Transcript marine fishes

MARINE FISHES
WHY ARE THEY SO IMPORTANT
TO HUMANS?
SUBPHYLUM VERTEBRATA
 IN
PHYLUM CHORDATA
 NOTOCHORD = SPINAL COLUMN
 DORSAL HOLLOW NERVE CORD =
SPINAL CORD AND BRAIN
 POST ANAL TAIL
 GILL POUCHES = GILLS OR LUNGS
FISHES
 MAKE
UP OVER HALF OF ALL
VERTEBRATES
 3 CLASSES: AGNATHA,
CHONDRICHTHYES, OSTEICHTHYES
 HOW DO SOME FISH SURVIVE IN
BELOW FREEZING CONDITIONS? (227)
AGNATHA (JAWLESS FISH)
 MOST
PRIMATIVE
 CARTILAGENOUS SKELETON
 FEED BY SUCTION AND EXTENDING A
DENTAL PLATE WITH TEETH LIKE
STRUCTURES
 LACK PAIRED FINS AND SCALES
 EEL LIKE
HAGFISH
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MOSTLY SCAVENGERS SOME FEED ON LIVE
PREY (DENTAL PLATE)
FEED ON DEAD OR DYING FISH
MAY EAT FROM INSIDE OUT
BOTTOM DWELLERS (LIVE IN BURROWS)
PRODUCE SLIME THAT SUFFICAT
PREDATORS
MONECIOUS OR DIECIOUS
EXTERNAL FERTILIZATION
LAMPREYS
 BREED
IN RIVERS AND LAKES BUT
SOME MOVE TO SEA AS ADULTS
 LARVA MAY LIVE IN BURROWS FOR 3-7
YEARS BEFORE METAMORPHOSIS
INTO ADULT FORM
 ATTACH TO FISH AND SUCK THEIR
FLUIDS WITH DISK SHAPED MOUTH
WITH TOOTH LIKE STRUCTURES
CHONDRICHTHYES
(CARTILAGENOUS FISH)
 SHARKS,
SKATES, RAYS, CHIMERAS,
RATFISH
 SKELETON OF CARTILAGE
 VENTRAL MOUTHS
 DERMAL DENTICLES
 CALLED LIVING FOSSILS
SHARK CHARACTERISTICS
 PECTORAL FINS
(BERNOLI’S
PRINCIPLE) AND OILY LIVER FOR LIFT
 GILLS NOT PROTECTED (GILL SLITS)
 CONTINUE TO SWIM FOR OXYGEN
AND LIFT (NURSE SHARKS
EXCEPTION)
 SOME HAVE HETEROCERCAL CAUDAL
FIN FOR LIFT
OTHER SHARK
CARACTERISTICS
 NICTITATING
MEMBRANE OVER EYE
 ACUTE OLFACTORY SENSES DUE TO
2/3 OF CELLS IN BRAIN ARE USED FOR
PROCESSING SMELLS
 LATERAL LINE SYSTEM (TUBES THE
LENGTH OF BODY WITH NEUROMAST
CELLS THAT DETECT MOVEMENT)
 AMPULLAE OF LORENZINI (DETECT
ELECTRICAL CURRENTS)
DIGESTION
 TAKES
CHUNKS OF PREY, NO
CHEWING
 SPIRAL VALVE AIDS IN DIGESTION BY
ADDING SURFACE AREA
OSMOREGULATION
 RETAIN
UREA TO MAINTAIN SOLUTE
CONCENTRATION EQUAL OR
GREATER THAN SEA WATER
 RECTAL GLAND AND GILLS GET RID
OF EXCESS SALT
 SOME SHARKS CAN GO INTO RIVERS
REPRODUCTION
 CLASPERS
INSERT INTO CLOACA FOR
INTERNAL FERTILIZATION
 SHARKS MAY BE:
 OVIPAROUS (LAY EGGS; MERMAIDS
PURSE)
 VIVIPAROUS (LIVE YOUNG)
 OVOVIVIPAROUS (INTERNAL EGGS
AND LIVE BIRTH)
LARGEST FISHES
 WHALE
SHARK (60 FT)
 BASKING SHARK (50 FT)
 BOTH ARE FILTER FEEDERS
RAYS VS. SKATES
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FLAT BODIED, BOTTOM DWELLERS
(DEMERSAL)
GILL SLITS ON VENTRAL SIDE OF BODY
WING-LIKE PECTORAL FINS
STINGRAYS HAVE STINGING BARB AT BASE
OF TAIL
ELECTRIC RAYS = UP TO 220 VOLTS WITH
ORGANS ON HEAD
SKATES DON’T HAVE WHIP TAIL OR STING,
AND HAVE WAVE-LIKE MOTION WITH
PECTORAL FINS INSTEAD OF FLAPPING
RATFISH AND CHIMARAS
 HAVE
SKIN OVER GILLS LIKE AN
OPERCULUM
 TAKE WATER THROUGH NOSTRILS
AND OUT OF GILLS
OSTEICHTHYES (BONY FISH)
 MOST
FISH ARE BONY (98%); HALF OF
ALL VERTEBRATES
 BONY SKELETON
 CYCLOID (ROUND) SCALES
 OPERCULUM (GILL COVER)
 TERMINAL MOUTHS
 SWIM BLADDER (PRESSURE AND LIFT)
 MANUVERABLE FINS
SUBCLASS SARCOPTERYGII
(LOBE-FINNED FISHES)

LUNG FISH (HAVE PRIMATIVE LUNGS
INSTEAD OF SWIM BLADDER)
 COELACANTHS (THOUGHT TO HAVE BEEN
EXTINCT UNTIL DISCOVERED OFF THE
COAST OF MADAGASCAR)
 COELACANTHS ARE THOUGHT TO BE A LINK
BETWEEN FISH AND AMPHIBIANS BECAUSE
OF THEIR LOBE FINS (HOMOLOGOUS
STRUCTURES)
SUBCLASS ACTINOPTERYGII
(RAY FINNED FISH)
 HAVE
RAY FINS AND COMPRISE ALL
FISH OTHER THAN LUNG FISH AND
COELACANTHS
 CONTAIN A SWIM BLADDER
 MOST DIVERSE AND NUMEROUS
SUBCLASS OF FISH
BODY SHAPE
 DIRECTLY
RELATED TO THE HABITAT
THE FISH LIVES IN
 FAST FISH ARE HYDRODYNAMIC
(FUSIFORM BODY SHAPE; TUNA AND
MARLIN)
BODY SHAPE
 REEF
FISH ARE BUILT TO TURN AND
MANUVER (LATERALLY COMPRESSED
LIKE BUTTERFLY FISH AND TANG)
 FLAT FISH ARE BUILT FOR BOTTOM
DWELLING (FLOUNDER)
 SOME FISH ARE SHAPED FOR CAMO.
(STONE FISH, PIPE FISH)
COST OF TRANSPORT
 FRICTIONAL DRAG
(CAUSED BY
SURFACE OF FISH)
 FORM DRAG (CAUSED BY DIAMETER
OF FISH)
 TURBULANCE (CAUSED BY
MOVEMENT THROUGH WATER)
 THE LESS FISH HAVE OF THE ABOVE
FACTORS = LESS ENERGY USED
ASPECT RATIO
HEIGHT/FIN AREA)2
 CAUDAL FIN = TAIL FIN
 HIGHER THE RATIO THE FASTER THE
FASTER THE FISH
 FASTEST TO SLOWEST: FORKED,
LUNATE, HETEROCERCAL, TRUNCATE,
ROUNDED
 LIST 2 FISH PER FIN.
