Atrens: An early entomologist observed ants carrying

Question

Atrens: An early entomologist observed ants carrying particles to neighboring ant colonies and inferred that the ants were bringing food to their neighbors. Further research, however, revealed that the ants were emptying their own colony’s dumping site. Thus, the early entomologist was wrong.

Atrens’s conclusion follows logically if which one of the following is assumed?

(A) Ant societies do not interact in all the same ways that human societies interact.

(B) There is only weak evidence for the view that ants have the capacity to make use of objects as gifts.

(C) Ant dumping sites do not contain particles that could be used as food.

(D) The ants to whom the particles were brought never carried the particles into their own colonies.

(E) The entomologist cited retracted his conclusion when it was determined that the particles the ants carried came from their dumping site.

Source: LSAT

KarishmaB · Accepted Answer

Entomologist observed ants carrying particles to neighbours and inferred that the ants were bringing food. 
Research revealed that the ants were emptying their own colony’s dumping site.

Atren's Conclusion: The early entomologist was wrong.

Let's try some pre-thinking. From the argument, it is obvious why the entomologist could be wrong. But how could he be right? What if the particles being carried from the dumping site WERE food particles? That is the only way he could be right.
So for Atren's conclusion to follow (that the entomologist was wrong), we need to assume that particles being carried were not food particles.

You don't have to get lost in the process. Sometimes, it could be s simple as asking yourself - what is the author assuming? He says that the entomologist is wrong so the ants were not carrying food so he is assuming that the particles at the dumping site are not food particles.

No other option makes sense.

Squib17 · Answer

Atrens: An early entomologist observed ants carrying particles to neighboring ant colonies and inferred that the ants were bringing food to their neighbors. Further research, however, revealed that the ants were emptying their own colony’s dumping site. Thus, the early entomologist was wrong.

The early entomologist had assumed that the ants are bringing food to the neighbors

Prethinking :  If the early entomologist is wrong then that is possible if the "particles" that ant are dumping at the neighbor colonies are NOT food/

Atrens’s conclusion follows logically if which one of the following is assumed?

(A) Ant societies do not interact in all the same ways that human societies interact.  This is irrelevant - we are not interested in knowing how ants interaction is different from humans ]

(B) There is only weak evidence for the view that ants have the capacity to make use of objects as gifts.  Out of scope - even if they make use of objects as gifts, how does that tell us, if the things dumped are not food?

(C) Ant dumping sites do not contain particles that could be used as food.  This should be the CORRECT answer - Because if this is true, then the conclusion of Atrens will be logical and the early entomologist's assumption that the ants bring food would be incorrect. ]

(D) The ants to whom the particles were brought never carried the particles into their own colonies. Irrelevant - What the ants did with the particles is not the concern here.

(E) The entomologist cited retracted his conclusion when it was determined that the particles the ants carried came from their dumping site.  This retraction does not mean that the particles carried were not food, which was the conclusion of the entomologist. The retraction could be because of some other reasons.

KB04 · Answer

Atrens: An early entomologist observed ants carrying particles to neighboring ant colonies and inferred that the ants were bringing food to their neighbors. Further research, however, revealed that the ants were emptying their own colony’s dumping site. Thus, the early entomologist was wrong.

Atrens’s conclusion follows logically if which one of the following is assumed?

Why would entomologist say that the particles that the ants were carrying were food particles? Because they thought that the dumping sites contained food items and that's how they inferred that the ants were bringing food to their neighbors.

BUT they were proved wrong that means we have to eliminate the possibility that the dumping sites contained food. That's exactly what C does. It eliminates the possibility that the dumping sites contained food particles and hence is our answer.

(A) Ant societies do not interact in all the same ways that human societies interact.
Comparing interactions of ants with that of human societies' interaction is absolutely out of scope.

(B) There is only weak evidence for the view that ants have the capacity to make use of objects as gifts.
What kind of gift are we talking about about, were they food particles or something else? who knows! Eliminate.

(D) The ants to whom the particles were brought never carried the particles into their own colonies.
Whether they carried the particles or didn't doesn't really matter and hence this option is out of scope too.

(E) The entomologist cited retracted his conclusion when it was determined that the particles the ants carried came from their dumping site.
Entomologists changed the mind. Who cares! Does it impact the argument? Absolutely not. Because our argument is based on the fact they said for the first time.

chesstitans · Answer

this source is from LSAT, i now realize how different LSAT is from GMAT.
C is the answer b/c it connects directly with the argument.
In LSAT, patterns in options are harder to recognize.

adkikani · Answer

generis nightblade354 pikolo2510 VeritasKarishma

I fell in to (D) for this question and would like to share my reasoning of argument and PoE.

Quote:

Atrens’s conclusion follows logically if which one of the following is assumed?

Start with question stem to know what is to be done after reading the argument.
This is clearly asking me to find the assumption.

Quote:

Atrens: An early entomologist observed ants carrying particles to neighbouring ant colonies and inferred that the ants were bringing food to their neighbours. Further research, however, revealed that the ants were emptying their own colony’s dumping site. Thus, the early entomologist was wrong.

