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Pankaj0901
Request you to please share the explanations, including:
Question 1: How is A wrong? I find it the most apt.
Question 2: I find options B and C convey the same thing. Please clarify why is C wrong?
Question 7: Why not option A? It is clearly stating the relationship between the map sense and olfactory.

Hi Pankaj0901,

Quote:
Question 1: How is A wrong? I find it the most apt.
1. Which one of the following best states the main idea of the passage?

(A) The ability of pigeons to locate and return to their homes from distant points is unlike that of any other species.
(B) It is likely that some map sense accounts for the homing ability of pigeons, but the nature of that sense has not been satisfactorily identified.
(C) The majority of experiments on the homing ability of pigeons have been marked by design flaws.
(D) The mechanisms underlying the homing ability of pigeons can best be identified through a combination of laboratory research and field experimentation.
(E) The homing ability of pigeons is most likely based on a system similar to that used by many short-range species.


Explanation: The author discusses two alternatives about the homing ability of pigeons and how pigeons and some short range species have a "map sense" that accounts for their homing ability that seems promising yet has not been completely identified.
Option A is incorrect as this ability of pigeons is not unique and its similar to that of some short-range species such as honeybees.



Quote:
Question 2: I find options B and C convey the same thing. Please clarify why is C wrong?
2. According to the passage, which one of the following is ordinarily true regarding how homing pigeons “home”?

(B) When they are released they take only a short time to orient themselves before selecting their route home.
Option B can be inferred from the lines: "Homing pigeons can be taken from their lofts and transported hundreds of kilometers in covered cages to unfamiliar sites and yet, when released, be able to choose fairly accurate homeward bearings within a minute and fly home."

(C) Each time they are released at a specific site they take a shorter amount of time to orient themselves before flying home.

The word: "specific site" makes all the difference in making C incorrect. We are asked what is ordinarily true regarding how homing pigeons “home”. Now even if the pigeons are not released at specific sites, yet they can figure their way back and this is what the whole passage talks about.

Quote:
Question 7: Why not option A? It is clearly stating the relationship between the map sense and olfactory.

(A) The map sense of pigeons is most probably related to their olfactory sense.
A is just Papi's hypothesis. The author discusses the problems of the same in the next paragraph and the author challenges it through the lines: "Papi’s experimental results, moreover, admit of simpler, nonolfactory explanations.". Npw option C is one that both Papi and author agree with, that is how homing ability of pigeons is most probably based on a map sense.

Hope This Helps.
Thanks.
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Request to explain question no. 5 as option B and E are sounding same to me
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RahulHGGmat
Request to explain question no. 5 as option B and E are sounding same to me

Explanation

5. The author refers to “the system of many short-range species such as honeybees” (lines 9–11) most probably in order to

Difficulty Level: Medium

Explanation

There could only be two possible purposes for the author to mention, in a parenthesis, the homing system of very different species. Either he wants to provide an analogy that will make the idea of the theory clearer to the reader, or he hopes to lend the theory some credibility by showing that a phenomenon is already present in nature. The latter of the two is what (B) picks up on. Since some short-ranging species use the “inertial system,” it’s at least worth exploring whether the long-ranging pigeon does too.

(A) No “universality” is implied, since the detail in question is tied to one very specific theory.

(C), (D) Discrediting theories, (C), is the purview of Paragraphs 2-4, not Paragraph 1 where the reference in question appears. And while criticizing scientists’ methods, (D), never really occurs at all, those methods are likewise not discussed until the latter half of the passage, and certainly they don’t link up to lines 9-11.

(E) Even if Paragraph 1 were designed to propound a particular theory—which it is not; we noted in our Roadmap that Paragraph 1 simply describes a mystery and two possible solutions—the one to which lines 9-11 relate, the “inertial system,” is not the one the author ends up favoring.

Answer: B

This is not Official explanation rather belongs to Kaplan LSAT
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bm2201 - The way you have explained the answers is amazing- clear and crisp. I understood very easily what I missed. Thank you so much.

bm2201
Pankaj0901
Request you to please share the explanations, including:
Question 1: How is A wrong? I find it the most apt.
Question 2: I find options B and C convey the same thing. Please clarify why is C wrong?
Question 7: Why not option A? It is clearly stating the relationship between the map sense and olfactory.

Hi Pankaj0901,

Quote:
Question 1: How is A wrong? I find it the most apt.
1. Which one of the following best states the main idea of the passage?

