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# Bumblebees OG 2016 In Colorado subalpine meadow

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12 Jul 2015, 03:37
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In Colorado subalpine meadows, nonnative dandelions co-occur with a native ﬂower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed rom eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Which of the following, if true, most seriously undermines the researchers’ reasoning?

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.

(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.

(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.

(D) Seed germination is a more reliable measure of a species’ ﬁtness than seed production.

(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

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27 Aug 2015, 04:14
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In Colorado subalpine meadows, nonnative dandelions co-occur with a native ﬂower, the larkspur.
P1: Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination.
In a recent study, researchers selected 16 plots containing both species; all dandelions were removed ﬁom eight plots; the remaining eight control plots were left undisturbed.

P2:The control plots yielded significantly more larkspur seeds than the dandelion-free plots,
leading the researchers to conclude that
the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Assumption: dandelions absence is the only reason for cause.
Any other factor that can lead to same behavior can be used as a weakener.

Which of the following, if true, most seriously undermines the researchers’ reasoning?

A. Bumblebees preferentially visit dandelions over larkspurs in mixed plots.
B. In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
>> Looking at premise, I feel this is in line with argument. Ignore.

C. If left unchecked, nonnative species like dandelions quickly crowd out native species.
D. Seed germination is a more reliable measure of a species’ ﬁtness than seed production.
>>Irrelevant.

E. Soil disturbances can result in fewer blooms, and hence lower seed production.
>> By POE; As per premise, the plots that were left undisturbed gave good yield. So plot disturbed == soil disturbed.
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10 Sep 2015, 06:39
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In Colorado subalpine meadows, nonnative dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Which of the following, if true, most seriously undermines the researchers’ reasoning?

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.
(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.
(D) Seed germination is a more reliable measure of a species’ fitness than seed production.
(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

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10 Sep 2015, 11:23
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amatya wrote:
In Colorado subalpine meadows, nonnative dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.
Which of the following, if true, most seriously undermines the researchers’ reasoning?

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.
(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.
(D) Seed germination is a more reliable measure of a species’ fitness than seed production.
(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

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Dear amatya,
I'm happy to help. As always, this OG question is a great question!

The scientists concluded that "the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots." We want to weaken this conclusion.

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.
If all the bees were visiting dandelions, then this would not explain why the larkspurs got so pollinated, producing a great quantity of seeds. This is simply inconsistent with the evidence. This is not correct.

(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
This is a strengthener. If this is true, then it would explain why having dandelions in the plot would result in more pollination for the larkspurs. This is a typical GMAT CR trap, having a strengthener for a weakener, or vice versa. This is not correct.

(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.
This is a problems down the road, a reason why in the big picture dandelions might be a problem for larkspars, but it doesn't do anything to address the issue of which plants get pollinated and how many seeds are produced. This is not correct.

(D) Seed germination is a more reliable measure of a species’ fitness than seed production.
Even if this is true, it is not relevant, because in terms of the experiment, only seed production was measured. There was no measurement of seed germination: at most, it was merely inferred from seed production. The experiment left no means to distinguish between these two, so the distinction in this context is experimentally meaningless. This is incorrect.

(E) Soil disturbances can result in fewer blooms, and hence lower seed production.
This may appear irrelevant at first glance, but think about it. The control plot (with dandelions) produced more seeds than the experimental, dandelion-free plot. How was that latter plot prepared? The prompt says: "all dandelions were removed from eight plots." In other words, all the dandelions were ripped out, disturbing the soil. According to this answer choice, this soil disturbance would have inhibited seed production in the control group. This provides an alternative explanation to the experimental results: according to this view, the fact that the control group had more seeds than the experimental group has nothing to do with the presence or absence of dandelions, but with the presence or absence of soil disturbance. Providing a cogent alternative explanation shatters the reliability of the argument. This is a weakener.

(E) has to be the OA. This is a brilliant question, because at first glance, it may appear that (E) is entirely out-of-scope and irrelevant. You have to think about the details of the prompt to recognize why it is so relevant.

Does all this make sense? Here's a blog with more thoughts about weakening arguments:
https://magoosh.com/gmat/2012/how-to-we ... reasoning/

Mike
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21 Sep 2015, 22:25
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In Colorado subalpine meadows, nonnative dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Which of the following, if true, most seriously undermines the researchers' reasoning?

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.

(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.

(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.

(D) Seed germination is a more reliable measure of a species' fitness than seed production.

