Robustness and Evolvability in Living Systems: (Princeton Studies in Complexity)

All living things are remarkably complex, yet their DNA is unstable, undergoing countless random mutations over generations. Despite this instability, most animals do not grow two heads or die, plants continue to thrive, and bacteria continue to divide. Robustness and Evolvability in Living Systems tackles this perplexing paradox. The book explores why genetic changes do not cause organisms to fail catastrophically and how evolution shapes organisms' robustness. Andreas Wagner looks at this problem from the ground up, starting with the alphabet of DNA, the genetic code, RNA, and protein molecules, moving on to genetic networks and embryonic development, and working his way up to whole organisms. He then develops an evolutionary explanation for robustness. 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.

Table of Contents:
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

About the Author :
Andreas Wagner is professor of biochemistry at the University of Zurich. He studies the evolution of biological systems on all levels of organismal organization, from genes and genomes to gene networks and embryonic development

Review :
"Wagner's treatise is more than good biology; it is also very interesting biology. The picture is painted by talented hands... If I have a favorite aspect of the book, it is the meticulous yet insightful analysis of neutral spaces and their relevance for the main themes of the book."--Eors Szathmary, Nature "Wagner contributes significantly to the emerging view that natural selection is just one, and maybe not even the most fundamental, source of biological order. His two-page epilogue throws out seven open questions for systems biologists and neo-Darwinians to consider; hopefully they will do so."--Greg Gibson, Science "This book is invaluable for everybody interested in robustness... I predict that for many years to come, Wagner's book will be the bibliographic reference work of choice for research on robustness."--Claus O. Wilke, BioScience "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."--Ethnology, Ecology, and Evolution