Weaken: In 1960’s studies of rats, scientists found that crowding

Question

In 1960’s studies of rats, scientists found that crowding increases the number of attacks among the animals significantly. But in recent experiments in which rhesus monkeys were placed in crowded conditions, it was not such attacks that increased significantly, but rather instances of "coping" behavior, such as submissive gestures, avoidance of dominant individuals, and huddling with relatives. Therefore the evidence from rhesus monkeys makes it doubtful that crowding significantly increases aggressive impulses in primates.

Which of the following, if true, most seriously weakens the argument?

(A) The rhesus monkeys is the species of monkey that is more prone to fighting

(B) Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them

(C) All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions

(D) Some individual monkeys in the experiment were involved in more attacks than the others

(E) Some of the rhesus monkeys in the experiment were subjected to levels of crowding that are unlikely to occur in natural circumstances.

chetan2u · Accepted Answer

In 1960’s studies of rats, scientists found that crowding increases the number of attacks among the animals significantly. But in recent experiments in which rhesus monkeys were placed in crowded conditions, it was not such attacks that increased significantly, but rather instances of "coping" behavior, such as submissive gestures, avoidance of dominant individuals, and huddling with relatives. Therefore the evidence from rhesus monkeys makes it doubtful that crowding significantly increases aggressive impulses in primates.

Which of the following, if true, most seriously weakens the argument?

B. Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them

C. All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions

Hi,

the argument says that in rats, crowding led to more attacks on each other. But in a experiment with rhesus monkeys, # of attacks did not increase but 'coping behaviour' did.
Now the argument claims that crowding does not increase aggressive nature..

NOTE we are not talking of attacks but aggressive nature. - this should tell us that there MUST be something which happens amongst the monkeys which does not allow these aggressive nature to turn into ATTACKS..

lets see B and C.. 
B. Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them
 See the NOTE above. More the monkeys aggressive, more do other monkeys try to adjust to that by changing their behaviour so that the aggressive nature does not result into physical attacks...
this clearly WEAKENS the claim as the aggressive nature has increased but others have adopted a different approach to it..

C. All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions
 This would in a way STRENGTHEN the claim.....
The COPING behaviour is not common ONLY to crowded coditions but to uncrowded conditions too. This means that there is NO role played by aggressive attitude and hence MAY be the claim is correct

GMATNinja · Answer

Notice that the conclusion is about aggressive IMPULSES, not the number of attacks: "Therefore the evidence from rhesus monkeys makes it doubtful that crowding significantly increases  aggressive impulses  in primates. "

Because the number of attacks did not increase, the author concludes that aggressive impulses did not significantly increase. But what if aggressive impulses actually DID increase, and the monkeys simply adopted coping behavior to prevent those impulses from leading to actual attacks? In that case, aggressive impulses could have significantly increased even though the actual number of attacks did not increase.

Choice (B) explains this possibility, which goes against the author's reasoning.

Mbawarrior01 · Answer

Statement :  Rats > Crowding > Increased Aggression
 Rhesus Monkeys > Crowding > Does not increase aggression but instances of coping behavior

Conclusion :  Rhesus monkeys response to monkeys, applies to all monkeys.
 
Assumption :  Effect on Rhesus monkeys ---means---> Effect on all monkeys.
 
A. The rhesus monkeys is the species of monkey that is more prone to fighting.   Strengthens

B. Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them.   States the same

C. All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions
  This may weaken the argument. Hold it

D. Some individual monkeys in the experiment were involved in more attacks than the others   Out of scope

E. Some of the rhesus monkeys in the experiment were subjected to levels of crowding that are unlikely to occur in natural circumstances.   may be the one but "Some" makes it doubtful

IMO C, though not sure on this one. Waiting for OA.

adiagr · Answer

The argument cites evidence that a recent experiment shows that crowding resulted in increased instances of coping - submissive gestures. 
Based on this evidence argument concludes that crowding does not result in aggression.

Let us check each option and see which option weakens this argument. 
 
A. This does not relate to our main argument (what is the behaviour of rhesus monkeys when they are in a crowded atmosphere). Ignore this option.

B. This option discusses both key ideas: Coping behavior as well as aggression. Hold

C. Irrelevant to our argument. We have to discuss their behaviour in crowded conditions. Ignore this option.

D. Very subjective information. Not strong enough to support or weaken conclusion. Ignore this option.

E. Issue is not about contrasting this experiment with natural circumstances. Ignore this option.

By elimination also , B comes out as winner.

Let us quickly analyse it.

B says that Coping behaviour was infact an outcome to stop aggressive behaviour. So aggression was there and the submissive gestures were developed by group members for their protection. In light of this information, we cannot say that crowding does not cause aggression.

rahulkashyap · Answer

Not able to pick between b and c

daagh   chetan2u

Posted from my mobile device

Kurtosis · Answer

Argument: In rats, Crowding --> Aggressive behavior
But in rhesus monkeys, Crowding --> Coping behavior
So recent studies create a doubt on whether Crowding actually causes aggressive behavior

A. The rhesus monkeys is the species of monkey that is more prone to fighting - Incorrect - The rhesus monkeys may be prone to fighting but there is no relationship between crowding and aggressive behavior

B. Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them - Correct - Crowding causes aggressive behavior but coping behavior is used to mask the aggressive behavior.

