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Capuchin Monkeys.

by sumittaneja009 » Mon Nov 17, 2008 1:24 am
Hi,

Need some help on the CR below:

Capuchin monkeys often rub their bodies with a certain type of millipede. Laboratory tests show that secretions from the bodies of these millipedes are rich in two chemicals that are potent mosquito repellents, and mosquitoes carry parasites that debilitate capuchins. Some scientists hypothesize that the monkeys rub their bodies with the millipedes because doing so helps protect them from mosquitoes.

Which of the following, if true, provides the most support for the scientists’ hypothesis?

A. A single millipede often gets passed around among several capuchins, all of whom rub their bodies with it.
B. The two chemicals that repel mosquitoes also repel several other varieties of insects.
C. The capuchins rarely rub their bodies with the millipedes except during the rainy season, when mosquito populations are at their peak.
D. Although the capuchins eat several species of insects, they do not eat the type of millipede they use to rub their bodies.
E. The two insect-repelling chemicals in the secretions of the millipedes are carcinogenic for humans but do not appear to be carcinogenic for capuchins.
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by slash » Mon Nov 17, 2008 2:12 am
Im not sure about the option which Im gonna choose, but still wanted to try.

I go with option C

Scientists hypothesize that the monkeys rub their bodies with the millipedes because doing so helps protect them from mosquitoes.

A. A single millipede often gets passed around among several capuchins, all of whom rub their bodies with it.
Millipede are developed in the Capuchin monkeys and not passed through among them. Moreover it does not support the argument.

B. The two chemicals that repel mosquitoes also repel several other varieties of insects.
Repel other insects does not support the argument.

C. The capuchins rarely rub their bodies with the millipedes except during the rainy season, when mosquito populations are at their peak.
This do support the argument, in rainy season mosquito will be high in numbers and capuchins rub during the season.

D. Although the capuchins eat several species of insects, they do not eat the type of millipede they use to rub their bodies.
Not eating the type of millipede does not support the argument and it is irrelevant.

E. The two insect-repelling chemicals in the secretions of the millipedes are carcinogenic for humans but do not appear to be carcinogenic for capuchins.
This is option is tempting one to choose but I feel this is not the right answer. It has information which is not relevant to the argument. Carcinogenic to humans and not to Cauchins, this one no where supports the argument.
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by slash » Mon Nov 17, 2008 2:12 am
Im not sure about the option which Im gonna choose, but still wanted to try.

I go with option C

Scientists hypothesize that the monkeys rub their bodies with the millipedes because doing so helps protect them from mosquitoes.

A. A single millipede often gets passed around among several capuchins, all of whom rub their bodies with it.
Millipede are developed in the Capuchin monkeys and not passed through among them. Moreover it does not support the argument.

B. The two chemicals that repel mosquitoes also repel several other varieties of insects.
Repel other insects does not support the argument.

C. The capuchins rarely rub their bodies with the millipedes except during the rainy season, when mosquito populations are at their peak.
This do support the argument, in rainy season mosquito will be high in numbers and capuchins rub during the season.

D. Although the capuchins eat several species of insects, they do not eat the type of millipede they use to rub their bodies.
Not eating the type of millipede does not support the argument and it is irrelevant.

E. The two insect-repelling chemicals in the secretions of the millipedes are carcinogenic for humans but do not appear to be carcinogenic for capuchins.
This is option is tempting one to choose but I feel this is not the right answer. It has information which is not relevant to the argument. Carcinogenic to humans and not to Cauchins, this one no where supports the argument.
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by Jatinder » Mon Nov 17, 2008 3:16 am
slash wrote:Im not sure about the option which Im gonna choose, but still wanted to try.

I go with option C

Scientists hypothesize that the monkeys rub their bodies with the millipedes because doing so helps protect them from mosquitoes.

A. A single millipede often gets passed around among several capuchins, all of whom rub their bodies with it.
Millipede are developed in the Capuchin monkeys and not passed through among them. Moreover it does not support the argument.

B. The two chemicals that repel mosquitoes also repel several other varieties of insects.
Repel other insects does not support the argument.

C. The capuchins rarely rub their bodies with the millipedes except during the rainy season, when mosquito populations are at their peak.
This do support the argument, in rainy season mosquito will be high in numbers and capuchins rub during the season.

D. Although the capuchins eat several species of insects, they do not eat the type of millipede they use to rub their bodies.
Not eating the type of millipede does not support the argument and it is irrelevant.

