53 Chapter 53: Community Ecology 433
4. Which of the following is not an example of 9. When one species was removed from a tidepool,
coevolution? the species richness became significantly reduced.
a. adaptations of flowers and their exclusive pol The removed species was probably
linators a. a strong competitor.
b. passion-flower vines and the butterfly b. a potent parasite.
Helicon ins C. a resource partitioner.
c. a parasite that is specific for one host d. a keystone species.
d. a brood parasite’s eggs that mimic the host e. the species with the highest relative abun
species’ eggs dance.
e. aposematic coloration of monarch butterflies
and predators that learn not to eat them 10. A highly successful parasite
a. will not harm its host.
5. Through resource partitioning, b. may benefit its host.
a. two species can compete for the same prey c. will be able to feed without killing its host.
item. d. will kill its host fairly rapidly.
b. slight variations in niche allow closely related e. will have coevolved into a commensalistic
species to coexist in the same habitat. interaction with its host.
c. two species can share the same realized niche
in a habitat. 11. The most important factor(s) in determining com
d. competitive exclusion results in the success of munity structure
the superior species. a. may change from one community to another,
e. two species undergo character displacement b. is predation.
that allows them to compete. C. is competition.
d. is mutualism.
6. A species may be restricted to a particular range e. are structural diversity and environmental
because patchiness.
a. it cannot tolerate environmental conditions
outside that range. 12. During succession, inhibition
b. it has never dispersed beyond that range. a. may prevent the achievement of a climax com
c. it has retracted from a former range due to munity.
local extinctions. b. is evidence for the equilibrial theory of succes
d. it would outcompete native species if it were sion.
transplanted to their habitat. c. is one of the factors that determines the most
e. a, b, and c are all true. tolerant species in an area.
d. may interfere with the successful colonization
7. Aposematic coloring is most commonly found in of other species.
a. prey whose body morphology is cryptic. e. may involve changes in soil pH or accelerated
b. predators who are able to sequester toxic plant accumulation of humus.
compounds in their bodies.
c. prey species that have chemical defenses. 13. According to the nonequilibrial model of succes
d. good-tasting prey that evolve to look like each sion,
other. a. chance events such as dispersal and disturb
e. prey species that are camouflaged to match ance play major roles in succession, and species
their environment. composition remains in flux.
b. species diversity is greatest in the climax com
8. A palatable (good-tasting) prey species may munity.
defend against predation by c. when succession reaches a climax community,
a. Müllerian mimicry. only extinctions make room for new colonists.
b. Batesian mimicry. d. the communities with the greatest diversity
c. secondary compounds. have the greatest resistance to change.
d. aposematic coloration. e. early colonizers are r-selected and later com
e. either a or b. munity members are K-selected.
434 Unit Eight: Ecology
14. An island that is small and far from the mainland, 16. Two species of finches have similar beak sizes and
as compared to a large island close to the main eat a similar selection of foods. Where their
land, ranges overlap, however, the beak of one species
a. would be expected to have a lower species is found to be larger than that of the other. What
diversity. is the ecological explanation for these different
b. would be expected to be in an earlier succes beak sizes?
sional stage. a. coevolution
c. would have a smaller species diversity but a b. competitive exclusion
larger abundance of organisms. c. exploitative competition
d. would have a higher rate of colonization but a d. interference competition
higher rate of extinction. e. character displacement
e. would have a lower rate of colonization and a 17. Two species of Anolis lizards are often found
lower rate of extinction. perched and feeding in the same trees. Species I is
usually found in the upper and outer branches,
15. The island recolonization experiment of
species II usually occupies shady inner branches.
Simberloff and Wilson showed that
An ecologist removes one or the other species and
a. species diversity returns very slowly to an
observes changes in the remaining species’s dis
island after a disturbance.
tribution in the trees. Species I is found through
b. the species diversity was highest when distur
out the branches of trees in which it is now the
bances were intermediate in frequency and
sole occupant. Species II is still found in the shady
severity.
interior when it is the sole occupant. What does
c. whereas approximately the same numbers of
the ecologist conclude from these experimental
species of arthropods returned to each island,
results?
the species composition was different, indicat
a. Species I is the better competitor.
ing the importance of chance events.
b. Species I is not a shade-tolerant species.
d. islands closest to the mainland had the greatest
numbers of arthropods recolonize, and their c. The fundamental niche of species II is identical
to its realized niche.
community composition and diversity were
d. The fundamental niche of species II is larger
the same as prior to fumigation.
than its realized niche.
e. the largest islands had the greatest species rich
e. The fundamental niche of species I is identical
ness but the least species diversity.
to its realized niche.