C. All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions - Incorrect - Relationship is stated between coping behavior and uncrowded conditions. Not useful.

D. Some individual monkeys in the experiment were involved in more attacks than the others - Incorrect - Irrelevant

E. Some of the rhesus monkeys in the experiment were subjected to levels of crowding that are unlikely to occur in natural circumstances. - Irrelevant

Answer: B

rahulk28011 · Answer

how is B correct? When i see it, i see its strengthening than weakening. I found this question while giving my GMAT mock on GMAT Prep. While reviewing i found OA is B. Its bizarre and i cant understand, how B can be the right weakening option.

srikanth9502 · Answer

Conclusion ->  "The evidence from rhesus monkeys makes it doubtful that crowding significantly increases aggressive impulses in primates"

C. All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions

It states that the coping behaviour is observed in the normal conditions as well. This means that the crowding had no impact on the behaviour of the monkeys. 
So this option indeed strengthens the argument by implying that the crowding does not increase the aggressive impulses.

B. Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them.

This option implies that there is indeed a possibility of aggression and the monkeys had to alter their behaviour inorder to forestall such effect.

hassu13 · Answer

I understand that B is a weakener, C is a strengthener but I am unable to knock off D.
Can experts pl explain me how D is irrlevant. If some monkeys were involved in more attacks than the others then definitely the attacks did take place and attacks can logically take place because of aggression or aggressive impulses. This scenario, in turn, tends to weaken the conclusion.
Can someone pl correct me.

GMATNinja · Answer

Let's reconnect with the specific wording in the conclusion:

Now let's compare to the wording in (D):

The author concludes that it is doubtful that crowding has led to a significant, overall increase in aggressive impulses in primates.

Sure, we could weaken this conclusion by observing that there indeed has been a significant, overall increase in aggressive behavior among the rhesus monkeys. But this is not what choice (D) says.

(D) says that  some  monkeys were involved in more attacks  than other monkeys . This is a comparison between two groups of monkeys. It doesn't tell us anything about the overall level of attacks.

Furthermore, choice (D) focuses on  attacks , which (as we've discussed earlier in this thread) are not the same as  impulses .

For these two reasons, we can eliminate (D). I hope this helps!

mallya12 · Answer

How does option C strengthen the conclusion?

GMATNinja · Answer

To eliminate (C), we don't need to prove that it strengthens the conclusion -- we only need to prove that it does not WEAKEN the conclusion.

Take another look at (C):
 
The author uses evidence about rhesus monkey behavior in crowded conditions to make a claim about the aggressive impulses of primates in crowded conditions. So, how does this information about rhesus monkey behavior in  uncrowded  conditions affect the strength of that claim?

The answer is that we simply don't know. Maybe rhesus monkeys behave the same way in both crowded and uncrowded conditions, and maybe they don't. Because we have no way to know how the information in (C) impacts the author's conclusion, we can't say that it weakens the argument. (C) is out.

I hope that helps!

rnn · Answer

why is E incorrect?

(E) Some of the rhesus monkeys in the experiment were subjected to levels of crowding that are unlikely to occur in natural circumstances.

i was thinking on the lines that if the monkeys were in their natural circumstances this would have led to fighting but since they were test subjects this led to coping behaviour instead of fighting...

GMATNinja · Answer

There are a couple of issues with answer choice (E). First, take another look at the conclusion of the argument from the passage:
 
This conclusion makes a statement about how crowded conditions affect aggressive impulses in primates. It does not specific  how  these conditions came about, or if they are likely to occur in the wild. So, it is not relevant to consider whether the levels of crowding are likely to occur in natural circumstances -- it only matters what  does  happen to primates when they find themselves in crowded conditions.

Also, answer choice (E) tells us that "some" of the monkeys were subjected to unnaturally crowded conditions. Does "some" mean just a few of the monkeys, or a large minority, or half? We have no way of knowing what "some" really means in this context, so we cannot say how much it impacts the conclusion.

For these reasons, answer choice (E) does not "most seriously weaken" the argument.

I hope that helps!

napolean92728 · Answer

Correct Answer: (B) Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them.

Why B is correct: 
This option directly weakens the conclusion that "crowding doesn't significantly increase aggressive impulses in primates." If the monkeys developed coping behaviors specifically to prevent aggression that would otherwise occur due to crowding, then crowding actually does increase aggressive impulses - the monkeys are just managing these impulses through coping mechanisms. This undermines the core conclusion by suggesting that the lack of observed aggression doesn't mean aggressive impulses aren't present or increased.

