Modern dog breeds are largely the result of 160 years of owners crossbreeding certain dogs in order to select for...
GMAT Information and Ideas : (Ideas) Questions
Modern dog breeds are largely the result of 160 years of owners crossbreeding certain dogs in order to select for particular physical appearances. Owners often say that some breeds are also more likely than others to have particular personality traits—basset hounds are affectionate; boxers are easy to train—but Kathleen Morrill and colleagues found through a combination of owner surveys and DNA sequencing of 2,000 dogs that while physical traits are predictably heritable among purebred dogs, behavior varies widely among dogs of the same breed.
Which choice best states the main idea of the text?
Dog breeds would not exist without many years of human intervention in dogs' reproduction.
Research fails to confirm a commonly held belief about dog breeds and behavior.
The dog breeds most popular among owners have often changed over the past 160 years.
A study of dog breeds is notable for its usage of both opinion surveys and DNA sequencing.
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "Modern dog breeds are largely the result of 160 years of owners crossbreeding certain dogs in order to select for particular physical appearances." |
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| "Owners often say that some breeds are also more likely than others to have particular personality traits—basset hounds are affectionate; boxers are easy to train—" |
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| "but Kathleen Morrill and colleagues found through a combination of owner surveys and DNA sequencing of 2,000 dogs that while physical traits are predictably heritable among purebred dogs, behavior varies widely among dogs of the same breed." |
|
Part B: Provide Passage Architecture & Core Elements
Main Point: Research contradicts the common belief that dog breeds have predictable personality traits, showing that while physical characteristics are heritable, behavioral traits vary widely within the same breed.
Step 2: Interpret the Question Precisely
What's being asked? The main idea of the entire text
What type of answer do we need? The central message or primary point that the passage is trying to convey
Any limiting keywords? "Main idea" tells us we need the overarching point, not a supporting detail
Step 3: Prethink the Answer
- The right answer should capture that this passage is fundamentally about research challenging a common assumption
- The key elements should be:
- There's a commonly held belief about dog breeds and behavior
- Research tested this belief
- The research findings contradicted what people commonly believe
Dog breeds would not exist without many years of human intervention in dogs' reproduction.
- This focuses on the background information about how breeds developed through human intervention
- While this detail is mentioned, it's just context—not the main point the passage is making
Research fails to confirm a commonly held belief about dog breeds and behavior.
- This perfectly captures what we identified: research contradicting a common belief
- Matches our prethinking exactly—the Morrill study failed to confirm what owners commonly believe about breed behavior
The dog breeds most popular among owners have often changed over the past 160 years.
- The passage never mentions anything about changing popularity of breeds over time
- This introduces information that simply isn't in the text
A study of dog breeds is notable for its usage of both opinion surveys and DNA sequencing.
- This focuses on the research methodology (surveys + DNA sequencing) rather than the findings
- While the methodology is mentioned, it's a supporting detail, not the main point