Oxygen - Nick Lane

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Résumé :
Oxygen has had extraordinary effects on life. Three hundred million years ago, in Carboniferous times, dragonflies grew as big as seagulls, with wingspans of nearly a metre. Researchers claim they could have flown only if the air had contained more oxygen than today - probably as much as 35 per cent. Giant spiders, tree-ferns, marine rock formations and fossil charcoals all tell the same story. High oxygen levels may also explain the global firestorm that contributed to the demise of the dinosaurs after the asteroid impact. The strange and profound effects that oxygen has had on the evolution of life pose a riddle, which this book sets out to answer. Oxygen is a toxic gas. Divers breathing pure oxygen at depth suffer from convulsions and lung injury. Fruit flies raised at twice normal atmospheric levels of oxygen live half as long as their siblings. Reactive forms of oxygen, known as free radicals, are thought to cause ageing in people. Yet if atmospheric oxygen reached 35 per cent in the Carboniferous, why did it promote exuberant growth, instead of rapid ageing and death? Oxygen takes the reader on an enthralling journey, as gripping as a thriller, as it unravels the unexpected ways in which oxygen spurred the evolution of life and death. The book explains far more than the size of ancient insects: it shows how oxygen underpins the origin of biological complexity, the birth of photosynthesis, the sudden evolution of animals, the need for two sexes, the accelerated ageing of cloned animals like Dolly the sheep, and the surprisingly long lives of bats and birds. Drawing on this grand evolutionary canvas, Oxygen offers fresh perspectives on our own lives and deaths, explaining modern killer diseases, why we age, and what we can do about it. Advancing revelatory new ideas, following chains of evidence, the book ranges through many disciplines, from environmental sciences to molecular medicine. The result is a captivating vision of contemporary science and a humane synthesis of our place in nature. This remarkable book might just redefine the way we think about the world. Oxford Landmark Science books are 'must-read' classics of modern science writing which have crystallized big ideas, and shaped the way we think....

Biographie:
Dr Nick Lane is a British biochemist and writer. He was awarded the first Provost's Venture Research Prize in the Department of Genetics, Evolution, and Environment at University College London, where he is now a Reader in Evolutionary Biochemistry. Dr Lane's research deals with evolutionary biochemistry and bioenergetics, focusing on the origin of life and the evolution of complex cells. Dr Lane was a founding member of the UCL Consortium for Mitochondrial Research, and is leading the UCL Research Frontiers Origins of Life programme. He was awarded the 2011 BMC Research Award for Genetics, Genomics, Bioinformatics and Evolution, and the 2015 Biochemical Society Award for his sustained and diverse contribution to the molecular life sciences and the public understanding of science. His books include Oxygen: The Molecule that Made the World (OUP, 2002), and Power, Sex, Suicide: Mitochondria and the Meaning of Life (OUP, 2005)....

Sommaire:

• 1: Introduction: Elixir of Life - and Death
• 2: In the Beginning: The Origins and Importance of Oxygen
• 3: Silence of the Aeons: Three Billion Years of Microbial Evolution
• 4: Fuse to the Cambrian Explosion: Snowball Earth, Environmental Change and the First Animals
• 5: The Bolsover Dragonfly: Oxygen and the Rise of the Giants
• 6: Treachery in the Air: Oxygen Poisoning and X-Irradiation: A Mechanism in Common
• 7: Green Planet: Radiation and the Beginnings of Photosynthesis
• 8: Looking for LUCA: Last Ancestor in the Age Before Oxygen
• 9: Portrait of a Paradox: Vitamin C and the Many Faces of an Antioxidant
• 10: The Antioxidant Machine: A Hundred and One Ways of Living with Oxygen
• 11: Sex and the Art of Bodily Maintenance: Trade-offs in the Evolution of Ageing
• 12: Eat! Or You'll Live Forever: The Triangle of Food, Sex, and Longevity
• 13: Gender Bender: The Rate of Living and the Need for Sexes
• 14: Beyond Genes and Destiny: The Double Agent Theory of Ageing and Disease
• 15: Life, Death and Oxygen: Lessons From Evolution on the Future of Ageing
• Further Reading
• Glossary
• Index