1. Fishes

2. Kingdom - Animalia Phylum - Chordata Subphylum - Vertebrata Vertebrates: Vertebrates: Include fish, amphibians, reptiles, birds, & mammals Include fish, amphibians, reptiles, birds, & mammals Have a notochord (slim, flexible rod) present in early stages that may be replaced by backbone in adults Have a notochord (slim, flexible rod) present in early stages that may be replaced by backbone in adults Contain a dorsal, hollow bundle of nerves called the nerve or spinal cord Contain a dorsal, hollow bundle of nerves called the nerve or spinal cord Respire through pharyngeal or gill pouches during early development Respire through pharyngeal or gill pouches during early development Have post-anal tail in early stages Have post-anal tail in early stages Endoskeleton made of bone &/or cartilage Endoskeleton made of bone &/or cartilage Anterior head with well developed brain & sensory organs (Cephalization) Anterior head with well developed brain & sensory organs (Cephalization) Closed circulatory system Closed circulatory system

3. Taxonomy of Vertebrates: Agnatha include hagfish & lamprey with long, eel-like bodies without jaws or paired fins & cartilage skeletons Agnatha include hagfish & lamprey with long, eel-like bodies without jaws or paired fins & cartilage skeletons Chondrichthyes include sharks, rays, & skates with cartilage skeletons, paired fins, & jaws Chondrichthyes include sharks, rays, & skates with cartilage skeletons, paired fins, & jaws Osteichthyes are bony fish with jaws, paired fins, & bone and cartilage in their skeletons Osteichthyes are bony fish with jaws, paired fins, & bone and cartilage in their skeletons Amphibia include frogs, toads, & salamanders that go through an aquatic larval or tadpole stage Amphibia include frogs, toads, & salamanders that go through an aquatic larval or tadpole stage Reptilia include snakes, turtles, lizards, & alligators that live on land, are covered with scales, & lay a tough, protective amniote egg Reptilia include snakes, turtles, lizards, & alligators that live on land, are covered with scales, & lay a tough, protective amniote egg Aves are birds covered with feathers, adapted for flying, & with hollow bones Aves are birds covered with feathers, adapted for flying, & with hollow bones Mammalia have hair or fur & females have mammary or milk-producing glands Mammalia have hair or fur & females have mammary or milk-producing glands

4. Evolution: Fossil record shows jawless fish without paired fins appeared first about 550 million years ago Fossil record shows jawless fish without paired fins appeared first about 550 million years ago Ostracoderm was a jawless, bottom-feeding ancestor to the agnathans (modern jawless fish) Ostracoderm was a jawless, bottom-feeding ancestor to the agnathans (modern jawless fish) Development of jaws & paired fins allowed better movement & increased ability to capture prey Development of jaws & paired fins allowed better movement & increased ability to capture prey Extinct acanthodians or spiny fish were first jawed fish with paired fins Extinct acanthodians or spiny fish were first jawed fish with paired fins Jaws probably developed from gill arches (bone that supports the pharynx) Jaws probably developed from gill arches (bone that supports the pharynx)

5. Ostracoderm

6. Acanthodian

7. Characteristics of Fish: Streamlined body & muscular tail for swimming Streamlined body & muscular tail for swimming Most with paired fins for maneuvering Most with paired fins for maneuvering Body covered with protective scales & mucus layer to reduce friction when swimming Body covered with protective scales & mucus layer to reduce friction when swimming Have less dense body tissues & store less dense lipids to help them float Have less dense body tissues & store less dense lipids to help them float Respire through gills Respire through gills Most have a lateral line system or a row of sensory structures running down each side of the organism to detect changes in water temperature, pressure, current, etc. Most have a lateral line system or a row of sensory structures running down each side of the organism to detect changes in water temperature, pressure, current, etc. Most with well-developed sense of sight & smell Most with well-developed sense of sight & smell Some can detect electrical currents Some can detect electrical currents Ectotherms (adjust body temperature to environment) Ectotherms (adjust body temperature to environment) Two chambered heart (upper atrium receives blood & lower ventricle pumps blood) Two chambered heart (upper atrium receives blood & lower ventricle pumps blood)

