#20 - Some flowering plant species, entirely dependent on

[Dave Killoran]

I chose B. I categorized E as a loser based on believing it was a reverse answer. The last sentence of the stimulus states the opposite in which plants species will no longer be able to reproduce. Please explain why B is wrong and why answer E is correct. Thanks.

Hey W,

We've got three separate explanations of (B) vs (E) up above. Can you perhaps give us some further details on what's not clear here so we can hit the spot that's missing?

In short, with (B) if the sole pollinator is not in danger, that doesn't mean the plant is safe. What if there were other threats like pesticides, human encroachment, etc?

In (E), if some plants get killed off, there's a chance we could then end up killing off certain bee species that might be highly adapted to those plants, because if those plants disappear the bee is out of luck.

Thanks!

[andriana.caban]

Hi!

Please let me know if my reasoning is correct?

1. One species of bees (x) can only feed from one plant species (y)

If we have Bee(x), then it must feed on Plant (y)
If we do not have Plant (y) species --> then we do not have Bee (x) species

2. Some plant species (z) can only be pollinated by one species of bees (a)

I

f we have Plant (z), then Bee (a) must pollinate it
If we do not have Bee (a) species, we do not have Plant (z) species

3. If pesticides destroy a bee species, the plant species cannot reproduce.

Restatement of the contrapositive of 2.

a) "earliest" - Not supported by stimulus

b) If Bee(x) then Plant(y)

c) This could be true since stimulus says "often the...it can feed from a single species of plant". But we need a MUST BE TRUE

d) "most species of flowering plants" this would be correct if it had said "The flowers of some species of flowers could attract only one species of bees and not others" ?

E) If we don't have plant y species we don't have bee x species?

[Adam Tyson]

Perfect! Well done! I don't know that I could add anything more to this analysis.

[Henry Z]

I’m unconvinced by any of these answers.

The stimulus basically says :
Some plant species depend on some pollinating species.
Some pollinating species depend on some plant species.
(I take “often” as “some (more than one)”, or maybe it’s “more than half”? Anyway it doesn’t matter here.)

Two some statements can’t lead to any inference. E is not guaranteed to be true cause it’s totally possible that no pollinating species depends on the specific plant species that went extinct. Not to mention the destruction of habitat doesn’t necessarily mean extinction of the species.

I know it’s not a MUST BE TRUE question, but then B is also possible, despite its reverse logic: What if the plant species in B happens to have no threat, just like no pollinating species depends on the plant species in E? Considering both B and E are typical wrong answers to Inference question, I went with D despite the “most”. It’s only worse when I knew D was wrong because it showed that the testmaker was indeed aware of the diff between “some” and “most”, but they kept that diff in D, ignored that in E.

[katehos]

Hi Henry,

Good job pointing out how certain components of answer choice (E) have alternate possibilities! The important thing to keep in mind about this answer choice, though, is that it says "could cause." By using that phrase, answer choice (E) accounts for such possibilities and is still supported by the stimulus. Since some bees rely only on a single species of plant for food, if a plant species is destroyed when its habitat is destroyed, this could cause a bee species to go extinct from lack of food.

This is the contrapositive of the relationship exhibited in the stimulus between bees/plants: some bee species only pollinate some plant species.

Part of the reason why this question is difficult is because of the very specific phrasing of each answer and how the claims made in certain answer choices, like answer choice (E), are not particularly forceful. But when we look to the contrapositive of the above conditional, then we can support the notion that without certain plants, some bee species might go extinct.

Answer choice (B) uses conditional reasoning, saying that if a sole pollinator isn't in danger of going extinct plant species is unlikely to become extinct.

However, we do not know if there are other reasons a plant species could go extinct. Even if the sole pollinator is not in danger of extinction, perhaps the plant is still likely to go extinct because of other natural events? This answer choice is a mistaken reversal, and so we cannot support this answer with the same level of force that the answer itself uses.

A similar issue is present in answer choice (D), since it utilizes the word "most" species, which we cannot be certain of - good job pointing that out!

Ultimately, it's important to keep in mind the level of certainty required by the question stem and the level of certainty within the answer choice itself! Hope this helps

-Kate

[Henry Z]

Thanks, katehos. It makes much more sense after your explanation!

[ericsilvagomez]

Hi,

I do not see an explanation for the answer choices, so I will explain my thought process: for me, the correct answer came down to B or E. I did not choose B because I interpreted the stimulus as saying that when a pollinating species is feeding from a single plant species, the plant species is in danger of becoming extinct. So, I concluded that the plant species would be in danger of becoming extinct if something happened to that one species. E seemed to most logically follow the stimulus in that the survival of the bee species goes hand in hand with that of the plant species since the bees are pollinators, and the plant species attracts them with its nectar. Please let me know your thoughts about my logic when solving the problem!

[Robert Carroll]

ericsilvagomez,

There is extensive discussion of answer choices (B) and (E) in this thread. Answer choice (B) is a Mistaken Reversal. Answer choice (E) is proven by the facts of the stimulus.

Robert Carroll