1. WARM UP
Chordates are animals with some type of spinal cord and/or backbone. Make a list of 12 different chordates.

2. Chordate Cladistics

3. Cladogram Cladistics Cladogram
Classifying things based solely on shared characteristics
Cladogram
“Branch character”
Diagram showing how derived characteristics separate groups
Implies common ancestors

4. Vertebrae All chordates have a notochord
Nerves
Lampreys protect nerves with bones

5. Jaws and Fins Hagfish/lampreys are jawless Jawed fishes develop
Predators
Fins for rapid movement
Sharks, walleye, etc.

6. Limbs Coelocanths have lobe-fins Lobe-fins become limbs
Fleshy extensions of body
Lobe-fins become limbs
Weight-bearing

7. Lungs Bony fish have a swim bladder
Air sac
Amphibians use this for gas exchange

8. Scales
Amphibians are “slimy”
Reptiles have scales
Water conservation

9. Hair / Feathers Reptile scales develop into complex structures
For warmth and/or movement
Feathers
Hair

10. WRAP UP
Describe the key difference between each of the following pairs of animals:
Lamprey and shark
Crocodile and bird
Frog and lizard
Coelocanth and salamander