LSAT 104 | Section 1 | Logical Reasoning: Q4

LR Question 4 Explanation

QUESTION TEXT: In Yasukawa’s month-long study of blackbirds, the…

QUESTION TYPE: Weaken

CONCLUSION: Yasukawa’s research is probably wrong. He said that size affects death rates.

REASONING: Larger birds are older.

ANALYSIS: The main (implied) criticism was that larger birds die more often because they are older. The right answer shows that larger birds aren’t necessarily older: they’re from a different species.

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1. CORRECT. This is tricky. The critics said larger birds are older. This answer choice shows that probably wasn’t true. Instead, larger birds are a different species.
    
   We still don’t know why larger birds died faster. Maybe it was size, or maybe that species just has a lower life expectancy. But we don’t need to know why: this answer choice shows the critics misunderstood the experiment. They thought the birds were all the same species, and size was proof of age.
2. It’s a good idea to examine a species in the wild. In fact, it was to be expected that this experiment studied wild birds. So this can hardly weaken the critics; they probably expected Yasukawa studied wild birds.
3. Why would anyone expect Yasukawa to compare blackbirds to other birds? Certainly, the critics didn’t mention that, so this can’t hurt them.
4. This is very vague. “More” could mean large birds are .00001% more successful than smaller birds. And we don’t know how many fights there were. And we don’t know if fights are fatal, or what consequences they have, etc.
    
   In short, this answer tells us nothing concrete. Even if it did, I’m not sure how it would weaken the critics.
5. Everything I said in D applies here. We have no idea how strong this effect was, and how important social hierarchies are, and what effect they have on death rates.

Recap: The question begins with “In Yasukawa’s month-long study of blackbirds, the”. It is a Weaken question. Learn more about LSAT Weaken questions in our guide to LSAT Logical Reasoning question types.