#16 - Must Be True

[Administrator]

Complete Question Explanation
(See the complete passage discussion here: lsat/viewtopic.php?t=10831)

The correct answer choice is (E)

This is a Passage Exclusivity question, which means that the answer choice will be one discussed in only one passage—in this case, passage A. In the first paragraph, the author of the first passage provides that conservationists used to be complacent, sharing Charles Elton’s view that disturbed habitats were the vulnerable ones, but that now they realize the wider threat, which includes pristine habitats.

Answer choice (A): Passage A does not mention research being limited to studying the economic impact of introduced species, so this cannot be the right answer to this Must Be True question.

Answer choice (B): Neither passage explores this topic.

Answer choice (C): Both authors mention that introduced species can lead to extinction, although neither specifies that “most ecologists” agree; it seems to be a fact. Regardless, it cannot be the right answer to this Passage Exclusivity question.

Answer choice (D): The author of passage A does not discuss general concerns prior to Elton, so this choice should be ruled out of contention.

Answer choice (E): This is the correct answer choice. As discussed in the first paragraph, the author provides that conservationists used to share Elton’s views, but that they no longer do.

[Khodi7531]

So I was debating a little on this question between C and E. I chose E, because it was clearly spoken about in A (and can be inferred in both passages since Ecologists don't believe in Eltons view, while it seems like passage B has a completely different view about how to approach/look at the situation). However C was tough for me to get rid of.

The way I was thinking to get rid of this:
I really didn't like "most agree" ....but knew passage B said "some" may be extinct. I wasn't sure if that was a big enough difference to say "Passage B doesn't talk about this, so I should get rid of it". So I looked to see fi it's supported in A, and didn't find it explicitly written but thought I found somewhat support all over. Just looking at the first paragraph I thought some things could be read like that (which can be a killer to think that optimistically, right?). Ultimately, most just seemed to be a stretch anyway I looked but was not at an ease of mind to let it go. What would have been the best way to get rid of this?

[Adam Tyson]

Exactly the way you did, khodi, by focusing on the extreme language in answer C and recognizing that while there is evidence to support that some ecologists would say that, we have no support for the claim that most would. It certainly seems reasonable to believe that, but the question is about explicit assertions rather than just implications. "Most" is what kills this answer! Well done!

[tetsuya0129]

Hi Powerscore staff,
By POE I got it right; however, I could not understand how Passage A "asserts" (E).

My paraphrase of what Elton mentions was:
(i) Elton views that disturbed habitats are most vulnerable to new arrival species.

Whereas in (E):
(ii) Elton views that new arrival species primarily threatens disturbed areas.

(i) states the disturbed habitats are very vulnerable to new arrivals, but it says nothing about whom new species primarily threatens. The disturbed habitat can be most vulnerable to new species even though the latter seldom threaten the former.

How could (i) and (ii) be deemed equivalent by the test maker?

[Robert Carroll]

tetsuya,

I think you're reading too much into "primarily threaten". If new arrivals don't threaten anything very much, Elton's view is still that the disturbed habitats are the ones most vulnerable. So, if we had to rank which habitats are threatened, would disturbed ones not be at the top of the list? I don't think "primarily threaten" means that the new arrivals threaten them most of the time, just that those are the habitats most threatened, or something similar. I think it's similar to the difference noted in this LR question: https://forum.powerscore.com/lsat/viewtopic.php?t=2375

Robert Carroll

[rightway1566]

I did not understand the distinction, or definition, in the first paragraph between "disturbed" and "pristine" habitats. To me, all habitats would be considered "disturbed" once non-native species are introduced to it, which is the overarching topic of both passages. I liked the first clause in answer E, but did not choose it because operating under my interpretation of the terms, I failed to see evidence for the ecologists to disagree with the idea that "disturbed" habitats were threatened.

Clearly I missed the definition of the scientific terms being used.

[Adam Tyson]

What you may be missing, rightway1566, is that the author is describing habitats as they are BEFORE a new species is introduced, and they contrast "disturbed habitats" (without clearly defining what those are) with "pristine, species-rich habitats." The implication is that disturbed habitats are those that are not pristine and species-rich. Perhaps they have been damaged by disease, or by human intervention such as development? Either way, Elton's view, shared by many others, was that disturbed habitats were the ones most vulnerable to new arrivals, but now ecologists (the ones the question is asking us about) believe that the pristine ones are just as vulnerable.

So, they aren't saying that the disturbed habitats are not threatened, but that new arrivals don't "primarily" threaten them. The threat is equal across habitats, not mainly one or the other.