QUESTION TEXT: Ecologist: Before finding a mate, male starlings…
QUESTION TYPE: Strengthen
CONCLUSION: The starlings’ decorations are used to attract females, and not to kill parasites.
REASONING: The male starlings stop decorating with green aromatic plants once egg laying starts.
ANALYSIS: Ah, the old bait and switch. Woo her with aromatic plants, and then, once she start laying eggs…..bam! Back to being a lazy male bird who doesn’t care about decorations.
Anyway, the ecologist has made a fairly convincing argument against parasites. If the males were trying to protect their young, they would probably keep deterring parasites while their young were being born.
But, interestingly, the ecologist hasn’t actually shown much evidence that attracting females is the cause, either. So, to strengthen the argument, we should find an answer that actually shows this is the reason.
___________
- So? This question says that parasites can harm nestlings. The competing theory was that the aromatic plants were used to protect nestlings, not to protect adults. So this answer does nothing to weaken that theory.
- This weakens the argument: it makes it seem that parasites actually are the cause. Perhaps parasite protection is only necessary before eggs are laid.
- This doesn’t really do anything. The ecologist’s point is that nests are not decorated with aromatic plants by males after egg laying starts.
- CORRECT. This helps show that females are the actual cause. When a female is near, decorations increase.
- This helps show that males could decorate their nests with aromatic compounds without harming nestlings. But, males don’t do such decorations, so this answer doesn’t really affect anything.
Recap: The question begins with “Ecologist: Before finding a mate, male starlings”. It is a Strengthen question. To practice more Strengthen questions, have a look at the LSAT Questions by Type page.
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MemberStratos says
Quick comment on (A): actually it rules out a potential alternative cause, that’s why it was tempting for me. The actual flaw of the argument is the fact that the ecologist jumps to a conclusion out of nowhere just by ruling out a hypothesis. Means we have to find an AC that either a) strengthens the rule-out of the initial hypothesis or b) shows further evidence for the conclusion or c) rules out other potential causes.
The problem I see with (A) is that, although it rules out another potential cause, it is not as strongly supporting the argument as (D), which actually fills the gap of the lacking evidence regarding why the hypothesis of attracting females should be correct.
FounderGraeme Blake says
I suppose A rules out the possibility that the aromatic plants serve to protect the adult females in the nests. Good point! The problem is the argument’s evidence already largely rules this out. If the males were laying down plants to protect females, why would they stop once the eggs are laid?
Note: This is an old comment but I wanted to clarify the point.