1. Chapter 16
The Origin of Species

2. Which of the following is a species?
A group of interbreeding individuals that is reproductively isolated from other groups
A group of organisms and their interactions with the environment
The biotic and abiotic components of an ecosystem
An individual organism and its niche
Question: 16-1
Answer: 1
Diff: Easy
Text Ref: Section 16.1
Skill: Factual
Also relates to: Chapter 1
Notes:
This is a good place to discuss the limitations of the definition of species, in that asexual organisms are excluded.

3. Which of the following is a species?
A group of interbreeding individuals that is reproductively isolated from other groups
A group of organisms and their interactions with the environment
The biotic and abiotic components of an ecosystem
An individual organism and its niche
Question: 16-1
Answer: 1
Diff: Easy
Text Ref: Section 16.1
Skill: Factual
Also relates to: Chapter 1
Notes:
This is a good place to discuss the limitations of the definition of species, in that asexual organisms are excluded.

4. Geographical isolation Ecological isolation Temporal isolation
On the basis of differences in DNA and structure, West African elephants are thought to be a different species from Central, East, and South African savanna elephants and Central African forest elephants. Which isolation mechanism has occurred?
Geographical isolation
Ecological isolation
Temporal isolation
Behavioral isolation
Question: 16-2
Answer: 1
Diff: Moderate
Text Ref: Section 16.2
Skill: Application
Notes:
The answer should be obvious in that the different populations are from different geographic areas.

5. Geographical isolation Ecological isolation Temporal isolation
On the basis of differences in DNA and structure, West African elephants are thought to be a different species from Central, East, and South African savanna elephants and Central African forest elephants. Which isolation mechanism has occurred?
Geographical isolation
Ecological isolation
Temporal isolation
Behavioral isolation
Question: 16-2
Answer: 1
Diff: Moderate
Text Ref: Section 16.2
Skill: Application
Notes:
The answer should be obvious in that the different populations are from different geographic areas.

6. Geographical isolation Ecological isolation Temporal isolation
Two populations of the columbine flower had lived at different altitudes in the same area. When the two were reunited, they could no longer breed. Which isolation mechanism has occurred?
Geographical isolation
Ecological isolation
Temporal isolation
Behavioral isolation
Question: 16-3
Answer: 2
Diff: Hard
Text Ref: Section 16.2
Skill: Application
Notes:
This question can be difficult for students in that they may first guess geographical isolation, but the habitats are in the same general area.

7. Geographical isolation Ecological isolation Temporal isolation
Two populations of the columbine flower had lived at different altitudes in the same area. When the two were reunited, they could no longer breed. Which isolation mechanism has occurred?
Geographical isolation
Ecological isolation
Temporal isolation
Behavioral isolation
Question: 16-3
Answer: 2
Diff: Hard
Text Ref: Section 16.2
Skill: Application
Notes:
This question can be difficult for students in that they may first guess geographical isolation, but the habitats are in the same general area.

8. Geographical isolation Ecological isolation Temporal isolation
One firefly population mates right after sundown, and another mates in the middle of the night. Which isolation mechanism is occurring?
Geographical isolation
Ecological isolation
Temporal isolation
Behavioral isolation
Question: 16-4
Answer: 3
Diff: Hard
Text Ref: Section 16.2
Skill: Application
Notes:
This question is difficult for students who do not know what “temporal” means.

9. Geographical isolation Ecological isolation Temporal isolation
One firefly population mates right after sundown, and another mates in the middle of the night. Which isolation mechanism is occurring?
Geographical isolation
Ecological isolation
Temporal isolation
Behavioral isolation
Question: 16-4
Answer: 3
Diff: Hard
Text Ref: Section 16.2
Skill: Application
Notes:
This question is difficult for students who do not know what “temporal” means.

10. Geographical isolation Ecological isolation Temporal isolation
A female cricket does not understand the mating call of a male cricket. Which isolation mechanism is occurring?
Geographical isolation
Ecological isolation
Temporal isolation
Behavioral isolation
Question: 16-5
Answer: 4
Diff: Moderate
Text Ref: Section 16.2
Skill: Application
Notes:
A dance, a change in color, or a mating call can all be involved in behavioral isolation.

11. Geographical isolation Ecological isolation Temporal isolation
A female cricket does not understand the mating call of a male cricket. Which isolation mechanism is occurring?
Geographical isolation
Ecological isolation
Temporal isolation
Behavioral isolation
Question: 16-5
Answer: 4
Diff: Moderate
Text Ref: Section 16.2
Skill: Application
Notes:
A dance, a change in color, or a mating call can all be involved in behavioral isolation.

