Chapter 32: Introduction to Animal Evolution Chapter 33: Invertebrates

1. Overview of Animal Phylogeny part 1: invertebrates Chapter 32: Introduction to Animal Evolution Chapter 33: Invertebrates

2. Invertebrates: orientation to topics

3. Figure 33.1 Review of animal phylogeny

4. Table 25-1a

5. The Situation in the Late Precambrian Precambrian origin of integrated organisms and basic body plans Parazoa (Porifera) sponges Radiata (Cnidaria) sea anemones and sea pens Bilateralia Protostomes primitive molluscs unidentified worms Dickinsonia costata - annelid? Charnia masoni - a sea pen

6. Fossils from the End of the Precambrian…

7. colonial choanoflagellate Figure 32.8 Animal phylogeny based on sequencing of SSU-rRNA

8. Figure 33.2 Sponges

9. Figure 33.3 Anatomy of a sponge Sponges have specialized cells, But they lack true tissues, groups of similar cells that act as a functional unit and are Isolated from other tissues by Membranous layers.

10. Figure 32.8 Animal phylogeny based on sequencing of SSU-rRNA

11. Figure 33.6 Cnidarians: Hydrozoans (top left), jelly (top right), sea anemone (bottom left), coral polyps (bottom right)

12. Figure 33.5 A cnidocyte of a hydra

13. Figure 33.4bx Jelly medusa

14. Figure 33.4 Polyp and medusa forms of cnidarians

15. A cnidarian life cycle

16. Figure 26.8 The Cambrian radiation of animals D R D PL P 525 PL PL Burgess Shale PE (Ediacaran)

17. Figure 32.13x Burgess Shale fossils

18. Figure 32.13 A sample of some of the animals that evolved during the Cambrian explosion

19. Porifera and Cnidaria are prominent in the Burgess Shale Annelid worms in the Burgess shale

20. Anomalocaris hunts so are arthropods!!

21. Fossils of recognizable phyla in the Burgess shale

22. Mystery animals in the Burgess shale Dinomischus Wiwaxia corrugata

23. Causes of the radiation: Predator-prey relationships originate. Atmospheric oxygen reaches sufficient levels. Homeobox genes evolve. Figure 26.8 The Cambrian radiation of animals D R D PL P 525 PL PL Burgess Shale PE (Ediacaran)

24. Figure 32.8 Animal phylogeny based on sequencing of SSU-rRNA

25. Figure 33.1 Review of animal phylogeny

26. Figure 32.8 Animal phylogeny based on sequencing of SSU-rRNA trochophore lophophore

27. Prominent Phyla of Lophotrochozoans

28. Figure 33.14 Lophophorates: Bryozoan (left), brachiopod (right) LOPHOPHORE

29. The fate of the brachiopods Brachiopods Bivalves millions of years ago

31. Figure 32.8 Animal phylogeny based on sequencing of SSU-rRNA trochophore lophophore

32. Figure 32.6 Body plans of the bilateria

33. Figure 33.22 Cephalopods: Squid (top left and bottom left), nautilus (top right), octopus (bottom right)

34. Figure 33.17 A chiton

35. Figure 33.21 Anatomy of a clam Molluscs are coelomate, lophotrochozoan protostomes with a foot and a mantle

36. Ammonites - extinct since the Cretaceous, along with dinosaurs

37. Lophotrochozoans, a clade identified by molecular data, have the widest range of body forms.

38. Figure 32.8 Animal phylogeny based on sequencing of SSU-rRNA lophophore

39. Nematodes – ecdysozoans with priminent medical significance hookworms Trichinella – the nematode that causes trichinosis

40. CRUSTACEANS as examples of ARTHROPODA

41. Figure 33.28 Horseshoe crabs, Limulus polyphemus

42. Figure 33.27 A trilobite fossil

43. Figure 33.x1 Insecta: beetle

44. Figure 32.8 Animal phylogeny based on sequencing of SSU-rRNA

45. Figure 32.7 A comparison of early development in protostomes and deuterostomes

46. Figure 33.37 Echinoderms: Sea star (top left), brittle star (top right), sea urchin (bottom left), sea lily (bottom right),

47. fossil crinoids