Q19

[fyre182]

An explanation of where to find the inference would be very helpful. thanks.

I chose b initially.

[noah]

The phenomenon that this passage offers possible explanations for (and critiques of those explanations) is latitudinal gradiation. What's that mean? It means that there are more species in areas that are closer to the equator than in those areas closer to the poles.

Since a temperate zone grassland is closer to the equator than an arctic one, we can be fairly confident there are more species in the temperate one.

As for the wrong answers:

(A) is contradicted - the tropical area would probably have more species than the temperate one.

(B) is tempting, however it's contradicted: in line 13-15 we learn that some temperate areas have not been as affected by ice ages as others.

(C) is contradicted by line 24.

(E) is tricky, as we learn that isolate population groups do evolve into their own species. However, we also learn - in lines 57-61 - that in some areas the isolated groups are unlikely to survive. We know that when these groups are in arctic areas, they're unlikely to survive - and they're more likely to survive in tropical conditions, but we never learn about the temperate zone, so this answer is unsupported.

I hope that clears it up.

[tzyc]

Hi Noah,

I have a question about the difference between zones...
In line 11 it says "unlike the temperate and arctic zones, have been unaffected by a succession of ice ages" so both temperate and arctic zones are influenced by a succession of ice ages right? Do we need outside knowledge to answer this question? Because based on just this information I'm not sure what their differences are...(or we can infer based on the difference mentioned in L13~).
I read wiki and it seems both temperature and tropical zones are warm areas and not sure about their differences too because both can be closer to equator...so not sure why s/he only mentioned temperate and arctic are not affected by the ice age.

Thank you

[noah]

Hi Noah,

I have a question about the difference between zones...
In line 11 it says "unlike the temperate and arctic zones, have been unaffected by a succession of ice ages" so both temperate and arctic zones are influenced by a succession of ice ages right? Do we need outside knowledge to answer this question? Because based on just this information I'm not sure what their differences are...(or we can infer based on the difference mentioned in L13~).
I read wiki and it seems both temperature and tropical zones are warm areas and not sure about their differences too because both can be closer to equator...so not sure why s/he only mentioned temperate and arctic are not affected by the ice age.

Thank you

No, we don't need outside knowledge here. Lines 13-15 tell us that some temperate zones were disrupted less than others. Thus, perhaps some were not severely affected by a succession.

That clear it up?

[Mab6q]

So B is an answer choice that might be true but is not 100% verifiable.

The issue I had with D was the inclusion of the "larger regional pool". I just felt like that somehow limiting the overall species count of each latitude.

Thank.

[maryadkins]

I agree with you that (B) might be true but might not, though the passage saying that some temperate grassland regions were hit harder than others in line 14 makes me think it'd be weird if it were true.

I'm not sure what you mean by the larger regional pool limiting the overall species count since it is a comparative statement (comparing the temperate grassland to the arctic grassland). If you remain confused can you elaborate?