The echidna is one of the world's most extraordinary creatures, a living fossil whose relatives were walking the earth over 100 million years ago. Like the platypus, it is a mammal that lays eggs. And like all mammals, it has fur and produces milk. This book describes the echidna's lifestyle and the adaptations that have made it so successful. It draws on the latest research into these strange creatures, covering their evolution, anatomy, senses, reproduction, behaviour, feeding habits and metabolism. The authors reveal fascinating new findings, showing how echidnas are masters of their environment, and not simply some sort of mammal 'test model' that went wrong. A final chapter on conservation includes information on captive diet and management.