59)
The snail kite (Rostrhamus sociabilis) is a specialist that feeds on only one specific type of snail.
By comparison, the Mallard Duck (Anas platyrhynchos) is a generalist that feeds on diverse food
sources. Whereas the snail kite has a very limited range, the Mallard Duck has a very broad
range. The snail kite’s diet is an example of a(n)
A) limiting factor.
B) range of tolerance.
C) ecological niche.
D) habitat.
60) Which of the following would not be a limiting factor for a plant species?
A) soil phosphorus content
B) daily precipitation values
C) number of preadors
D) days below freezing
61) When a community is disturbed to the point that most or all of its species are eliminated, a
process called ________ occurs in which the area undergoes a series of changes in species
composition as newer communities replace older ones.
A) rejuvenation
B) mass extinction
C) ecological succession
D) patch dynamics
62) If a lava flow completely denudes a mountain, leaving only bare rock, what type of
succession will follow?
A) primary
B) secondary
C) tertiary
D) quaternary
63) The first species to colonize previously disturbed or damaged ecosystems are called a(n)
A) sere.
B) pioneer community.
C) successor.
D) establishment.
64) If a forest fire destroyed the vegetation in an area, but left some vestiges of the previously
functioning community and the soil intact, what type of succession would follow?
A) primary
B) secondary
C) tertiary
D) quaternary
65) Which of the following is the correct order of lake succession, from lowest to highest
nutrient levels?
A) oligotrophic, mesotrophic, eutrophic
B) eutrophic, oligotrophic, mesotrophic
C) mesotrophic, eutrophic, oligotrophic
D) oligotrophic, eutrophic, mesotrophic
66) In which portion of a lake would oligotrophic conditions most likely occur?
A) along the shore
B) in shallow bays
C) in deep water
D) in areas where high nutrient inputs occur.
67) Human caused eutrophication is known as
A) oligotrophication.
B) mesotrophication.
C) cultural eutrophication.
D) anthropotrophication.
68) Which of the following is not a measure of biological diversity?
A) species diversity
B) genetic diversity
C) ecosystem diversity
D) species diversity, genetic diversity, and ecosystem diversity are all measures of biodiversity.
69) The origin of the Earth’s biological diversity is embodied in
A) the life zone concept.
B) the theory of evolution.
C) ecological succession principle.
D) competitive exclusion principle.
70) The notion that the traits that help a species survive and reproduce are passed along more
frequently than those that do not (i.e. differential reproduction and adaptation) is known as
A) Lamarckianism.
B) punctuated equilibrium.
C) natural selection.
D) gradualism.
71) When a random occurrence produces altered genetic material and inserts new traits into the
inherited stream, ________ has occurred.
A) Lamarckian evolution
B) punctuated equilibrium
C) mutation
D) vicariance
72) Continental drift separating a once continuous population is an example of
A) Lamarckian evolution
B) punctuated equilibrium
C) mutation
D) vicariance
73) Studies have shown that ________ biodiversity in an ecosystem leads to ________ long-term
stability and productivity.
A) greater; greater
B) greater; less
C) less; greater
D) less; slightly more
74) The ability of an ecosystem to recover quickly from a disturbance and return to its original
state is known as
A) resilience.
B) vicariance.
C) punctuated equilibrium.
D) succession.
75) A monocultural agriculture community is ________ vulnerable to disturbance than an area
with high biodiversity.
A) less
B) more
C) equally
76) Since life arose on Earth, ________ major extinctions have occurred.
A) one
B) two
C) six
D) ten
77) Approximately what percentage of plant and animal species have been classified overall.
A) 1%
B) 13%
C) 67%
D) 92%
78) Which of the following has the highest number of known species?
A) plants
B) insects
C) chordates
D) bacteria
79) Which of the following is not considered among the greatest anthopogenic threats to
biodiversity?
A) habitat loss
B) introduction of non-native species
C) air, water, and soil pollution
D) climate change
E) habitat loss, non-native species, pollution, and climate change all represent threats to
biodiversity
80) Increased foliage cover in parts of Australia has been attributed to which of the following
climate change related phenomena.?
A) sea level rise
B) cloud albedo forcing
C) CO2 fertilization effect
D) cloud greenhouse forcing
19.2 True/False Questions
1) An ecosystem is a self-regulating association of living plants and animals and their nonliving
physical environment.
