Monarch butterflies spend the winter hibernating on trees in certain

Question

Monarch butterflies spend the winter hibernating on trees in certain forests. Local environmental groups have organized tours of the forests in an effort to protect the butterflies’ habitat against woodcutters. Unfortunately, the tourists trample most of the small shrubs that are necessary to the survival of any monarch butterflies that fall off the trees. Therefore, the tour groups themselves are endangering the monarch butterfly population.

Which one of the following would it be most useful to know in evaluating the argument?

(A) the amount of forest land suitable for monarch butterfly hibernation that is not currently used by monarch butterflies for hibernation
(B) the amount of wood cut each year by woodcutters in forests used by monarch butterflies for hibernation
(C) the amount of plant life trampled by the tourists that is not necessary to the survival of monarch butterflies
(D) the proportion of the trees cut down by the woodcutters each year that are cut in the forests used by monarch butterflies for hibernation
(E) the proportion of hibernating monarch butterflies that fall off the trees

Source: LSAT

MyGuruStefan · Answer

On LSAT logical reasoning and GMAT critical reasoning, it is critical (pun intended!) that you pay close attention to any terms that shift between the presented grounds/evidence and the posited conclusion. In this case the "Monarch butterflies... hibernating on trees in certain forests" presented in the opening of the prompt subtly shifts to "monarch butterflies that fall of(f) the trees". By proactively identifying this slight shift in terms, it can be predicted that in order to evaluate the cogency of this argument it is imperative to learn whether "monarch butterflies... hibernating on trees in certain forests" = "monarch butterflies that fall of(f) the trees". This matches choice E.

Nijssen · Answer

Argument: butterflies hibernate on trees, environmentalists do tours of the forests in order to protect the butterflies’ habitat against woodcutters. But tourists trample butterflies that fall of the trees and thus endanger the butterflies themselves.

A Irrelevant to the evaluation of possible negative effects of the tours.
B Relevant to the negative effects of the woodcutters, but not to the tours.
C Irrelevant, because this has no effect on the survival of butterflies
D Same as B
 E Correct. If we know this we can determine the extent of the negative consequences of the tours

Kudos if helped.

nightblade354 · Answer

Bumping for further discussion! This is a good LSAT evaluate question that could you use more explanations.

risehazy05 · Answer

Is it "fall of the tree" or "fall off the tree"?

naveengmat15 · Answer

Why C is wrong ?
 KarishmaB   GMATNinja

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nikitathegreat · Answer

GMATNinja  -Please explain why Option C is wrong?

PJ226 · Answer

The point of the argument is that the tourists are endangering the monarch butterfly population. We want some information that will either strengthen or weaken that conclusion.

Option (C) will only help us know whether tourists destroy plant life that is not essential to the survival of the species in question.

Whether tourists destroy most of it or none at all, the information in option (C) is irrelevant at best.

yazlal25 · Answer

Please explain why E is the answer

MartyMurray · Answer

Monarch butterflies spend the winter hibernating on trees in certain forests. Local environmental groups have organized tours of the forests in an effort to protect the butterflies’ habitat against woodcutters. Unfortunately, the tourists trample most of the small shrubs that are necessary to the survival of any monarch butterflies that fall of the trees. Therefore, the tour groups themselves are endangering the monarch butterfly population.

The conclusion of the argument is the following:

the tour groups themselves are endangering the monarch butterfly population

The support for the conclusion is the following:

Unfortunately, the tourists trample most of the small shrubs that are necessary to the survival of any monarch butterflies that fall off the trees.

One aspect of the reasoning that we might notice is that the argument jumps from the fact that tourists trample shrubs necessary for the survival of butterflies that fall from trees to the conclusion that tourists are endangering the entire butterfly population.

Which one of the following would it be most useful to know in evaluating the argument?

This is an Evaluate question, and the information mentioned by correct answer will weaken or strengthen the argument.

(A) the amount of forest land suitable for monarch butterfly hibernation that is not currently used by monarch butterflies for hibernation

Information on the amount of land suitable for monarch butterfly hibernation does not help in evaluating the case for the conclusion of this argument.

After all, the conclusion is not about whether there's any possible way for monarch butterflies to survive. It's more specifically that tour groups are endangering the entire butterfly population.

Regardless of whether there's much or little other land on which monarchs could hibernate, the actions of tourists on the land on which the butterflies are in fact hibernating may or may not be endangering the population.

Eliminate.

(B) the amount of wood cut each year by woodcutters in forests used by monarch butterflies for hibernation

This information could indicate whether the monarch population is endangered by woodcutters.

At the same time, the conclusion of the argument is that tour groups are endangering the population.

Information on what woodcutters do does not indicate whether tourists are endangering the population.

Eliminate.

(C) the amount of plant life trampled by the tourists that is not necessary to the survival of monarch butterflies

Tourists trampling plant life may not be a great thing. At the same time, this information has no effect on the case for the conclusion of this argument.

After all, regardless of whether the amount of plant life not necessary to the survival of monarch butterflies tourists trample is large or small, that information doesn't indicate whether tourists are endangering the monarch butterfly population since monarch survival doesn't depend on that plant life.
Eliminate.

(D) the proportion of the trees cut down by the woodcutters each year that are cut in the forests used by monarch butterflies for hibernation

This information could indicate whether the monarch population is endangered in general.

At the same time, the conclusion of the argument is not simply that the population is endangered. Rather, it's that tour groups are endangering the population.

Information on what woodcutters do does not indicate whether tourists are endangering the population.

Eliminate.

(E) the proportion of hibernating monarch butterflies that fall off the trees

This choice is interesting.

After all, the argument uses the fact that "tourists trample most of the small shrubs that are necessary to the survival of any monarch butterflies that fall of the trees, to support the conclusion that "the tour groups themselves are endangering the monarch butterfly population."

We can see that, if the proportion of hibernating monarch butterflies that fall off the trees is very small, then it's unlikely that tourists are endangering the entire monarch butterfly population by trampling the shrubs. On the other hand, if the proportion of hibernating butterflies that fall off the trees is very large, then it's likely that tourists are endangering the population by trampling the shrubs.

After all, if, for instance, 90 percent of hibernating butterflies fall from trees and therefore need the shrubs to survive, then the tourists' actions are making the survival of almost the entire population unlikely.

So, the information mentioned by this choice affects the strength of the argument by indicating the degree to which it's true that, by trampling the shrubs, tour groups are endangering the population.

Keep.

Correct answer:   E

yazlal25 · Answer

Many thanks Marty for your detailed explanation.

Monarch butterflies spend the winter hibernating on trees in certain

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Monarch butterflies spend the winter hibernating on trees in certain

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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