Fishes and Amphibians Flashcards

1
Q

Living my jawless fishes are known as …

And include what species?

A

Cylcostomata

(Round mouth)

Hagfish
Lampreys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a fish?

A

Aquatic vertebrate will gills, appendages in the form of fins (if present), and usually the skin is covered in scales

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Fish vs fishes

A

Fish refers to one or more individuals of a species

Fishes refers to more than one species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What species with fish like names are not actually fish

A

Jellyfish, starfish, crayfish, shellfish

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Specific challenges of aquatic environment

A

-water is 800 times denser than air
-most fished adjust to salt and water balance of environment
-gills extract oxygen from water (water has 1/20th of the oxygen in air)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Clade Cyclostomata specific adaptations for hagfishes and lampreys

A

Hagfish: knot tying and slime

Lamprey: parasitism, best building

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When did Cyclostomata appear

A

Ancient fishes that hbu exchanged little over 400-450 my

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

External characterisitcs of jawless living fish

A

-body is slender and eel like
-skin naked (no scales)
-caudal fin
-pore-like hill openitna
-distinct head: tripartite Brian encoded in cartilaginous skull

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What do jawless fish not have?

A

Jaws, paired nostrils, paired fins, mineralized tissues (bone, teeth)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Hagfish and lamprey internal characteristics

A

-adults have notochord
-rudimentary vertebral elements (cartilage)
-pharyngeal muscles power gills for respiration
-keratinized “teeth” structures on tongue or oral hood (lamprey): not real teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Nostril in hagfishes and lamprey

A

Nasohypophyseal opening

One nostril that contains olfactory epithelium to smell. The opening for the nostril connects to the pharynx, so that hagfishes CNS breathe through their nostril!!!

In lampreys too( but does not connect to pharynx so lampreys cannot breathe through nostril

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Posterior to the nasal sac in hagfishes is the ______

A

Adenohypophysis (anterior pituitary)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Barbel

A

Whisker like sensory organ in hagfish

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Lamprey features not present in hagfish

A

Dorsal fun
Eyes are more developed in lamprey (pineal eye)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Habitat of Hagfish

A

Marine, worldwide
Deep water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are hagfishes overfished for

A

Eel leather or food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Hagfish feeding

A

Scavengers: large numbers of hagfish are quickly attracted to the smell of dead or dying fishes or other animals (whales), enter body of animal.

Use keratinized “teeth” on tongue to rasp bits of flesh from prey

Tie into knot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How do hagfish escape capture

A
  1. Tie themselves in knots for leverage to heal press or escape
  2. Slime!!!! To choke prey. Scrape off with knot after (produces from muscles glands)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Hagfish slime parts

A

-70-200 slime glands secrete mucin (mucous) and protein threads, each contained in separate cells
-when they contact water, Mucin absorbs water and threads unfurl to bind mucin into continuous mass of slime

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How do hagfish reproduce

A

-not much known: don’t reproduce in captivity
-females outnumber 100 to 1, some are heterotrophic
-females produce yolky eggs that attach to the bottom of sea
-eggs take 5 months to hatch into hagfish: no larval stage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Latin name for lampreys means what?

A

Rock licker
Petromyzontiformes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Lifestyle of lampreys

A

Anadromous

Live as adults in oceans or large lakes, ascend rivers and streams to breed, then die

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Lamprey feeding

A

Most are parasitic (adults)
-use suction of oral hood to attach to host
-sharp keratinized teeth and rasping tongue drill hole
-oral gland secretes anticoagulant
-don’t kill host, but leave weakened

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How do lamprey respirate

A

Flow through ventilation: applies to larva and adult not attached to prey: draws water into mouth and pumps out through gills

Tidal ventilation: when attached to host, acquire oxygen by moving water in and out of gills

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Characteristics of non-parasitic lamprey

A

-small (<20cm)
-inhabit small streams
-poorly developed teeth
-brief adult period (<6 months)
-don’t feed as adults
-spawn, then die

Northern Brook lamprey

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

3 Manitoba species of lamprey

A

-chestnut (parasitic)
-silver (parasitic)

Both above about 35cm

-northern brook (non parasitic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Lamprey nest building and spawning

A

-male begins building nest, and is joined by the female
-use oral hood to life rocks, and vibrations to remove debris
-female lays eggs and male fertilize
-monogamous
-die after spawning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

How do male Lamprey attract females and mate with them

A

-Male dorsal adipose ridge tissue that heats up 0.3° when female is present: Rope tissue
-pheromone to attract females to area
-Thermogenic secondary sex characterisitc

-males rub rope tissue over females abdomen and if she agrees she will rub her Urogenital pore against the tissue in return.
-male then wraps around her tightly, bites onto her head and locks into her by tying a knot with tail.
-both release sex cells together and fall into nest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Lamprey life cycle steps

