Question 1

The largest unit within which gene flow can readily occur is a

Accepted Answer

A)  population. 
B)  species. 
C)  genus. 
D)  hybrid. 
E)  phylum. 
A)  population. 
B)  species. 
C)  genus. 
D)  hybrid. 
E)  phylum.

Question 2

The next few questions refer to the following description.
On the Bahamian island of Andros, mosquitofish populations live in various, now-isolated, freshwater ponds that were once united. Currently, some predator-rich ponds have mosquitofish that can swim in short, fast bursts; other predator-poor ponds have mosquitofish that can swim continuously for a long time. When placed together in the same body of water, the two kinds of female mosquitofish exhibit exclusive breeding preferences.
-What is the best way to promote fusion between two related populations of mosquitofish, one of which lives in a predator-rich pond, and the other of which lives in a predator-poor pond?

Accepted Answer

A)  Build a canal linking the two ponds that permits free movement of mosquitofish, but not of predators. 
B)  Transfer only female mosquitofish from a predator-rich pond to a predator-poor pond. 
C)  Perform a reciprocal transfer of females between predator-rich and predator-poor ponds. 
D)  Remove predators from a predator-rich pond and transfer them to a predator-poor pond. 
A)  Build a canal linking the two ponds that permits free movement of mosquitofish, but not of predators. 
B)  Transfer only female mosquitofish from a predator-rich pond to a predator-poor pond. 
C)  Perform a reciprocal transfer of females between predator-rich and predator-poor ponds. 
D)  Remove predators from a predator-rich pond and transfer them to a predator-poor pond.

Question 3

Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species. Recently, these birds have been reclassified as eastern and western forms of a single species, the yellow-rumped warbler. Which of the following pieces of evidence, if true, would be cause for this reclassification?

Accepted Answer

A)  The two forms interbreed often in nature, and their offspring survive and reproduce well. 
B)  The two forms live in similar habitats. 
C)  The two forms have many genes in common. 
D)  The two forms have similar food requirements. 
E)  The two forms are very similar in coloration. 
A)  The two forms interbreed often in nature, and their offspring survive and reproduce well. 
B)  The two forms live in similar habitats. 
C)  The two forms have many genes in common. 
D)  The two forms have similar food requirements. 
E)  The two forms are very similar in coloration.

Question 4

The next few questions refer to the following description.
In the ocean, on either side of the Isthmus of Panama, are 30 species of snapping shrimp; some are shallow-water species, and others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago.
In Figure 22.1, the isthmus separates the Pacific Ocean on the left (side A) from the Atlantic Ocean on the right (side B). The seawater on either side of the isthmus is separated into five depth habitats (1-5), with 1 being the shallowest.
   Figure 22.1
-Which of these habitats is likely to harbor the youngest species?

Accepted Answer

A)  A5 
B)  B4 
C)  A3 
D)  B2 
E)  A1 
A)  A5 
B)  B4 
C)  A3 
D)  B2 
E)  A1

Question 5

The next question refers to the following description.
In the ocean, on either side of the Isthmus of Panama, are 30 species of snapping shrimp; some are shallow-water species, others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago. The oceans were completely separated by the isthmus about 3 million years ago.
-Why should deepwater shrimp on different sides of the isthmus have diverged from each other earlier than shallow-water shrimp?

Accepted Answer

A)  They have been geographically isolated from each other for a longer time. 
B)  Cold temperatures, associated with deep water, have accelerated the mutation rate, resulting in faster divergence in deepwater shrimp. 
C)  The rise of the land bridge was accompanied by much volcanic activity. Volcanic ash contains heavy metals, which are known mutagens. Ash fall caused high levels of heavy metals in the ocean sediments underlying the deep water, resulting in accelerated mutation rates and faster divergence in deepwater shrimp. 
D)  Fresh water entering the ocean from the canal is both less dense and cloudier than seawater. The cloudy fresh water interferes with the ability of shallow-water shrimp to locate mating partners, which reduces the frequency of mating, thereby slowing the introduction of genetic variation. 
A)  They have been geographically isolated from each other for a longer time. 
B)  Cold temperatures, associated with deep water, have accelerated the mutation rate, resulting in faster divergence in deepwater shrimp. 
C)  The rise of the land bridge was accompanied by much volcanic activity. Volcanic ash contains heavy metals, which are known mutagens. Ash fall caused high levels of heavy metals in the ocean sediments underlying the deep water, resulting in accelerated mutation rates and faster divergence in deepwater shrimp. 
D)  Fresh water entering the ocean from the canal is both less dense and cloudier than seawater. The cloudy fresh water interferes with the ability of shallow-water shrimp to locate mating partners, which reduces the frequency of mating, thereby slowing the introduction of genetic variation.

