Text 1Fossils of the hominin Australopithecus africanus have been found in the Sterkfontein Caves of South Africa, but assigning an...
GMAT Craft and Structure : (Structure) Questions
Fossils of the hominin Australopithecus africanus have been found in the Sterkfontein Caves of South Africa, but assigning an age to the fossils is challenging because of the unreliability of dating methods in this context. The geology of Sterkfontein has caused soil layers from different periods to mix, impeding stratigraphic dating, and dates cannot be reliably imputed from those of nearby animal bones since the bones may have been relocated by flooding.
Text 2
Archaeologists used new cosmogenic nuclide dating techniques to reevaluate the ages of A. africanus fossils found in the Sterkfontein Caves. This technique involves analyzing the cosmogenic nucleotides in the breccia—the matrix of rock fragments immediately surrounding the fossils. The researchers assert that this approach avoids the potential for misdating associated with assigning ages based on Sterkfontein's soil layers or animal bones.
Based on the texts, how would the researchers in Text 2 most likely respond to the underlined portion in Text 1?
They would emphasize the fact that the A. africanus fossils found in the Sterkfontein Caves may have been corrupted in some way over the years.
They would contend that if analyses of surrounding layers and bones in the Sterkfontein Caves were combined, then the dating of the fossils there would be more accurate.
They would argue that their techniques are better suited than other methods to the unique challenges posed by the Sterkfontein Caves.
They would claim that cosmogenic nuclide dating is reliable in the context of the Sterkfontein Caves because it is applied to the fossils directly.
Looking at this Cross-Text Connections question, I need to understand how the researchers in Text 2 would respond to the dating challenges described in Text 1. Let me work through this systematically.
Step 1: Decode and Map the Passage
Part A: Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| Text 1: "Fossils of the hominin Australopithecus africanus have been found in the Sterkfontein Caves of South Africa" |
|
| "but assigning an age to the fossils is challenging because of the unreliability of dating methods in this context." |
|
| "The geology of Sterkfontein has caused soil layers from different periods to mix, impeding stratigraphic dating" |
|
| "and dates cannot be reliably imputed from those of nearby animal bones since the bones may have been relocated by flooding." |
|
| Text 2: "Archaeologists used new cosmogenic nuclide dating techniques to reevaluate the ages of A. africanus fossils found in the Sterkfontein Caves." |
|
| "This technique involves analyzing the cosmogenic nucleotides in the breccia—the matrix of rock fragments immediately surrounding the fossils." |
|
| "The researchers assert that this approach avoids the potential for misdating associated with assigning ages based on Sterkfontein's soil layers or animal bones." |
|
Part B: Passage Architecture & Core Elements
Text 1: PROBLEM - A. africanus fossils found in Sterkfontein. Dating is challenging because: Mixed soil layers block stratigraphic dating. Animal bones unreliable (flooding moved them).
Text 2: SOLUTION - New cosmogenic nuclide dating technique. Analyzes breccia around fossils. Researchers claim: avoids soil layer + animal bone problems.
Main Point: Text 1 identifies specific dating challenges for Sterkfontein fossils, while Text 2 presents a new technique that researchers claim solves those exact challenges.
Step 2: Interpret the Question Precisely
What's being asked? How would the Text 2 researchers respond to the underlined portion in Text 1 (the part about dating being challenging due to unreliable methods).
What type of answer do we need? The researchers in Text 2 developed their cosmogenic nuclide technique specifically to address the dating problems described in Text 1. They explicitly claim their approach "avoids the potential for misdating associated with assigning ages based on Sterkfontein's soil layers or animal bones" - which are exactly the two challenges mentioned in the underlined portion.
Any limiting keywords? None
Step 3: Prethink the Answer
- Text 1 identifies specific dating challenges for Sterkfontein fossils
- Text 2 presents a new technique that researchers claim solves those exact challenges
- The researchers developed cosmogenic nuclide dating specifically to address the dating problems described in Text 1
- They explicitly claim their approach "avoids the potential for misdating associated with assigning ages based on Sterkfontein's soil layers or animal bones"
- These are exactly the two challenges mentioned in the underlined portion
They would emphasize the fact that the A. africanus fossils found in the Sterkfontein Caves may have been corrupted in some way over the years.
✗ Incorrect
- This focuses on fossil corruption over time
- Text 2 doesn't mention anything about the fossils themselves being corrupted
- The researchers are addressing dating method problems, not fossil preservation issues
They would contend that if analyses of surrounding layers and bones in the Sterkfontein Caves were combined, then the dating of the fossils there would be more accurate.
✗ Incorrect
- Suggests combining the problematic methods would improve accuracy
- This contradicts the researchers' approach - they're replacing the problematic methods, not combining them
They would argue that their techniques are better suited than other methods to the unique challenges posed by the Sterkfontein Caves.
✓ Correct
- Matches exactly what the researchers claim in Text 2
- They developed cosmogenic nuclide dating specifically for Sterkfontein's unique challenges (mixed soil layers, relocated bones)
- Their assertion that the technique "avoids the potential for misdating" directly responds to Text 1's "unreliability of dating methods"
They would claim that cosmogenic nuclide dating is reliable in the context of the Sterkfontein Caves because it is applied to the fossils directly.
✗ Incorrect
- Claims the technique is applied to fossils directly
- Text 2 clearly states they analyze the "breccia" (rock matrix around fossils), not the fossils themselves