This chapter has hopefully provided a bit more insight into the disciplinary core idea (DCI) of Evolution: Unity and Diversity. Taking an evolutionary perspective on biology is one of the most powerful ways that scientists make sense of and reason about organisms in the natural world. The evolutionary perspective allows us to understand why living things are the way they are and, importantly, it allows the scientific community to continue to wonder and ask questions about the natural world and our place within it. A list of materials, teacher background information, assessment, standards, safety, and references are provided. This book selection also includes the Table of Contents, Foreword, Acknowledgments, About the Editors, Contributors, Appendix, Image credits, and Index.