Phylum Chordata Phylum Chordata • Have a notochord in embryo

– Strong, rod-like structure that can bend

• Chordates include all of the vertebrates and two groups of invertebrates

Types of Chordates:

Invertebrates

1. Lancelets and tunicates

Vertebrates

1. Fish

2. Amphibians

3. Birds

4. Reptiles

5. Mammals

Invertebrate Chordates

http://evolution.berkeley.edu/

http://www.ramblincameras.com/

Tunicate Adult

Tadpole-likeSessile

Lancelet

Tunicate Larva

3quarksdaily.com

Chordates: FishesChordates: Fishes

• 4 groups of fish:– Lampreys– Hagfish– Cartilaginous fish (have flexible skeleton made of

cartilage) – examples sharks, rays– Bony fish (skeletons contain bone) – salmon, trout

• Fish breath through gills – Absorb dissolved oxygen in water

• Fish are Ectotherms– Cold blooded– Blood temperature changes with surroundings

Jawless, long & Snakelike, no scales

Fishes (continued)

• Swim bladder – gas filled sac, controls floating in fish

• Lateral line system – row of sensory organs that run on both sides of the body of fishes

• Operculum – protective flap that covers the gills of bony fishes