1. What is fish with out an eye. FSH

2. History Earliest fish had no jaws and no paired fins-filtered feed
1st fish bodies covered with bony plates
For 100 million years-fish were the only vertebrates

3. Superclass Agnatha Jawless vertebrates
Most primitive, living vertebrates
Ostracoderms (extinct); lamprey and hagfish
Lack paired appendages; cartilaginous skeleton; notochord throughout life; rasping mouth

4. Superclass Gnathostomata, I
Placoderms (extinct): first with hinged jaws and paired appendages
Class: Chondrichthyes~ Sharks, skates, rays
Cartilaginous fishes; well developed jaws and paired fins; continual water flow over gills (gas exchange); lateral line system (water pressure changes)

5. Rise of Sharks & Bony Fish
About 400 mya all the other fish disappeared and were replaced by sharks and bony fish.
The jaws improved-developed the hyomandibular arch from gills
More fins developed.

6. Continue Sharks became the top predators-skeletons of cartilage
Sharks first fish with bony teeth
Sharks use internal fertilization and pups born alive
Skates and ray develop around 200 mya

7. Life cycles:
Oviparous- eggs hatch outside mother’s body
Ovoviviparous- retain fertilized eggs; nourished by egg yolk; young born live
Viviparous- young develop within uterus; nourished by placenta

8. Bony Fish
Evolved 400 mya
Developed heavy bony skeleton for protection and anchoring of muscles
Evolved in fresh water
Developed two types
Ray finned most fish perch- has swim bladder-95% of all fish are teleosts (advanced ray finned fish)
Lobe finned evolved 390 mya-fin is more like limb than fin-EX :Coelacanth

9. Some lobed-finned fish walk on land

10. Key Adaptations 1. Gills for breathing 2. Backbone
3. Single looped circulation system- blood is pump from heart to gills to body back to heart
Nutritional requirements fish are unable to make all the amino acids needed so they must get these amino acids by eating them- (true for all vertebrates)

11. Superclass Gnathostomata, II
Class: Osteichthyes
Ossified (bony) endoskeleton; scales operculum(gill covering); swim bladder (buoyancy)
Most numerous vertebrate
Ray-fined (fins supported by long, flexible rays): bass, trout, perch, tuna, herring
Lobe-finned (fins supported by body skeleton extensions): coelocanth
Lungfishes (gills and lungs): Australian lungfish (aestivation)

12. Bony Fish adaptations
Swim bladder secrets and absorbs gases in order to make fish rise or sink in water-gas is CO2
Lateral line system sensory organ located along the side of a fish (hearing)
Gill cover (operculum) hard plate covering the gills that pumps to push water over gills (so fish doesn’t have to swim to breath.)

13. Homework
Draw a picture of a fish and label each fin-determine what each fin does.