A
  1. Large number of small eggs hatch, larvae leave nest at 1cm long and burrow into sand (Ammocoetes)
  2. Ammocoetes live sedentary in fresh water burrows and filter feed for 3-7 years
  3. Metamorphosis: over two months, become parasitic
  4. Parasitic growing stage: emerge as small (13cm) adults. Lasts 1-3 years and they feed on large fish
  5. Reproduce and die in streams
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Sea lamprey effect on Great Lakes

A

-originally only in eastern lakes, but human made canals connected them to all 5 of the great lakes
-negative effect on native fish species starting 1930 and still today
-Trout population diminished

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Sea lamprey control methods

A

Larvacides: chemicals to reduce larvae in spawning streams

Possibility of using pheromones to attract females away from males or trap them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Most modern day fish, except the lampreys and hagfish are part of the Clade called _________

A

Gnathostomata

Jawed vertebrates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Conodonts

A

Soft-bodied animal with mineralized teeth (high proportion of hydroxyapatite, which gives harness to teeth)

Extinct jawless fishes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

When were conodonts around

A

300mya

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Ostracoderms characteristics

A

Groups of jawless fish

-Dermal armours (exoskeleton) in form of large plates that cover head and sometimes the pectoral region or covered a portion of the body

-jawless

-more derived forms had paired pectoral fins (no paired pelvic fins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Ostracoderms time period

A

-orodovician (period followed the Cambrian until end of the Devonian)

Mass extinction at end of Devonian wiped them out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Placoderms

A

-plate like dermal armour covering the front 1/3 to half of the body

-paired pelvic and paired pectoral fins
-lower jaw resembles jawed vertebrates
-inner ear with 3 semicircular canals
-external organs (clasper)
-presence of an external reproductive organ (internal fertilization)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Example species of Placoderms

A

DUNK

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Are placoderms true Gnathostomes

A

Yes - bones forming upper had are homologous to bones in gnathostome jaw

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

When did placoderms go extinct

A

End of Devonian in mass extinction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Evolution of the jaw

A
  1. Basal gnathostomes: placoderms. Lower jaw resembles gnathostomes
  2. More derived placoderms: have a maxilla and pre maxilla bones in upper jaw
  3. Cartilaginous fishes (lost bony skull)
  4. Crown gnathostomes: include ray-finned and lobe-finned fish (includes tetrapods)-retain bony skull and these are refined
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Phylogeny of early vertebrates

A
  1. Cyclostomata: lamprey and hagfishes: evolutionary oldest extant vertebrates
  2. Conodonts: jawless, with mineralized teeth, long fossil record into Mesozoic
  3. Ostracoderms: jawless, abundant; extinct by end of Devonian
  4. Placoderms: jaws, abundant until end of Devonian
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Advantages of paired fins

A

-thrust, steering and stability in three dimensions
-tail fin-> primary thrust
-Anal and dorsal fins->lessen rotation or side to side swing
-pectoral and pelvic -> control vertical tilt; act as brakes, occasional thrust

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Dermal bone

A

Ossification of cells of skin with no cartilaginous precursor
-forms exoskeleton
-head shield or scales of ostracoderms
-most of our skull plates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Endochondral bone

A

-Begins as cartilage, then ossifies
-forms Endoskeleton

-vertebrae of bony fish and tetrapods
-fin or limb bones in fish or tetrapods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Are fin rays dermal or Endochondral

A

Dermal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Jaws enabled what?

A

Active foraging
Supported higher levels of activity
Predators to capture prey that are larger than themselves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Upper and lower jaws develop from _____

Hyoid develops from

A

Pharyngeal arch (Mandibular arch)

2nd arch (hyoid arch) and helps brace jaws

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Jaws and nostril development in Cyclostomes and Gnathostomes

A

Single nasohypophyseal placode blocks migration of Mandibular tissue around mouth
-one opening and placode for nose and anterior pituitary

Separation between 2 nasal palcodes and hypophyseal placode
-gives room for Mandibular cells to migrate and form upper jaw

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

The fossil record supports the hypothesis that jaws cannot develop until ……

A

Two nostril have formed with a separation in the location of the anterior pituitary

Need 2 nasal openings and separated anterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Why did jaws arise

A
  1. Enable animals to prey on large and active animals
  2. Improved ventilation- changes in Mandibular arch made it possible for fish to close their mouths. Closure of the mouth may have been an early step in creating a “double-pump” system of hill ventilation still used in jawed fishes today.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Chondrichthyes

A

Cartilaginous fishes
-ancient group appearing before Devonian
-living forms are highly derived
-about 1200 extant species in 2 lineages

