Review Questions for Test 3 – Ichthyology 2008
Breeding Strategies
1. Explain the difference between pelagic and demersal eggs. Where does each go in the
water column? What are the consequences for gene flow among populations? Give an
example of a pelagic and a demersal spawner.
2. Explain the difference iteroparity and semelparity. Are capelin iteroparous or
semelparous? How did the capelin spawn? List 2-3 groups of fish that are semelparous.
List 2-3 groups of fish that are iteroparous.
3. Distinguish between promiscuous, polyandrous, polygynous, and monogomous
breeding systems. List 2 groups of fish that display each breeding type.
4. Distinguish between simultaneous, protandrous, and protogynous hermaphrodites and
given an example of each. What is the “size advantage model” for the evolution of sex
change in fishes? (page 351) When does it predict protandrous hermaphroditism and
when does it predict protogynous hermaphoriditism?
5. What is the difference between primary and secondary sexual traits? (page 353). Give
examples of each.
6. What is a “spawning rush” and why do some species do this?
7. How do Corydoras fertilize their eggs? (page 357).
8. Accord to the data presented by Mendelson, what evolves faster - prezygotic or postzygotic isolation? What is the evidence for this?
9. What has a larger influence on reproductive isolation between E. luteovinctum and E.
hopkinsi - behavioral, gametic, or postzygotic isolation? What is the evidence for this?
Scorpaeniformes
10. What character unites the Scorpaeniformes? How old is the oldest documented
teleost? What type of fish was the oldest documented teleost? Explain the reproductive
biology of Scorpanidae (Scorpionfishes).
11. What is unique about the sea robins and flying gurnards? Do flying gurnards really
fly?
12. Which members of Scorpaneiformes can be found in freshwater?
13. Why have swamp eels had a negative effect on areas where they have been
introduced? Why were they introduced? Give 3 reasons why swamp eels are so difficult
to eradicate. How many species of swamp eel have been introduced into the US? Has
there just been a single introduction or have there been multiple introductions? What is
the evidence for this?
14. Describe the fin morphology of swamp eels.
Cold Tolerance in Antarctic Fishes
15. Why do fish in the Antarctic need an anti-freeze mechanism? Why don’t
marine invertebrates who are isosmotic with sea water need an anti-freeze
mechanism?
16. List the two barriers that keep Antarctic fauna separate from that in the Indian,
Atlantic, and Pacific Oceans. Why was the Antarctic fauna much more diverse
40 MYA?
17. Some teleosts can actually handle being super-cooled. The trick is to prevent
the formation of ice crystals in the fish. List the 3 main strategies by which
Antarctic fish can do this.
18. List the two ways that fish living in close approximation with ice avoid forming ice
crystals internally. How is the anti-freeze mechanism of the Notothenioids different from
the anti-freeze used by a car?
19. Where did AFGP arise from in Nototheniods? What is the evidence that the
evolution of AFGP played a role in the diversification of this group?
20. From which gene did AFGP arise from?
21. Arctic ods also have an AFGP. There are two possible ways this could have
happened. First, the common ancestor could have also possessed the AFGP gene.
Second, the gene could have evolved independently in the two different groups. Which
one is most likely? Provide 3 lines of evidence to support your answer.
Patterns in Illinois Fishes
22. How many species of freshwater fish are there in N.A. north of Mexico?
How
many occur east of the continental divide? What are some reasons for this?
23. Which 5 fish families account for the greatest number of species in the US?
In Illinois? Which is the area of highest fish diveresity in the US?
24. Give 5 reasons why general faunal surveys are informative.
25. List 4 “major” types of fish habitats in Illinois.
26. List 5 reasons for declines/extinctions in Illinois fishes. For each factor, list
one fish species that is affected. List 4 reasons why some fish species are
doing better now.
27. List 5 reasons why non-native fishes are introduced. For each one, give an
example.
28. Who was Stephen Forbes and who was Phil Smith, and what was their
contribution to Illinois Ichthyology?
Big Old Grab Bag of Fish including Stargazers, weeverfish, dragonets, clingfish, and
blennies
29. Describe the position of the pectoral and pelvic fins for the following groups:
stargazers, weeverfish, sanddivers, blennies, clingfish, dragonets. Which of these
fish have venom associated with spines? Where are these venomous spines
located.