(A) The ability of pigeons to locate and return to their homes from distant points is unlike that of any other species.
(B) It is likely that some map sense accounts for the homing ability of pigeons, but the nature of that sense has not been satisfactorily identified.
(C) The majority of experiments on the homing ability of pigeons have been marked by design flaws.
(D) The mechanisms underlying the homing ability of pigeons can best be identified through a combination of laboratory research and field experimentation.
(E) The homing ability of pigeons is most likely based on a system similar to that used by many short-range species.


Explanation: The author discusses two alternatives about the homing ability of pigeons and how pigeons and some short range species have a "map sense" that accounts for their homing ability that seems promising yet has not been completely identified.
Option A is incorrect as this ability of pigeons is not unique and its similar to that of some short-range species such as honeybees.



Quote:
Question 2: I find options B and C convey the same thing. Please clarify why is C wrong?
2. According to the passage, which one of the following is ordinarily true regarding how homing pigeons “home”?

(B) When they are released they take only a short time to orient themselves before selecting their route home.
Option B can be inferred from the lines: "Homing pigeons can be taken from their lofts and transported hundreds of kilometers in covered cages to unfamiliar sites and yet, when released, be able to choose fairly accurate homeward bearings within a minute and fly home."

(C) Each time they are released at a specific site they take a shorter amount of time to orient themselves before flying home.

The word: "specific site" makes all the difference in making C incorrect. We are asked what is ordinarily true regarding how homing pigeons “home”. Now even if the pigeons are not released at specific sites, yet they can figure their way back and this is what the whole passage talks about.

Quote:
Question 7: Why not option A? It is clearly stating the relationship between the map sense and olfactory.

(A) The map sense of pigeons is most probably related to their olfactory sense.
A is just Papi's hypothesis. The author discusses the problems of the same in the next paragraph and the author challenges it through the lines: "Papi’s experimental results, moreover, admit of simpler, nonolfactory explanations.". Npw option C is one that both Papi and author agree with, that is how homing ability of pigeons is most probably based on a map sense.

Hope This Helps.
Thanks.
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Sajjad1994 sir,
3. Which one of the following experiments would best test the “possibility” referred to in line 6?

(A) an experiment in which the handlers who transported, released, and otherwise came into contact with homing pigeons released at an unfamiliar site were unaware of the location of the pigeons’ home

I understand, it's a location based question. Aside from reading the minds of the experimenters (a possibility that has not escaped investigation), there are two basic explanations for the remarkable ability of pigeons to “home”.[/color]
How can I figure out that reading the mind of experimenters is related with the unawareness of the experimenters?
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Sajjad1994 sir,
3. Which one of the following experiments would best test the “possibility” referred to in line 6?

(A) an experiment in which the handlers who transported, released, and otherwise came into contact with homing pigeons released at an unfamiliar site were unaware of the location of the pigeons’ home

I understand, it's a location based question. Aside from reading the minds of the experimenters (a possibility that has not escaped investigation), there are two basic explanations for the remarkable ability of pigeons to “home”.[/color]
How can I figure out that reading the mind of experimenters is related with the unawareness of the experimenters?

Explanation

3. Which one of the following experiments would best test the “possibility” referred to in line 6?

Difficulty Level: 700

Explanation

This question picks up on one brief yet intriguing reference early on. The sense of “Aside from...,” lines 5-7, seems jocular (pigeons who are the subject of homing experiments may somehow be reading the scientists’ minds); and then we hear that this is “a possibility that has not escaped investigation.” Can it be? Is science seriously considering whether pigeons telepathically home in on the minds of their human handlers? That seems to be the case, and as nutty as it might sound, such a hypothesis could best be tested by taking the human element out of the equation.

In other words, one would want to test whether pigeons can find their way back home without the ability (however acquired) to read the minds of the experimenters. And that’s

(A). The pigeons’ continued ability to home in the absence of human handlers knowledgeable about the home location would certainly refute the idea in lines 5-6, while impaired homing ability might support it.

(B)’s suggestion that human affection should be taken out of the equation has no relationship to the gist of lines 5-7. It’s human minds that some scientists suspect pigeons of homing in on, not human hearts. Whether friendly or hostile, the human needs to be unaware of the home location in order to test the hypothesis, and that’s what’s specified in (A).

(C) A vow of silence among handlers would not affect the test results. Pigeons are suspected of reading handlers’ minds, not eavesdropping on their conversations or homing in on their voices.

(D) brings up an unwarranted comparison between teams and individuals. Irrelevant. If a mind is being read, it doesn’t matter whether that mind is solo or accompanied.

(E) Presumably an unfamiliar site already contains “unfamiliar sights and sounds.” And even if it didn’t, adding same wouldn’t affect the peculiar, but apparently somewhat serious, hypothesis that pigeons are mind-readers. It just might add more obstacles to whatever seeing and hearing that pigeons engage in.