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

2 lineages of Chondrichthyes

A

Elasmobranchii: sharks, skates, rays

Holocephali: chimeras

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Elasmobranchii skeleton, and teeth, and body covering

A

-cartilaginous skeletons with crystalline calcium including the skull: chondrocranium

-loss of dermal bone:

-teeth and placoid scales: thick tough mineralized scales known as placoid scales or dermal denticles. Teeth evolved from the dermal placoid scales

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Elasmobranchii respiration

A

Gills to absorb oxygen from the water
-5 full slits on both sides of the body
-spiracle: water pumped into small hole behind eye as another way for water to enter body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Elasmobranchii and an _______ mouth

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What helps Elasmobranchii locomotion

A

-fusiform shape: streamline body and placoid scales reduce drag
-heterocercal tail: vertebral column extends into dorsal lobe of tail
-enormous oily bodies in liver reduce density as sharks otherwise sink due to heavy body and no gas bladder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

How do Elasmobranchii deal with their loss of teeth

A

Teeth replacement
-Polyphyodont: continual teeth replacement.
-sharks replace teeth every 8 days
-Tooth whorl: conveyer belt of new teeth ready to go behind current teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Jaw suspension and profusion of Elasmobranchii

A

-hyostalic jaw suspension: derived form of jaw suspension in which the upper jaw moves independently of the cranium

Advantage: animal expands and protrudes jaw giving it ability to catch larger prey

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Gaelomorphii shark: Whale shark

A

-up to 19m in length: largest non-mammalian vertebrate
-mostly filter feeder of Plankton
-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Galeomorphi shark: Hammerhead Shark

A

-distinct head serve to enhance directional sensitivity of neuromasts (lateral line) and electro receptors in ampullae or olfaction
-grow more than 6M

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Gaelomorphii sharks: walking sharks

A

-walk around on sea floor bottom on search of small crustaceans or fish

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Squalomorphii sharks: Greenland shark

A

-longest life expectancy of vertebrates at 392 years
-reach sexual maturity at 150 years
-can grow larger than 6.5m
-slow swimmer with presumed slow metabolic rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Squalomorphii shark: cookie cutter shark

A

-<50cm long
-deep water
-feeds by biting pieces of flesh of sharks, tuna and dolphins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

_____% of Elasmobranchii are….

A

Skates and rays

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Habitat and body form of rays and skates

A

-sea floor life
-dorsal-ventral flattened body: enlarged pectoral fins for locomotion
-mouth and gills on ventral side, spiracle on dorsal side
-flattened teeth for crushing crustaceans, molluscs and echinoderms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Skates vs rays

A

Skates:
-rounder body
-long, thick tail with two dorsal fins and one caudal fin
-oviparous (egg laying)

Rays:
-kite body shape
-thin, whip lash like tail
-fins replaced by enlarged serrated, venomous barbs
-viviparous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Holocephalli: the chimeras unique traits

A

-live in deep water
-dense concentration of mechano and electro receptors on head and rostrum to detect prey
-3 pairs of continuous growing flat tooth plates
-mixed diet of crustaceans, echinoderms and fishes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

How is sound different in water than air

A

Travels 4x faster

70
Q

Two senses highly effective in water but not air

A

-Mechanoreceptors: water is more dense than air so movements make currents and can then be perceived. Lateral line helps detect these

-Electroreception: water is a good conductor of electricity.

71
Q

Mechanoreceptors

A

-Touch, pressure, motion and sound detector
-include the lateral line and inner ear

72
Q

Lateral line and inner ear rely on what sensory unit?

A

Sterocillia within hair cells

Mechanoreceptors within sensory hair cells detect movement of fluid resulting from motion in water external to the animal or from a change in the body’s position

Not actually made of hair!!! They are cilia

73
Q

What does the vestibular apparatus of inner ear do in sharks?

A

Detects movement of fluid in the ear caused by own body’s movement

-semi-circular canals: 3 canals arranged at right angles, which detect motion of the head in any direction
-otolith organs (sacculus and utricle): detect linear acceleration

74
Q

Shark hearing

A

-sound passes through body to sensory “hair cells” in inner ear
-hear frequencies of 10-800hz (low frequency

75
Q

Lateral line system

A

Series of canals over the head and along the body, with water entering through surface pores to contact neuromast organs
-neuromasts have clusters of Mechanoreceptors in “hair cells” that detect water movement and low frequency vibrations and transmit them to nerve cells
-localize prey and predators

76
Q

Electroreception

A

-shark and ray heads and pectoral fins of rays have electroreceptors (ampullae of Lorenzini) that detect bio electric fields of animals
-modified lateral line system
-gel-filled canal conducting electricity from surface pore to ampullae receptor) , which is attached to nerve