Why other options are incorrect: 
 (A)  The rhesus monkey is the species of monkey that is more prone to fighting
This actually strengthens the argument. If rhesus monkeys are naturally more aggressive yet still didn't show increased attacks when crowded, it would further support the conclusion that crowding doesn't increase aggression in primates.
 (C)  All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions
This is irrelevant to the argument. The argument is based on the increase in coping behaviors in crowded conditions, not whether these behaviors exist in uncrowded conditions. The fact that these behaviors also occur elsewhere doesn't tell us anything about why they increased in the experiment.
 (D)  Some individual monkeys in the experiment were involved in more attacks than the others
This is too limited in scope. Individual variation in aggression doesn't address the overall pattern observed across the population. The argument is about whether crowding increases aggression in primates generally, not about variations among individuals.
 (E)  Some of the rhesus monkeys in the experiment were subjected to levels of crowding that are unlikely to occur in natural circumstances
This doesn't weaken the argument's conclusion about the relationship between crowding and aggression. The unnaturalness of the crowding levels doesn't explain away the observed pattern of increased coping rather than increased aggression.

agrasan · Answer

Hi experts  KarishmaB   GMATNinjaTwo   IanStewart   egmat 
Can we simply reject the option C on the basis of reasoning that knowing "coping behavior" in crowded or uncrowded conditions for rhesus monkeys doesn't help us know whether aggressive implulses will happen in primates or not. It's like knowing X for an event Y and commenting whether Y will happen or not. 
On the other hand, option B says that X (coping) happens because Y (aggression) happens, thus, creating a doubt on the argument's conclusion.

Please let me know if above reasoning is correct.

KarishmaB · Answer

Yes, exactly.

Look at the conclusion:  Therefore the evidence from rhesus monkeys makes it doubtful that crowding significantly increases aggressive impulses in primates.

It has nothing to do with coping, only to do with aggression. It says aggressive impulses do not increase in primates. We have to weaken it. So any option that doesn't address "aggression/aggressive impulses/fighting" in some way is irrelevant. We have to find an option that indicates that aggressive impulses may increase in primate too when crowded.

(B) Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them

This option says that coping behavior is adopted so that aggression doesn't increase. This implies that aggressive impulses may increase in crowds and hence the monkeys show coping behavior (stay close together and submissive) so that aggression doesn't actually take place.

(C) All the observed forms of coping behavior can be found among rhesus monkeys living in uncrowded conditions

Option (C) simply says that the same coping behavior is found in non crowded monkeys too. 
Well, that doesn't say anything about  aggressive impulses. Irrelevant.

Hence (B) works.

egmat · Answer

I can see you're working through this weaken question, and these can be tricky when they involve behavioral interpretations. Let me walk you through the key thinking process that'll help you crack this one.

Let's Break Down the Argument:

Notice what the author is doing here. The argument presents:
 
  Evidence about rats:  Crowding → significantly more attacks 
  Evidence about rhesus monkeys:  Crowding → more coping behaviors but NOT more attacks  
  Conclusion:  Therefore, the monkey evidence makes it doubtful that crowding significantly increases aggressive impulses in primates

Here's what you need to see: The argument assumes that because monkeys showed  coping behaviors  instead of attacks, this means they didn't have  aggressive impulses . That's a big logical leap!

So What Would Weaken This?

To weaken this argument, we need something that challenges the assumption that coping behaviors mean no aggressive impulses exist. Ask yourself: "What if the coping behaviors themselves indicate that aggressive impulses were present?"

Let's think about this strategically. The author interprets coping behaviors as evidence of  lack of aggression . But what if those coping behaviors were actually  responses to aggression ?

Why Answer Choice B Works:

Choice B tells us that "Coping behavior was adopted by the crowded monkeys to forestall acts of aggression among them."

This is a powerful weakener! Here's the logic:
 
 The argument assumes coping behaviors = no aggressive impulses 
 But if monkeys used coping behaviors to  prevent/forestall aggression , then aggressive impulses were actually present 
 The monkeys were just managing those impulses differently than rats did 
 Therefore, crowding DID increase aggressive impulses in the monkeys - they just handled them through coping instead of fighting

Think of it this way: If you're actively trying to prevent something, that thing must be a real threat. The coping behaviors don't indicate absence of aggression - they indicate the  presence  of aggression that needed to be managed.

Quick Check on Why Others Don't Work:

Choice A  doesn't weaken because even if rhesus monkeys are naturally aggressive, the study still showed they didn't increase attacks when crowded - this doesn't address whether aggressive impulses increased.

Choice C  is irrelevant because the key finding was that coping behaviors  increased significantly  under crowding, not that they were unique to crowded conditions.

Choices D and E  give us details about individual variation and crowding levels, but neither addresses the core reasoning flaw about what coping behaviors actually indicate about aggressive impulses.

The complete solution on Neuron breaks down the systematic framework for identifying assumptions in behavioral arguments and shows you the pattern recognition strategies that help you pre-think answers before even looking at the choices. You can find the detailed explanation for this question  here on Neuron  and understand the underlying patterns for weaken questions. Further, you can access comprehensive explanations for  similar official questions on Neuron  with practice quizzes and detailed analytics into your weaknesses.

Hope this helps you see the logic more clearly!

Weaken: In 1960’s studies of rats, scientists found that crowding

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Weaken: In 1960’s studies of rats, scientists found that crowding

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