It has long been thought that humans first crossed a land bridge into the Americas approximately 13,000 years ago. _______...
GMAT Expression of Ideas : (Expression) Questions
It has long been thought that humans first crossed a land bridge into the Americas approximately 13,000 years ago. _______ based on radiocarbon dating of samples uncovered in Mexico, a research team recently suggested that humans may have arrived more than 30,000 years ago—much earlier than previously thought.
Which choice completes the text with the most logical transition?
Step 1: Decode and Map the Passage
Part A: Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| 'It has long been thought that humans first crossed a land bridge into the Americas approximately 13,000 years ago.' |
|
| [MISSING TRANSITION] |
|
| 'based on radiocarbon dating of samples uncovered in Mexico, a research team recently suggested that humans may have arrived more than 30,000 years ago—much earlier than previously thought.' |
|
Part B: Provide Passage Architecture & Core Elements
Main Point: New research suggests humans arrived in the Americas much earlier than previously believed.
Argument Flow: The passage sets up a contrast between long-held scientific belief about when humans first arrived in the Americas and recent research that challenges this timeline with a much earlier date.
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 a clear logical relationship here. The first sentence establishes what scientists have 'long thought' - that humans arrived 13,000 years ago. The second sentence presents new research suggesting they arrived 30,000+ years ago, which contradicts the established view. We need a transition word that signals we're moving from the old belief to contradicting new evidence.
✗ Incorrect
- This signals cause and effect, but the new research isn't a result of the old belief; it's contradicting evidence.
✗ Incorrect
- This signals agreement, but we're seeing opposite findings, not similar ones.
✓ Correct
- This signals contrast, which perfectly fits our analysis. Shows that the new research contradicts the long-held belief.
✗ Incorrect
- This signals we're wrapping up, but we're introducing new contradictory evidence, not concluding.