77
Q

Shark eye adaptation to aquatic environment and low light light conditions

A

-aquatic: spherical lens focuses image on retina: muscle moves lens towards or away from retina

-low light:
-high concentration of rods, photoreceptors
-tapetum lucidium: reflective layer behind the retina that enables light to bounce off retina a 2nd time so more photons can be absorbed

78
Q

Shark sensory structures for short, middle and long distances

A

Short <20cm: electroreception

Middle: vision and sound

Long >700cm: Olfaction, Mechanoreceptors: turbulence and low frequency vibrations

79
Q

2 characteristics of sharks, rays and skates reproduction

A
  1. Dioecious-separate male and female individuals, or hermaphrodite capable of being female or male but are not typical.
  2. Internal fertilization: claspers: sperm transfer
80
Q

Oviparity

A

40% of sharks and all skates
-large eggs in protective cases
-nourished by yolk sac
-no parental care
-young “fully formed”

Higher fecundity-larger offspring numbers compared to viviparous sharks

81
Q

A gland at the end of the mothers oviduct secretes:

A

A proteinaceous case around egg and it hardens after a few hours in contact with sea water

Have tendrils to help egg stay in position in crevices or vegetation

Organic waste flushed out of case through small opening; water and oxygen enters

82
Q

An egg case surrounds a ______ and ____

A

Single embryo

Yolk sac

Distinct in different species

83
Q

Viviparity

A

-many sharks (60%) and all rays

-embryo retained in reproductive tract
-more common in larger species which have larger young
-gestation can take 1-2 years
-uterus protects embryos from predation
-no parental care after birth

84
Q

Two types of viviparity

A

Ovo-viviparity: yolk sac or aplacental viviparity
-mother gives birth to live young, but embryos rely entirely on yolk sac for nutrition until birth

Matrotrophy or placental viviparity: mother supplies energy to embryo, for example: protein rich uterine secretions, placental connection so offspring receives nutrients from mothers blood, consumes additional resources produced by mother (eggs, siblings)

Combination: embryos of many species obtain energy from both sources

85
Q

Siblicide before birth in tiger sharks

A

-Females mate with multiple males to produce embryos with different fathers
-multiple embryos develop in each of 2 uteri
-first and largest embryo consumes siblings of other eggs in each uterus

Possible competition between males to father young after fertilization

86
Q

Reproductive specialization in sharks and rays

A
  1. Internal fertilization ensures no gametes float away
    2.invest heavily into young at stage of egg production and when carrying the embryo or egg before birth
    3.no larval stage
  2. Parental care ends at birth
  3. Produce fewer offspring at one time, but offspring have high survival
87
Q

Life history characteristic’s

A

-offspring per reproductive episode (fecundity)
-number of reproductive episodes
-age of maturity
-duration of life span

88
Q

Fast vs slow life history

A

Fast: small snails that develop quickly, produce large number of eggs and has a short life

Slow: large animal that takes years to mature, produce small number of offspring, has few reproductive episodes and has a long life span

89
Q

Sharks have what type of life history

A

Slow

90
Q

Slow life history connection with conservation

A

Slow life history especially low reproductive rate means that a population will have trouble recovering once it is reduced in numbers

91
Q

Exploitation of sharks

A

-100m killed by humans years year, mostly for the fins
-also killed for meat (fish and chips), cartilage or as by-catch

92
Q

Shark finning

A

Traditional and most common practice is to cut fins, then discard animal into the ocean

-inhumane
-ecological consequence of removing a top predator

93
Q

Canada and shark finning

A

Banned in 1994, but imports are allowed

Banned imports of shark fins in 2019

94
Q

What is helping sharks in conservation

A

-Banning finning and imports of fins
-shark ecotourism brings in a ton of money and expected to grow more! Therefore making them worth more alive.

95
Q

Osteichtyes meaning

A

Jawed fishes

96
Q

All major lineages of fishes, extant and extinct, coexisted during what time period

A

Devonian (419-359mya)
-jawless
-jawed
-jawed and bony

97
Q

Two extant groups of bony fishes

A

Sarcopterygii-lobe finned fishes

Actinopterygii-rated finned fishes (include teleost with 98% of modern fishes

98
Q

Bony fishes compared to cartilaginous fishes have what characteristics?