30. Describe the mating systems of stargzers, blennies, clingfishes, and dragonets.
31. Describe the adaptations of stargazers and weeverfish that allow them to live
submerged in the sand.
32. Where do clingfish live and how does the morphology of their pelvic fins reflect
this?
33. Who are the sabre-toothed blennies and what do they eat? Describe their
strategy for eating.
Introduction to Life-Tables
34. A population of Aphredoderus sayanus starts out with 1000 newborn individuals.
At age 1, there are 200 animals left, at age 2 there are 100, at age 3 there are 20. At age 4
there are 2. At age 5 they are all dead. Reproduction begins at age 2. Females at age 2
produce an average of 10 eggs. At age 3, they produce 200 eggs. At age 4 they produce
250 eggs.
a. From this data, calculate the life-table including p(x), l(x), m(x), the product of
l(x)m(x), Ro, T, r, and λ. Define in words p(x), l(x), m(x), the product of l(x)m(x), Ro, T,
r, and λ.
b. Calculate the sensitivity and elasticity that results from a 10% increase to each
of the elements in the life-table. Make sure to do this for p(x). Note that the equations
are at the end of this word document.
c. Which elements have the biggest effects on λ? Which elements do you think
are most likely to be modifiable? Which ones can humans effect by alterations to
habitat? Which ones might be capable of responding to selection?
35. Book Question: Describe the trade-off between early versus late
maturation. Why does this occur?
36. Book Question: Describe the trade-off between egg number and egg
size. What are the benefits to having larger eggs?
Life-Tables & Salmon
Questions 37-39 refer to the matrix shown below from Kareiva et al.
37. What do these bars tell us? Which parameters were altered in the matrix? What
do these parameters mean? What is the conclusion for the fish?
38. What is the conclusion from this graph? What parameters in the matrix
were altered? What do these parameters correspond to?
39. What does this graph tell us about the important stages to manage?
Life-History, Fisheries, & Evolution – Conover & Munch paper
40. What recommendations do Conover & Munch make for increasing size of fish and
total harvest?
41. Which ones do you think seem most likely to have an effect?
42. What is the inherent conflict illuminated by Conover & Munch’s paper?
43. What is heritability?
44. What are the two main assumptions that people make when using basic life-table
analysis? Which of these assumptions are a problem for guppies? For silversides? For
salmon?
45. Based on Conover & Munch’s paper, what do you think will happen to a fish
population where only the large individuals are harvested? What do you think will
happen to a fish population where only the small individuals are
harvested?
46. Catching only the small individuals seems like a problem with modern trawls. Can
you think of a way around this?
47. What assumptions did we make in our simple life-table analysis?
48. What does it mean when we say that life-history parameters are density
dependent? What does it mean when we say that life-history parameters
are density-independent?
49. What does it mean when we say that life-history parameters have evolved?
50. Why do Conover and Munch make the following statement: “Moreover, the
genetic changes caused by selective harvest may be irreversible; cessation
of harvest does not guarantee reverse selection back to the original state.”
51. Conover & Munch selected on the smallest guys at a given age. How does this
compare with the guppy experiments? Is this what they did? Or did they do
something else?
52. (referring to the graph above) What treatments did Conover & Munch use?
53. (again referring to the graph above) Which treatments produced the largest harvest
& the largest sized fish? Why did this happen?
Fisheries & Marine Reserves
54. What three observations have led people to seek a “risk-averse” management
strategy in marine reserves?
55. List 5 ways that fisheries are damaging to fish populations. In theory, how would
marine reserves effect this?
56. List 3 ways that fisheries damage wild populations with non-intended takes. How
much of fishery mortality is estimated to be a consequence of by-catch?
57. What are our goals for marine reserves? What evidence is there that marine reserves
increase #s and biodiversity within the reserves? What evidence is there are spillover
effects?
58. List 4 different criteria for determining whether or not marine reserves are
“beneficial”. Which criteria do you think are likely to be upheld and which ones are
likely to not be true?
59. Can marine reserves result in a global λ > 1 for a species that is the target of
harvesting? What would have to be done to have λ > 1?
