Q25 - The dwarf masked owl, a

[rustyjkent]

This one has me stumped too. Why is (E) a better answer than (D)?

Thank you

[tamwaiman]

(D) is too extreme, and (E) fills the gap between "home" and "nesting site".

[rustyjkent]

Thank you

But why is (D) too extreme.

I appreciate your help thanks!

[ManhattanPrepLSAT1]

Thanks for posting your question on the forum!

The conclusion of the argument is that unless steps are taken to reestablish the spiny cactus population, the dwarf masked owl will not make its home on the Baja peninsula this winter.

By contrapositive, if the dwarf masked owl will make its home on the Baja peninsula this winter, then we must take steps to reestablish the spiny cactus population.

Answer choice (D) actually has the order reversed. Answer choice (D) says that if the dwarf masked owl will not make its winter home on the Baja peninsula, then that region contains no spiny cacti.

Answer choice (E) on the other hand addresses an assumption of the argument. We know that the spiny cactus is the only suitable nesting site for the dwarf masked owl. We also know that the spiny cactus has been destroyed on the Baja peninsula. The argument concludes from this that the dwarf masked owl will not make its home on the Baja peninsula this winter. The assumption of the argument is that the dwarf masked owl will only make it's home in the winter where it has suitable nesting sites - answer choice (E).

(A) is out of scope. We are not concerned with other birds of prey.
(B) is the negation of an assumption of the argument.
(C) supports the conclusion that the dwarf masked owl will not winter in Baja, but is not required in order for that conclusion to be drawn.
(D) is the reversal of an assumption of the argument.

Does that help clear this one up?

[kopoku.08]

i still dont see how B is the wrong answer. E makes sense as an assumption but (e). Please help

[timmydoeslsat]

The issue with this stimulus is the word exchange of home and nesting sites.

Answer choice B is reversed logic.

Here is the stimulus:

This owl normally makes its winter home in this Peninsula where it nests in SC.

There are no other suitable nesting sites other than SC in this Peninsula for this owl.

So we know that if this owl nests in the Peninsula, then it is nesting in SC.

However, this does not mean that if there is SC, that the owl will be there.

[ManhattanPrepLSAT1]

Absolutely right Timmy, answer choice (B) is reversed logic. I would go even further and say that it's not even reversing the logic of an assumption, but rather simply reversing the logic of the conclusion!

[jionggangtu]

If we negate D, what do we get?

Can we say, the region contains no spiny cacti is not the only condition that the dwarf masked owl will not make its winter home on the Baja peninsula?

If there are other reasons might influence where the dwarf masked owl makes its home, then it destroies the orginal argument.

[ericha3535]

Necessary questions are tricky sometimes because they ask for an answer that is so obvious that you feel like the answer is not the one you are looking for.
I mean...
1) No other suitable nesting sites than cacti
2) cacti are eliminated due to a blight
---
3) So... without cacti, birds won't make nests.

Sounds hecka logical... Of course, the cactus is a must-have-thing to induce those birds to make nests.

Anyway

the reason both B and D are wrong is because

1) They are "sort of" reiterations of the last sentence.
The last sentence can be diagrammed as:

~cacti -> ~nest .

B says: cacti -> nest
D says: ~nest -> cacti
Well if they are saying something that is already present in the stimulus, they are no longer assumptions.

2) B is the inverse (mistaken negation) version of the conclusion while the D is the converse (mixed up the sufficient and necessary) version of the conclusion.
So if you choose any of them, you are committing a fallacy.

[kumsayuya]

I saw the issue here as being a sufficient and necessary one.

Basically, the stimulus tells us that the cactus are necessary for the owl to nest there, but many of the answer choices treat it as if its sufficient for them to nest there.

(A) This one just seemed irrelevant so I got rid of it.
(B) Here, its treating the cacti as sufficient in bringing the owls back, but the cacti are necessary - but NOT sufficient. In other words, there could be cacti there, but still have no owls living there.. but there is no way to have no cacti and owls nesting there.
(C) Irrelevant, just like (A) was.
(D) Just like with (B), its treating the cacti as sufficient for the owls to come back (if you reverse this statement, it comes out as cactus--->make their winter home on the peninsula), and as I mentioned earlier this just isn't the case. Cactus aren't sufficient, they are necessary.
(E) This is what is needed. If suitable nesting sites did not need to be present, then the whole argument falls apart- because its based on the fact that since there is no suitable nesting sites, there is no way the owls will be nesting there.

[mggallag]

Why isn't E a premise booster?

[ohthatpatrick]

It definitely feels a bit lost in the weeds of the Premises, like it might just be a Premise Booster.

But it links Premise language to Conclusion language, as we love to see on Assumption answers.

"Suitable nesting cites" comes from the Premise and "must be present for the owl's winter home" comes from the Conclusion.

The Conclusion is very strongly worded .. even conditional strength!

If we don't have spiny cactus, owl won't winter here.
~SPINY --> ~WINTER HOME
(contrapositive: "a winter home requires spiny cactus")

Okay, well how does the author think there's that strong a connection between 'spiny cactus' and the owl's 'winter home'?

What do we know about either concept?

We know that without spiny cactus, you have no suitable nesting sites.
~SPINY --> ~SUITABLE NESTING

Remember, the Conclusion wants to get all the way from
~SPINY --------------------------> ~WINTER HOME

So what are we missing?




~SUITABLE NESTING --> ~WINTER HOME
"if you have no suitable nesting sites, then this won't be your winter home"

Overall structure of Prem+Assumption -> Conclusion
~SPINY --> ~SUITABLE NESTING -> ~WINTER HOME

That's what (E) is doing, giving us that conditional jump.