12. Geographical isolation Ecological isolation Temporal isolation
Sea urchins spawn their gametes freely into the surrounding ocean waters. The sperm of one type of urchin will not fertilize the egg of another type of urchin. Which isolation mechanism is occurring?
Geographical isolation
Ecological isolation
Temporal isolation
Gametic incompatibility
Question: 16-6
Answer: 4
Diff: Easy
Text Ref: Section 16.2
Skill: Application
Notes:
Remind students that they can glean information from the words alone, which provide clues to these different types of isolation mechanisms. The answer should be obvious from the words “gametic incompatibility” that the gametes are unsuitable for one another.

13. Geographical isolation Ecological isolation Temporal isolation
Sea urchins spawn their gametes freely into the surrounding ocean waters. The sperm of one type of urchin will not fertilize the egg of another type of urchin. Which isolation mechanism is occurring?
Geographical isolation
Ecological isolation
Temporal isolation
Gametic incompatibility
Question: 16-6
Answer: 4
Diff: Easy
Text Ref: Section 16.2
Skill: Application
Notes:
Remind students that they can glean information from the words alone, which provide clues to these different types of isolation mechanisms. The answer should be obvious from the words “gametic incompatibility” that the gametes are unsuitable for one another.

14. Geographical isolation Ecological isolation Hybrid inviability
A leopard frog and a wood frog mate and produce offspring, which die within a few days. Which isolation mechanism has occurred?
Geographical isolation
Ecological isolation
Hybrid inviability
Hybrid infertility
Question: 16-7
Answer: 3
Diff: Moderate
Text Ref: Section 16.2
Skill: Application
Notes:
Many students confuse hybrid inviability with hybrid infertility. If students think about what the word “viable” means, they will have an easier time with this one.

15. Geographical isolation Ecological isolation Hybrid inviability
A leopard frog and a wood frog mate and produce offspring, which die within a few days. Which isolation mechanism has occurred?
Geographical isolation
Ecological isolation
Hybrid inviability
Hybrid infertility
Question: 16-7
Answer: 3
Diff: Moderate
Text Ref: Section 16.2
Skill: Application
Notes:
Many students confuse hybrid inviability with hybrid infertility. If students think about what the word “viable” means, they will have an easier time with this one.

16. Geographical isolation Ecological isolation Hybrid inviability
A cross between a male tiger and a female lion is called a tigon. The tigon is sterile. Which isolation mechanism has occurred?
Geographical isolation
Ecological isolation
Hybrid inviability
Hybrid infertility
Question: 16-8
Answer: 4
Diff: Moderate
Text Ref: Section 16.2
Skill: Application
Notes:
Because of the movie Napoleon Dynamite, students may be familiar with ligers—but when the sexes are reversed, a tigon is produced. A liger is produced by a male lion and a female tiger.

17. Geographical isolation Ecological isolation Hybrid inviability
A cross between a male tiger and a female lion is called a tigon. The tigon is sterile. Which isolation mechanism has occurred?
Geographical isolation
Ecological isolation
Hybrid inviability
Hybrid infertility
Question: 16-8
Answer: 4
Diff: Moderate
Text Ref: Section 16.2
Skill: Application
Notes:
Because of the movie Napoleon Dynamite, students may be familiar with ligers—but when the sexes are reversed, a tigon is produced. A liger is produced by a male lion and a female tiger.

18. Two populations of similar-appearing snapping shrimp live on either side of the Isthmus of Panama. When the populations are brought together, neither displays courtship behaviors; they are hostile toward each other. What type of speciation is occurring?
Hybrid infertility
Hybrid inviability
Allopatric
Sympatric
Question: 16-9
Answer: 3
Diff: Easy
Text Ref: Section 16.3
Skill: Application
Notes:
Allopatric speciation has occurred in many marine animals on either side of the Isthmus of Panama, which closed about 3 million years ago.

19. Two populations of similar-appearing snapping shrimp live on either side of the Isthmus of Panama. When the populations are brought together, neither displays courtship behaviors; they are hostile toward each other. What type of speciation is occurring?
Hybrid infertility
Hybrid inviability
Allopatric
Sympatric
Question: 16-9
Answer: 3
Diff: Easy
Text Ref: Section 16.3
Skill: Application
Notes:
Allopatric speciation has occurred in many marine animals on either side of the Isthmus of Panama, which closed about 3 million years ago.

