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 & 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 & 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 & 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 & 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 & 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 & the surprisingly long lives of bats & birds. Drawing on this grand evolutionary canvas Oxygen offers fresh perspectives on our own lives & deaths explaining modern killer diseases why we age & 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 & a humane synthesis of our place in nature. This remarkable book will redefine the way we think about the world.