever -- Pollution : you can help -- Field study -- Quiz.