A

-bony fishes coming in fresh and marine water
-usually bilaterally flattened
-enodondral bone
-scales are softer or smoother
-no spiracle
-external fertilization (usually)
-larger number of eggs

99
Q

Key characteristics of bony fishes

A
  1. Fully ossified skeleton (vertebrae and appendages) made of Endochondral bone
  2. Dermal bone surrounds braincase
  3. Dermal jaw bones bear teeth
  4. Operculum over gills increases respiratory efficiency
  5. Gas bladder
100
Q

Operculum helping respiratory efficiency

A
  1. Operculum closed, mouth opens to draw water in
  2. Outward movement of operculum created negative pressure (suction) that draws water across the gills, and out
  3. Oxygen absorbed through gills into bloodstream (countercurrent flow)

Some fish able to extract 85% of oxygen from water

101
Q

Gill raker function

A

Strain out food and debris

102
Q

Ram ventilation

A

Fishes like sharks that rely on swimming forward and constant motion to force water through the open mouth and across gills

Operculum ventilation prevents this

103
Q

Gas bladder for respiration, buoyancy or both

A

-adjust volume of gas to achieve neutral buoyancy
Ascend: let gas out of bladder
Descend: mechanisms to move oxygen from blood vessels to gas bladder

Started as out-pocket of gut or esophagus

104
Q

Lobe finned fishes ancestral and modern trait comparison

A

-early forms had lungs and gills; modern have lungs except coelocanth
-ancestral forms had fleshy, strong paired fins
-ancestral forms had heterocercal tails; living forms have diphycercal tails

105
Q

When were lobe finned fishes most diverse

A

Devonian

106
Q

Tail variation

A

-heterocercal: extant sharks, extinct lobe finned fish

-diphycercal: extant love finned fish

-homocercal: ray finned fish

107
Q

Australian lungfish

A

Most similar species to ancestral lobe-fins: lobe-like fins and thicker scales than other lungfishes

-water breathing: rely on gills for oxygen
-lungs supplement gills during times of stress
-obligate air-breathers: drown without
-burrow in mud during dry season, secrete mucus to mix with mud to form hard cocoon.
-dormancy for up to 4 years
-reduced fins, but can still move ok land or underwater, using pelvic pins to lift body

108
Q

Coelocanth

A

-first known giant form from early Devonian
-thought to be extinct till 1938

-large:75cm to 2m long
-viviparous
-usually 250-300m deep
-rely on gills for respiration
-have a lung filled with fat as hydrostatic organ

109
Q

Extant sister group to tetrapods

A

Lungfish

110
Q

Tetrapodomorph

A

Important group of Sarcoptrrygii fish that have some characteristics also found in tetrapods. Includes Eusthenopteron and Tiktaalik

-choanae: internal nostrils that conenct external nostrils to pharynx
-bones homologous to tetrapods in arms
-dorsal-ventral flattened heads with nostril on dorsal surface in some like tetrapods

111
Q

Tetramorph fishes were extinct by the _______

A

Early Permian

112
Q

Actinopterygii 2 groups

A
  1. Relic groups- sturgeon, bichirs, bowfins: Cladistia and Chondrostei
  2. Air-breathing fishes
113
Q

Cladistia chatacterisitcs

A

Bichirs and reedfishes

-freshwater fish from Africa
-many “finlets” on dorsal surface
-armoured with ganoid scales (thick, diamond shape, interlocking)
-come to surface to gulp air; have lungs

114
Q

Chondrostei characteristics

A

Sturgeon and paddlefishes

-anadromous or freshwater, NH
-primarily cartilaginous skeleton
-dermal scutes (Armor-like scales) on back
-certain similarities to teleosts evolved independently: swim bladder, no lung, jaw not fused to cranium

115
Q

Sturgeons

A

-Largest freshwater fish
-benthic (bottom) cruiser
-highly protrusile mouth oriented downward, suction feeder (no terrh$

116
Q

Sturgeon life history

A
  1. Large size, slow growth, long life
  2. Mature 15-25years
    -lifespan 50-80 years

-high fecundity and small eggs
-spawn in rivers, no parental care

117
Q

Sturgeon conservation

A
  1. Overfishing since 1880-1900’s
    -have not recovered and still poached
  2. Hydropower dams alter habitats and interior travel corridors and impact egg survival and larvae
118
Q

The Devonian had which fish groups

A

Ostracoderms, placoderms, Chondricthyes, sarcopterugians, and actinopergii (ray finned fishes)

119
Q

Teleosts
-how many species
-habitat

A

> 30,000 species - making up 96% of all livi mg fish species

Worldwide, in all aquatic habitats

120
Q

Earliest repository fossil

When did Euteleosts appear

First tee lost appeared when

A

From the Triassic (Mesozoic)

100mya

200mya

121
Q

Basic trends in the ray-finned fishes and teleosts

A
  1. Heavy dermal armour replaced by light, thin flexible cycloid and ctenoid scales, allowing for increased mobility
  2. Homocercal tail allowing greater speed and buoyancy
  3. Swim bladder shifted from primarily respiratory to buoyancy in function
  4. Fins changed to provide greater mobility and to serve a variety of functions: braking, streamlining, social communication, camouflage, protection. Pectoral find moved to dorsal, pelvic fins moved more anterior.
  5. The use changed to enable increase suctioning and jaw protrusion to obtain food
122
Q

The larger the fish, the ______ they swim

Fast swimming species are _____ flexible

A

Faster

Less and limit undulation to caudal region

123
Q

How do swim ballers increase hearing sensitivity

A

-swim bladder amplified sound, increases hearing range (frequency) and amplitude. Teleosts can hear more than sharks or rays.