Question 6

What does the biological species concept use as the primary criterion for determining species boundaries?

Accepted Answer

A)  geographic isolation 
B)  niche differences 
C)  gene flow 
D)  morphological similarity 
E)  molecular (DNA, RNA, protein) similarity 
A)  geographic isolation 
B)  niche differences 
C)  gene flow 
D)  morphological similarity 
E)  molecular (DNA, RNA, protein) similarity

Question 7

Which habitats should harbor snapping shrimp species with the greatest degree of genetic divergence from each other?

Accepted Answer

A)  A1 and A5 
B)  A1 and B5 
C)  B5 and B1 
D)  A5 and B5 
E)  Both A1/A5 and B1/B5 should have the greatest, but equal amounts of, genetic divergence. 
A)  A1 and A5 
B)  A1 and B5 
C)  B5 and B1 
D)  A5 and B5 
E)  Both A1/A5 and B1/B5 should have the greatest, but equal amounts of, genetic divergence.

Question 8

The most likely explanation for the recent decline in cichlid species diversity in Lake Victoria is

Accepted Answer

A)  reinforcement. 
B)  fusion. 
C)  stability. 
D)  geographic isolation. 
E)  polyploidy. 
A)  reinforcement. 
B)  fusion. 
C)  stability. 
D)  geographic isolation. 
E)  polyploidy.

Question 9

The next few questions refer to the following description.
On the Bahamian island of Andros, mosquitofish populations live in various, now-isolated, freshwater ponds that were once united. Currently, some predator-rich ponds have mosquitofish that can swim in short, fast bursts; other predator-poor ponds have mosquitofish that can swim continuously for a long time. When placed together in the same body of water, the two kinds of female mosquitofish exhibit exclusive breeding preferences.
-If one builds a canal linking a predator-rich pond to a predator-poor pond, then what type(s) of selection should subsequently be most expected among the mosquitofish in the original predator-rich pond, and what type(s) should be most expected among the mosquitofish in the formerly predator-poor pond?

Accepted Answer

A)  stabilizing selection; directional selection 
B)  stabilizing selection; stabilizing selection 
C)  less-intense directional selection; more-intense directional selection 
D)  less-intense disruptive selection; more-intense disruptive selection 
A)  stabilizing selection; directional selection 
B)  stabilizing selection; stabilizing selection 
C)  less-intense directional selection; more-intense directional selection 
D)  less-intense disruptive selection; more-intense disruptive selection

Question 10

The next few questions refer to the following description.
On the volcanic, equatorial West African island of Sao Tomé, two species of fruit fly exist. Drosophila yakuba inhabits the island's lowlands, and is also found on the African mainland, located about 200 miles away. At higher elevations, and only on Sao Tomé, is found the very closely related Drosophila santomea. The two species can hybridize, though male hybrids are sterile. A hybrid zone exists at middle elevations, though hybrids there are greatly outnumbered by D. santomea. Studies of the two species' nuclear genomes reveal that D. yakuba on the island is more closely related to mainland D. yakuba than to D. santomea (2n = 4 in both species). Sao Tomé rose from the Atlantic Ocean about 14 million years ago.
-Which of the following reduces gene flow between the gene pools of the two species on Sao Tomé, despite the existence of hybrids?

Accepted Answer

A)  hybrid breakdown 
B)  hybrid inviability 
C)  hybrid sterility 
D)  temporal isolation 
E)  a geographic barrier 
A)  hybrid breakdown 
B)  hybrid inviability 
C)  hybrid sterility 
D)  temporal isolation 
E)  a geographic barrier

Question 11

The next few questions refer to the following description.
In the ocean, on either side of the Isthmus of Panama, are 30 species of snapping shrimp; some are shallow-water species, and others are adapted to deep water. There are 15 species on the Pacific side and 15 different species on the Atlantic side. The Isthmus of Panama started rising about 10 million years ago.
In Figure 22.1, the isthmus separates the Pacific Ocean on the left (side A) from the Atlantic Ocean on the right (side B). The seawater on either side of the isthmus is separated into five depth habitats (1-5), with 1 being the shallowest.
   Figure 22.1
-In which habitat should one find snapping shrimp most closely related to shrimp that live in habitat A4?

