Content:

1. Science of Zoology and Evolution of Animal Diversity 1
2. Animal Ecology 35
3. Animal Architecture 55
4. Taxonomy and Phylogeny of Animals 72
5. Protozoan Groups 89
6. Sponges: Phylum Porifera 112
7. Radiate Animals: Cnidarians and Ctenophores 123
8. Acoelomate Bilateral Animals: Flatworms, Ribbon Worms, and Mesozoans 147
9. Gnathiferans and Smaller Lophotrochozoans 164
10. Molluscs 178
11. Annelids and Allied Taxa 204
12. Smaller Ecdysozoans 222
13. Arthropods 235
14. Chaetognaths, Echinoderms, and Hemichordates 279
15. Vertebrate Beginnings 300
16. Fishes 317
17. The Early Tetrapods and Modern Amphibians 341
18. Amniote Origins and Nonavian Reptiles 356
19. Birds 375
20. Mammals 399