FISHES (yes, that

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FISHES (yes, thats the proper word)

• ICHTHYOLOGY (the study of fish)

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• MARINE VERTEBRATES FISHES CHAP 6.
• Read pgs. 177-187
• covering the topics of
• phylogeny, evolution and anatomy

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History of Ichthyology (dont write this, just
read)

• Aristotle made first written recordings and
  observations about fish (300s B.C.)
• For 2,000 years no work done on fish
• Then in 1500s, three scientists published new
  works on fish
• Led to rapid expansion in knowledge and new
  interest in study of fish
• Linneaus and modern classification of fish
• 20th century sees diversification of ichthyology

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Fishes Are Diverse (dont write this, just read)

• Live in diverse habitats
• Have different body shapes
• Have different body structures
• Have different reproductive strategies
• Have different feeding styles
• Inhabit multiple niches in life cycle

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Fishes are very diverse
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Im not kidding, they are really diverse
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I. GENERAL INFORMATION

• cold-blooded, vertebrate that breathe w/gills and
  move w/fins
• most numerous vertebrates more than 30,000
  species
• 400-500 in the reef area
• smallest
• Philippine Island Goby 1/3- 1/2
• largest
• Whale Shark 50 and several tons

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Diversity of Body Plan
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Diversity of Body Plan
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Common Body Plan Descriptors
Elongate, fusiform, or basslike
Compressed, compressiform, thin, narrow, deep, or
perchlike
Anguiliform, eellike, or attenuated
Depressed, depressiform, or flattened
Globiform, subcircular, or hemispherical
Ovate or truncated
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II. ANATOMY
A. Body shape

• Front Side
• FUSIFORM
• COMPRESSED
• DEPRESSED
• ATTENUATED

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II. ANATOMY
A. Body shape

• Front Side
• FUSIFORM
• COMPRESSED
• DEPRESSED
• ATTENUATED

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B. Mouth Position is significant

• ambush
• predator
• bottom feeder

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B. Mouth Position is significant

• ambush
• predator
• bottom feeder

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C. Feeding Patterns (pg. 187-191)

• Predators
• Nibblers- crushing teeth, may eat coral polyps
  and stone
• Strainers- plankton feeders
• Suckers- disc w/lips, barbels (whiskers) for
  searching the sand
• Parasitic- (external or internal) rasping teeth
  to penetrate scales
• ex. hagfish and lamprey
• ex. canduri or vampire fish -suck blood
  from gills
• read passage from text

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D. Know fin names and functions from handout
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FISH ANATOMY

• FINS movable structures that aid the fish in
  swimming and maintaining balance
• May be sharp, spiny or soft
• Most have Dorsal fin
• Anal fin
• Caudal fin (tail)
• Pectoral fin
• Pelvic fin
• Adipose fin
• (only some)

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Fish live(background information)

• 13 associated with open ocean
• 1 in surface (epipelagic) layer
• 5 in unlighted sections of water column
  (deepwater pelagic fishes)
• 7 on bottom (deepwater benthic fishes)
• 78 of marine fishes (44 of all fishes) live in
  narrow band along continents in water less than
  200m (continental shelf)

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Fish Diversity

• By volume 97 of all water is marine
• 58 of fish species are marine, 41 are fresh
  water
• Mainly due to speciation in response to isolation
  (ponds, lakes, rivers)
• Close to 80 of all marine species live in water
  along coastlines less than 200 m deep

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III. EVOLUTION

• Draw diagram from
• Marine Biology Text pg. 179
• Phylogenetic Tree
• (shows evolutionary relationships)
• Emphasis on Fish Classes

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EVOLUTION(background information)

• Earliest fish Ostracoderms
• fossils date to the Ordovician Period 425-450
  Million years ago
• slow, bottom-dwelling w/thick bony plates and
  scales, poorly developed fins and no jaws
• believed to be first animal w/a backbone
• became extinct 250 million years ago

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IV TAXONOMY

• Kingdom Animalia
• Phylum Chordata
• dorsal nerve chord
• Subphylum Vertebrata
• dorsal backbone made of cartilage or bone
• Classes
• Agnatha
• Chondrichthyes
• Osteichthyes

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Class Agnatha jawless

• Do not have a lateral line system
• Cyclostomes round mouths have neither plates
  nor scales
• Notochord, eel-like shape, a cartilaginous
  skeleton, and unpaired fins
• Lampreys
• - free living or parasitic adapted for
  sucking blood and body fluids of other fish
• - Feeding attach by suction, tear a hole with
  toothy tongue, secrete chemical to prevent
  clotting
• - do not have a stomach mouth, esophagus, a
  straight intestine, and associated glands
• Problem for great lakes sport and
• commercial fishermen

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Hagfish(for background information)

