1. Phylum Chordata

2. Chordate Cladogram Section 30-1 Mammals Birds Reptiles Amphibians
Fishes
Nonvertebrate chordates
Invertebrate ancestor

3. Chordate Characteristics
All chordates at some point in their life cycle have:
-dorsal hollow nerve cord (brain/spinal cord)
-notochord (vertebral column)
pharyngeal pouches (pharynx)
tail extending beyond the anus

4. Subphylum: VERTEBRATA
About 96% of chordates are vertebrates
Approx. what % of all animals are vertebrates?
Internal framework called an endoskeleton made of cartilage or bone
Have a skull that protects the brain
Vertebral column or backbone that protects the spinal cord
Rib cage to protect internal organs
Most have two pairs of limbs
Most taxonomists divide vertebrates into seven classes.

5. 7 Classes of Vertebrates:
Class Agnatha – jawless fish ex: lamprey, hagfish *minimal skeleton, no true teeth
Class Chondrichthyes – cartilage fish ex: shark, skates & rays*entire skeleton is cartilage
Class Osteichthyes – bony fish *most fish belong to this group and their skeleton is made largely of bone ex: perch, carp, seahorse.
Class Amphibia – amphibians ex: frogs, toad, salemander *most have an aquatic larval stage (breath through skin/gills) and adults have lungs
Class Reptilia – reptiles ex: snakes, lizards, crocs *lay eggs on land
Class Aves – birds *have feathers, most fly, beaks/bills ex: hawk, heron, crow, emu
Class Mammalia – mammals *hair or fur and develop internally and nurse off milk after birth, 4 chambered heart ex: shrews, whales, bats, horses, tigers, elephants, rabbits, humans

6. Fish Agnatha: jawless fish Chondrichthyes: cartilage fish
Osteichthyes: Bony fish

7. Amphibians
Frogs
Toads
Salamanders

8. Reptiles
Snakes
Lizards
Crocodilians
Turtles

9. Aves:
The Birds

10. Mammalia: the mammals

11. Nonvertebrate Chordates
-These animals have no backbone, but do have a notochord.
-Also have a dorsal hollow nerve cord, pharyngeal pouches and a tail.
-Two sub-phyla: Urochordata and Cephalochordata
-Although very different from vertebrates, they are distant relatives

12. Urochordata: The Tunicates
-Filter-feeders
-Name comes from the tough covering called a tunic
-Called sea squirts
-Larvae have all four chordate characteristics
-Adult tunicates have no notochord or tail

13. Tunicate Larva -Notochord -Hollow dorsal nerve cord
-Pharyngeal pouches
-Tail

14. Cephalochordata: Lancelets
- Small fish-like animals that live in the sandy bottom.
-Have a head region with a mouth.
-Lancelets take water into their pharynx and pick out food.
-Pharynx has up to 100 pairs of gill slits
-Have a circulatory system but no heart. Blood is moved by the vessels.