Accepted Answer

A)  A3 
B)  A5 
C)  B4 
D)  either A3 or A5 
E)  any species from any one of the side A habitats 
A)  A3 
B)  A5 
C)  B4 
D)  either A3 or A5 
E)  any species from any one of the side A habitats

Question 12

There are currently two large, permanent bridges that span the Panama Canal. The bridges are about 8 miles apart. If snapping shrimp avoid swimming at night and avoid swimming under shadows, then what do these bridges represent for the snapping shrimp?

Accepted Answer

A)  sources of refuge 
B)  geographic barriers 
C)  sources of a hybrid zone between the two bridges 
D)  sources for increased gene flow 
A)  sources of refuge 
B)  geographic barriers 
C)  sources of a hybrid zone between the two bridges 
D)  sources for increased gene flow

Question 13

Dogs (Canis lupus familiaris) and gray wolves (Canis lupus) can interbreed to produce viable, fertile offspring. These species shared a common ancestor recently (in geologic time) and have a high degree of genetic similarity, although their anatomies vary widely. Judging from this evidence, which two species concepts are most likely to place dogs and wolves together into a single species?

Accepted Answer

A)  ecological and morphological 
B)  ecological and phylogenetic 
C)  morphological and phylogenetic 
D)  biological and morphological 
E)  biological and phylogenetic 
A)  ecological and morphological 
B)  ecological and phylogenetic 
C)  morphological and phylogenetic 
D)  biological and morphological 
E)  biological and phylogenetic

Question 14

Beetle pollinators of a particular plant are attracted to its flowers' bright orange color. The beetles not only pollinate the flowers, but they mate while inside of the flowers. A mutant version of the plant with red flowers becomes more common with the passage of time. A particular variant of the beetle prefers the red flowers to the orange flowers. Over time, these two beetle variants diverge from each other to such an extent that interbreeding is no longer possible. What kind of speciation has occurred in this example, and what has driven it?

Accepted Answer

A)  allopatric speciation; ecological isolation 
B)  sympatric speciation; habitat differentiation 
C)  allopatric speciation; behavioral isolation 
D)  sympatric speciation; sexual selection 
E)  sympatric speciation; allopolyploidy 
A)  allopatric speciation; ecological isolation 
B)  sympatric speciation; habitat differentiation 
C)  allopatric speciation; behavioral isolation 
D)  sympatric speciation; sexual selection 
E)  sympatric speciation; allopolyploidy

Question 15

Rocky Mountain juniper (Juniperus scopulorum) and one-seeded juniper (J. monosperma) have overlapping ranges. If pollen grains (which contain sperm cells) from one species are unable to germinate and make pollen tubes on female ovules (which contain egg cells) of the other species, then which of these terms is applicable?

Accepted Answer

A)  behavioral isolation 
B)  mechanical isolation 
C)  hybrid breakdown 
D)  reduced hybrid viability 
A)  behavioral isolation 
B)  mechanical isolation 
C)  hybrid breakdown 
D)  reduced hybrid viability

Question 16

The next few questions refer to the following description.
On the Bahamian island of Andros, mosquitofish populations live in various, now-isolated, freshwater ponds that were once united. Currently, some predator-rich ponds have mosquitofish that can swim in short, fast bursts; other predator-poor ponds have mosquitofish that can swim continuously for a long time. When placed together in the same body of water, the two kinds of female mosquitofish exhibit exclusive breeding preferences.
-Which two of the following have operated to increase divergence between mosquitofish populations on Andros? 1. improved gene flow
2) bottleneck effect
3) sexual selection
4) founder effect
5) natural selection

Accepted Answer

A)  1 and 3 
B)  2 and 3 
C)  2 and 4 
D)  3 and 4 
E)  3 and 5 
A)  1 and 3 
B)  2 and 3 
C)  2 and 4 
D)  3 and 4 
E)  3 and 5

