What is the origin of the universe? How did life appear on Earth and why was much of that life destroyed at various times in Earth's history? In this book four noted scientists--physicist Alan H. Guth, astronomer George Wetherill, biologist Lynn Margulis, and paeleobiologist David Raup-- propose answers to these questions, discussing the newest developments in some exciting areas of current research.

"Comprises four excellent essays. . . . The authors of this book seek to elucidate the remote, unusual events that most influenced the history of the cosmos and the earth. They describe...