Answer: A

Explanation Credit: Kaplan LSAT
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can anyone tell me the explantion for the 7 th question?
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can anyone tell me the explantion for the 7 th question?

Welcome! to GMAT Club

Explanation

7. Given the information in the passage, it is most likely that Papi and the author of the passage would both agree with which one of the following statements regarding the homing ability of pigeons?

Difficulty Level: 700

Explanation

We know from the entire final paragraph that the author takes issue with Papi’s theory about pigeons’ olfactory sense as the key to their homing ability. So when we’re asked, as we are here, to come up with an area of agreement between the author and Papi, we have to find a broader, more fundamental view. We can find it in the idea of “map sense,” the second of the two alternatives mentioned in paragraph 1 and the one that “seems more promising.” And Papi likes it too (lines 36-37). Though Papi and the author differ on the nature of that map sense, they agree that it’s likely the answer to the homing question—making (C) correct.

(A) is their area of disagreement: This is Papi’s theory, about which the author is most skeptical.

(B) The honeybees in this passage serve much the same role as does voir dire in Passage 1: as a basis for creating wrong answers! The author explicitly rejects the “inertial system” theory, the one akin to honeybees’ homing system; and insofar as Papi likes the “map sense” theory he’s probably not fond of the honeybee parallel either.

(D) We’re sure that Papi is proud of his research, but the author spends all of Paragraph 4 taking issue with its conclusions, so the seal of approval (D) plants on Papi’s work seems unjustified by the text.

(E) Opposite, the experiments of Schmidt-Koenig and Phillips are explicitly cited in Paragarph 4 as weakening Papi’s reasoning.

Answer: C
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For Q2,are A and C incorrect because of "each time" ?
also please provide an explanation for why E is incorrect in q4.
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For Q2,are A and C incorrect because of "each time" ?
also please provide an explanation for why E is incorrect in q4.

Explanation

2. According to the passage, which one of the following is ordinarily true regarding how homing pigeons “home”?

Difficulty Level: 650

Explanation

The key phrase is “ordinarily true.” Any reference to the “ordinary truth” about homing must take you to Paragrah 1, and indeed to lines 1-5 in particular since everything from line 5 on has to do with that which is unknown, that which is only speculated about pigeons’ homing ability. As it happens, correct choice (B) comes right out of that first sentence; it’s a simple paraphrase of lines 3-5.

(A) would be admirably precise of the pigeons if it were true, but nothing in the passage suggests that they shuttle back and forth between home and a remote site as predictably as a streetcar. Moreover, the scope of the passage concerns pigeons’ ability to return from unfamiliar sites (line 3), not those they visit multiple times.

(C) implies that practice makes perfect, that pigeons find self-orientation easier with each trip home from a particular site. A plausible notion, but (1) it’s never mentioned, and (2) it violates the passage’s concern with pigeons and unfamiliar sites, as discussed in (A), above. If (C) was tempting, maybe you were drawing an unsupported inference from Papi’s hypothesis in lines 37-40. But if you did, what were you doing poking around in Paragraph 3 during this question?

(D), (E) The former describes pigeons wandering extensively in a seemingly random fashion, while (E) specifies a brief preliminary detour. Au contraire: Lines 3-5 suggest proper homeward orientation in under a minute. (D) and (E) may describe ways in which many people return from vacation, but not pigeons.

Answer: B

4. Information in the passage supports which one of the following statements regarding the “first alternative” (line 16) for explaining the ability of pigeons to “home”?

Difficulty Level: 650-700

Explanation

This question is asking in its shy way for the gist of paragraph 2. We know this because that “first alternative” is wholly and only described there. Immediately at line 16 we learn that this alternative, the “inertial system” under which birds would have their own internal compass, “seems unlikely,” and the rest of the paragrapg spells out why: Any time scientists have tried to test the theory by fouling up the birds’ internal senses, using the ploys described in lines 19-29, the homing has continued just fine. What’s lacking, we learn at paragraph’s end, is a “crucial experiment” that would foul up or remove all of the key senses of an inertial system. Inferably, if the birds’ homing ability were impaired after such an experiment, the inertial system hypothesis would be supported. So (C) is right: No data have supported it yet, but it can’t be dismissed because a key experiment hasn’t yet taken place. (And a good thing, too: How’d you like to be a rotated, doped-up pigeon released in total darkness under a crazy magnetic field?)

(A) is too pessimistic given the “crucial experiment,” as yet unperformed.