(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

Type: Weaken
Boil It Down: Dandelions removed, larkspur down -> Dandelions boost pollination of native
Missing Information: Were there other factors?
Goal: Find the option that shows that the difference in pollination between the two groups in the study is not about the presence of dandelions.

A) This option doesn't weaken for two reasons: 1) A preference doesn't necessarily mean that bumblebees still wouldn't visit both plants 2) The option flat out doesn't weaken the argument. In fact, if anything it appears to have the flavor of a strengthener since a preference toward dandelions would seem to support the findings of the study that dandelions are luring bumblebees to native plants.

B) This option would also appear to strengthen the argument that the presence of dandelions boosts pollination of native plants since this option would suggest that pollination is enhanced in mixed plots (those that include dandelions).

C) Overcrowding could very well occur, but that wouldn't weaken the claim that the presence of dandelions still boosts native plant production. Gone.

D) This option centers on the measurement of species fitness, but species fitness is a completely different topic. This option is completely Out of Focus.

E) Yes! Here we have an option that directly offers an alternative explanation. The difference in pollination in the study wasn't the presence of dandelions (or the lack of them) but rather the fact that the removal of the dandelions in the study disrupted blooms, and thus pollination. This option exposes the dark truth that this study is miserably flawed.
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04 Nov 2015, 15:55
Mike, amazing explanation.

I thought at first no way E is correct, it's totally irrelevant. Another great lesson. The key is as always in thorough understanding of the conclusion.

Thank you,
Jay

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05 Nov 2015, 21:55
Straight E. In such questions, the first assumption comes to the mind will be , two sets must be comparable in any sense. If there is a difference of any condition , we get weakening point.

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03 Feb 2016, 03:24
In my opinion, this is a argument with many difficult biological word.
The logic behind is easy and conclusion is easy to understand as well.
Thus i propose to adjust the difficulty level from 95% to 55%.

But it is purely up to your choices.

sorry, now i want to say this is a good question as i didn't notice the tricky part.

Last edited by newconcept123 on 17 Feb 2016, 09:16, edited 1 time in total.

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03 Feb 2016, 04:33
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Dear Concep123,

Your post could be much better if you would have explained "Why the logic behind the question is too easy"??

It may be "too easy" for you, I am not sure.

I think the question difficulty is decided automatically based on number of sessions and accuracy levels.

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17 Apr 2016, 18:57
mikemcgarry wrote:

Does all this make sense? Here's a blog with more thoughts about weakening arguments:
https://magoosh.com/gmat/2012/how-to-we ... reasoning/

Mike

I like all the questions from GMAC. Usually I do not doubt them at all.
But, For some reason - I did not like this question. Reason: The argument expects us to think that soil disturbances might have occurred when dandelions were removed. This is okay, but there could be plenty of other possibilities that could have occurred and be linked to the question as well.

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18 Apr 2016, 01:54
you are right rachitshah that "there could be
plenty of other possibilities that could have occurred
and be linked to the question as well."

But this possibility is one of the many. right?
So why border?

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18 Apr 2016, 15:56
rachitshah wrote:
mikemcgarry wrote:

Does all this make sense? Here's a blog with more thoughts about weakening arguments:
https://magoosh.com/gmat/2012/how-to-we ... reasoning/

Mike

I like all the questions from GMAC. Usually I do not doubt them at all.
But, For some reason - I did not like this question. Reason: The argument expects us to think that soil disturbances might have occurred when dandelions were removed. This is okay, but there could be plenty of other possibilities that could have occurred and be linked to the question as well.

Dear rachitshah,
I'm happy to respond.

I would say that many official CR questions are of the form that if, say, (B) is the OA, then (B) absolutely must play the role asked by the prompt question (strengthener, weakener, etc.), but in other official question, of all five answers, the OA (B) would be the only one that could play this role. Those latter questions are typically much harder questions, and those OAs are exceptionally easy to pass over. I would say this official question is of this latter sort.

Does this make sense?
Mike
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08 Jun 2016, 04:07
mikemcgarry wrote:
amatya wrote:
In Colorado subalpine meadows, nonnative dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.
Which of the following, if true, most seriously undermines the researchers’ reasoning?

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.
(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.
(D) Seed germination is a more reliable measure of a species’ fitness than seed production.
(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

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Dear amatya,
I'm happy to help. As always, this OG question is a great question!

