Cradle of Life: The Discovery of Earth's Earliest FossilsOne of the greatest mysteries in reconstructing the history of life on Earth has been the apparent absence of fossils dating back more than 550 million years. We have long known that fossils of sophisticated marine life-forms existed at the dawn of the Cambrian Period, but until recently scientists had found no traces of Precambrian fossils. The quest to find such traces began in earnest in the mid-1960s and culminated in one dramatic moment in 1993 when William Schopf identified fossilized microorganisms three and a half billion years old. This startling find opened up a vast period of time--some eighty-five percent of Earth's history--to new research and new ideas about life's beginnings. In this book, William Schopf, a pioneer of modern paleobiology, tells for the first time the exciting and fascinating story of the origins and earliest evolution of life and how that story has been unearthed. Gracefully blending his personal story of discovery with the basics needed to understand the astonishing science he describes, Schopf has produced an introduction to paleobiology for the interested reader as well as a primer for beginning students in the field. He considers such questions as how did primitive bacteria, pond scum, evolve into the complex life-forms found at the beginning of the Cambrian Period? How do scientists identify ancient microbes and what do these tiny creatures tell us about the environment of the early Earth? (And, in a related chapter, Schopf discusses his role in the controversy that swirls around recent claims of fossils in the famed meteorite from Mars.) Like all great teachers, Schopf teaches the non-specialist enough about his subject along the way that we can easily follow his descriptions of the geology, biology, and chemistry behind these discoveries. Anyone interested in the intriguing questions of the origins of life on Earth and how those origins have been discovered will find this story the best place to start. |
Contents
Darwins Dilemma | 3 |
The Nature of Geologic Time | 4 |
The Schoolbook History of Life | 10 |
Darwins Dilemma | 13 |
Denouement | 34 |
Birth of a New Field of Science | 35 |
Famous Figures Enter the Field | 48 |
A Youngster Joins the Fray | 52 |
Earths First HighRise Condos | 178 |
Stromatolites of the Geologic Past | 189 |
What Are Stromatolites Good For? | 195 |
Cyanobacteria Earths Oldest Living Fossils | 208 |
The Status Quo Evolution of Cyanobacteria | 209 |
Evolutions Most Successful Ecologic Generalists | 225 |
Cells Like Ours Arise at Last | 230 |
Keys to Eukaryotic Success | 231 |
The Floodgates Open Full Bore | 61 |
The Oldest Fossils and What They Mean | 71 |
Questions and Answers about the Oldest Records of Life | 75 |
The Oldest Fossils Known | 93 |
How Did Life Begin? | 95 |
The Universals of Life | 101 |
How Did Mononers of CHON Arise on the Lifeless Earth? | 102 |
Organic Monomers beyond the Earth | 125 |
How Did Monomers Become Linked into Polymers? | 128 |
From Monomers to Polymers toward Life | 132 |
Metabolic Memories of the Earliest Cells | 133 |
The Essentials of Life | 137 |
Lifes Earliest Way to Make a Living | 144 |
A New Source of Glucose | 149 |
Why Do We Breathe Oxygen? | 152 |
The FourStage Development of Modern Metabolism | 155 |
So Far So Fast So Early? | 158 |
When Did Life Begin? | 160 |
How Did Evolution Proceed So Far So Fast So Early? | 162 |
Fossils Geology and Geochemistry | 163 |
Isotopic Evidence of Ancient Metabolisms | 167 |
Direct Evidence of Early Evolution | 175 |
Stromatolites Earths First HighRise Condos | 177 |
How Old Are the Eukaryotes? | 234 |
Eukaryotes Perfect the Art of Cloning | 237 |
A New Lifestyle Brings Major Change | 240 |
The Wax and Wane of Precambrian Acritarchs | 246 |
Prelude to the Phanerozoic | 253 |
Solution to Darwins Dilemma | 258 |
TakeHome Lessons | 263 |
EXTRAORDINARY CLAIMS EXTRAORDINARY EVIDENCE? | 273 |
Fossils Foibles and Frauds | 275 |
Man a Witness of the Deluge | 276 |
Beringers Lying Stones | 285 |
Theories on the Nature of Fossils | 293 |
Unearthing a Rosetta Stone | 297 |
The Hunt for Life on Mars | 298 |
NASA Stages a Press Conference | 300 |
Meteorites from Mars | 304 |
Search for the Smoking Gun | 307 |
Lessons from the Hunt | 318 |
Glossary | 321 |
Further Reading | 343 |
Index of Geologic Units and Genera and Species | 351 |
Subject Index | 355 |
Other editions - View all
Cradle of Life: The Discovery of Earth's Earliest Fossils J. William Schopf No preview available - 2001 |
Cradle of Life: The Discovery of Earth's Earliest Fossils J. William Schopf No preview available - 2001 |