(B) Contrary, Paragraph 2 hints at several “theoretical models” under which a displacement tracking system might work: light, magnetism, consciousness, etc. The theoretical foundation seems fine; it’s the lack of empirical data that’s the problem.

(D) No such experiments, recent or otherwise, support the “first alternative,” as far as the passage reports.

(E) There seems little difficulty in designing the right experiment; indeed, the very design is described for us in lines 29-33.

Answer: C
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in ques 6 please expain why option E is wrong.
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in ques 6 please expain why option E is wrong.

Explanation

6. Which one of the following, if true, would most weaken Papi’s theory regarding homing pigeons’ homing ability?

Difficulty Level: 700

Explanation

We should first review Papi’s theory before thinking about how to weaken it, and that’s in Para 3 of course. He believes that pigeons’ “map sense” is their sense of smell, that they follow wind-borne odors to get home. Well, if we can in some way drive a wedge between the pigeons’ homing ability and the odors that they allegedly respond to, then we certainly will have cast doubt on Papi’s theory—and that’s why (D) is the winner. If even birds far from familiar odors can get home, then Papi is on shakier ground in ascribing their “map sense” to an olfactory origin.

(A), (C) Each of these speaks to the pigeons’ extraordinary homing ability, but since each fails to mention odors, they cannot affect Papi’s theory one way or the other.

(B) would, if anything, support Papi’s idea, because it implies that the homing ability is impaired when the sense of smell is likewise.

(E) makes an irrelevant comparison between the sense of smell of different bird species. So what? The characteristics of non-homing birds cannot tell us anything about why pigeons succeed in their efforts to get home.

Answer: D
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In Q2, why C is wrong. From "Homing pigeons can be taken from their lofts and transported hundreds of kilometers in covered cages to unfamiliar sites and yet, when released, be able to choose fairly accurate homeward bearings within a minute and fly home.", we can deduce that they align themselves first and then they fly home. There is nothing about choosing a route, maybe they just fly randomly and choose the path along the way!
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please explain question 3
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please explain question 3

Posted here:

https://gmatclub.com/forum/homing-pigeo ... l#p2726844

Thank you!
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Hi KarishmaB GMATNinja MartyMurray

In question-6, I am have two doubts: not clear why option C is wrong and D is correct?


6. Which one of the following, if true, would most weaken Papi’s theory regarding homing pigeons’ homing ability?
(C) Even pigeons that have been raised in the same loft frequently take different routes home when released in unfamiliar territory.
(D) Even pigeons that have been transported well beyond the range of the odours detectable in their home territories can find their way home.

My reasoning:
Option C is correct because pigeons are raised in the same loft (same home) which means when they are released at an unfamiliar place, they should have a unique route to the home due to the same odour, hence, C weakens my conclusion because pigeons take different routes.

Option D is wrong because the passage didn't mention that there can't be any other way to navigate the route to home when odour are out of detectable range so D doesn't impact my confidence.

Please help me to understand where I went wrong in my reasoning.
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Question 6


agrasan
Hi KarishmaB GMATNinja MartyMurray

In question-6, I am have two doubts: not clear why option C is wrong and D is correct?

6. Which one of the following, if true, would most weaken Papi’s theory regarding homing pigeons’ homing ability?

(C) Even pigeons that have been raised in the same loft frequently take different routes home when released in unfamiliar territory.

(D) Even pigeons that have been transported well beyond the range of the odours detectable in their home territories can find their way home.

My reasoning:

Option C is correct because pigeons are raised in the same loft (same home) which means when they are released at an unfamiliar place, they should have a unique route to the home due to the same odour, hence, C weakens my conclusion because pigeons take different routes.

Option D is wrong because the passage didn't mention that there can't be any other way to navigate the route to home when odour are out of detectable range so D doesn't impact my confidence.

Please help me to understand where I went wrong in my reasoning.
The specific route taken doesn't really matter. For example, it's possible that different birds take slightly different routes based on variances in wind conditions, weather, seasonality, predators, or other factors. As long as the birds find their way home using their sense of smell, Papi's theory works. Variations in route wouldn't necessarily weaken that theory, so (C) is out.

Papi's theory is that the pigeons "only have to sniff the air en route and/or at the site to know the direction of home." That's because the birds "come to associate odors borne on the wind with the direction in which the wind is blowing, and so slowly build up an olfactory map of their surroundings."

If you release the birds "well beyond the range of the odors detectable in their home territories," then the birds will not recognize any of the odors at the release site. Without any recognizable odors, the birds would have no idea which way to go. The fact that the birds are able to find their way home even when there are no recognizable odors weakens Papi's theory.

So (D) is the better answer.
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