CONTENTS LIST OF CONTRIBUTORS PROLOGUE I. TOWARD THE ORIGINS OF LIFE A Definition of Life? Life on a Tape The Localization of Order The Chemistry of Life: Why Carbon? What Else? Water Suggestions for Further Reading II. THE ORIGINS OF LIFE: A BRIEF HISTORY OF THE SEARCH The Early Questioners The Evolutionary Synthesis The Experimental Era: Origins Enter the Laboratory The Space Age Suggestions for Further Reading III. THE TWO RECORDS: IN THE ROCKS AND IN THE CELLS The Age of the Earth Visible Traces in the Rocks The Carbon Chemistry of Ancient Rocks: An Opportunity The Record in Living Forms The Kingdoms of Life Suggestions for Further Reading IV. THE NATURAL EVIDENCE The Birth of the Solar System Comets and Meteorites Comparative Planetology Ancient Atmospheres The Ancient Surfaces Suggestions for Further Reading V. THE LABORATORY EXPERIENCE Introduction Extraterrestrial Evidence The Experimental Era Inorganic Aspects Polypeptides, Polynucleotides, and the Beginnings of Natural Selection Membranes Suggestions for Further Reading VI. RECOMMENDATIONS Introduction Solar System The Earth The Cell Chemical Evolution Models for Early Life Forms The Replication of Surface Patterns-An Alternative Entry for Life Summary Next Organizational Steps APPENDIX: MOLECULAR STRUCTURES OF IMPORTANT BIOLOGICAL COMPOUNDS