Chapter 21

Question 1

Select from the following list the individual who wrote: “The equatorial zone, in short, exhibits
to us the result of a comparatively continuous and unchecked development of organic forms;
while in the temperate regions there have been a series of periodical checks and extinctions of
a more or less disastrous nature, necessitating the commencement of the work of development
in certain lines over and over again. In the one, evolution has had a fair chance; in the other, it
has had countless difficulties thrown in its way.”
A) Henry Chandler Cowles C) Alfred Russel Wallace
B) Frederic Edward Clements D) Henry Allen Gleason
E) Charles Darwin

Answer 1

C) Alfred Russel Wallace

Question 2

The tropical regions of the earth have occupied approximately the same area of land since the
beginning of the Paleozoic era.
A) True B) False

Answer 2

B) False

Question 3

During periods of glacial expansion during the Pleistocene epoch, tropical regions experienced:
A) increased rainfall and higher temperatures.
B) increased rainfall and lower temperatures.
C) decreased rainfall and higher temperatures.
D) decreased rainfall and lower temperatures.

Answer 3

D) decreased rainfall and lower temperatures.

Question 4

Contraction and fragmentation of tropical rain forest habitat during periods of glacial expansion
could have had which of the following effects on biological diversity?
A) extinction of existing species C) Both A and B are possible.
B) formation of new species

Answer 4

C) Both A and B are possible.

Question 5

The ocean basins, because they are interconnected by continuous corridors of water, lack any
differentiation of their floras and faunas.
A) True B) False

Answer 5

B) False

Question 6

The oxygen in our present‐day atmosphere was largely produced by:
A) evaporation of oxygen‐rich comets entering earth’s upper atmosphere.
B) volcanic eruptions.
C) photosynthetic microbes active during the early part of earth’s history.
D) the proliferation of flowering plants during the Cretaceous period.

Answer 6

C) photosynthetic microbes active during the early part of earth’s history.

Question 7

Which of the following is the basic building block of all modern complex organisms?
A) the prokaryotic cell C) the archaebacteria
B) the eukaryotic cell D) the eubacteria

Answer 7

B) the eukaryotic cell

Question 8

Approximately 540 million years ago, most modern phyla of invertebrates appeared rather
suddenly in the fossil record. This first appearance of life in modern form establishes the
beginning of __________.
A) the Cenozoic era B) the Mesozoic era C) the Paleozoic era D) the Modern era

Answer 8

C) the Paleozoic era

Question 9

Which of the following eras refers to “middle animals” and is also known as the age of reptiles?
A) the Cenozoic era B) the Mesozoic era C) the Paleozoic era D) the Modern era

Answer 9

B) the Mesozoic era

Question 10

Which of the following eras refers to “recent animals” and is also known as the age of
mammals?
A) the Cenozoic era B) the Mesozoic era C) the Paleozoic era D) the Modern era

Answer 10

A) the Cenozoic era

Question 11

Students of ecology and evolution are interested in continental drift because:
A) continental drift creates and breaks down barriers to dispersal.
B) the positions of the drifting continents affect global climatic patterns.
C) both of the above.

Answer 11

C) both of the above.

Question 12

Alfred Russel Wallace recognized six major biogeographic regions based on the distributions of
animals he observed. Today we understand that these regions are distinctive:
A) because each biogeographic region has unique climates not found in any of the other
regions.
B) because the plants and animals in each region do not occur in any of the other regions.
C) because they correspond to landmasses isolated millions of years ago by continental drift.
D) as reflections of the political map of Wallace’s time, but have little biological meaning.

Answer 12

C) because they correspond to landmasses isolated millions of years ago by continental drift.

