Life on a Young Planet

Acknowledgments ix Prologue 1 Chapter 1. In the Beginning? 6 Chapter 2. The Tree of Life 16 Chapter 3. Life's Signature in Ancient Rocks 32 Chapter 4. The Earliest Glimmers of Life 50 Chapter 5. The Emergence of Life 72 Chapter 6. The Oxygen Revolution 89 Chapter 7. The Cyanobacteria, Life's Microbial Heroes 108 Chapter 8. The Origins of Eukaryotic Cells 122 Chapter 9. Fossils of Early Eukaryotes 139 Chapter 10. Animals Take the Stage 161 Chapter 11. Cambrian Redux 179 Chapter 12. Dynamic Earth, Permissive Ecology 206 Chapter 13. Paleontology ad Astra 225 Epilogue 243 Further Reading 247 Index 269

Andrew H. Knoll is Fisher Professor of Natural History at Harvard University and a Member of the National Academy of Sciences. A paleontologist by training, he has spent more than two decades working to integrate geological and biological perspectives on early life.

Winner of the 2003 Book Award in Science, Phi Beta Kappa "In a book so well written that nonspecialists and specialists alike will find much to savor, [Knoll] captures both the excitement of scientific discovery and the intricacies of scientific interpretation... Readers interested in substance will certainly not be disappointed."--Publishers Weekly "Knoll is well placed to tell this amazing story, and he does so with verve."--Douglas Palmer, New Scientist "Andrew Knoll is an ideal guide through this early phase of life's history on the Earth... [O]ne of the strengths of Knoll's book is that it presents science as the open-ended endeavor that it is... Life on a Young Planet . .. expresses better than most the bumptious vitality and sheer fun of open-minded research."--Stefan Bengtson, Nature "A fascinating book... The catastrophic surface narrative of this impressive and intriguing book would surely have pleased Stephen Jay Gould; but I think its deterministic subtext would have pleased Charles Darwin still more."--Matt Cartmill, Times Literary Supplement "Life on a Young Planet stands apart from it predecessors in two fundamental respects. First, Knoll is perhaps the most qualified person to write such an epic: a renaissance man whose text is filled with insightful quotes from authors ranging from Darwin to Dickins to Dyson... Second ... this book describes the coevolution of life on Earth as an integrated biochemical system that has profoundly and irrevocably changed over time."--Guy M. Narbonne, Science "A balanced, excellent account of current theories and discussions of the origin and early evolution of life... Knoll is able to convey difficult scientific issues with a minimum of jargon, using a brisk and witty prose... He is a gifted storyteller with a knack for choosing the right anecdote... A browse through Knoll's book will enlighten both the cognoscenti and those unfamiliar with the complexities of reading a fossil record... Knoll manages to present a