Q19 - The great majority of the forests

[noah]

19. (A)
Question type: Inference
To paraphrase the given set of statements: if a threatened forest is going to continue to be a viable home for all the plants and animals that are living there, then a forest ranger _ resource manager _ will have to come and help out on a regular basis. Furthermore, the majority of forests _ the last refuge of many endangered species - are now threatened, and have lost the ability to sustain themselves. From these statements we can infer (A), that if the forest rangers don’t help, many forests will lose at least a species. We can infer this because we know that the forests are unable to support themselves and require help if they are to support all the species that currently live therein.

(B) is unsupported since the argument does not outline which animals are specifically threatened. This is a tempting answer since we know that the forests include these threatened species, but we’re not sure if the threat they face is related to the lack of help from the forest ranger.
(C) is reversed logic. We are told that a fragmented forest will lose some species if the forest is not assisted, not that the loss of the species will lead to the fragmentation of the forest.
(D) is unsupported; indeed it is the opposite of what the statements suggest.
(E) is out of scope. The passage does not discuss what resource managers are doing at the moment.

#officialexplanation

[michaeljanati]

I am still confused about this question--the stimulus specifically states "they include the last refuges for some of the world's most endangered species". So if intervention doesn't take place, and these forests cannot sustain themselves, isn't it then reasonable to infer that many of the endangered species will not survive?

Thanks.

[tianfeng102]

I am still confused about this question--the stimulus specifically states "they include the last refuges for some of the world's most endangered species". So if intervention doesn't take place, and these forests cannot sustain themselves, isn't it then reasonable to infer that many of the endangered species will not survive?

Thanks.

However, there is a gap in your reasoning -- without intervention, definitely some species will not survive. But, maybe none of species lost will be the endangered species. So B is not a Must Be True answer and for inference question, we need to find a Must Be True answer!

P.S. I chose B, too, when taking the PrepTest.

[noah]

I agree with tianfeng102.

With the clock ticking, this is a tough question!

[callmejinny]

I am still confused about this question--the stimulus specifically states "they include the last refuges for some of the world's most endangered species". So if intervention doesn't take place, and these forests cannot sustain themselves, isn't it then reasonable to infer that many of the endangered species will not survive?

Thanks.

However, there is a gap in your reasoning -- without intervention, definitely some species will not survive. But, maybe none of species lost will be the endangered species. So B is not a Must Be True answer and for inference question, we need to find a Must Be True answer!

P.S. I chose B, too, when taking the PrepTest.

Thanks for the explanation. But I'm still confused with this line of logic.

Because if we know that (1) the majority of the forests cannot be self-sustained (which means, unless there is intervention it literally has no chance of living) AND (2) these forests are the "last refuge" for endangered species (which means that there are no other means of sustaining their lives without these forests), can't we infer that without regular/any intervention in these forests (which means these forests would cease to exist), the most endangered species will also lose their "last refuge" and therefore die out?

I mean how else can these endangered species stay alive if no one intervenes?


Thank you!

[mshinners]

Thanks for the explanation. But I'm still confused with this line of logic.

Because if we know that (1) the majority of the forests cannot be self-sustained (which means, unless there is intervention it literally has no chance of living) AND (2) these forests are the "last refuge" for endangered species (which means that there are no other means of sustaining their lives without these forests), can't we infer that without regular/any intervention in these forests (which means these forests would cease to exist), the most endangered species will also lose their "last refuge" and therefore die out?

I mean how else can these endangered species stay alive if no one intervenes?

The stimulus tells us that regular interventions by resource managers are a requirement for the forest to maintain its full complement of plant and animal species. This leaves open the possibility (an in fact implies it's true that), without the intervention, they can still maintain some of their animal species, and it's possible that the endangered ones are the ones that would survive.

[laura.bach]

For (A) I've come round to understand it this way:

World's forests --(most)--> Fragmented / Sickly --> All species survive --> Regular intervention

Negated:

No regular intervention --> Not all species survive in fragmented/sickly forests (AKA most of the World's forests)


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But I also picked (B) and had this same reasoning:

...if we know that (1) the majority of the forests cannot be self-sustained (which means, unless there is intervention it literally has no chance of living) AND (2) these forests are the "last refuge" for endangered species (which means that there are no other means of sustaining their lives without these forests), can't we infer that without regular/any intervention in these forests (which means these forests would cease to exist), the most endangered species will also lose their "last refuge" and therefore die out?

I mean how else can these endangered species stay alive if no one intervenes?

And here's what I think. It's easier to understand if we break the second sentence into two distinct sentences:

"These fragmented forest ecosystems have typically lost the ability to sustain themselves."
"These fragmented forest ecosystems include the last refuges for some of the world's most endangered species."

It is possible there are some fragmented forest ecosystems that are able to sustain themselves long-term, and that's where all of the last refuges/endangered animals are located.

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PS - Although I should note: even if a fragmented forest could sustain itself long term, the last element of fragmented forest ecosystems: "They need regular intervention to maintain a full complement of plant and animal species" means that even if it could sustain itself long-term, without regular intervention, it would still lose some species (though they may not be endangered).

So the scenario that eliminates (B) is:
1. A fragmented forest that can sustain itself long-term and is home to all of the endangered species,
2. Has no intervention, and
3. Is only losing non-endangered species.