Although most songbirds build open, cupped nests, some species build domed nests with roofs that provide much more protection. Many...
GMAT Information and Ideas : (Ideas) Questions
Although most songbirds build open, cupped nests, some species build domed nests with roofs that provide much more protection. Many ecologists have assumed that domed nests would provide protection from weather conditions and thus would allow species that build them to have larger geographic ranges than species that build open nests do. To evaluate this assumption, a research team led by evolutionary biologist Iliana Medina analyzed data for over 3,000 species of songbirds.
Which finding from Medina and her colleagues' study, if true, would most directly challenge the assumption in the underlined sentence?
Species that build open nests tend to have higher extinction rates than species that build domed nests.
Species that build open nests tend to be smaller in size than species that build domed nests.
Species that build open nests tend to use fewer materials to build their nests than species that build domed nests do.
Species that build open nests tend to have larger ranges than species that build domed nests.
Step 1: Decode and Map the Passage
Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| "Although most songbirds build open, cupped nests, some species build domed nests with roofs that provide much more protection." |
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| "Many ecologists have assumed that domed nests would provide protection from weather conditions and thus would allow species that build them to have larger geographic ranges than species that build open nests do." |
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| "To evaluate this assumption, a research team led by evolutionary biologist Iliana Medina analyzed data for over 3,000 species of songbirds." |
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Provide Passage Architecture & Core Elements
Main Point: Researchers tested the common assumption that birds with domed nests have larger geographic ranges than those with open nests.
Argument Flow: The passage establishes that while most songbirds build open nests, some build more protective domed nests. Ecologists have long assumed this extra protection would allow domed-nest species to expand into larger geographic areas. To test this assumption, Medina and her team analyzed data from thousands of songbird species.
Step 2: Interpret the Question Precisely
What's being asked? Which research finding would most directly challenge the ecologists' assumption
What type of answer do we need? Evidence or data that would contradict the assumption that domed nests lead to larger geographic ranges
Any limiting keywords? "most directly challenge" - we need the finding that most clearly contradicts the assumption, and "the assumption in the underlined sentence" - specifically about domed nest species having larger ranges
Step 3: Prethink the Answer
- The assumption is that domed nests → better weather protection → larger geographic ranges
- To challenge this directly, we'd need evidence showing that this predicted relationship doesn't actually exist in nature
- The most direct challenge would be finding that open-nest species actually have larger ranges than domed-nest species - the exact opposite of what the assumption predicts
Species that build open nests tend to have higher extinction rates than species that build domed nests.
- This finding about extinction rates doesn't address geographic range size at all
- While higher extinction rates might be related to geographic factors, this doesn't directly challenge the assumption about range size
Species that build open nests tend to be smaller in size than species that build domed nests.
- Body size differences between the species don't directly relate to geographic range size
- This finding could coexist with the assumption - small birds with open nests could still have smaller ranges than large birds with domed nests
Species that build open nests tend to use fewer materials to build their nests than species that build domed nests do.
- Information about nest construction materials doesn't challenge the assumption about geographic ranges
- The assumption is based on the protective function of domed nests, not the amount of materials used
Species that build open nests tend to have larger ranges than species that build domed nests.
- This directly contradicts the assumption by showing the opposite pattern - open nest species have larger ranges
- If open-nest species have larger ranges despite having less protection, this completely undermines the logic that domed nests should provide a range advantage