Chapter 12
1. A polymorphic locus is one that
a) codes for more than one protein.
b) codes for both protein and lipid.
c) occurs in a population as more than one allele.
d) occurs on more than one chromosome.
e) can cause more than one phenotype in an individual, depending on the environment.
Answer: C
2. Rates of gene flow can be estimated from similarity in allele frequencies among
populations.
Answer: T
3. Which of the following observations can be explained by the energetic limitation of an
organism’s total reproductive effort?
a) Darter diversity is very high in the Ozark Highlands.
b) Darters that lay many eggs lay smaller eggs, on average.
c) Seed size in plants varies over at least 10 orders of magnitude.
d) Seed size in plants depends in part on the plant’s seed dispersal mechanism.
e) More than one of the above.
Answer: B
4. The number of eggs laid by a female is called her
a) fertility.
b) gonadosomatic index.
c) growth form.
d) rotundity.
e) fecundity.
Answer: E
5. Seeds bearing eliasomes are likely to be dispersed by
a) ants.
b) wind.
c) water.
d) birds.
e) scatterhoarding mammals.
Answer: A
6. A “forb” is a(n)
a) fish species living in the open ocean.
b) bird species having offspring independent at a young age.
c) plant species with woody tissue.
d) grass or sedge.
e) herbaceous, but non-graminoid, plant species.
Answer: E
7. Which of the following environments for germinating seed is most likely to favor a
plant species that makes many small seeds, compared to one that makes fewer larger
seeds?
a) nutrient limitation
b) competition from established plants
c) shade
d) deep burial in soil
e) disturbance
Answer: E
8. Because natural selection has shaped fish life histories,
a) fish species with high adult mortality tend to mature at a younger age.
b) fish species with high adult mortality tend to mature at an older age.
c) fish species with high adult mortality tend to invest relatively large amounts of energy
in reproduction.
d) Both fish species with high adult mortality tend to mature at a younger age and fish
species with high adult mortality tend to invest relatively large amounts of energy in
reproduction are true.
e) Both fish species with high adult mortality tend to mature at an older age and fish
species with high adult mortality tend to invest relatively large amounts of energy in
reproduction are true.
Answer: D
9. Life histories typical of r-selection are most likely to evolve where species populations
are near carrying capacity much of the time.
Answer: F
10. The “K” in “K-selection” comes from the
a) ecologist who coined it, Astrid Kodric-Brown.
b) shape of the age-vs-mortality-rate plot for K-selected species.
c) “K” in the logistic growth equation.
d) Greek letter “kappa,” symbolizing fecundity.
e) none of the above
Answer: C
11. Which of the following is NOT a characteristic favored by K-selection?
a) low intrinsic rate of increase
b) late reproduction
c) many, small offspring
d) repeated bouts of reproduction
e) strong competitive ability
Answer: C
12. Grime’s classification of plant life histories focuses attention on
a) stress and disturbance.
b) stress and nutrient availability.
c) disturbance and gene flow.
d) disturbance and plant species diversity.
e) r- vs. K-selection.
Answer: A
13. Fill in the blank: In Grime’s classification, a plant species adapted to highly disturbed
environments is called a ____________ species.
Answer: ruderal
14. In Grime’s classification, stress-tolerant plants
a) live under conditions of high stress and also high disturbance.
b) grow rapidly.
c) are very palatable to herbivores.
d) conserve nutrients and water.
e) all of the above
Answer: D
15. Among fish species, an “opportunistic” life history is characterized by
a) high juvenile survival, large numbers of offspring, and early maturity.
b) high juvenile survival, large numbers of offspring, and late maturity.
c) low juvenile survival, low number of offspring, and early maturity.
d) traits that maximize colonizing ability for environments that do not vary much in time
or space.
e) traits that maximize colonizing ability for environments that are very stressful.
Answer: C
16. A fish maturing late with large body size and producing many small offspring would
be said to have a(n)
a) periodic life history.
b) opportunistic life history.
c) equilibrium life history.
d) precocial life history.
e) stress-tolerant life history.
Answer: A
17. Bird species whose offspring are born helpless and depending on parental care are
said to be _____________.
Answer: altricial
18. Which relationship correctly compares birds, mammals, and fish with respect to
relative reproductive lifespan (reproductive period compared to time to maturity)?
a) birds > mammals > fish
b) mammals > birds > fish
c) fish > mammals > birds
d) mammals > fish > birds
e) all three groups have similar values
Answer: A
19. As a fraction of adult mass, the mass of offspring at independence tends to be largest
in
a) mammals.
b) altricial birds.
c) fish.
d) both mammals and fish.
e) All three groups have similar values.
Answer: B
20. “Riparian” refers to plant communities occurring
a) in the tropics.
b) at high altitudes.
c) along the edges of deserts.
d) in permanently flooded areas.
e) in transitions between riverbanks and upland areas.
Answer: E
21. Which of the following is NOT true of riparian plant communities?
a) plant species adapted to frequent disturbance by flooding
b) plant species dependent on flooding often dominant
c) low species diversity, compared to surrounding terrestrial communities
d) high population densities, compared to surrounding terrestrial communities
e) seriously impacted by human activities
Answer: C
22. The study of the relationship between climate and the timing of ecological events is
called
a) ecology.
b) phenology.
c) oenology.
d) climatology.
e) life history theory.
Answer: B
23. Which statement about the impact of dams on cottonwood forests is false?
a) Damming reduces growth of established cottonwoods downstream.
b) Damming increases mortality of established cottonwoods downstream.
c) By reducing flooding downstream, damming improves cottonwood seed germination.
d) The timing of water release from a dam can greatly affect cottonwood seed
germination.
e) Careful management of flow through dams can greatly reduce harmful impacts on
cottonwoods downstream.
Answer: C