How do species interact with each other and their environment? What is biodiversity and can we afford to damage it? As our influence on the planet grows, answering these questions is becoming more pressing. Written in plain English, this book delivers short, pithy explanations of more than 90 key ideas. Step-by-step diagrams untangle tricky theories, illuminating quotes make the ideas and discoveries memorable, and witty illustrations enhance and play with our understanding of the science. You'll explore key theories, movements, and events in biology, geology, geography, and environmentalism, from the ideas of classical thinkers and Enlightenment attempts to impose order on nature, to discoveries such as DNA and theories like the Gaia hypothesis. Boxes highlighting "green" issues - the impact of pesticides, the plight of vulnerable species, and the search for renewable energy - appear throughout, as do profiles of influential figures - Charles Darwin, Carl Linnaeus, Rachel Carson, and James Lovelock - which place their ideas in their historical context. Whether you're new to ecology, a science student, or simply concerned about what's happening to our planet, this is a comprehensive introduction to the environment and climate change - arguably the most important subjects of our time.