Question 13

Which of the following pairs of biogeographic regions has the greatest affinity of flora and
fauna, the result of a long history of land connection?
A) temperate North America (Nearctic) and tropical South America (Neotropical)
B) temperate Asia (Palearctic) and tropical Asia (Indomalayan)
C) tropical Africa (Afrotropical) and Australia/New Guinea (Australasian)

Answer 13

B) temperate Asia (Palearctic) and tropical Asia (Indomalayan

Question 14

Which of the following pairs of biogeographic regions has the most recent land connection?
A) temperate North America (Nearctic) and tropical South America (Neotropical)
B) temperate Asia (Palearctic) and tropical Asia (Indomalayan)
C) tropical Africa (Afrotropical) and Australia/New Guinea (Australasian)

Answer 14

A) temperate North America (Nearctic) and tropical South America (Neotropical)

Question 15

The temperate forests of Asia (Palearctic region) contain a high percentage of tree species
derived primarily from tropical forests of which of the following biogeographic regions?
A) Neotropical B) Afrotropical C) Indomalayan D) Australasian

Answer 15

C) Indomalayan

Question 16

Under which of the following conditions is a polar region likely to have the warmest climate?
A) when it is occupied by a continent
B) when it is occupied by a landlocked sea
C) when it is occupied by an ocean that extends to tropical areas

Answer 16

C) when it is occupied by an ocean that extends to tropical areas

Question 17

Many forest trees of eastern North America migrated northward from southern refuges
following the retreat of glaciers after the last glacial maximum (about 18,000 years ago). We
know much about these migrations because:
A) we have historical records maintained by Native American peoples.
B) all of these species retain populations in areas that served as refuges.
C) pollen grains deposited in lakes and bogs provide a record of past distributions of these
species.
D) all of the above

Answer 17

C) pollen grains deposited in lakes and bogs provide a record of past distributions of these
species.

Question 18

Native American peoples living in eastern North America and south of the glacial limit around
18,000 years ago would have been part of:
A) an arctic tundra biome dominated by low shrubs and grasses.
B) a boreal forest biome dominated by spruce.
C) a deciduous forest biome dominated by temperate species such as elm and oak.
D) a tropical rainforest biome dominated by diverse broadleaved evergreen trees.
E) a subtropical desert biome dominated by cacti and microphyllous shrubs.

Answer 18

B) a boreal forest biome dominated by spruce.

Question 19

As glaciers retreated northward in Europe following the last glacial advance, various tree
species also expanded their ranges northward into areas of suitable climate. However, Svenning
and Skog have shown that not all species have fully exploited suitable habitat. Of the two
groups of species below, which has less fully exploited suitable habitat?
A) light‐seeded species like silver birch and common hornbeam
B) heavy‐seeded species like sweet chestnut and Pyrenean oak

Answer 19

B) heavy‐seeded species like sweet chestnut and Pyrenean oak

Question 20

Plants and animals of North and South American deserts resemble each other morphologically.
What process is responsible for this similarity?
A) descent from common ancestors
B) convergence
C) repeated migrations of plants and animals from one region to the other
D) all of the above

Answer 20

B) convergence

Question 21

When University of Minnesota ecologist Jeannine Cavender‐Bares and colleagues examined the
distributions of oak species along an environmental moisture gradient in Florida, what did they
find when they examined species belonging to the same evolutionary lineage (e.g., red oaks)?
A) These species tended to be present in the same habitat.
B) These species tended not to be present in the same habitat.

Answer 21

B) These species tended not to be present in the same habitat

Question 22

When University of Minnesota ecologist Jeannine Cavender‐Bares and colleagues examined the
distributions of oak species along an environmental moisture gradient in Florida, under what
circumstance did they find the greater amount of overlap in species distributions?
Chapter 21: History, Biogeography, and Biodiversity
Page 259
A) when these species belonged to the same evolutionary lineage
B) when these species belonged to different evolutionary lineages

Answer 22

A) when these species belonged to the same evolutionary lineage

Question 23

In experimental soil communities consisting of eight mycorrhizal fungi, Maherali and
Klironomos found that communities that retained the greatest number of species over time
were those comprised of fungi from __________ fungal families.
A) one B) two C) three D) any number of

Answer 23

C) three

Question 24

Comparisons among temperate forests on different continents, among other examples, have
led ecologists to which of the following conclusions?
A) Communities in similar environments often have the same numbers of species.
B) Communities in similar environments often have different numbers of species.

Answer 24

B) Communities in similar environments often have different numbers of species

Question 25

Considering the history of earth’s biota, it is clear that regional species pools have varied
considerably in size through time. Given some degree of dependence of local species diversity
on the regional species pool, this finding would lead one to conclude that:
A) ecological systems easily attain equilibrium.
B) ecological systems rarely, if ever, attain equilibrium.

