Wallace Arthur is Emeritus Professor of Zoology at the National University of Ireland, Galway. He is one of the founders of the interdisciplinary field of evolutionary developmental biology (evo-devo), and has a special interest in explaining scientific concepts in plain, nontechnical language. He is the author of nine previous books, including Biased Embryos and Evolution (Cambridge, 2004) and The Origin of Animal Body Plans (Cambridge, 1997).

• Preface; Acknowledgements; 1. What is an animal?; 2. Before there were animals; 3. How to make a fossil; 4. The Cambrian explosion; 5. How to make a species; 6. Jellyfish and their kin; 7. How to make a tree; 8. The enigmatic urbilaterian; 9. Animal symmetry and heads; 10. A plethora of worms; 11. Trends in animal complexity; 12. Where the octopus is king; 13. How to make an animal; 14. Exoskeletons galore; 15. Extinction; 16. Mouth first, mouth second; 17. Comparing embryos; 18. Larvae, mouthparts and moulting; 19. The animal toolkit; 20. Vertebrate origins and evolution; 21. From water to land to water; 22. Variation and inheritance; 23. Evolutionary novelties; 24. Human origins and evolution; 25. Animal plasticity; 26. The nature of adaptation; 27. The direction of evolution; 28. Animal extremophiles; 29. Extraterrestrial animals?; 30. The ghost in the machine; Appendix; References; Index.

'Wallace Arthur, a renowned evolutionary biologist, has written another of his excellent and easily approachable books introducing concepts, ideas and evidence of evolution. This new book is written in an informal style that a non-biologist should be able to follow without difficulty. He covers animal evolution from its beginning in deep time, and explains current ideas simply … Highly recommended for schools and biology students of all levels as well as the general reader.' Jennifer A. Clack, University Museum of Zoology, Cambridge

Wallace Arthur is Emeritus Professor of Zoology at the National University of Ireland, Galway. He is one of the founders of the interdisciplinary field of evolutionary developmental biology (evo-devo), and has a special interest in explaining scientific concepts in plain, nontechnical language. He is the author of nine previous books, including Biased Embryos and Evolution (Cambridge, 2004) and The Origin of Animal Body Plans (Cambridge, 1997).

• Preface; Acknowledgements; 1. What is an animal?; 2. Before there were animals; 3. How to make a fossil; 4. The Cambrian explosion; 5. How to make a species; 6. Jellyfish and their kin; 7. How to make a tree; 8. The enigmatic urbilaterian; 9. Animal symmetry and heads; 10. A plethora of worms; 11. Trends in animal complexity; 12. Where the octopus is king; 13. How to make an animal; 14. Exoskeletons galore; 15. Extinction; 16. Mouth first, mouth second; 17. Comparing embryos; 18. Larvae, mouthparts and moulting; 19. The animal toolkit; 20. Vertebrate origins and evolution; 21. From water to land to water; 22. Variation and inheritance; 23. Evolutionary novelties; 24. Human origins and evolution; 25. Animal plasticity; 26. The nature of adaptation; 27. The direction of evolution; 28. Animal extremophiles; 29. Extraterrestrial animals?; 30. The ghost in the machine; Appendix; References; Index.

'Wallace Arthur, a renowned evolutionary biologist, has written another of his excellent and easily approachable books introducing concepts, ideas and evidence of evolution. This new book is written in an informal style that a non-biologist should be able to follow without difficulty. He covers animal evolution from its beginning in deep time, and explains current ideas simply … Highly recommended for schools and biology students of all levels as well as the general reader.' Jennifer A. Clack, University Museum of Zoology, Cambridge

Wallace Arthur is Emeritus Professor of Zoology at the National University of Ireland, Galway. He is one of the founders of the interdisciplinary field of evolutionary developmental biology (evo-devo), and has a special interest in explaining scientific concepts in plain, nontechnical language. He is the author of nine previous books, including Biased Embryos and Evolution (Cambridge, 2004) and The Origin of Animal Body Plans (Cambridge, 1997).

• Preface; Acknowledgements; 1. What is an animal?; 2. Before there were animals; 3. How to make a fossil; 4. The Cambrian explosion; 5. How to make a species; 6. Jellyfish and their kin; 7. How to make a tree; 8. The enigmatic urbilaterian; 9. Animal symmetry and heads; 10. A plethora of worms; 11. Trends in animal complexity; 12. Where the octopus is king; 13. How to make an animal; 14. Exoskeletons galore; 15. Extinction; 16. Mouth first, mouth second; 17. Comparing embryos; 18. Larvae, mouthparts and moulting; 19. The animal toolkit; 20. Vertebrate origins and evolution; 21. From water to land to water; 22. Variation and inheritance; 23. Evolutionary novelties; 24. Human origins and evolution; 25. Animal plasticity; 26. The nature of adaptation; 27. The direction of evolution; 28. Animal extremophiles; 29. Extraterrestrial animals?; 30. The ghost in the machine; Appendix; References; Index.

'Wallace Arthur, a renowned evolutionary biologist, has written another of his excellent and easily approachable books introducing concepts, ideas and evidence of evolution. This new book is written in an informal style that a non-biologist should be able to follow without difficulty. He covers animal evolution from its beginning in deep time, and explains current ideas simply … Highly recommended for schools and biology students of all levels as well as the general reader.' Jennifer A. Clack, University Museum of Zoology, Cambridge