TEST YOUR KNOWLEDGE species A does not successfully colonize the area.
What might you conclude from these results?
a. Both species A and species B are limited to
MULTIPLE CHOICE: Choose the one best answer.
their range by abiotic factors.
1. Which of the following is not part of Gleason’s b. Species A is limited to its range by competition
individualistic concept of communities? and species B is limited by abiotic factors.
a. Communities are chance collections of species c. Both species are limited to their range by com
that are in the same area because of similar petition.
environmental requirements. d. Species A is limited to its range by abiotic fac
b. There should be no distinct boundaries tors and species B is limited to its range
between communities. because it cannot compete with species A.
c. The consistent composition of a community is e. Species B is K-selected and species A is r-select
based on interactions that cause it to function ed.
as an integrated unit.
3. The species richness of a community refers to
d. Species are distributed independently along
a. the relative numbers of individuals in each
environmental gradients. /
species.
e. Most plant communities studied meet the pre
b. the number of different species found in a com
dictions made by this concept.
munity.
2. Two species, A and B, occupy adjoining environ c. the feeding relationships or trophic structure
mental patches that differ in several abiotic fac within the community.
tors. When species A is experimentally removed d. the species diversity that is characteristic of
from a portion of its patch, species B colonizes the that community.
vacated area and thrives. When species B is exper e. the ability to persist through disturbances.
imentally removed from a portion of its patch,
Chapter 54: Ecosystems 441
3. In an ecosystem, c. The pyramid of productivity of some aquatic
a. energy is recycled through the trophic struc ecosystems is inverted because of the large
ture. zooplankton primary-consumer level.
b. energy is usually captured from sunlight by d. Eating grain-fed beef is an inefficient means of
primary producers, passed to secondary pro obtaining the energy trapped by photosynthe
ducers in the form of organic compounds, and sis.
lost to detritivores in the form of heat. e. A pyramid of numbers is usually the same
c. chemicals are recycled between the biotic and shape as a pyramid of productivity.
abiotic sectors, whereas energy makes a one-
way trip through the food web. 9. Biogeochemical cycles are global for elements
d. there is a continuous process by which energy a. that are found in the atmosphere.
is lost as heat, and chemical elements leave the b. that are found mainly in the soil.
ecosystem through runoff. c. such as carbon, nitrogen, and phosphorus.
e. a food chain shows that all trophic levels may d. that are dissolved in water.
feed off each other. e. in the nonavailable reservoirs.
4. Primary productivity 10. Which of these processes is incorrectly paired with
a. is equal to the standing crop of an ecosystem. its description?
b. is greatest in freshwater ecosystems. a. nitrification—oxidation of ammonium in the
c. is the rate of conversion of light to chemical soil to nitrite and nitrate
energy in an ecosystem. b. nitrogen fixation—reduction of atmospheric
d. is inverted in some aquatic ecosystems. nitrogen into ammonia
e. is all of the above. c. denitrification—removal of nitrogen from
5. The open ocean and tropical rain forest are the organic compounds
two largest contributors to Earth’s net primary d. ammonification—decomposition of organic
productivity because compounds into ammonia
a. both have high rates of net primary productivi e. evaporation of ammonia—loss of ammonia to
tv. the atmosphere from nonacidic soils
b. both cover huge surface areas of the Earth. 11. Carbon cycles relatively rapidly except when it is
c. nutrients cycle fastest in these two ecosystems. a. dissolved in freshwater ecosystems.
d. the ocean covers a huge surface area and the
b. released by respiration.
tropical rain forest has a high rate of productiv
c. converted into sugars.
ity.
d. stored in petroleum, coal, or wood.
e. both a and b are correct.
e. part of the bicarbonate reservoir in oceans.
6. Productivity in terrestrial ecosystems is affected by
12. The ecological timescale of phosphorus cycling
a. temperature.
b. light intensity. involves
c. availability of nutrients. a. the uptake of phosphate from drinking water.
b. the weathering of rock to add P0
3 to the soil.