9. Agnatha (Jawless Fish): Agnatha (Jawless Fish): Hagfish (live in oceans) & lampreys (found in marine & freshwater) Hagfish (live in oceans) & lampreys (found in marine & freshwater) Hagfish Circular mouths Circular mouths Sharp teeth & strong rasp-like tongue to tear hole in prey & suck out blood & body fluids Sharp teeth & strong rasp-like tongue to tear hole in prey & suck out blood & body fluids Known as cyclostomes Known as cyclostomes Eel-shaped body Eel-shaped body Mucus covers body Mucus covers body Skeleton made of cartilage Skeleton made of cartilage No paired fins No paired fins Gills without bony cover (called operculum) Gills without bony cover (called operculum) Retain their notochord throughout their life Retain their notochord throughout their life Hagfish are bottom dwellers in cold marine waters that burrow in mud, scavenge on dead & dying fish, & have tentacles around their mouth Hagfish are bottom dwellers in cold marine waters that burrow in mud, scavenge on dead & dying fish, & have tentacles around their mouth Lampreys are usually parasites with a keen sense of smell to locate prey, lay their eggs in freshwater streams, & are covered with a poisonous slime Lampreys are usually parasites with a keen sense of smell to locate prey, lay their eggs in freshwater streams, & are covered with a poisonous slime Lampreys

10. Chondrichthyes Includes sharks, rays, & skates Includes sharks, rays, & skates Endoskeleton of cartilage Endoskeleton of cartilage Hinged jaws & paired fins Hinged jaws & paired fins Placoid scales & tooth-like dermal spines on scales Placoid scales & tooth-like dermal spines on scales Marine Marine Carnivorous Carnivorous Sharks are torpedo shaped Sharks are torpedo shaped Rays & skates have broad, flat bodies with wing-like fins and a tail Rays & skates have broad, flat bodies with wing-like fins and a tail

11. Placoid scales & tooth-like dermal spines on scales

12. Shark Characteristics: Fast swimmers Fast swimmers Large, oily liver (20% of body weight) makes them buoyant Large, oily liver (20% of body weight) makes them buoyant Tough, leathery skin Tough, leathery skin Fierce predators Fierce predators Whale shark is largest & filter feeds on plankton Whale shark is largest & filter feeds on plankton Ventral mouth with 6-20 rows of sharp, replaceable teeth Ventral mouth with 6-20 rows of sharp, replaceable teeth Short, straight intestine with spiral valve to slow food movement Short, straight intestine with spiral valve to slow food movement 5-7 pairs of gills for gas exchange 5-7 pairs of gills for gas exchange Kidneys remove wastes & maintain water balance Kidneys remove wastes & maintain water balance Electroreceptors on head help find prey & navigate Electroreceptors on head help find prey & navigate Lateral line along side of body contains sensory cells to detect vibrations & pressure Lateral line along side of body contains sensory cells to detect vibrations & pressure Separate sexes with external fertilization Separate sexes with external fertilization

14. Ray & Skate Characteristics: Usually harmless to humans Usually harmless to humans Broad, wing-like pectoral fins used to glide through water Broad, wing-like pectoral fins used to glide through water Flattened bodies with ventral mouth Flattened bodies with ventral mouth Both eyes on top of head Both eyes on top of head Have protective coloration (darker on top & lighter on bottom) Have protective coloration (darker on top & lighter on bottom) Feed on fish & invertebrates Feed on fish & invertebrates Stingray with poison spine by tip of tail Stingray with poison spine by tip of tail Electric ray gives off strong, electric shock Electric ray gives off strong, electric shock Manta ray is largest Manta ray is largest

15. Manta Ray

16. Traits of Bony Fish (Osteichthyes) Skeleton made of bone Skeleton made of bone Hinged jaws Hinged jaws Paired fins Paired fins Gills for gas exchange Gills for gas exchange Lateral line Lateral line Body covered with scales & mucus coating Body covered with scales & mucus coating Includes lobe-finned, ray-finned, and lung fish Includes lobe-finned, ray-finned, and lung fish

17. Lobe-finned Fish: Muscular, paddle-like fins supported by bone Muscular, paddle-like fins supported by bone Gills Gills Known as coelacanths Known as coelacanths Thought to be extinct until 1938 when species found in Africa Thought to be extinct until 1938 when species found in Africa Live in deep oceans Live in deep oceans

