Q18 - Traditionally, students at Kelly University have evalu

[charmayne.palomba]

PT46, S3, Q18 (Analyze Argument (function))

(C) is correct.

This argument has a lot of moving parts. Our first task is to find the conclusion, and there are a couple candidates: the first sentence (that a maladaptive trait is unlikely to last long) and the second part of the last sentence (that those with maladaptive traits will be crowded out). Thinking about those two components, does one have to precede the other? It’s subtle, but in order for the trait to be eradicated from an animal population, those individuals carrying the trait must first be crowded out. Therefore, we should think of the first sentence as our conclusion"”a good reminder that the conclusion doesn’t always come at the end of the stimulus!

That’s a good start, but we have to sort through a pretty dense paragraph to figure out how the author is backing up the conclusion. To get a sense of how this argument comes together, let’s work backward, starting from the conclusion. As discussed above, the conclusion"”that a maladaptive trait is unlikely to persist"”is directly backed up by the fact that such traits are crowded out. Why? Because members of the population without the trait will survive and reproduce at a higher rate. Why? Because those lacking the trait will compete more successfully for resources. Let’s lay this out:

those without trait compete more successfully for resources

-->

survive and reproduce at higher rates

-->

maladaptive trait crowded out

-->

trait unlikely to persist in population


We’re asked about the first part; thus, (C) is the correct answer. The fact that individuals without the maladaptive trait will compete more successfully for resources is a premise supporting an intermediate conclusion (that those without the trait will survive and reproduce at higher rates.)

(A) This argument isn’t trying to discredit anything; it’s explaining why maladaptive traits are unlikely to last long in an animal population. We can eliminate this quickly.

(B) The main conclusion is a maladaptive trait won’t last long, so this is out.

(D) The conclusion relies on this evidence, so of course the argument isn’t trying to undermine it.

(E) If we’ve misunderstood the argument, this is a very tempting answer"”made more so by the fact that it’s located right in the middle of the stimulus! In order to determine whether this is an intermediate conclusion, we should ask ourselves whether it’s supported by a premise. If not, it can’t be an intermediate conclusion. The fact that some members lack the trait is not support for the fact that those that lack the trait will compete more successfully; it’s background information.

[goddished]

I'm having trouble understanding why this is a premise and not an intermediate conclusion. As far as my understanding, an intermediate conclusion is one that incorporates previous premises or definitions, rallying them toward a subsidiary conclusion that leads to the final conclusion (the thrust of the argument). A premise, on the other hand, should introduce new information.

In this case, the sentence "those lacking the trait will compete more successfully for the remaining resources" doesn't introduce any new information--the fact that some members will lack the trait is already stated by the preceding paragraph, and the fact that they will compete more successfully simply follows from the definition of "maladaptive." To my reading, this didn't introduce any new information, but merely synthesize information already included in the previous sentence--which should indicate an intermediary conclusion (given that the wider conclusion is given afterward and draws upon this).

I want to know why this analysis is wrong, so I can better identify what the LSAT writers want to call premises and what they want to call intermediate conclusions.

Thanks!