North American gray wolves usually have mixed gray and white fur, but some members of the species have a version...
GMAT Information and Ideas : (Ideas) Questions
North American gray wolves usually have mixed gray and white fur, but some members of the species have a version of a gene, or gene variant, that gives them a mostly black coat instead. Sarah Cubaynes and her team studied twelve populations of North American gray wolves. They found that the black-furred wolves are more common in areas where outbreaks of distemper virus happen regularly. The team also discovered that the black-furred wolves are more likely to be immune to distemper than the gray-furred wolves are. Taken together, these findings suggest that ______
Which choice most logically completes the text?
Step 1: Decode and Map the Passage
Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "North American gray wolves usually have mixed gray and white fur, but some members of the species have a version of a gene, or gene variant, that gives them a mostly black coat instead." |
|
| "Sarah Cubaynes and her team studied twelve populations of North American gray wolves." |
|
| "They found that the black-furred wolves are more common in areas where outbreaks of distemper virus happen regularly." |
|
| "The team also discovered that the black-furred wolves are more likely to be immune to distemper than the gray-furred wolves are." |
|
Provide Passage Architecture & Core Elements
Main Point: Research reveals that black-furred wolves are both more common in distemper-prone areas and more immune to distemper, suggesting a connection between the gene variant and disease immunity.
Argument Flow: The passage establishes that some wolves have a gene variant causing black fur, then presents two related research findings: black wolves cluster in distemper-outbreak areas and show greater immunity to distemper. These findings together point toward a logical connection between the genetic trait and disease resistance.
Step 2: Interpret the Question Precisely
This is a fill-in-the-blank question asking us to choose the best logical connector. The answer must create the right relationship between what comes before and after the blank.
Step 3: Prethink the Answer
- We have two key findings that need to connect logically:
- Black wolves are more common where distemper outbreaks happen regularly
- Black wolves are more immune to distemper than gray wolves
- The logical bridge here is that the gene variant causing black fur might also provide disease immunity
- This would explain both patterns: black wolves survive better in distemper areas (so they're more common there) because they have better immunity
- Claims North American gray wolves have more distemper outbreaks than other wolf species
- This makes a comparison the passage never provides
- Doesn't connect the two key findings about black fur and immunity
- States that the gene variant for black fur may be linked to distemper immunity
- Perfectly connects both research findings: if the gene variant provides immunity, black wolves would thrive in distemper areas and show better immunity
- Discusses average lifespan of gray wolves increasing over time
- Focuses on gray wolves specifically when the key findings are about black wolves
- Doesn't explain the connection between location patterns and immunity findings
- Predicts gray-furred wolves will replace black-furred wolves
- Contradicts the research findings, which suggest black wolves have advantages in distemper areas