• Bottom dwellers in cold marine waters
• Scavengers of dead and dying fish on ocean bottom
• Feed by sawing the fish with its toothed tongue
  from the inside out
• Extremely flexible to avoid capture or to clean
  the slime off after self-defense secretions
• When not feeding they remain
  hidden in burrows on the ocean
  floor

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Class Chondrichthyes(cartilage fish)

• Sharks, skates, and rays
• They have skeletons of cartilage, not bone
• Also have movable jaws and skeletons with paired
  fins
• No swim bladder
• Sharks
• Sharks are scavengers that eat injured fish,
  carrion, garbage and other waste from ships as
  well as animals such as seals, turtles, birds,
  whales, crabs, and a wide range of fishes.
• The sharks mouth has 6 to 20 rows of
  backward-pointing teeth. They can detect blood
  from an injured animal as far as 500 miles away.
• They swim with a side-to-side motion of their
  asymmetric tail fins. Behind their heads are
  pectoral fins that jut out of their bodies like
  the wings of a plane.
• Gas exchange requires a continuous passage of
  water over a sharks gills.

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Rays and Skates
Meyrs video

• Skates are a family of flat-bodied rays found in
  warm and temperate seas. They have eyes located
  on the upper surface of the body while the mouth
  and gills are located on the lower surface.
• Their color makes them almost invisible because
  when another animal looks down on them, they are
  camouflaged with the darkness of the sea bottom.
  When looked up from underneath, the animal is
  camouflaged with the light from the sun.
• Water enter their gill through two openings
  called spiracles atop their heads. Most feed on
  mollusks and crustaceans.

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Osteichthyes (bony fish)

• Osteichthyes make up most of the vertebrate
  population in fresh water and in salt water.
• Ray-finned fishes have fins that are supported by
  the long bones called rays. They are the most
  familiar fishes and include snakelike eels,
  yellow perch, cave fish, herring, and lantern
  fish.
• Lungfishes have gills where gas exchange takes
  place between water and the blood. They burrow
  unto the mud and cover themselves in mucus to
  stay moist until the pond refills.

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• Lobe-finned fishes, or coelacanths, have paddle
  like fins with fleshy bases.

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• Lobe-finned fishes, or coelacanths, have paddle
  like fins with fleshy bases.

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V. PHYSIOLOGY (fishyology)

• Diffusion- moves O2 from water into the blood
  (hemoglobin)
• the LARGE SURFACE AREA of the gills facilitates
  diffusion the gills are HIGHLY VACULARIZED
• Lung fish- modified SWIM BLADDER vascularized.
  Gaseous O2 can diffuse into the blood stream.
  Some fish can gulp air.
• chromatophores (pigment cells)

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FISH ANATOMY

• GILLS organs on the side of fish that allow
  them to breath
• Water is drawn in through the mouth and out the
  gills
• Dissolved oxygen in the water is taken into the
  blood and carbon dioxide is released

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Draw and label the gill, gill arch, gill rakers
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FISH ANATOMY - EYES

• similar to other vertebrates, but differ in a
  couple of ways
• spherical lens
• no eyelids
• size of the eye depends on the amount of light
  reaching the eye
• Shallow water small eyes
• Deep water large eyes
• Dark caves blind

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FISH ANATOMY- ears, taste, smell, sensitive cells

• Have inner ears
• Have taste buds in their mouths, on their lips
  and on their body/fins
• Have highly developed sense of smell
• Fish react to changes in water pressure,
  temperature, currants and sounds w/pressure
  sensitive cells along a lateral line near the
  base of the tail

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Do fish drink water?

• Yes and No
• It depends on the type of water it lives in.

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• VI. REPRODUCTION synonym spawning
• Sperm milt
• Eggs roe
• Reproduction is determined by
• 1. Age and 2. Season
• Types?
• Egg laying - most bony fish
• Live bearing- internal fertilization and internal
  development. Not very common, pioneered by
  Chondrichthyes

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Reproductive strategies

• Hermaphrodites-
• Sex reversal- is it better to be female or male?
• Unique methods to protect laid eggs
• Camouflage
• Mouth incubation
• Guard the nest
• EXTERNAL INTERNAL
• DEVELOPMENT DEVELOPMENT

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• EXTERNAL INTERNAL DEVELOPMENT DEVELOPMENT
• Many eggs few eggs few eggs

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• EXTERNAL INTERNAL DEVELOPMENT DEVELOPMENT
• Many eggs few eggs few eggs
• No care guard incubate

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• EXTERNAL INTERNAL DEVELOPMENT DEVELOPMENT
• Many eggs few eggs few eggs
• No care protection incubation
• Few survive higher survive highest
  survive

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• EXTERNAL INTERNAL DEVELOPMENT DEVELOPMENT
• Many eggs few eggs few eggs
• No care protection incubation
• Few survive higher survive highest
  survive
• 10/1000 10/100 10/10
• ENERGY/ BENEFIT RATIO
• A limited amount of energy can be shared in
  different ways. of survival is different but
  overall numbers remain about the same