Marine biologists had hypothesized that lobsters kept together

Question

Marine biologists had hypothesized that lobsters kept together in lobster traps eat one another in response to hunger. Periodic checking of lobster traps, however, has revealed instances of lobsters sharing traps together for weeks. Eight lobsters even shared one trap together for two months without eating one another. The marine biologists’ hypothesis, therefore, is clearly wrong.

The argument against the marine biologists’ hypothesis is based on which one of the following assumptions?

(A) Lobsters not caught in lobster traps have been observed eating one another.

(B) Two months is the longest known period during which eight or more lobsters have been trapped together.

(C) It is unusual to find as many as eight lobsters caught together in one single trap.

(D) Members of other marine species sometimes eat their own kind when no other food sources are available.

(E) Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger.

Source: LSAT

Bunuel · Accepted Answer

OFFICIAL EXPLANATION

(A) No. The argument is concerned only with trapped lobsters.

(B) No. If this choice were false—i.e., if two months was not the longest known period eight or more lobsters were trapped together—the conclusion would
not be weakened.

(C) No. This is irrelevant.

(D) No. This is irrelevant—the argument is only about lobsters.

(E) Yes.  Perhaps food drifted into the cage from a current, or perhaps other creatures that the lobsters feed on entered the cage. To be valid, the argument must assume that any food which entered the cage was not sufficient to satisfy the lobsters’ hunger.

sidd13 · Answer

Marine biologists had hypothesized that lobsters kept together in lobster traps eat one another in response to hunger. Periodic checking of lobster traps, however, has revealed instances of lobsters sharing traps together for weeks. Eight lobsters even shared one trap together for two months without eating one another. The marine biologists’ hypothesis, therefore, is clearly wrong.

The argument against the marine biologists’ hypothesis is based on which one of the following assumptions?

(A) Lobsters not caught in lobster traps have been observed eating one another.

(B) Two months is the longest known period during which eight or more lobsters have been trapped together.

(C) It is unusual to find as many as eight lobsters caught together in one single trap.

(D) Members of other marine species sometimes eat their own kind when no other food sources are available.

(E) Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger.

The answer is E and the explaination for the same is

And while I'm guilty of this myself many times in the past, let me try to be very precise in how the Negation Test works. It's not that the negation of the correct answer will destroy the conclusion, but that it makes it so the conclusion does not follow from the evidence offered. So after negating answer choice (E), the conclusion that lobsters do not eat one another in response to hunger may still be true, but we would not be able to use the evidence provided to support such a conclusion. An assumption of this argument is that the lobsters were in fact hungry. Without that assumption the example of the lobsters would be irrelevant to a claim about what happens to lobsters in response to hunger. Answer choice (E) simply provides this assumption.

Let's take a look at the incorrect answer choices:

(A) undermines the argument that lobsters will not each other in response to hunger.
(B) is irrelevant. Two months is more than enough time to allow a lobster to become hungry, and if it wasn't, that would again simply undermine the argument.
(C) is irrelevant. The frequency with which lobsters are caught in large groups plays no role in what happens once they are.
(D) is tempting in that it suggests the behavior is common at least on other marine species, but while it helps, it is not a Necessary Assumption of the argument.

sandeep211986 · Answer

I will go with option E.
Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger.

Negate that:

Any food that the eight lobsters in the trap might have obtained WAS enough to ward off hunger.

When you negate that answer choice and have it say that the lobsters might have obtained food that was enough to keep away hunger. This would destroy the conclusion of the counter to the marine biologists.

Regards,
Sandeep
Kudos please.

septwibowo · Answer

After reading this argument, I felt that this conclusion has the gap..   So, two months mean that lobsters are suffered from hunger?
  
Answer E clearly bridging the gap. Yes, they are hungry! So, why they don't eat one another? --> The conclusion, then, IS WRONG.

Wdyt?

gmatexam439 · Answer

Marine biologists had hypothesized that lobsters kept together in lobster traps eat one another in response to hunger. Periodic checking of lobster traps, however, has revealed instances of lobsters sharing traps together for weeks. Eight lobsters even shared one trap together for two months without eating one another. The marine biologists’ hypothesis, therefore, is clearly wrong.

The argument against the marine biologists’ hypothesis is based on which one of the following assumptions?

(A) Lobsters not caught in lobster traps have been observed eating one another. - Out of scope

(B) Two months is the longest known period during which eight or more lobsters have been trapped together. - Doesn't matter. It doesn't tell us as to why the lobsters don't eat each other

(C) It is unusual to find as many as eight lobsters caught together in one single trap. - out of scope

(D) Members of other marine species sometimes eat their own kind when no other food sources are available. - Lobsters? This would in a way strengthen biologist's argument

(E) Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger. - Correct

David nguyen · Answer

Marine biologists had hypothesized that lobsters kept together in lobster traps eat one another in response to hunger. Periodic checking of lobster traps, however, has revealed instances of lobsters sharing traps together for weeks. Eight lobsters even shared one trap together for two months without eating one another. The marine biologists’ hypothesis, therefore, is clearly wrong.

MB: lobster eat each other when trapped in response to hunger
Author: MB is wrong. 8 lobsters did not eat each other in the same trap for 2 months.

What is the missing link here? Author's argument based on the fact that the lobsters did not eat each other without any other concern explicitly stated. MB claimed that the lobsters eat each other in response to HUNGER. Author's conclusion must connect this point with his premise; it has to do something with HUNGER.

The argument against the marine biologists’ hypothesis is based on which one of the following assumptions?

The situation is when the lobsters are TRAPPED and HUNGRY.(A) is out.
 
Trapped time is irrelevant. The argument is only concerned about whether cannibalism exists. (B) is out.
 
Whether it is unusual or not, does it affect the argument in any ways? No? (C) is out.
 
Other species do not matter here. LOBSTER is the main point. (E)
 
This proves that the lobsters were not brutal. They spared each other's life. Nice play, lobsters! Cheer to the correct answer (E), which is the only remaining choice as well.

unraveled · Answer

Marine biologists had hypothesized that lobsters kept together in lobster traps eat one another in response to hunger. Periodic checking of lobster traps, however, has revealed instances of lobsters sharing traps together for weeks. Eight lobsters even shared one trap together for two months without eating one another. The marine biologists’ hypothesis, therefore, is clearly wrong.

The argument against the marine biologists’ hypothesis is based on which one of the following assumptions?

(A) Lobsters not caught in lobster traps have been observed eating one another.

(B) Two months is the longest known period during which eight or more lobsters have been trapped together.

(C) It is unusual to find as many as eight lobsters caught together in one single trap.

(D) Members of other marine species sometimes eat their own kind when no other food sources are available.

(E) Any food that the eight lobsters in the trap might have obtained was not enough to ward off hunger.

Eight lobsters didn't eat each other was amusing to author since as per marine biologists hypothesis they must have eaten each other out of hunger. Based on this author claims that marine biologist's claim is wrong. Thus, author thinks that lobsters were hungry in that trap for two months. If they were not hungry the argument dies here itself. So, they must be hungry to prove the point otherwise(as per author). And how this is possible, by lobsters remaining hungry in that trap. Then how they remain hungry, by eating whatever they had in that trap which eventually didn't end their hunger. This happened only when the food they got was not enough.

E gives us this ans is the right answer.

VerbalBot · Answer

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Marine biologists had hypothesized that lobsters kept together

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