The origin of cells remains one of the most fundamental problems in biology, one that over the past two decades has spawned a large body of research and debate. With In Search of Cell History, Franklin M. Harold offers a comprehensive, impartial take on that research and the controversies that keep the field in turmoil. Written in accessible language and complemented by a glossary for easy reference, this book investigates the full scope of cellular history. Assuming only a basic knowledge of cell biology, Harold examines such pivotal subjects as the relationship between cells and genes; the central role of bioenergetics in the origin of life; the status of the universal tree of life with its three stems and viral outliers; and the controversies surrounding the last universal common ancestor. He also delves deeply into the evolution of cellular organization, the origin of complex cells, and the incorporation of symbiotic organelles, and considers the fossil evidence for the earliest life on earth. In Search of Cell History shows us just how far we have come in understanding cell evolution—and the evolution of life in general—and how far we still have to go.