2) The term ecology literally means “the study of the household.”
3) Biogeography is the study of the spatial distribution of plants, whereas zoogeography is the
study of the spatial distribution of animals.
4) Of the total energy intercepted at the Earth’s surface and available for work, about 25% is
fixed by photosynthesis as carbohydrates in plants.
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5) Respiration is essentially the reverse of the photosynthetic process.
6) Net primary productivity is a measurement of how much each individual plant
photosynthesizes.
7) On average, algal beds and reefs have higher net primary productivity than tropical rain
forests.
8) Hydrogen, oxygen, and carbon together make up more than 99% of the Earth’s biomass.
9) Atmospheric nitrogen is readily available to living organisms.
10) As energy moves through trophic levels is increases from lower to higher levels.
11) Approximately half of the cultivated acreage in the United States and Canada is planted for
animal consumption.
12) Some harmful chemicals that are long-lived, stable, and soluble in fatty tissues become
increasingly concentrated at each higher trophic level.
13) A leech that sucks blood from an animal is in an example of commensalism.
14) Plants remove a relatively insignificant amount of carbon dioxide from the atmosphere.
15) Communities are not static, rather they undergo changes over time due to various natural
disturbances.
16) An ecological niche is essentially the same thing as a habitat.
17) According to the competitive exclusion principle, no two species can occupy the same niche.
18) Lichen, which is a composite organism consisting of an alga and fungus, is an example of
mutualism.
19) The distribution of species is based on both biotic and abiotic factors.
20) Altitudinal community assemblages at a constant latitude are often similar to latitudinal
community assemblages at a constant elevation.
21) Plants colonizing bare rock after a volcanic eruption denudes the area is an example of
primary succession.
22) Primary succession is more common than secondary succession.
23) Contemporary biogeographic and ecological thinking posits that disturbance constantly
disrupts ecosystems and a community may never reach the stage of climax community.
24) Different patches across a landscape may be at different successional stages.
25) A lake classified as oligotrophic has high nutrient content.
26) Within a lake, eutrophic conditions predominate in deep, open water.
27) The term biodiversity encompasses not only the number and variety of different species, but
also genetic variations within a species and even the varieties of ecosystems, habitats, and
communities in an area.
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28) An orogeny that separates a once continuous population of a species is an example of
vicariance.
29) Greater biological diversity in an ecosystem leads to greater long-term stability and
productivity.
30) A stable ecosystem is one that is not undergoing any change.
31) A resilient species or ecosystem is one that can recover quickly from disturbance.
32) Species extinctions have occurred throughout Earth’s history, so the recent loss of species is
likely something of little concern.
33) Most of the Earth’s organisms have been identified and classified.
34) Bacteria are the largest (i.e. number of species) group of organisms.
35) Habitat loss, pollution, resource exploitation, climate change, and introduction of non-native
species are among the biggest threats to biodiversity.
36) Addressing and mitigating climate change may become an essential component of species
conservation.
37) There is little evidence supporting the contention that synthetic fertilizers disrupt natural
biogeochemical cycles.
38) Increased atmospheric CO2 may lead to increased foliage cover.
19.3 Essay Questions
1) What is an ecosystem? What is the spatial scale of an ecosystem? Provide some examples of
an ecosystem.
2) What is biogeography? What subjects do biogeographers study? What is ecology? How does
biogeography vary from ecology?
3) Describe the main abiotic ecosystem components. Give at least two regional examples of how
these elements combine to form ecosystems.
4) Using Figure 19.4 and Table 19.1 as your guide, describe the net primary productivity of the
area in which you live. How does this net primary productivity vary across your state (or
equivalent) and broader region?
5) Consider the ecology of the region in which you live. Which organisms are the primary
producers, the primary consumers, the secondary consumers, and tertiary consumers.
6) Using outside sources, provide an example of each of the following symbiotic relationships:
mutualism, parasitism, commensalism, and amensalism.
7) Using outside forces, describe the limiting factor of an organism and how it affects this
organisms distribution.
8) Provide a hypothetical or a historical example of both primary and secondary succession.
9) What is biodiversity? How does biodiversity arise. Why is biodiversity important.
10) What are the major threats to biodiversity in the coming decades? Explain your selections.