1. Introduction to Fish

2. Phylum Chordata Subphylum Vertebrata – Class Agnatha – Class Chondrichthyes – Class Osteichthyes – Class Amphibia – Class Reptilia – Class Aves – Class Mammalia fish

3. Class Agnatha - jawless fish: hagfish and lampreys absence of jaws no paired fins cartilaginous skeleton 2-chambered heart

4. Basic Anatomy Class Agnatha Possess medial nostril, medial fins, notocord rather than vertebral column 7 or more pr gill pouches present Light sensitive pineal eye Fertilization external Cartilaginous skeleton Lack jaws, paired fins, scales GI track w/out stomach Lampreys and hagfish 100 species

5. Agnatha

6. Class Agnatha Hagfish

7. Jaw Development agnathostome gnathostome 1 st appeared 400 mya

8. Jaws evolved from gill supports. Jaws developed from gill arches located around the pharynx. cranium mouth gill arches cranium mouth cranium mouth Jaws gave vertebrates a huge advantage as predators.

9. Only two groups of jawed fish still exist. Cartilaginous fish and bony fish are still in existence. Cartilaginous fish have skeletons made of cartilage.

10. Cartilaginous fish include the Holocephali and Elasmobranchs –Holocephali include ratfish, a small group of deep-sea fish. –Elasmobranchs include sharks, rays, and skates.

11. Basic Anatomy Class Chondrichthyes Posses jaws with teeth, cartilaginous skeleton, paired fins Scales (denticles) have same origin and composition as teeth Possesses 5-7 gills Spiral valve intestine Ureoosmotic strategy Electroreception Lateral line No swim bladder Heterocercal tail Relatively unchanged (480 mybp) Sharks, skates, rays

12. Cartilaginous fish

13. Chondrichthyes

14. Bronze whaler

15. Eagle ray

18. Chondrichthyes

19. Basic Anatomy Class Osteichthyes Posses jaws with teeth, bony skeleton, paired fins 4 paired gill arches covered by operculum Intestine- simple, no spiral valve Swim bladder Lateral line Homocercal tail Scales- cycloid, ctenoid

20. Bony fish

22. Swim bladder

25. Fish are vertebrates with gills and paired fins. Fish use specialized organs called gills to breathe underwater. – sheets of thick, frilly tissue filled with capillaries – take in dissolved oxygen from water, release carbon dioxide water flow

26. Countercurrent flow is the opposite movement of water against the flow of blood in the fish’s gills.

27. Circulatory system of fish

28. Bony fish have skeletons made of bone. –operculum protects a bony fish’s gills –movements of operculum help bony fish move water over gills

29. Fins are surfaces that project from a fish’s body. dorsal fin caudal fin anal fin pectoral fin pelvic fin –keep fish stable –redirect water around fish as it swims –help fish maneuver in water

31. T he source of propulsion for virtually all fish comes from: 1.Undulation of the body 2.Paired Fins: Pectoral Pelvic 3.Unpaired Fins: Caudal Dorsal Anal 4.A combination of the above Types of Fins

32. Anguilliform swimming (Undulation)

33. Dorsal & Anal Fin Propulsion

34. Anal Fin Propulsion Black ghost knifefish

35. Pectoral Fin Propulsion

36. Dorsal fin Bowfin Sea horse Knifefish

37. Pectoral Fin Frogfish

38. Walking catfish

39. Mudskipper

40. Myomeres – bands of muscle along sides of body contract pushing against water, forces body forward

42. Dorsal & anal fins – act as rudders to steer & provide stability (unpaired) Pelvic fins – to turn, balance, & “brake” (paired) ● Pectoral fins – steering (paired)

46. Fish senses

47. All fish have a lateral line system. –sensory system –sensitive to small changes in water movement lateral line

48. Lateral line system

49. Fish scales Reduce drag and direct water flow

50. Types of fish scales

51. General Life Style Categories a.pelagic cruisers 1.occurring in water column far away from the bottom (benthic) environment 2.often referred to as "blue water" 3.includes tuna, billfish, blue sharks, mackerel sharks (great whites and mako sharks) Fish Adaptations and Life Styles

52. b.demersal 1.bottom-associated fishes, but not usually sitting on the bottom 2.rely on the benthic environment as a source of food, place to reproduce, and/or place of refuge, etc. 3.includes most reef fishes (e.g., butterfly fishes, surgeon fishes, wrasses, parrot fishes, etc.)