18. Coelacanths

19. Lungfish: Use lungs & gills Use lungs & gills Eel-shaped body Eel-shaped body Live in shallow, tropical rivers of Africa, Australia, & South America Live in shallow, tropical rivers of Africa, Australia, & South America Come to surface & gulp air when oxygen level is low Come to surface & gulp air when oxygen level is low Form mud cocoon & become dormant if stream dries up Form mud cocoon & become dormant if stream dries up

20. Lungfish

21. Ray-finned Fish: Fan-like fins supported by rays Fan-like fins supported by rays Includes salmon, perch, catfish, tuna, etc. Includes salmon, perch, catfish, tuna, etc. Body covered with round, overlapping cycloid or ctenoid scales & mucus Body covered with round, overlapping cycloid or ctenoid scales & mucus Four sets of gills covered by bony operculum Four sets of gills covered by bony operculum Have movable fins Have movable fins Dorsal fin(s) located on top keep fish upright & used for defense Dorsal fin(s) located on top keep fish upright & used for defense Caudal fin or tail moves side to side to help steer Caudal fin or tail moves side to side to help steer Pectoral fins (paired) on each side behind the operculum Pectoral fins (paired) on each side behind the operculum Pelvic fins (paired) on ventral surface near the head Pelvic fins (paired) on ventral surface near the head Anal fin (single) behind anus Anal fin (single) behind anus

22. Ray-finned Fish cont… Swim bladder is thin-walled sac in abdomen that creates buoyancy from diffusion of dissolved gas from blood Swim bladder is thin-walled sac in abdomen that creates buoyancy from diffusion of dissolved gas from blood Kidneys filter the blood & help maintain water balance Kidneys filter the blood & help maintain water balance Ectothermic - body temperature regulated by the environment Ectothermic - body temperature regulated by the environment Keen sense of smell (nostrils) & have chemical receptors over the body Keen sense of smell (nostrils) & have chemical receptors over the body Can detect the earth's magnetic field as a guide to navigate oceans Can detect the earth's magnetic field as a guide to navigate oceans Have separate sexes with external fertilization Have separate sexes with external fertilization Eggs hatch into fry Eggs hatch into fry

24. Salmon Life Cycle: Migrate up to 3200 kilometers following magnetic cues in the ocean Migrate up to 3200 kilometers following magnetic cues in the ocean Follow mucus trails when navigating rivers Follow mucus trails when navigating rivers Return to birthplace to spawn Return to birthplace to spawn Males change color & jaw lengthens & develops a hook Males change color & jaw lengthens & develops a hook Female uses her tail to build gravel nest & lays up to 10,000 eggs Female uses her tail to build gravel nest & lays up to 10,000 eggs Male deposits sperm over eggs Male deposits sperm over eggs Adults usually die after spawning Adults usually die after spawning Pacific salmon return to sea when 15 cm long; while Atlantic salmon may stay in river up to 7 years Pacific salmon return to sea when 15 cm long; while Atlantic salmon may stay in river up to 7 years Secrete mucus coating in river as return to sea Secrete mucus coating in river as return to sea May stay in ocean 6 months to 5 years May stay in ocean 6 months to 5 years

26. Anadromous fishes spend most of their lives in the ocean but migrate to fresh water to spawn. Salmon, smelt, shad, striped bass, and sturgeon are common examples Anadromous fishes spend most of their lives in the ocean but migrate to fresh water to spawn. Salmon, smelt, shad, striped bass, and sturgeon are common examples Catadromous fishes live in fresh water but migrate to the ocean to breed. Most of the eels are catadromous. Catadromous fishes live in fresh water but migrate to the ocean to breed. Most of the eels are catadromous.

27. Forms of Reproduction Oviparous animals are animals that lay eggs, with little or no other embryonic development within the mother. Oviparous animals are animals that lay eggs, with little or no other embryonic development within the mother. Ovoviviparity, ovovivipary, or ovivipary, is a mode of reproduction in animals in which embryos develop inside eggs that are retained within the mother's body until they are ready to hatch. Ovoviviparity, ovovivipary, or ovivipary, is a mode of reproduction in animals in which embryos develop inside eggs that are retained within the mother's body until they are ready to hatch.

28. Vivipary has two different meanings. In animals, it means development of the embryo inside the body of the mother, eventually leading to live birth (as opposed to laying eggs). Vivipary has two different meanings. In animals, it means development of the embryo inside the body of the mother, eventually leading to live birth (as opposed to laying eggs).