Start with the conclusion:
the early entomologist was wrong.
Or
the early entomologist's claim was wrong.

entomologist: E
research : R

As per E, food = particles
Later research: no, actually ants dump whatever is in their colonies.
whatever: may or may not be food.

Let me also break down premise and counter-premise for better understanding:

An early entomologist observed ants carrying particles to neighbouring ant colonies
Fact/ premise

the ants were bringing food to their neighbours.
E's claim. Supporting premise for above fact

Further research revealed that the ants were emptying their own colony’s dumping site.
Counter premise for E's claim and main premise
supporting author's claim

Thus, the early entomologist was wrong.
Author(A) goes against E's claim with above premise

For a valid assumption to prove: E's claim is wrong:

a. We need to support A's claim
b. We need to defend against any weakener for E's claim
(b) is important since if there is a weakener then it would
invalidate E's claim

On argument text as this, I find it easier to simply negate the answer choices
to find the assumption instead of bridging gap between premise and conclusion.

For a moment, here is how I would prethink:
I need an answer choice that leads to claim:
food is not equal to particles
(y)
because if food = particles then the claim would be invalid.

Quote:

(A) Ant societies do not interact in all the same ways that human societies interact.

Incorrect comparison, the manner in which the ants interact: whether it is similar to humans or not
is outside the scope of argument.

Quote:

(B) There is only weak evidence for the view that ants have the capacity to make use of objects as gifts.

Underlined portion is way too out of scope. If in doubt, negate this choice:
There is a strong evidence for the view that ants have the capacity to make use of objects as gifts.
Is my claim that ants dump material in their own colonies affected? Nope.

Quote:

(C) Ant dumping sites do not contain particles that could be used as food.

I negated this to get:
Ant dumping sites do contain particles that could be used as food.
OK, so particles = food
What am I supposed to do?
to find an evidence that makes me invalidates my claim:
ants do carry food in terms of particles

I just got lost to think too much in my head and could not check how this fits.

Quote:

(D) The ants to whom the particles were brought never carried the particles into their own colonies.

Negate this, The ants to whom the particles were brought ALWAYS carried the particles into their own colonies

So let s say Ants carry particles from X to Z. This options talks about ants in Z.
It says ants in Z bring their own particles.
Then how can I say that other ants bring particles in to Z?
I selected this answer choice since I felt it supported A's claim

Quote:

(E) The entomologist cited retracted his conclusion when it was determined that the particles the ants carried came from their dumping site.

Whether E retracted from his conclusion after finding the new evidence is outside the scope of argument.

Overall, I think my approach faltered in pieces while connecting counter-premise to claim and
furthermore, when we are asked to prove: claim in invalid than to prove: claim is valid.
Not sure, if I am handling too many negatives in this question.

Let me know your approach to this question.

vasuca10 · Answer

Thanks a tonne for the explanation VeritasKarishma mam...

Just like adkikani I got too much lost in overthinking the answer choices and ended up marking incorrect answer choice

dave13 · Answer

Hey adkikani , i am not an expert, but since i answered the question correctly, here is my reasoning. i generally dont break any argument into premises, conclusions etc - i simply read an argument and use a common sense. My approach is called K.I.S.S. - Keep It Simple and Stupid.

Entomologist says that he saw ants carrying something to neighbour ants. Initially entomologist claimed that this "something" was food, but at the end of the day his obeservation turned out to be inaccurate. To understand why C is correct, you need to understand why D is incorrect. D says: (D) The ants to whom the particles were brought never carried the particles into their own colonies. Pay attention to word NEVER. when making an assumption avoid such extreme options unless there is HINT to word NEVER in the argument. You cant be sure of word NEVER in option C, since you dont know this information FOR SURE. now using POE you can easily pick C. well that was my reasoning

have a great day!

unraveled · Answer

Atrens: An early entomologist observed ants carrying particles to neighboring ant colonies and inferred that the ants were bringing food to their neighbors. Further research, however, revealed that the  ants were emptying their own colony’s dumping site . Thus, the early entomologist was wrong.

Atrens’s conclusion follows logically if which one of the following is assumed?

(A) Ant societies do not  interact  in all the same ways that human societies interact.

(B) There is  only weak evidence  for the view that ants have the capacity to make use of objects as gifts.

(C) Ant  dumping sites do not contain particles that could be used as food .

(D) The ants to whom the particles were brought  never carried the particles into their own colonies .

(E) The entomologist cited  retracted his conclusion  when it was determined that the particles the ants carried came from their dumping site.

In blue text the reasoning of the Atren is given based on which the conclusion that early entomologist was wrong was made. But what is the relation between emptying dumping site and food that ants carry. Early entomologist never in the passage mentioned that food was carried from dumping site and Atren never mentioned that food was carried from dumping site. Hence Atren suggests that dumping site could not have had food that ants carry.

Only B and C have some chance, others are irrelevant. 
B loses out since even a weak evidence tells us that ants carried gifts and that too if we consider food as gift.

Answer C.

Atrens: An early entomologist observed ants carrying

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Atrens: An early entomologist observed ants carrying

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