Answer 25

B) ecological systems rarely, if ever, attain equilibrium.

Question 26

Considering the past history of the flora of European temperate deciduous forests, what would
you predict about the temperature tolerance of species present in the Pliocene fossil record
that are now extinct in the region?
A) These species are typically cold‐tolerant.
B) These species are typically cold‐intolerant.

Answer 26

B) These species are typically cold‐intolerant.

Question 27

The greater diversity of mangrove forests in the Indo‐West Pacific region compared to similar
forests in the Atlantic‐Caribbean region may be attributable to:
A) plant taxa invading mangrove habitats more frequently, possibly due to greater isolation of
mangrove habitats.
B) a much larger area of suitable mangrove habitat in the Indo‐West Pacific region.

Answer 27

A) plant taxa invading mangrove habitats more frequently, possibly due to greater isolation of
mangrove habitats.

Question 28

Although diversity of communities is affected by processes acting on the local level, it is also
directly related to regional rates of species production and immigration.
A) True B) False

Answer 28

A) True

Question 29

Which of the following takes place on the longest temporal scale?
A) formation of new species after prolonged isolation of subpopulations
B) selective replacement of genotypes within populations (evolution)
C) interactions between populations (competitive exclusion)
D) death and replacement of individuals in populations (demography and population
regulation)
E) individual movements (behavior)

Answer 29

A) formation of new species after prolonged isolation of subpopulations

Question 30

Because history and geography affect the diversification of species, it may be difficult to
interpret patterns of diversity solely in terms of local environmental conditions.
A) True B) False

Answer 30

A) True

Question 31

The diversity of marsupial mammals in Australia is not a reflection of some special
environmental condition that favors such animals, but rather the legacy of past history, a socalled
__________.

Answer 31

phylogenetic effect

Question 32

The splitting of a widely distributed ancestral population by continental drift (as seen in the
large flightless birds of the ratite lineage), or some other barrier to dispersal, is called
__________.

Answer 32

vicariance

Question 33

Movement of landmasses on the surface of the earth is called __________.

Answer 33

continental drift

Question 34

The breakup of Pangaea near the beginning of the Cretaceous period resulted in two
megacontinents; the more northern of these has been named __________.

Answer 34

Laurasia

Question 35

Wallace’s __________ biogeographic region corresponds closely to the North American
continent.

Answer 35

Nearctic

Question 36

The __________ biogeographic region is the only one of Wallace’s six biogeographic regions
that presently lacks a direct land connection to at least one of the other regions.

Answer 36

Australasian

Question 37

Although adrift until its collision 45 Mya with Asia, the Indian subcontinent is now part of the
__________ biogeographic region.

Answer 37

Indomalayan

Question 38

Svenning and Skog used __________ to determine areas of suitable habitat for comparison
with current distributions of European tree species.

Answer 38

ecological niche modeling

Question 39

When a large proportion of species and higher taxa have been eliminated from earth by a
catastrophic event, the episode is referred to as a(n) __________.

Answer 39

mass extinction

Question 40

During periods of glacial advance and climatic deterioration, it is thought that warm‐temperate
flora and fauna of eastern North America migrated southward to areas bordering __________.

Answer 40

the Gulf of Mexico (or to Florida or the Bahamas, etc.)

Question 41

Pairs of unrelated African and South American rain forest mammals with similar lifestyles and
adaptations are an example of __________.

Answer 41

convergence

Question 42

Dolphins and penguins, although similar in form to fast‐swimming fish such as tuna, are actually
descended from __________ ancestors.

Answer 42

terrestrial

Question 43

Evolution tends to be conservative; that is, small evolutionary changes are more likely than
more substantial __________ that allow organisms to occupy different types of habitat.

Answer 43

adaptive shifts

Question 44

To determine the course of species richness over long periods of time, researchers like
Smithsonian scientist Carlos Jaramillo have turned to analysis of the __________.

Answer 44

fossil record

Question 45

Although ecology has traditionally focused on local and contemporary systems, it is now
expanding its scope to consider the parallel and larger‐scale effects of __________ and
historical processes, respectively.

Answer 45

biogeographic