 (CAUDAL FIN
LOCOMOTION
 IDEAL BODY
FOR SPEED IS A FISH
WHOS LENGTH IS 4.5 TIMES GREATER
THAN ITS DIAMETER
 LOW COST OF TRANSORT COMBINED
WITH HIGH ASPECT RATIO = FAST
 “S” WRIGGLE IS BASIC FISH MOTION
 IT IS ACHIEVED MYOMERES (W
SHAPED MUSCLES THAT YOU LIKE TO
EAT)
FISH FINS
 ANAL,
DORSAL, PELVIC, AND
PECTORAL ARE TYPICALLY USED FOR
STABILITY
 CAUDAL FINS ARE USED FOR THRUST
 RAYS AND SKATES USE PECTORAL
FOR TRUST; SEA HORSES USE THEIR
DORSAL FINS
 REEF FISH TYPICALLY ONLY MOVE
THEIR FINS TO MOVE NOT MYOMERES
PHYSOCLIST VS.
PHYSOSTOMOUS SWIM
BLADDER
 PHYSOCLIST
SWIM BLADDER
RECEIVES GASES FROM THE BLOOD
 PHYSOSTOMOUS SWIM BLADDER
RECEIVES GASES FROM A
CONECTIVE TUBE THAT RUNS FROM
THE MOUTH TO THE BLADDER
COLORATION
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CHROMATOPHORES ARE COLOR CELLS
(SACKS OF PIGMENT)
IRIDOPHORES REFLECT LIGHT (CRYSTALS
INSIDE)
CAUSE FISH TO LOOK SHINY
COLORS ADVERTISE REPRODUCTION,
DANGER, BAD TASTE (POSTER COLORS)
REEF FISH HAVE CRYPTIC COLORATION
OPEN WATER FISH = OBLITERATIVE
COUNTER SHADING
FEEDING
 MAKE A LIST
OF VARIOUS TYPES OF
FISH AND THEIR FEEDING METHODS.
 WHAT IS FILTER FEEDING?
 WHAT ARE GILL RAKERS AND HOW
ARE THEY USED?
 WHAT DOES MOUTH POSITION HAVE
TO DO WITH THE TYPE OF FOOD
EATEN BY FISH?
SCHOOLING
 ABOUT
4000 SPECIES SCHOOL AS
ADULTS
 KEEP A CONSISTENT DISTANCE USING
LATERAL LINE
 LATERAL LINE IS A SERIES OF FLUID
FILLED PITS THAT SENSE PRESSURE
CHAGES IN THE WATER
 WHY DO FISH SCHOOL?
REPRODUCTION
 CARTILAGENOUS
FISH HAVE
INTERNAL FERTILIZATION: CLASPERS
ARE INSERTED INTO FEMAL CLOACA
 CLOACA IS A COMMON OPENING FOR
WASTE AND REPRODUCTION
 SPAWNING IS A FISHES FERTILE TIME
 SEX HORMONES READY THE
GAMETES AND FISH FOR SPAWNING
HERMAPHRODITISM
 SOME ARE
HERMAPHRODITES
 SOME HAVE SEX REVERSAL
TRIGGERED BY HORMONES TURNED
ON BY ENVIRONMENTAL FACTORS,
LIKE LOSS OF DOMINANT MALE OR
MATURITY TO A CERTAIN AGE OR SIZE
QUESTIONS
 NAME AND
DESCRIBE FIVE
DIFFERENT REPRODUCTIVE
STRATEGIES OF BONY FISH (PG 244246)
MIGRATION
 RELATED
TO FEEDING AND
REPRODUCTION
 ANADROMOUS = FRESH (BREEDING)
AND SALT (MOST OF LIFE) ; SALMON
 CATADROMOUS = SALT (BREEDING)
FRESH (MOST OF LIFE); EEL
QUESTIONS
 HOW
DO THEY NAVIGATE IN THE
OCEAN?
 DESCRIBE THE LIFE CYCLE OF THE
SALMON.
 DESCRIBE THE LIFE CYCLE OF THE
EEL. COMPARE THE AMERICAN AND
EUROPEAN EELS.