53. c.benthic 1.bottom-dwelling fishes that spend the majority of time sitting on the bottom 2.includes flatfishes, lizard fishes, many scorpion fishes, many hawkfishes, gobies, etc.

54. tuna 1 ) fusiform a) = torpedo-shaped b) allows minimal drag while swimming c) best shape for a pelagic cruise Body shape

56. 2)compressed a)laterally flattened (e.g., butterflyfishes & surgeonfishes) b)allows for maneuverability in surge environments c)useful for demersal fishes that hover above the reef d)exception seen in flatfishes that lie on one side of the body as benthic fishes

57. John Dory: predator in waiting…

59. 3)elongated or attenuated a)long body (e.g., trumpetfish, cornetfish, eels) b)seen in demersal fish that either hover motionless in the water) c)seen also in benthic fishes (e.g., eels) that hide in holes in the reef

60. 4)depressed a)dorso-ventrally flattened (e.g., frogfishes, scorpionfishes & gobies) b)broad ventral surface facilitates resting on the bottom c)seen in many benthic fishes

61. Body Coloration 1)source of color a)pigment color - chromatophores for yellows, reds, oranges, browns, & blacks b)structural color - iridophores (reflection) & light refraction for blues, silvers, & rainbows

62. 2)patterns a)countershading 1)dark blue or black dorsally, white or silvery ventrally 2)results in blue water "camouflage“ 3)observed most frequently in pelagic cruisers

63. b)camouflage 1)matching the background coloration 2)usually involves having irregular dark blotches and spots 3)typically seen in benthic fishes, especially benthic ambush predators (e.g., frogfishes, gobies, & many scorpionfishes) 4)some fishes (e.g., flatfishes) may exhibit rapid color changes in response to different backgrounds

64. Cryptic colouration

65. b)camouflage 5) matching downwelling light Cookie cutter shark Hatchet fish

66. c)disruptive coloration 1)color pattern breaks up the silhouette of the fish 2)may involve dark bars across the eye and tail region 3)seen in many demersal fishes such as butterfly fishes

67. d)bars and stripes 1)bars are vertical (e.g., manini) 2)stripes are horizontal (e.g., ta'ape) 3)seen frequently in schooling demersal fishes 4)may confuse potential predators by making it difficult to select individual prey from the school

68. e)misdirection 1)false eye spots, etc. 2)observed in many demersal butterfly fishes

69. f)advertising coloration 1)bright, obvious color patterns 2)possible functions a)advertising a cleaning station (e.g., cleaner wrasses) b)advertising a warning (e.g., nohu) c)advertising for mates (e.g., male parrotfishes) Hawaiian cleaner wrasse Nohu

70. g)mimicry 1)imitating other creatures 2)seen in a few demersal and benthic fishes 3)examples a)blenny (Aspidontus taeniatus) mimics cleaner wrasses b)shortnose wrasse mimics Potter's angel which sports a defensive spine

71. g)mimicry 4)leafy sea dragon (Australia)

72. h)uniform red coloration 1)most often observed in deep-dwelling or night active demersal fishes 2)examples include opakapaka, oweoweo, menpachi, & squirrelfishes

73. i)noctural versus diurnal color changes j)male versus female color differences k)juvenile versus adult color differences Bluehead wrasse Dragon wrasse Stoplight parrotfish

74. Sex and social behaviour

76. Territoriality Black angel fish

77. Placoderm (395-345) lamprey & hagfish Ostracoderm (510-=350 mybp) Osteichthyes (395) Chondrichthyes (370) (360)

79. Coelacanth

81. Lungfish

82. New Zealand Fish Over 1,000 species, many in Indo-Pacific and Australia as well Of the 270 coastal species, approx. 25% are endemic

83. Triplefins Osteichthyes

84. Parore: Herbiverous fish feeding on kelps and other algae

85. Demersal fish live on the sea floor

86. Pelagic fish live in the water column above

87. Variations on a theme

89. Osteichthyes

91. Blue maomao : plankton feeders

92. Trevalley : plankton feeders

93. Snapper

94. Leatherjacket

95. Yellow-finned tuna

98. Placoderm (395-345) lamprey & hagfish Ostracoderm (510-=350 mybp) (360)