The air we breathe is twenty-one percent oxygen, an amount higher than on any other known world. While we may take our air for granted, Earth was not always an oxygenated planet. How did it become this way? Oxygen is the most current account of the history of atmospheric oxygen on Earth. Donald Canfield--one of the world's leading authorities on geochemistry, earth history, and the early oceans--covers this vast history, emphasizing its relationship to the evolution of life and the evolving chemistry of the Earth. With an accessible and colorful first-person narrative, he draws from a variety of fields, including geology, paleontology, geochemistry, biochemistry, animal physiology, and microbiology, to explain why our oxygenated Earth became the ideal place for life.
Describing which processes, both biological and geological, act to control oxygen levels in the atmosphere, Canfield traces the records of oxygen concentrations through time. Readers learn about the great oxidation event, the tipping point 2.3 billion years ago when the oxygen content of the Earth increased dramatically, and Canfield examines how oxygenation created a favorable environment for the evolution of large animals. He guides readers through the various lines of scientific evidence, considers some of the wrong turns and dead ends along the way, and highlights the scientists and researchers who have made key discoveries in the field.
Showing how Earth's atmosphere developed over time, Oxygen takes readers on a remarkable journey through the history of the oxygenation of our planet.
Donald E. Canfield is professor of ecology at the University of Southern Denmark and director of the Nordic Center for Earth Evolution (NordCEE). He is a member of the National Academy of Science, coauthor of Aquatic Geomicrobiology and coeditor of Fundamentals of Geobiology.
"His excellent descriptions of the scientific process show how competing hypotheses, and the scientists who present them, vie for supremacy. Canfield also offers a philosophical perspective: scientific understanding provides true insight into the structure of the natural world."--Publishers Weekly
"With humor and humanity, Oxygen captures the excitement of scientific discovery and describes the amazing natural history of how Earth's oxygenated atmosphere came to be."--Ed DeLong, Massachusetts Institute of Technology
"A fascinating, accessible tour through the history of atmospheric oxygen, written by one of the world's top geobiologists. Canfield takes the reader from the anaerobic early Archean Earth up through the modern highly oxygenated environment, providing pointers to the relevant scientific literature along the way. Even experts in this field will learn things from his book."--James Kasting, author of How to Find a Habitable Planet
"In Oxygen, Don Canfield recounts two epics in one--the evolution of breathable air over the entirety of Earth history, and the equally engaging account of how scientists have reconstructed this history from chemical details in ancient rocks. Even those who know the story well, or think they do, will find much food for thought."--Andrew Knoll, Harvard University, author of Life on a Young Planet: The First Three Billion Years of Evolution on Earth
"Canfield takes us on a journey through the discovery of what produces oxygen, how oxygen evolved on the planet, and how that evolution influenced other aspects of planetary evolution. An enjoyable book."--Lee Kump, coauthor of The Earth System
Table of Contents:
Chapter 1. What Is It about Planet Earth? 1
Chapter 2. Life before Oxygen 13
Chapter 3. Evolution of Oxygenic Photosynthesis 26
Chapter 4. Cyanobacteria: The Great Liberators 41
Chapter 5. What Controls Atmospheric Oxygen Concentrations? 56
Chapter 6. The Early History of Atmospheric Oxygen: Biological Evidence 72
Chapter 7. The Early History of Atmospheric Oxygen: Geological Evidence 85
Chapter 8. The Great Oxidation 98
Chapter 9. Earth's Middle Ages: What Came after the GOE 110
Chapter 10. Neoproterozoic Oxygen and the Rise of Animals 123
Chapter 11. Phanerozoic Oxygen 138
Chapter 12. Epilogue 153