The scientists concluded that "the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots." We want to weaken this conclusion.

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.
If all the bees were visiting dandelions, then this would not explain why the larkspurs got so pollinated, producing a great quantity of seeds. This is simply inconsistent with the evidence. This is not correct.

(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
This is a strengthener. If this is true, then it would explain why having dandelions in the plot would result in more pollination for the larkspurs. This is a typical GMAT CR trap, having a strengthener for a weakener, or vice versa. This is not correct.

(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.
This is a problems down the road, a reason why in the big picture dandelions might be a problem for larkspars, but it doesn't do anything to address the issue of which plants get pollinated and how many seeds are produced. This is not correct.

(D) Seed germination is a more reliable measure of a species’ fitness than seed production.
Even if this is true, it is not relevant, because in terms of the experiment, only seed production was measured. There was no measurement of seed germination: at most, it was merely inferred from seed production. The experiment left no means to distinguish between these two, so the distinction in this context is experimentally meaningless. This is incorrect.

(E) Soil disturbances can result in fewer blooms, and hence lower seed production.
This may appear irrelevant at first glance, but think about it. The control plot (with dandelions) produced more seeds than the experimental, dandelion-free plot. How was that latter plot prepared? The prompt says: "all dandelions were removed from eight plots." In other words, all the dandelions were ripped out, disturbing the soil. According to this answer choice, this soil disturbance would have inhibited seed production in the control group. This provides an alternative explanation to the experimental results: according to this view, the fact that the control group had more seeds than the experimental group has nothing to do with the presence or absence of dandelions, but with the presence or absence of soil disturbance. Providing a cogent alternative explanation shatters the reliability of the argument. This is a weakener.

(E) has to be the OA. This is a brilliant question, because at first glance, it may appear that (E) is entirely out-of-scope and irrelevant. You have to think about the details of the prompt to recognize why it is so relevant.

Does all this make sense? Here's a blog with more thoughts about weakening arguments:
https://magoosh.com/gmat/2012/how-to-we ... reasoning/

Mike

I thought that the reasoning was that seed production was facilitated by the presence of dandelions attracting more pollinators. Answer choice B implies that attracting pollinators is not the mechanism through which see production is facilitated. So answer B weakens the argument, doesn't it?

Last edited by HiLine on 08 Jun 2016, 07:40, edited 1 time in total.

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08 Jun 2016, 04:08
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EMPOWERgmatMax wrote:
In Colorado subalpine meadows, nonnative dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Which of the following, if true, most seriously undermines the researchers' reasoning?

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.

(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.

(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.

(D) Seed germination is a more reliable measure of a species' fitness than seed production.

(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

Type: Weaken
Boil It Down: Dandelions removed, larkspur down -> Dandelions boost pollination of native
Missing Information: Were there other factors?
Goal: Find the option that shows that the difference in pollination between the two groups in the study is not about the presence of dandelions.

A) This option doesn't weaken for two reasons: 1) A preference doesn't necessarily mean that bumblebees still wouldn't visit both plants 2) The option flat out doesn't weaken the argument. In fact, if anything it appears to have the flavor of a strengthener since a preference toward dandelions would seem to support the findings of the study that dandelions are luring bumblebees to native plants.

B) This option would also appear to strengthen the argument that the presence of dandelions boosts pollination of native plants since this option would suggest that pollination is enhanced in mixed plots (those that include dandelions).

C) Overcrowding could very well occur, but that wouldn't weaken the claim that the presence of dandelions still boosts native plant production. Gone.

D) This option centers on the measurement of species fitness, but species fitness is a completely different topic. This option is completely Out of Focus.

E) Yes! Here we have an option that directly offers an alternative explanation. The difference in pollination in the study wasn't the presence of dandelions (or the lack of them) but rather the fact that the removal of the dandelions in the study disrupted blooms, and thus pollination. This option exposes the dark truth that this study is miserably flawed.

But answer B implies that the result is not achieved by attracting pollinators, so it weakens the argument, doesn't it?

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08 Jun 2016, 04:39
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HiLine I recommend Strategy Guide for CR. Believe me you life will not remain the same after assimilating that.
Your question above suggests that you will benefit greatly from fundamental books as Strategy Guide.
Get any edition.

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08 Jun 2016, 07:04
HiLine wrote:
EMPOWERgmatMax wrote:
In Colorado subalpine meadows, nonnative dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Which of the following, if true, most seriously undermines the researchers' reasoning?