20. More than 300 species of cichlids live in Lake Malawi in Africa
More than 300 species of cichlids live in Lake Malawi in Africa. Although the species are similar, the fish have different diets, gill structures, jaws, and teeth. What type of speciation has occurred?
Hybrid infertility
Hybrid inviability
Allopatric
Sympatric
Question: 16-10
Answer: 4
Diff: Easy
Text Ref: Section 16.3
Skill: Application
Notes:
Sympatric speciation is harder for students to understand than allopatric speciation, because the species are living in the same habitat or ecological area. This is a good time to talk about niche specialization and its influence in sympatric speciation.

21. More than 300 species of cichlids live in Lake Malawi in Africa
More than 300 species of cichlids live in Lake Malawi in Africa. Although the species are similar, the fish have different diets, gill structures, jaws, and teeth. What type of speciation has occurred?
Hybrid infertility
Hybrid inviability
Allopatric
Sympatric
Question: 16-10
Answer: 4
Diff: Easy
Text Ref: Section 16.3
Skill: Application
Notes:
Sympatric speciation is harder for students to understand than allopatric speciation, because the species are living in the same habitat or ecological area. This is a good time to talk about niche specialization and its influence in sympatric speciation.

22. Allopatric speciation Hybrid selection Adaptive radiation Extinction
The cichlids of Lake Malawi displayed __________, quickly taking advantage of unoccupied habitats. (Mammals also did so after the dinosaurs went extinct.)
Allopatric speciation
Hybrid selection
Adaptive radiation
Extinction
Question: 16-11
Answer: 3
Diff: Moderate
Text Ref: Section 16.3
Skill: Application
Also relates to: Chapter 17
Notes:
At this point, students should understand that species can evolve quickly as a result of the different selection pressures organisms experience in different habitats.

23. Allopatric speciation Hybrid selection Adaptive radiation Extinction
The cichlids of Lake Malawi displayed __________, quickly taking advantage of unoccupied habitats. (Mammals also did so after the dinosaurs went extinct.)
Allopatric speciation
Hybrid selection
Adaptive radiation
Extinction
Question: 16-11
Answer: 3
Diff: Moderate
Text Ref: Section 16.3
Skill: Application
Also relates to: Chapter 17
Notes:
At this point, students should understand that species can evolve quickly as a result of the different selection pressures organisms experience in different habitats.

24. What would NOT make pandas vulnerable to extinction?
An extended range as a result of multiple populations throughout China
Overspecialization on bamboo as their food source
Habitat alteration for farms, homes, and businesses
Competition for resources with black bears
Question: 16-12
Answer: 1
Diff: Easy
Text Ref: Section 16.4
Skill: Application
Also relates to: Chapter 17
Notes:
Students tend to think of extinction as a process that is exclusively influenced by humans. They do not realize that it occurs naturally as well. Some factors that influence extinction are a limited range, overspecialization, habitat alteration, and competition. The following fact is in the chapter and is a good one to use in class: “At least 99.9% of all the species that have ever existed are now extinct.”

25. What would NOT make pandas vulnerable to extinction?
An extended range as a result of multiple populations throughout China
Overspecialization on bamboo as their food source
Habitat alteration for farms, homes, and businesses
Competition for resources with black bears
Question: 16-12
Answer: 1
Diff: Easy
Text Ref: Section 16.4
Skill: Application
Also relates to: Chapter 17
Notes:
Students tend to think of extinction as a process that is exclusively influenced by humans. They do not realize that it occurs naturally as well. Some factors that influence extinction are a limited range, overspecialization, habitat alteration, and competition. The following fact is in the chapter and is a good one to use in class: “At least 99.9% of all the species that have ever existed are now extinct.”

26. Mechanical incompatibility Ecological isolation
In the figure, one population eventually becomes two separate species. What is the mechanism producing these two species?
Sympatric isolation
Allopatric isolation
Mechanical incompatibility
Ecological isolation
Question: 16-13
Answer: 2
Diff: Easy
Text Ref: Section 16.3
Skill: Application
Notes:
These lizards originally formed a single reproductive population that occupied the same ecological niche. The rafting experience produced an isolated population that reproduced and evolved in a separate physical location by the process of allopatric isolation. Under these conditions, no gene flow took place between the two separate populations.
Figure 16-9

27. Mechanical incompatibility Ecological isolation
In the figure, one population eventually becomes two separate species. What is the mechanism producing these two species?
Sympatric isolation
Allopatric isolation
Mechanical incompatibility
Ecological isolation
Question: 16-13
Answer: 2
Diff: Easy
Text Ref: Section 16.3
Skill: Application
Notes:
These lizards originally formed a single reproductive population that occupied the same ecological niche. The rafting experience produced an isolated population that reproduced and evolved in a separate physical location by the process of allopatric isolation. Under these conditions, no gene flow took place between the two separate populations.
Figure 16-9