This book introduces what is essential and exciting in evolutionary biology to university students in a book that can be read straight through, one chapter per session, in one semester. Care has been taken to express complex ideas in simple language. Concepts and examples are featured prominently. What is important is emphasised and what is not important is left out, making this a more focused and concise introduction than the main competitors. Running summaries in the margins help the reader find their way around and enliven the reading experience. To further aid navigation there are summaries at chapter ends and each chapter begins and ends with connections to the neighbouring chapters.