-some teleost groups improve sensitivity with a physical connection that conducts sounds directly from the swim bladder to the inner ear

124
Q

Ostariophysi and hearing

A

Catfishes, carps, minnows and more

-80% fresh water species, 25-30% of all fishes
-small bones (weberian ossicles, modified vertebral elements) transmit sound form swim bladder to ear.

Enables them to heat up to 4000hz, sharks can only heat up to 1000hz

125
Q

Swim bladder vs lungs of fishes

A

Swim bladder:
-primarily function in buoyancy
-enhanced hearing, especially when physically connected to inner ear
-may function in respiration in a small number of fishes

Lungs:
-primarily function in respiration
-have more surface area and are more vascularized (more blood supply)
-lungs appeared in fishes long before tetrapods invaded land
-secondary functions: buoyancy, possible hearing

126
Q

Swim bladders and neutral buoyancy

A

-Swim bladder is the most efficient flotation device. Neutral buoyancy means that find do not have to provide lift.
-mechanisms to adjust volume of gas entering or leaving bladder as fish moved up or down to maintain neutral buoyancy.
-greater pressure at depth reduced volume of gas in bladder; obtain more oxygen from blood via gas gland
-as ascending, has expands so expel gas from bladder (either to gut or to blood then gills)

127
Q

_________ is extremely well developed in teleosts

A

Jaw protrusion: mobility of upper jaw elements (premaxilla and maxilla) that border mouth enables jaw margins to extend forward.

Membrane of skin closed gap, increased effectiveness of suction and prey capture

128
Q

Similar to sharks, teleosts have developed the ability to move the ______________ independently of the mouth so as to protrude their jaws forward

A

Upper jaw

129
Q

Suction feeding

A

Rapid expansion of pro tan hail cavity (mouth and gill) creates negative pressure, drawing in water and prey

Enabled by jaw protustion

130
Q

Freshwater drum teeth

A

-incisor like anterior teeth on dentary for nipping prey off substrates
-pharyngeal teeth for shredding prey or crushing mollusk shells: shaped like rounded molars.

131
Q

Most teleosts have _____ sets of jaws

A

2 sets

Oral jaws used to capture and manipulate prey

Pharyngeal jaws at back of the throat to process food and love it from the mouth to the stomach

132
Q

Moray eels jaws

A

Mooray eels extend pharyngeal jaws into the oral cavity to grasp prey struggling in the eels mouth

133
Q

Temperature regulation and endothermy in fish

A

-body heat rapidly lost to water, especially with water running over blood vessels in the gills
-most fished have body temperature similar to water temperature. They depend on the external environment to regulate their temperature (ectothermy)

Some large marine species keep certain body areas warmer than water: swimming muscles, visceral organs like the heart, brain and eyes: blue finned tuna, mackerel sharks, mackerels = regional heterothermy

134
Q

How do bluefin tuna keep their swimming muscles warm?

A

Elaborate network of small blood vessels called retia in the swimming muscles, close to the vertebrae. Muscular activity wants the red muscle and the retia retains the heat in that location, so that it does not disperse to more distal parts of the body.

Keep muscles 12° warmer

Retia is example of counter current heat exchanger mechanism that conducts heat from vessels carrying blood leaving the muscle to vessels carrying blood to the muscles

135
Q

Why regional heterothermy?

A

Warmer body temperatures enhances swimming speed, sustained performance, nervous system activity

136
Q

Whole body endothermy

A

The Opah or mood shaped fish has whole body endothermy. Mains stable body temperature as it moved from waters surface to deep, cold waters. It uses pectoral find to propel itself and these muscles produce heat, and the muscles insulate the heat by a layer of fat that is 1cm thick.

Has retia inside the hill arches that isolate the respiratory surfaces of gills from the rest of the body, which reduced the loss of heat that normally happens when water flows over the gills.

