The song of the yellow warbler signals to other yellow warblers that a

Question

The song of the yellow warbler signals to other yellow warblers that a particular area has been appropriated by the singer as its own feeding territory. Although the singing deters other yellow warblers from taking over the feeding territory of the singer, other yellow warblers may range for food within a portion of the singer’s territory. However, a warbler sings a special song when it molts (sheds its feathers). Other yellow warblers will not enter the smaller core territory of a yellow warbler singing its molting song. Therefore yellow warblers, which can only fly short distances during molting, have no competition for the food supply within the range of their restricted flying.

The argument makes which one of the following assumptions?

(A) The core areas contain just enough food to sustain one yellow warbler while it molts.

(B) Warblers are the only molting birds that lay claim to core areas of feeding territories by singing.

(C) There are no birds other than yellow warblers that compete with yellow warblers for food.

(D) Warblers often share their feeding areas with other kinds of birds, which often do not eat the same insects or seeds as warblers do.

(E) The core areas of each feeding territory are the same size for each molting warbler.

Bunuel · Accepted Answer

EXPLANATION FROM POWER PREP

Due to the verbose nature of stimulus, it is important to isolate the essential elements that form the structure of the argument:

Premise: Yellow warblers sing special songs when molting.

Premise: The special song deters other yellow warblers from encroaching upon the territory of the molting warbler.

Conclusion: A molting warbler has no competition for food within its territory.

Because this is an assumption question, the answer you select must contain a statement upon which the argument depends, i.e. a statement that is  necessary  for the conclusion to be true. All we know from the premises is that  other warblers  will not enter the territory of the singer: that alone does not preclude  other birds  from competing with the singing warbler for food.

Typically, if you see a major weakness in the argument, look for a Defender assumption answer stating that the particular weakness does not exist. In other words, the author must be assuming that no birds other than yellow warblers will compete with the molting warbler for food in its area. This prephrase reveals answer choice (C) to be correct.

Answer choice (A): Whether the core area contains enough food to sustain the molting warbler is irrelevant to the conclusion, which is about whether the warbler faces any competition for the food supply within that area.

Answer choice (B): Whether or not other molting birds can lay claim to the feeding territory of the singer is irrelevant to determining whether the singer would face competition for food in that area.

Answer choice (C): This is the correct answer choice, as it agrees with our prephrase. If this answer is troubling you, use the Assumption Negation Technique and ask yourself if the following statement would undermine the argument:

There are birds other than yellow warblers that compete with yellow warblers for food.

This clearly shows that the author’s conclusion is flawed and weakens her argument. Therefore, answer choice (C) is an assumption upon which the argument depends.

Answer choice (D): This answer choice may seem attractive, because it supports the idea that yellow warblers would face no competition for food in their feeding area: the other kinds of birds simply do not eat the same kinds of food as warblers do. Although this statement supports the conclusion of the argument, it is not necessary for the conclusion to be true. Even if the other birds ate the same kinds of food as warblers do, that does not prove that warblers would face competition in their feeding area, and therefore does not weaken the conclusion of the argument.

Answer choice (E): The relative size of the core areas of each warbler’s feeding territory has no bearing on whether warblers face competition for food. This answer choice falls outside the scope of the argument and is therefore incorrect.

Bunuel · Answer

EXPLANATION FROM Fox LSAT

This argument’s conclusion is much stronger than it should be. The facts were only about yellow warblers, but the conclusion says there will be “no competition for food” during the molting period. The problem with this is that there could be  tons  of competition besides other yellow warblers. What about other birds? What about rabbits? What about… I don’t know… the Cookie Monster?

We’re asked to identify an assumption of the argument. I think the argument has necessarily assumed that the only competition for yellow warbler food is other yellow warblers. Because if that’s not true, then the argument makes no sense at all.

A) Not what we’re looking for.

B) Not what we’re looking for.

C) Exactly what we’re looking for. This is a necessary assumption of the argument because if it is not true, then there are other birds that compete with yellow warblers for food, and therefore the argument would be complete garbage.

D) This would strengthen the argument, because it says other birds don’t eat the same thing as yellow warblers. But the argument did not assume that there are other birds in the area. So this answer could be untrue without ruining the argument’s logic, which means it is not necessary.