4
d. availability of water.
c. sedimentation to form rocks in the sea bed.
e. all of the above.
d. the incorporation of phosphorus into organ
7. Secondary productivity isms that become fossils.
a. is measured by the standing crop. e. bothaandb.
b. is the rate of biomass production in consumers.
c. is greater than primary productivity. 13. Which of the following was not shown by the
d. is 10% less than primary productivity. Hubbard Brook Forest study?
e. is the gross primary productivity minus the a. Most minerals recycle within a forest ecosys
energy used for respiration. tem.
b. Deforestation results in a large increase in
8. Which of the following is not true of a pyramid of water runoff.
productivity? c. Mineral losses from a valley were great follow
a. Only about 1O’Y
0 of the energy in one trophic ing deforestation.
level is passed into the next level. d. Nitrate was the mineral that showed the great
b. Because of the loss of energy at each trophic est loss.
level, most food chains are limited to three to e. Acid rain increased as a result of deforestation.
five steps.
442 Unit Eight: Ecologi,
14. The finding of harmful levels of DDT in grebes 16. What do primary producers have available to
(fish-eating birds) in Clear Lake, California, fol convert into biomass?
lowing years of trying to eliminate bothersome a. 10% of secondary productivity
gnat populations, is an example of b. energy used for respiration
a. eutrophication. c. gross primary productivity
b. biological magnification. d. net primary productivity
c. the biomass pyramid. e. 100% of the solar energy they absorb
d. chemical cycling.
17. Which of the following trophic levels would have
e. increasing resistance to pesticides.
the largest numbers of individuals?
15. The greenhouse effect a. primary producers
a. could change global weather and lead to the b. omnivores
flooding of coastal areas. C. primary consumers
b. could result in more C4 plants in plant commu d. opportunistic feeders
nities that were previously dominated by C 3 e. tertiary consumers
plants. 18. A serious effect of the thinning of the ozone layer
c. causes an increase in temperature when CO 2 is
absorbs more sunlight entering the atmos a. a reduction in species diversity.
phere. b. global warming.
d. could increase precipitation in central conti c. acid precipitation.
nental areas. d. an increase in UV radiation reaching Earth,
e. could do all of the above.
5v e. cultural eutrophication.
TEST YOUR KNOWLEDGE
MULTIPLE CHOICE: Choose tile one best anslz’t’r.
1. Which of the following organisms and trophic
levels is mismatched?
a. algae—producer
b. phy toplan kton—primary consumer
c. fungi—detritivore
d. bobcat—secondary consumer
e. eagle—tertiary or quaternary consumer
2. Chemosynthetic bacteria found around deep-sea
vents are examples of
a. producers.
b. decomposers.
c. chemical cycling.
d. secondary productivity.
e. upweliing thit make uitrieuts available.
Answers to Test Your Knowledge
Multiple Choice:
53 Answers to Test Your Knowledge
Multiple Choice:
Lc 5.b 9.d 13.a 17.c Lb 5.d 9.a D.c. 17.a
2.d 6.e 1O.c 14.a La 6.e 1O.c 14.b 18.d
3.b 7.c ita 15.c 3.C 7.b 11.d 15.a
4.e Sb 12.d 16.e S.c fl.b 16.d
Answers to Test Your Knowledge
53 .nswers to Test Your Knowledge
Multiple Choice: Multiple Choice:
Lc 5.b 9.d 13.a 17.c Lb 5.d 9.a D.c 17.a
Ld 6.e 1O.c 14.a La 6.e lO.c 14.b 18.d
3.b 7.c lLa 15.c 3.c 7.b l1.d 15.a
4.e 8.b ILd 16.e 4.c S.c 12.b 16.4
Answers to Test Your Knowledge
Multiple Choice:
53 .nswen to Test Your Knowledge
Multiple Choice:
Lc 5.b 9.d 13.a 17.c Lb 5.d 9.a 13.e. l7.a
Ld 6.e 1O.c 14.a La 6.e 1O.c ltb 18.d
3.b 7.c lLa 15.c 3.c 7.b 11.d lS.a
4.e 8.b iLd 16.e 4.c S.c lLb 16.d
Answers to Test Your Knowledge
Answers to Test Your
owledge
53
Multiple Choice:
Multiple Choice: 9. a 13. e 17. a
1. b 5.
9.d J3.a 17.c b.c 14.b 18.4
Lc 5.b La 6.e
b.c 14.a 7.b ii.d 15.a
Ld 6.e 3.c
•11.a 15.c S.c lLb 16.d
3.b 7.c 4.c
.b itd 16.e
4.e
nswers to Test Your Knowledge
Answers to Test Your Knowledge 53
Multiple Choice:
Multiple Choice: 17. a
1. b 5. d 9. a 13. e.
9.d 13.a b7.c m.d
b.c 5.b La 6.e 1O.c b4.b
6.e b.c b4.a 7.b ii.d b5.a
Ld
7.c bb.a b5.c S.C lLb b6.d
3.b
8.b ILd 16.e
4.e