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.

(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.

(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.

(D) Seed germination is a more reliable measure of a species' fitness than seed production.

(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

Type: Weaken
Boil It Down: Dandelions removed, larkspur down -> Dandelions boost pollination of native
Missing Information: Were there other factors?
Goal: Find the option that shows that the difference in pollination between the two groups in the study is not about the presence of dandelions.

A) This option doesn't weaken for two reasons: 1) A preference doesn't necessarily mean that bumblebees still wouldn't visit both plants 2) The option flat out doesn't weaken the argument. In fact, if anything it appears to have the flavor of a strengthener since a preference toward dandelions would seem to support the findings of the study that dandelions are luring bumblebees to native plants.

B) This option would also appear to strengthen the argument that the presence of dandelions boosts pollination of native plants since this option would suggest that pollination is enhanced in mixed plots (those that include dandelions).

C) Overcrowding could very well occur, but that wouldn't weaken the claim that the presence of dandelions still boosts native plant production. Gone.

D) This option centers on the measurement of species fitness, but species fitness is a completely different topic. This option is completely Out of Focus.

E) Yes! Here we have an option that directly offers an alternative explanation. The difference in pollination in the study wasn't the presence of dandelions (or the lack of them) but rather the fact that the removal of the dandelions in the study disrupted blooms, and thus pollination. This option exposes the dark truth that this study is miserably flawed.

But answer B implies that the result is not achieved by attracting pollinators, so it weakens the argument, doesn't it?

Hi HiLine,

The reasoning behind your question is not entirely clear. Please elaborate.
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08 Jun 2016, 07:37
EMPOWERgmatMax wrote:
HiLine wrote:
EMPOWERgmatMax wrote:
In Colorado subalpine meadows, nonnative dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Which of the following, if true, most seriously undermines the researchers' reasoning?

(A) Bumblebees preferentially visit dandelions over larkspurs in mixed plots.

(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.

(C) If left unchecked, nonnative species like dandelions quickly crowd out native species.

(D) Seed germination is a more reliable measure of a species' fitness than seed production.

(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

Type: Weaken
Boil It Down: Dandelions removed, larkspur down -> Dandelions boost pollination of native
Missing Information: Were there other factors?
Goal: Find the option that shows that the difference in pollination between the two groups in the study is not about the presence of dandelions.

A) This option doesn't weaken for two reasons: 1) A preference doesn't necessarily mean that bumblebees still wouldn't visit both plants 2) The option flat out doesn't weaken the argument. In fact, if anything it appears to have the flavor of a strengthener since a preference toward dandelions would seem to support the findings of the study that dandelions are luring bumblebees to native plants.

B) This option would also appear to strengthen the argument that the presence of dandelions boosts pollination of native plants since this option would suggest that pollination is enhanced in mixed plots (those that include dandelions).

C) Overcrowding could very well occur, but that wouldn't weaken the claim that the presence of dandelions still boosts native plant production. Gone.

D) This option centers on the measurement of species fitness, but species fitness is a completely different topic. This option is completely Out of Focus.

E) Yes! Here we have an option that directly offers an alternative explanation. The difference in pollination in the study wasn't the presence of dandelions (or the lack of them) but rather the fact that the removal of the dandelions in the study disrupted blooms, and thus pollination. This option exposes the dark truth that this study is miserably flawed.

But answer B implies that the result is not achieved by attracting pollinators, so it weakens the argument, doesn't it?

Hi HiLine,

The reasoning behind your question is not entirely clear. Please elaborate.

This is how I read the whole thing:

The conclusion says that the presence of dandelions facilitates seed production by attracting pollinators. Answer B implies that dandelions facilitate seed production by allowing pollinators to transfer pollen from one species to another, thus weakening the argument.

Let me know if you need further elaboration.

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08 Jun 2016, 10:43
HiLine wrote:
I thought that the reasoning was that seed production was facilitated by the presence of dandelions attracting more pollinators. Answer choice B implies that attracting pollinators is not the mechanism through which see production is facilitated. So answer B weakens the argument, doesn't it?

Dear HiLine,
I'm happy to respond. As a huge Beethoven fan, I very much enjoy the icon you have chosen for your representation.

Here's the text of (B).
(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
This choice is not suggesting a mechanism for pollen transfer different from the pollinators. The pollinators are still involved. If pollinators are attracted to the mixed plot, as the prompt suggests, then choice clarifies that the pollinators, who have already been attracted, can cross-fertilize the two plants. It is 100% consistent with the original argument and hence strengthens it.

