Designed to give students a deep understanding of the central topics of introductory biology, E. O. Wilson’s Life on Earth is a captivating iBooks Textbook presented as a seven-unit collection. In this final unit, we explore the various biological communities that coexist on Earth. We look into how populations behave, interact, feed, and distribute themselves within ecosystems—and learn about how these environments are changing in the modern world. Each unit of the engagingly interactive E. O. Wilson’s Life on Earth features video, photo galleries, and Multi-Touch images and illustrations that inspire students to study, enjoy, and help protect the wonders of life on Earth.