Ill 



TABLE OF CONTENTS 



Page 



LIST OF CONTRIBUTORS v 



PROLOGUE vii 



I. TOWARD THE ORIGINS OF LIFE 1 



A Definition of Life? 1 



Life on a Tape 3 



The Localization of Order 5 



The Chemistry of Life: Why Carbon? What Else? 7 



Water 9 



Suggestions for Further Reading 11 



II. THE ORIGINS OF LIFE: A BRIEF HISTORY 



OF THE SEARCH 13 



The Early Questioners . . 13 



The Evolutionary Synthesis 16 



The Experimental Era: Origins Enter the Laboratory .... 17 



The Space Age 18 



Suggestions for Further Reading 21 



III. THE TWO RECORDS: IN THE ROCKS AND 



IN THE CELLS 23 



The Age of the Earth 25 



Visible Traces in the Rocks 26 



The Carbon Chemistry of Ancient Rocks: 



An Opportunity 30 



The Record in Living Forms 33 



The Kingdoms of Life 34 



Suggestions for Further Reading 40 



IV. THE NATURAL EVIDENCE 43 



The Birth of the Solar System 43 



Comets and Meteorites 47 



Comparative Planetology 55 



