A virgin pine forest covers a valley, and one of the inhabitants is a red squirrel species. A large volcanic eruption occurs and separates the valley with a huge lava flow, thus producing two populations of squirrels. What must occur for the two populations of squirrels to be considered separate species?
A. The two squirrel populations must feed on different species of plants.
B. The environment must change so that the populations exist in distinct habitats.
C. The fur color or other morphological characteristic of the two squirrel populations must become distinct.
D. The two squirrel populations must select mates using different behaviors.
E. The two squirrel populations must be reproductively isolated.
Clarify Question
· What is the key concept addressed by the question?
· What type of thinking is required?
Gather Content
· What do you already know about speciation?
Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
Reflect on Process · Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
E. The two squirrel populations must be reproductively isolated.
Clarify Question
· What is the key concept addressed by the question?
o This question addresses the biological species concept.
· What type of thinking is required?
o This question is asking you to take what you already know and apply it to this unfamiliar situation.
Gather Content
· What do you already know about speciation?
o The biological species concept says that a species is composed of populations whose members mate with each other and produce fertile offspring. Conversely, populations whose members do not mate with each other or who cannot produce fertile offspring are said to be reproductively isolated and, therefore, are members of different species.
o Thus, populations are considered to be different species when the members are reproductively isolated from each other.
Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
o Do two different species have to eat different foods? Not necessarily.
o Do two different species have to live in different habitats? Not necessarily.
o Do two different species have to look different? Not necessarily.
o Do two different species have to have different mating behavior? Not necessarily.
o Do two different species have to be reproductively isolated? Yes! According to the biological species concept, that is the essential feature that defines two populations as different species.
Reflect on Process · Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
o The question required you to take what you already know and apply it to this unfamiliar situation.
o Did you recognize that the essential criterion that defines different species is that they are reproductively isolated?
You might also like to view...
A student observes a wormlike organism crawling about on dead organic matter. Later, the organism sheds its outer covering. One possibility is that the organism is a larval insect (like a maggot)
However, it might be a member of the phylum ________, and one way to distinguish between the two possibilities is by looking for the presence or absence of ________. A) Platyhelminthes; a cuticle of chitin B) Nematoda; an alimentary canal C) Annelida; a body cavity D) Nematoda; a circulatory system E) Annelida; muscle in the body wall
In a particular E. coli strain, a mutation in the thiMD operon results in improper formation of the stem loop secondary structure making it impossible to bind TPP. There are two enzymes encoded by the thiMD operon
How many of the enzymes encoded in the thiMD operon are translated? A. two B. zero C. three D. one
Which of the following is TRUE of a genetic mutation?
A. It always produces harmful effects. B. It never affects protein structure or function. C. It is not a mechanism through which biological evolution occurs. D. It happens quite frequently in a population. E. It generally produces a change in the DNA sequence of a gene.
The process illustrated in Figure 13-3 is:
a. DNA synthesis. b. translation. c. transcription. d. a frame shift mutation. e. protein synthesis