60. In your opinion, are marine reserves a good idea?
61. What types of species are most likely to benefit from marine reserves?
62. Where should marine reserves be located? How large should they be?
Tetraodontiformes & topminnow results
63. Why are the Tetraodontiformes considered to be the most divergent fishes away
from the basic Teleostean design?
64. In general, what’s unique about the type of food that animals in this group eat?
65. What kind of parental care do Triggerfish have? How do Triggerfish and filefish
use their “triggers” (or files)? How do these two groups differ?
66. Explain the unique features of boxfishes, puffers, and burrfish. How do they
each protect themselves from predation? Why is it a bad idea to cook pufferfish
for yourself? Describe some of the unique features of the ocean sunfish.
67. What differences did we find in age and size between lakes and streams in
the blackstripe topminnow? For both traits (age and size), list a few possible
factors that could account for these differences. Describe an experiment that
would test these.
68. Male topminnows have larger anal fins and larger dorsal fins than females.
List a couple of hypotheses as to why these differences have evolved. Describe an
experiment that would test these ideas.
Peroidei
69. What adaptations lead to so many species of darter?
70. How many species of Sander are in North America. Why?
71. What makes jacks and pompanos strong swimmers?
72. What is inquilinism? Which family is it common among?
73.What factors has the archer fish evolved to adjust its aim too?
74. What adaptations do the sea basses and groupers have for consuming mollusks?
75. For what reasons is the snapper fishery on a decline?
76. What type of prey items are typical for Micropterus salmoides?
79. How do you tell the difference between Micropterus salmoides, dolomieu, and
punctulatus?
Labroidei
80. What is the main hypothesis for Cichlid speciation and what is the reasoning behind
the accepted molecular clock?
81. What are the benefits that clownfish and anemone receive from their symbiotic
relationship?
82. Which families are protogynous hermaphrodites and which are protandrous
hermaphrodites?
83. What are some specific advantages to the damselfish gardening algae?
84. What is “Lekking”?
85. Why has the Nile Perch been introduced to the Lake Victoria region and what effect
does it have to native cichlid species?
86. What are the advantages and disadvantages to the two types of brooding.
87. What types of water bodies would you think tubular, disc and stream-lined cichlids
inhabit?
Scombroidei
88. What about the biology of tuna and other scombroids makes them vulnerable to
overexploitation? Why should we worry about declining tuna populations?
89. What advantage do endothermic Scombroids have over fish without endothermy? If
endothermy is so great, why not commit to it? That is, what advantage does regional
heterothermy have over complete endothermy?
90. What is Ram ventilation? Which fish groups can it be found? How does it help those
fishes to get oxygen?
91. Why do researchers think heater organs evolved multiple times in Scombroids? How
do heater organs differ from red muscle in the way heat is created?
92. Why do swordfishes like to jump from the ocean?
Gobioidei
93. What adaptations do gobies have for a benthic lifestyle?
94. Why are loach gobies considered the most primitive gobies?
95. Why is Gobiidae so speciose?
96. Why do experts think there may be lots of undiscovered species in Gobiidae?
97. Where is the round goby native to?
98. What role does the goby play in the shrimp goby/shrimp mutualism?
Pauly et al. paper
99. What pattern in fishing with respect to depth and time is being shown in this figure?
100. What does the “20/20” stand for?
Fish Taxa List
sand divers
sand lances
weeverfishes
stargazers
dragonets
clingfishes
blennies
Scorpaneiformes
rockfish
sculpin
lionfish
swampeel
mudskippers
shrimp goby
round goby
loach goby
mackerels
tunas
bonitos
swordfish
sailfin marlin
cutlassfishes
cichlids
surfperches
damselfishes
clownfishes
wrasses
parrotfish
largemouth bass
smallmouth bass
crappie
snapper
grouper
remora
we’ll leave the darters for the practical.
Ruffe
carangids
cardinal fishes
pearl fishes
archerfishes
American soles
tonguefishes
right eye flounders
halibut
triggerfishes
filefishes
boxfishes
pufferfishes
burrfish
ocean sunfish
Nototheniod
Equations you will be provided with for the test.
 

  xlx mx 

T 
R0
ln  R0 
T
r
 e
r
r  ln 
lx  p0 * p1 *... px 1
R0   lx mx