137
Q

Most common developmental type in teleosts

What life history

A

Oviparous (97%)
-larval stage with young carrying yolk sac

R-selected life history

138
Q

Variation within teleosts of egg laying

A
  1. Marine eggs in the open ocean (pelagic)
    -smaller eggs, that are buoyant and released into open ocean (broadcast spawning)
  2. Marine: near shore and benthic species lay sticky eggs that adhere to weed or gravel on the sea bed
  3. Freshwater species: more likely to deposit eggs that are larger and are attached to weeds or stones. Some are laid in nests or brooded. Non-floating eggs are better suited to freshwater to avoid drifting downstream. Parental care more common this way too.
139
Q

Teleost development

A

-short incubation period followed by larval stage with young incompletely developed and carrying yolks sac
-metamorphosis: contrasts with cartilaginous fishes with no larval stage

140
Q

Catadromous bs anadromous life cycle

Which are eels

A

Spends most of its time in freshwater and migrate to sea to spawn (eels)

Spends most time in ocean and migrate to fresh water to spawn

141
Q

Eel stages

A

Leaf shaped eel larvae are borne at sea and in depths of the ocean. They slowly increase in size until metamorphosing into a transparent, glassy form called glass eel, which usually occurs as they start to migrate back to freshwater. The glass eel develops pigmentation and is then known as the elver.

Larvae in ocean for <1 year, in freshwater for 6-10 years

142
Q

Sexual fate is ______ in teleosts, and is influenced by _______ and _____\

A

Plastic- only 10% of fish have sex choir moms similar to humans (XX XY). Have autosomes that can influence phenotypic sex.

Genes and environmental and social conditions

143
Q

Sex determination of teleosts
-environmental factors

A
  1. Temperature: high temps produce physiological males from genetic females
  2. Pollutants: Endocrine disrupters influence physiological processes that affect development of gonads and sexual phenotype. - estrogen in lake feminized genetic males, resulting in decline in populations.

Many fish can switch sex during the embryonic stage

144
Q

Hermaphodites

Synchronous hermaphroditism

A

Presence of male and female organs on same individual

Male and female reproductive parts mature together (Tripod fish)
-self-fertilization does not occur
-potential of fertilizing two batches of eggs when encountering a mate

145
Q

Sequential hermaphroditism and types

A

Individual is either male or female early in life with potential to change to female or male later in life (physically, behaviourally and even neurologically)

Female first: Protogyny

Male first: Protandry

146
Q

Protogyny example and benefit

A

-blue head wrasse

Fish reproduce in the open ocean as broadcast spawners. So both males and females eject eggs and sperm into ocean. A dominant male defends mating territory and mates with 40-100 females a day. if dominant blue headed male dies, either a small male or female will grow and change colour to replace it. It can take only a week.

Males in open ocean habitat benefit more by being large

147
Q

Protandy example and benefit

A

Anemone-fish (clown fish)

Live in ocean ocean but spend lives in corals and live close to sessile invertebrate animals called anemone where they deposit and fertilize their eggs. They are monogamous. Male tends to eggs while larger female monitors and defends territory. If female dies, breeding male grows and develops female gonads to replace the breeding female. An immature fish will then develop into a mature male and partner with the female.

One male, regardless of size has plenty of Speke to fertilize the eggs of one female, so there is no advantage to being a large male. But larger female can produce more eggs than small female.

148
Q

Parental care of fishes

What is typical of pelagic and freshwater fish

A

Pelagic-no parental care for broadcast spawning

Care more common in fresh water fishes or fishes living near shore

149
Q

What percent of fishes have parental care?

What sex typically does parental care

A

30% of 500 fish families

Male care: 50%
Female care: 30%
Biparental care: 20%

150
Q

______ most likely to care when fertilization is external

______ most likely to care when fertilization is internal

A

Males

Females

151
Q

Forms of fish parental care

A

-Aerating and cleaning eggs
-Brooding (carrying eggs or young in mouth of pouches)
-post-hatching care (defence and food)

152
Q

Stickleback males care

A

Males build nest with dome and tunnel. Court females with dance. If successful, female lays eggs in tunnel, male then chases her away and other males away. Guards and aerate eggs (7-8 days). Protects and keep hound together after hatching (3 days)

153
Q

One exception to males caring for young with internal fertilization

A

-Make sea horses carry eggs and larval young in brood pouch or on abdomen or tail.
-expel larval young after 2-4 weeks.

154
Q

Tetrapods

A

Vertebrates having four limbs or descending from vertebrates having four limbs (snakes, whales birds)
-includes amphibians and amniotes

155
Q

Tetrapods needed support against gravity and increased location on, resulting in a _______

A

Skeleton-relatively rigid band strong
Skeletons and muscles of limbs and feet modified to push against substrate (ground)

156
Q

Forelimb of acanthostega

A

-humerus, radius and ulna, carpels (wrist bones), and phalanges
-8 digits

Hind limbs did not articulate with the pelvis

157
Q

Icthyostega adaptations to life on land not seen in acanthostega

A

-limbs were fully formed including a pelvis articulated with the vertebral column and it’s vertebral column was more robust.
-stronger backbone
-shoulder and hip girdles
-muscles support body in air, and muscles to raise head
-ear structure modified to detect airborne sounds

Forelimb with humerus, radius and ulna, carpels and phalanges

Hindlimb with genus, tibia and fibula, tarsal (ankle bones) and phalanges.

