In Colorado subalpine meadows, nonnative dandelions co-occur with a na

Because pollinators CAN'T transfer pollen from one species to another to augment seed production the presence of dandelions facilitates pollination (and hence seed production) in the native species by attracting more pollinators to the mixed plots.

Do these two sentences seem to be working together? I don't think they do. The first seems to contradict the second.

Coming back here again. Any questions on how the first part weakens the second or at least doesn't strengthen the second?

If pollinators cannot transfer pollen from one species to another in mixed plots to augment seed production relative to dandelion-free plots, while seed production is better in mixed plots, the increase in seed production is likely caused by the presence of more pollinators in the mixed plots.

If the pollinators can't transfer pollen how could they possibly facilitate pollination (within the scope of the argument)? We can agree to disagree here. We're getting to the point of me saying the color is blue and you saying it's green:) That's fine. We can agree to disagree.

A.

I think we're actually coming closer to agreement. Please do try your best to disprove my explanation; I'd prefer all GMAT questions had only one correct answer each. Not a fan of exceptions.

You mean if the pollinators cannot transfer pollen from one species to another? Pollinators can transfer pollen among individuals within a species. I read the answer choice as pollinators that can transfer pollen between species are better at facilitating pollination than pollinators that cannot. Did I read it wrong?

Sounds good. Yes - I think that's the issue. We're told that more pollination means more seed production. So it makes sense that if one species can pollinate the other that the pollination would "augment" seed production. That doesn't mean that the inter-plant pollination is better than the intra-plant pollination.

A.

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). 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

hi Mike, after checking all options, I know E is gonna be the correct answer. Nevertheless, I still have no idea of what the passage discusses about. Can you help me with this?

in strengthening/weakening question,an option that is inconsistent with the premise or support a premise can be a possible answer?

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.

(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.

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

It makes complete sense. Infact, during my actual GMAT, sometimes i feel that none of the answer options is either Right or Relevant. I Suppose they are the harder ones like this one in which the OA has been masked

Could you provide more such examples of official or Magoosh questions which are similar to the given one.

Thanks

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