Does this make sense?
Mike
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08 Jun 2016, 10:59
In Colorado subalpine meadows, nonnative dandelions co-occur with a native flower, the larkspur. Bumblebees visit both species, creating the potential for interactions between the two species with respect to pollination. In a recent study, researchers selected 16 plots containing both species; all dandelions were removed from eight plots; the remaining eight control plots were left undisturbed. The control plots yielded significantly more larkspur seeds than the dandelion-free plots, leading the researchers to conclude that the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Which of the following, if true, most seriously undermines the researchers' reasoning?

(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.

(E) Soil disturbances can result in fewer blooms, and hence lower seed production.

Type: Weaken
Boil It Down: Dandelions removed, larkspur down -> Dandelions boost pollination of native
Missing Information: Were there other factors?
Goal: Find the option that shows that the difference in pollination between the two groups in the study is not about the presence of dandelions.

B) This option would also appear to strengthen the argument that the presence of dandelions boosts pollination of native plants since this option would suggest that pollination is enhanced in mixed plots (those that include dandelions).

E) Yes! Here we have an option that directly offers an alternative explanation. The difference in pollination in the study wasn't the presence of dandelions (or the lack of them) but rather the fact that the removal of the dandelions in the study disrupted blooms, and thus pollination. This option exposes the dark truth that this study is miserably flawed.

HiLine wrote:
But answer B implies that the result is not achieved by attracting pollinators, so it weakens the argument, doesn't it?
Hi HiLine,

The reasoning behind your question is not entirely clear. Please elaborate.

This is how I read the whole thing:

The conclusion says that the presence of dandelions facilitates seed production by attracting pollinators. Answer B implies that dandelions facilitate seed production by allowing pollinators to transfer pollen from one species to another, thus weakening the argument.

Let me know if you need further elaboration.

Hi HiLine,

To confirm your reasoning: you're saying that B provides a counter-theory in that B refers to instances of the SAME pollinators transferring pollen to different plant species to boost pollination, therefore it appears to run counter to the claim that mixed plots increases the NUMBER of pollinators.

Two Critical And Larger GMAT Perspective Issues
I'm glad you asked because your question will enable us to look at some bigger perspective items that will help boost your accuracy.

1) Correct GMAT Weakener Options NEVER, EVER directly contradict the facts. That's actually one of the reasons why we urge such caution when GMAT students feel inclined to use non-official material to try to save money---we've seen inferior question sources outright contradict the prompt. That will never happen on the real thing. So, that said, your read on B requires the interpretation that it contradicts the stated fact that the number of pollinators increased. That interpretation must be ruled out immediately.

2) "CAN" - The GMAT test-writers love to measure the unfounded assumptions test-takers make. How often is "can"? It could be 1 in 1,000,000, and thus statistically irrelevant. For B to be of perceived value, you'd have to make the assumption that "can" implies a relevant frequency. We can't make that kind of assumption here or in any CR question.
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08 Jun 2016, 18:35
mikemcgarry wrote:
HiLine wrote:
I thought that the reasoning was that seed production was facilitated by the presence of dandelions attracting more pollinators. Answer choice B implies that attracting pollinators is not the mechanism through which see production is facilitated. So answer B weakens the argument, doesn't it?

Dear HiLine,
I'm happy to respond. As a huge Beethoven fan, I very much enjoy the icon you have chosen for your representation.

Here's the text of (B).
(B) In mixed plots, pollinators can transfer pollen from one species to another to augment seed production.
This choice is not suggesting a mechanism for pollen transfer different from the pollinators. The pollinators are still involved. If pollinators are attracted to the mixed plot, as the prompt suggests, then choice clarifies that the pollinators, who have already been attracted, can cross-fertilize the two plants. It is 100% consistent with the original argument and hence strengthens it.

Does this make sense?
Mike

Mike, that makes sense. But the increased seed production could be caused merely by the cross-species pollen transfer, which provides no ground for the conclusion that seed production is argumented by dandelions attracting more pollinators (sorry I forgot to include the key word "more" in the previous post! )

Ha great to run into someone that appreciates my avatar! You must be smart for liking Beethoven's music.

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Re: Bumblebees OG 2016 In Colorado subalpine meadow   [#permalink] 08 Jun 2016, 18:35

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