Many people consider themselves environmentalist, and lots of children are busy with projects to save the Earth, but to be more effective it is firstly necessary that a clearer understand of the ecological principles is needed. This guide, to the essentials of ecology, aims to provide an introduction to the complexity of life on Earth. It contains the 60 basic ecological concepts which are explained, and it gives access to new thinking that scientists, environmentalists, politicians, government officials, business people and concerned citizens are using to seek a sustainable future. Also included are current findings on microscopic beings that made planet and animal life possible, and regulate global temperature and oxygen levels.