E. The two insect-repelling chemicals in the secretions of the millipedes are carcinogenic for humans but do not appear to be carcinogenic for capuchins.
This is option is tempting one to choose but I feel this is not the right answer. It has information which is not relevant to the argument. Carcinogenic to humans and not to Cauchins, this one no where supports the argument.
As you emphasized C 2 times, it has to be correct :)
Keep flying
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by slash » Mon Nov 17, 2008 3:19 am
Sorry..I submit the post twice :)
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by ashish.arora » Mon Nov 17, 2008 4:54 am
Hi Slash,

Though I agree with most of the explanation you have provided, however, your explanation of D and E is not convincing. After reading the question, I find two options to be tempting:

C. The capuchins rarely rub their bodies with the millipedes except during the rainy season, when mosquito populations are at their peak.

Yes, this explains the analogy stated by the scientist since capuchins find the need to rub their bodies with the millipedes only in rainy season when mosquito's population is at peak. This is the only time when capuchins are most irritated by mosquitoes.

D. Although the capuchins eat several species of insects, they do not eat the type of millipede they use to rub their bodies.

Why this cannot be correct ?

Capuchins intentionally ignore eating millipes because they help them repelling mosquitos.

E. The two insect-repelling chemicals in the secretions of the millipedes are carcinogenic for humans but do not appear to be carcinogenic for capuchins.

How can this option be tempting. 'carcinogenic' means which can cause cancer. millipedes being carcinogenic to humans and not to capuchins could only give us an idea that capuchins are safe rubbing their body with milliped but gives no idea why they are doing so.

I think C is the answer because it seems to support more strongly as compared to D.
Last edited by ashish.arora on Tue Nov 18, 2008 12:45 am, edited 1 time in total.
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by schumi_gmat » Mon Nov 17, 2008 10:12 am
Hi Ashish,

D is wrong. Let me try to explain.

In strengthen questions, we do following -
1. Find an asssumtion to support the conclusion or fill in logical gap
2. eliminate faulty assumption.

Negate D. say they do eat the type of millipede they use to rub their bodies. Does this have any effect on the conclusion? No

Hence it is not a right assumption.

Hence answer is C.
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by ashish.arora » Tue Nov 18, 2008 12:47 am
I Agree with you. Thxs!!!
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Thanks!

by sumittaneja009 » Tue Nov 18, 2008 3:33 am
Thanks for your replies. I also feel C is the correct answer.

But the source from where i took this problem has the answer given as E. Does any one feel that E is the correct choice, if so please explain why?

Sumit
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by Carloblacksun » Tue Nov 18, 2008 4:36 am
I am quite sure that E is a mistake on your source. It should be C.
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by Karen » Tue Nov 18, 2008 12:44 pm
It's C, not E. C provides an additional link between the millipede-rubbing and the mosquitoes. To put it another way, someone who wants to say that they're NOT doing it to repel mosquitoes now has to explain two facts -- why they do it at all, and why the activity peaks just when the mosquito population peaks. So this strengthens the argument.

The observation that rubbing themselves with millipedes does not give capuchins cancer doesn't do anything to strengthen the link between the behavior and the idea of repelling mosquitoes.
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by cramya » Tue Nov 18, 2008 9:39 pm
Karen,
I see your explanation on how C) stengthens the argument but does it not contradict one of the facts given in the question?

Capuchin monkeys often rub their bodies is in the stem

Choice C) says Capuchin monkeys rarely rub their bodies

Is this ok ?

Regards,
Cramya
Last edited by cramya on Tue Nov 18, 2008 9:43 pm, edited 1 time in total.
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by Karen » Tue Nov 18, 2008 9:42 pm
Interesting observation about the word 'often' versus 'rarely'. I doubt this item is from the official sources, because they're usually careful about details like that. I didn't take the word 'often' so literally -- I just took it to mean it's something the monkeys are known to do, a well-established behavior, and then C just clarifies that actually, they don't do it so much all year around, but in a certain season they do it a lot.

ETA: Did the question about often versus rarely disappear while I was answering it? :) Actually, I thought it was a valid question about slightly sloppy wording on the part of whatever company produced the question.
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by cramya » Tue Nov 18, 2008 9:45 pm
Sorry I edited it as I could see where are you coming from on C) now but the question still lingers in my mind....

Is D) the decoy??
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by Karen » Wed Nov 19, 2008 6:18 am
What do you mean by decoy?
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