158
Q

Eusthenopteron (385 mya) homologous bones to terrapods

Tiktaalik (375mya) homologous strucures to tetrapods

A

-Humerus, radius and ulna
-could probably use “walking” find to pull itself along substrate
-had lungs

-intermediate between lobe-finned fishes and terrapods
-probably my used limbs to support body while placing snout above water to breathe air in shallow water

159
Q

Double circulation system

Who has it?

A

-made possible by separation of right and left chambers of atrium and ventricle that separate oxygen-rich and oxygen-poor blood

Adult amphibians have incomplete separation of chambers. There is a permanently divided atrium but the centuries are temporarily separated.

True separation for turtles and most lizards.

Mammals and birds have permanently divided structures

Applies to all terrapods (amphibians and amniotes)

160
Q

Double circulation system pathways

A

Blood passes through the heart twice, for there are two distinct routes of circulation

  1. Pulmonary circulation: deoxygenated blood is pumped from heart to lungs; oxygenated blood results to the heart.
  2. Systemic circulation: oxygenated blood is pumped from the heart around the body. Blood returns to the heart as deoxygenated.
161
Q

Fish have what type of circulation

A

Single circuit

Blood passes through the heart only once during full route around the body

Deoxygenated blood is oxygenated as it passes through the gill capillaries

162
Q

Limitations of single circuit system

A

Blood flow and pressure falls when blood leaves a fish’s gills

Works for fish, but would not work on land

163
Q

Advantages of double circuit circulatory system

A

-chambers separate oxygen rich form oxygen poor blood-> ensures blood is rich in oxygen when reaching tissues, muscles and organs

-blood is pressurized twice for each cycle around blood system-> higher blood pressure and increased rate of blood flow.

Allows blood to be pumped against gravity, enables larger body size, and higher blood flow needed for higher metabolic rates and endothermy.

164
Q

Modifications to respiration in tetrapods

A

Modifications to lungs to increase surface area and vascularization (capillary network)

Internal nares (choanae) connect to pharynx to enable animal to love air from nares to lungs for respiration

165
Q

Olfaction in tetrapods vs fish

A

Nasal cavity lined with olfactory epithelium that contains olfactory receptors. With each breath, air can pass over olfactory epithelium.

Have a pouch with olfactory epithelium. Water enters and flowed over this surface then exits. Fish smell after water enters pouch and contacts olfactory epithelium. With few exceptions, nostrils of fish do not connect to the mouth or Pharynx.

166
Q

Lateral line system transition to land

A

Aquatic vertebrates have a lateral line system (fishes, larval and permanently aquatic amphibians)
-movement of water molecules directly stimulates the hair cells of the lateral line system
-amphibians lose the lateral line system after metamorphosis
-air is not dense enough to transmit information form motion or sound

167
Q

Hearing in water vs terrestrial

A

Density of animal tissue is similar to water

Sound readily passes through animal tissues, stimulating hair cells of inner ear.

Air is not dense enough for transmission of sound or motion. Not lateral line system in terrestrial animals.

168
Q

Hearing in terrestrial animals requires a ________

A

Middle ear: tympanic membrane (ear drum) and stapes (columella bone) amplify and transmit vibrations to inner ear, which discriminates frequency (pitch) and intensity (amplitude)

169
Q

Vision land adaptations

A
  • light transmits with less disturbances in air than in water, so is more effective for distance perception
    -cornea focuses light on retina
    -tetrapod lens is flexible and becomes more rounded to focus on closer objects
    -eyelids and lacrimal gland protects and wash eyes which is necessary since eye has contact with air rather than water
170
Q

Nictitating eyelid

A

Transparent eyelid to protect and lubricate eye, enabling vision found in terrestrial animals, sharks

Readily viable in amphibians, reptiles and birds

171
Q

Parietal eye or pineal eye

A

-photoreceptive organ associated with pineal gland. Important in regulating day/night or seasonal cycles through release of melatonin. Role in thermoregulation for animals that rely on ectothermic temperature regulation

-some fishes have this too like lamprey
-mammals do not have parietal eye but do have pineal gland

172
Q

Sensory disadvantages and advantages on air

A

Dis-air not dense enough to easily stimulate mechanical receptors or conduct electricity

Ad-air has increased light for vision