Robustness & Evolvability in Living Systems (Princeton Studies in Complexity)

Wagner shows how evolution by natural selection preferentially finds and favors robust solutions to the problems organisms face in surviving and reproducing. Such robustness, he argues, also enhances the potential for future evolutionary innovation. Wagner also argues that robustness has less to do with organisms having plenty of spare parts (the redundancy theory that has been popular) and more to do with the reality that mutations can change organisms in ways that do not substantively affect their fitness.

Unparalleled in its field, this book offers the most detailed analysis available of all facets of robustness within organisms. It will appeal not only to biologists but also to engineers interested in the design of robust systems and to social scientists concerned with robustness in human communities and populations.

"This is a major contribution, addressing what are perhaps the central questions in the subject of complex adaptive systems: What makes systems robust and how does selection at different levels of organization act to shape robustness? It is a well-written, well-organized, provocative piece of scholarly work that will be widely read and debated."--Simon Levin, Princeton University

List of Figures ix

Acknowledgments xiii

Chapter 1: Introduction 1

PART I: ROBUSTNESS BELOW THE GENE LEVEL 13

Chapter 2: The Genetic Alphabet 15

Chapter 3: The Genetic Code 25

Chapter 4: RNA Structure 39

Chapter 5: Proteins and Point Mutations 62

Chapter 6: Proteins and Recombination 78

PART II: ROBUSTNESS ABOVE THE GENE LEVEL 91

Chapter 7: Regulatory DNA Regions and Their Reorganization in Evolution 93

Chapter 8: Metabolic Pathways 104

Chapter 9: Metabolic Networks 120

Chapter 10: Drosophila Segmentation and Other Gene Regulatory Networks 143

Chapter 11: Phenotypic Traits, Cryptic Variation, and Human Diseases 161

Chapter 12: The Many Ways of Building the Same Body 175

PART III: COMMON PRINCIPLES 193

Chapter 13: Neutral Spaces 195

Chapter 14: Evolvability and Neutral Mutations 217

Chapter 15: Redundancy of Parts or Distributed Robustness? 228

Chapter 16: Robustness as an Evolved Adaptation to Mutations 247

Chapter 17: Robustness as an Evolved Adaptation to Environmental Change and Noise 270

Chapter 18: Robustness and Fragility: Advantages to Variation and Trade-offs 281

PART IV: ROBUSTNESS BEYOND THE ORGANISM 295

Chapter 19: Robustness in Natural Systems and Self-Organization 297

Chapter 20: Robustness in Man-made Systems 310

Epilogue: Seven Open Questions for Systems Biology 321

Bibliography 323

Index 359