1. Section 1 Introduction to Vertebrates
Chapter 39 Fishes
Section 1
Introduction to Vertebrates

2. Characteristics Phylum Chordata Subphylum Vertebrata
Notochord, pharyngeal pouches, dorsal nerve cord, postanal tail
Vertebrae- spine
Cranium- skull that protects brain
Endoskeleton (bone or cartilage)

3. Vertebrate Classes Class Myxini- hagfish (jawless)
Class Cephalaspidomorphi- lamprey (jawless)

4. Vertebrate Classes
Class Chondrichthyes- sharks, rays, skates, & ratfishes

5. Vertebrate Classes
Class Actinopterygii (ray-finned fish)

6. Vertebrate Classes Class Sarcopterygii (lobe-finned fishes) Lung Fish
Coelacanth

7. Vertebrate Classes
Class Amphibia (amphibians- frogs, toads, salamanders)

8. Vertebrate Classes
Class Reptilia (reptiles- turtles, crocodiles, alligators, lizards, & snakes)

9. Vertebrate Classes
Class Aves (birds)

10. Vertebrate Classes
Class Mammalia (mammals)

11. Vertebrate Evolution
450 million years ago, the first fishes with jaws and paired fins appeared
Jaws are thought to have evolved from the first pair of gill arches- the skeletal elements that support the pharynx

12. Gill Arches

13. REVIEW!!! What class are the sharks found in?
What are gill arches? What do you think the importance of gill arches are?