Prologue: A Vein Is a River: First sightings of the inner world ix
1. Nature's Criminals: How parasites came to be hated by just about everyone 1
2. Terra Incognita: Swimming through the heart, fighting to the death inside a caterpillar, and other parasitic adventures 23
3. The Thirty Years' War: How parasites provoke, manipulate, and get intimate with our immune system 55
4. A Precise Horror: How parasites turn their hosts into castrated slaves, drink blood, and manage to change the balance of nature 79
5. The Great Step Inward: Four billion years in the reign of Parasite Rex 118
6. Evolution from Within: The peacock's tail, the origin of species, and other battles against the rules of evolution 157
7. The Two-Legged Host: How Homo sapiens grew up with creatures inside 190
8. How to Live in a Parasitic World: A sick planet, and how the most newly arrived parasite can be part of a cure 216
Glossary 247
Notes 251
Further Reading and Selected Bibliography 265
Acknowledgments 287
Index 289