E) This definitely doesn’t have to be true for the argument to make sense.

Our answer is C.

deep14 · Answer

C. Yellow warblers don't intrude a fellow warbler's area when it is molting but we can't be sure that other birds also follow this no intrusion policy. Hence the conclusion that the molting bird will not face any food shortage in its territory is dependent on the behaviour of other birds

aurobindomahanty · Answer

what is the problem with option D?

deep14 · Answer

The problem with D is that it says although warblers share territory with other birds, those other birds  often do not eat the same insects or seeds as warblers do . That word often is weakening the assumption as often doesn't rule the instance in which other birds prey upon warbler's food. D would have been a valid choice if you drop often

Loser94 · Answer

Conclusion : Therefore yellow warblers, which can only fly short distances during molting, have no competition for the food supply within the range of their restricted flying

(A) The core areas contain just enough food to sustain one yellow warbler while it molts. 
Can be a assumption . lets find other option

(B) Warblers are the only molting birds that lay claim to core areas of feeding territories by singing. 
Not an assumption.
 
(C) There are no birds other than yellow warblers that compete with yellow warblers for food. 
Definetly a assumption .

(D) Warblers often share their feeding areas with other kinds of birds, which often do not eat the same insects or seeds as warblers do. 
 Weaken conclusion
(E) The core areas of each feeding territory are the same size for each molting warbler.
 Not applicable

So between A and C we use negation theorem .

SO C is more applicable .

Answer C

RohitSaluja · Answer

From other warblers not entering the smaller core territory of a warbler singing its molting song, the author has concluded since no warbler would be entering the territory of warbler which is molting, molting warbler won't have any competition for the food supply. But what if there are other kinds of birds who might compete for the same food sources, Keeping this in mind author has made this big leap that no one except warbler will compete for the same food sources.

Anush56 · Answer

Please help me understand why B is not the answer

AndrewN · Answer

Hello,  Anush56 . (B) falls into a common trap by incorporating overreaching or extreme language when the passage does not provide information to that end.

Yes, we know from the third sentence of the passage that yellow warblers molt, and we discover that they sing what is called a  molting song , one that wards off other yellow warblers that might otherwise enter the  singer's territory . But does the passage tell us about other types of birds? Not at all. It starts with yellow warblers and ends with yellow warblers. Thus, we have nothing to support the notion that warblers among all molting birds are unique in laying claim to certain areas by singing. (B)  cannot  be a necessary assumption to the argument.

Watch out for words such as  only ,  never , and  always . The notion surrounding these words may sound reasonable, but the adverb may be overstating the case and have no basis in the passage.

I hope that helps clarify the matter. Good luck with your studies.

- Andrew

unraveled · Answer

The song of the yellow warbler signals to other yellow warblers that a particular area has been appropriated by the singer as its own feeding territory. Although the singing deters other yellow warblers from taking over the feeding territory of the singer, other yellow warblers may range for food within a portion of the singer’s territory. However, a warbler sings a special song when it molts (sheds its feathers). Other yellow warblers will not enter the smaller core territory of a yellow warbler singing its molting song. Therefore yellow warblers, which can only fly short distances during molting, have no competition for the food supply within the range of their restricted flying.

The argument makes which one of the following assumptions?

(A) The core areas contain just  enough food to sustain one yellow warbler while it molts . - WRONG. If food is enough for one then conclusion is intact. This is irrelevant.

(B) Warblers are the  only molting birds  that  lay claim to core areas of feeding territories by singing . - WRONG. So what!!! It does not matter if its only one or not.

(C) There are  no birds other than yellow warblers that compete  with yellow warblers  for food . - CORRECT. If there are then YW is in trouble. Competition is there then and conclusion doesn't hold.

(D) Warblers  often share their feeding areas  with other kinds of birds, which  often do not eat the same insects or seeds  as warblers do. - WRONG. There's no point of competition there. So, this one hold no value as in if competition is not there then conclusion still stands intact.

(E) The core areas of each feeding territory are the  same size for each molting warbler . - WRONG. "Size" and "each" both doesn't matter. Irrelevant.

Answer C.

VerbalBot · Answer

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The song of the yellow warbler signals to other yellow warblers that a

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