QUESTION TEXT: Researcher: Over the course of three decades…
QUESTION TYPE: Paradox
PARADOX: Over three decades, the average beak size of wild birds shrunk. The average beak size of the captive birds stayed the same.
ANALYSIS: On paradox questions, open your mind and think about the situation. What are differences between wild and caged birds?
- Wild birds eat by themselves. Captive birds eat the food they’re given.
- Wild birds have to worry about predators.
I can think of other differences, but those two differences are the ones that seem relevant to beak sizes. Maybe food for wild birds has shrunk. Or maybe smaller beaks are needed to deal with a new predator.
After taking the time to form hypotheses, I immediately saw that C was the correct answer. Before thinking hard about any answer, I looked over all of them quickly to check if the prephrase was there.
___________
- This isn’t relevant. The stimulus was talking about the change in beak size over three decades. The captive population was captured three decades ago, and then observed. Starting beak size doesn’t matter – only change does.
- Same as A.
- CORRECT. This shows that the wild population faced selective pressure. More small beaked birds survived. Captive birds faced no such selective pressure.
- Body size doesn’t matter. I’m sure you’ve seen toucans, which have massive beaks but small bodies.
- So? This doesn’t tell us whether the researcher measured the beaks of captive birds more than once. We need a difference between the two populations.
Recap: The question begins with “Researcher: Over the course of three decades”. It is a Paradox question. To practice more Paradox questions, have a look at the LSAT Questions by Type page.
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Super says
For A and B, what if the responses are referring to how the researchers measured or determined that the average beak size changed or did not change?
TutorLucas (LSAT Hacks) says
Even if this were the case, it still wouldn’t explain the change in beak size over three decades. If, as these answer choices suggest, large-beaked birds are always easier to capture than small-beaked birds or vice versa, that doesn’t point to an explanation of why the beak size would have changed significantly over time.