Question 17

The next few questions refer to the following description.
On the Bahamian island of Andros, mosquitofish populations live in various, now-isolated, freshwater ponds that were once united. Currently, some predator-rich ponds have mosquitofish that can swim in short, fast bursts; other predator-poor ponds have mosquitofish that can swim continuously for a long time. When placed together in the same body of water, the two kinds of female mosquitofish exhibit exclusive breeding preferences.
-The predatory fish rely on visual cues and speed to capture mosquitofish. Mosquitofish rely on speed and visual cues to avoid the predatory fish. Which adaptation(s) might help the predators survive in ponds that are home to faster mosquitofish? 1. directional selection for increased speed
2) stabilizing selection for speed that matches that of the mosquitofish
3) change in hunting behavior that replaces reliance on visual cues with reliance on tactile cues, which can be used to hunt at night
4) change in hunting behavior that eliminates speed in favor of better camouflage, which permits an ambush strategy

Accepted Answer

A)  1 only 
B)  2 only 
C)  either 1 or 3 
D)  either 2 or 3 
E)  1, 3, or 4 
A)  1 only 
B)  2 only 
C)  either 1 or 3 
D)  either 2 or 3 
E)  1, 3, or 4

Question 18

Rank the following from most general to most specific: 1. gametic isolation
2) reproductive isolating mechanism
3) sperm-egg incompatibility in sea urchins
4) prezygotic isolating mechanism

Accepted Answer

A)  2, 3, 1, 4 
B)  2, 4, 1, 3 
C)  4, 1, 2, 3 
D)  4, 2, 1, 3 
E)  2, 1, 4, 3 
A)  2, 3, 1, 4 
B)  2, 4, 1, 3 
C)  4, 1, 2, 3 
D)  4, 2, 1, 3 
E)  2, 1, 4, 3

Question 19

Using only the information provided in the paragraph, which of the following is the best initial hypothesis for how D. santomea descended from D. yakuba?

Accepted Answer

A)  geographic isolation 
B)  autopolyploidy 
C)  habitat differentiation 
D)  sexual selection 
E)  allopolyploidy 
A)  geographic isolation 
B)  autopolyploidy 
C)  habitat differentiation 
D)  sexual selection 
E)  allopolyploidy

Question 20

Rocky Mountain juniper (Juniperus scopulorum) and one-seeded juniper (J. monosperma) have overlapping ranges. If pollen grains (which contain sperm cells) from one species are unable to germinate and make pollen tubes on female ovules (which contain egg cells) of the other species, then which of these terms are applicable? 1. sympatric species
2) prezygotic isolation
3) postzygotic isolation
4) allopatric species
5) habitat isolation
6) reduced hybrid fertility

Accepted Answer

A)  1 and 2 
B)  2 and 4 
C)  1, 3, and 6 
D)  2, 4, and 5 
E)  1, 2, 5, and 6 
A)  1 and 2 
B)  2 and 4 
C)  1, 3, and 6 
D)  2, 4, and 5 
E)  1, 2, 5, and 6

Exam 22: The Origin of Species

The largest unit within which gene flow can readily occur is a

What does the biological species concept use as the primary criterion for determining species boundaries?

Which habitats should harbor snapping shrimp species with the greatest degree of genetic divergence from each other?

The most likely explanation for the recent decline in cichlid species diversity in Lake Victoria is

There are currently two large, permanent bridges that span the Panama Canal. The bridges are about 8 miles apart. If snapping shrimp avoid swimming at night and avoid swimming under shadows, then what do these bridges represent for the snapping shrimp?

Rank the following from most general to most specific: 1. gametic isolation 2) reproductive isolating mechanism 3) sperm-egg incompatibility in sea urchins 4) prezygotic isolating mechanism

Using only the information provided in the paragraph, which of the following is the best initial hypothesis for how D. santomea descended from D. yakuba?

Introduction: Evolution and the Foundations of Biology

The Chemical Context of Life

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development, Stem Cells, and Cancer

Viruses

Genomes and Their Evolution

Descent With Modification

Phylogeny

The Evolution of Populations

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition, Nutrition, and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Reproduction and Development

Neurons, Synapses, and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Population Ecology and the Distribution of Organisms

Species Interactions

Ecosystems and Energy

Global Ecology and Conservation Biology

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