For most species of animals, the number of individuals in the species

Question

For most species of animals, the number of individuals in the species is inversely proportional to the average body size for members of the species: the smaller the body size, the larger the number of individual animals. The tamarin, a small South American monkey, breaks this rule. Of the ten primate species studied in Peru's Manu National Park, for example, the two species of tamarins, saddle-backed and emperor, are the eighth and ninth least abundant, respectively. Only the pygmy marmoset, which is even smaller, is less abundant. The tamarin's scarcity is not easily explained; it cannot be dismissed as a consequence of diet, because tamarins feed on the same mixture of fruit, nectar, and small prey as do several of their more numerous larger counterparts, including the two capuchins known as the squirrel monkey and the night monkey. Although the relative proportions of fruits consumed varies somewhat among species, it is hard to imagine that such subtle differences are crucial to understanding the relative rarity of tamarins.

To emphasize just how anomalously rare tamarins are, we can compare them to the other omnivorous primates in the community. In terms of numbers of individuals per square kilometer, they rank well below the two capuchins, the squirrel monkey and the night monkey. And in terms of biomass, or the total weight of the individuals that occupy a unit area of habitat, each tamarin species is present at only one-twentieth the mass of brown capuchins or one-tenth that of squirrel monkeys. To gain another perspective, consider the spatial requirements of tamarins. Tamarins are rigidly territorial, vigorously expelling any intruders that may stray within the sharply defined boundaries of their domains. Groups invest an appreciable part of their time and energy in patrolling their territorial boundaries, announcing their presence to their neighbors with shrill, sweeping cries. Such concerted territoriality is rather exceptional among primates, though the gibbons and siamangs of Asia show it, as do a few other New World species such as the titi and night monkeys. What is most surprising about tamarin territories is their size. Titi monkeys routinely live within territories of 6 to 8 hectares, and night monkeys seldom defend more than 10 hectares, but tamarin groups routinely occupy areas of 30 to 120 hectares. Contrast this with the 1 to 2 hectares needed by the common North American gray squirrel, a nonterritorial mammal of about the same size. A group of tamarins uses about as much space as a troop of brown capuchins, though the latter weighs 15 times as much. Thus, in addition to being rare, tamarins require an amount of space that seems completely out of proportion to their size.   1 
 RC22661-01.01 
 1. The author indicates that tamarin territories are

A. surprisingly large
B. poorly situated
C. unusually abundant in food resources
D. incapable of supporting large troops of tamarins
E. larger in Peru than in other parts of South America

2 
 RC22661-02.01 
 2. The author mentions the spatial requirements of the gray squirrel in order to

A. explain why they are so common
B. demonstrate the consequences of their nonterritoriality
C. emphasize the unusual territorial requirements of the tamarin
D. provide an example of a major difference between squirrels and monkeys
E. provide an example of an animal with requirements similar to those of the tamarin

3 
 RC22661-03.01 
 3. The author regards the differences between the diets of the tamarins and several larger species as

A. generally explicable in terms of territory size
B. apparently too small to explain the rarity of tamarins
C. wholly predictable on the basis of differences in body size
D. a result of the rigid territoriality of tamarins
E. a significant factor in determining behavioral differences

4 
 RC22661-04.01 
 4. Which of the following would most probably be regarded by the author as anomalous?

A. A large primate species that eats mostly plants
B. A species of small mammals that is fiercely territorial
C. Two species of small primates that share the same territories
D. A species of small birds that is more abundant than many species of larger birds
E. A species of small rodents that requires more living space per individual than most species of larger rodents

5 
 RC22661-05.01 
 5. The author most probably regards the tamarins studied in Manu National Park as

A. an endangered species
B. typical tamarins
C. unusually docile
D. the most unusual primates anywhere
E. too small a sample to be significant

6 
 RC22661-06.01 
 6. Which of the following is NOT mentioned in the passage as a species whose groups display territoriality?

A. Gibbons
B. Siamangs
C. Titi monkeys
D. Squirrel monkeys
E. Night monkeys

7 
 RC22661-07.01 
 7. The primary concern of the passage is to

A. recommend a policy
B. evaluate a theory
C. describe an unusual condition
D. explain the development of a hypothesis
E. support one of several competing hypotheses

Businessconquerer · Accepted Answer

Everything you see in RC is entirely related to the passage unless the question asks you to draw an analogy, ask you to interpret a possible future scenario or requires you to apply the scenario in other condition

NOW this passage took me 3 mins 20 secs to read, however, it took me a little less than a minute on average to solve the questions.

THIS IS AN EASY RC

Let's begin analysing

THE PASSAGE ORGANISATION
Paragraph 1 (A special species)
A general trend is presented
An exception to it is introduced
Exception is supported by illustrations
A possible explanation is described and rejected with reason

Paragraph 2 (What makes it special)
Rarity based on another factor
Compared with other populations
Successfully showing the rarity

I named the two paragraphs because this is a technique I developed while preparing for the IELTS, it actually helps you answer the primary purpose questions.
Let us begin analysing now

Before we move to the questions, note that the method I'll follow is "tournament method" where Round 1 will be "MENTIONED(men)" v "NOT MENTIONED(nmen)" and Round 2 will be  comparing the details , most of the easy questions get answered in round 1 itself

The author indicates that tamarin territories are

A. surprisingly large (Men)
B. poorly situated (nmen)
C. unusually abundant in food resources (nmen)
D. incapable of supporting large troops of tamarins (nmen)
E. larger in Peru than in other parts of South America (nmen)

Note that one can infer option D and E but D is a false statement(opposite) and E shows a comparison that has not been drawn.

The author mentions the spatial requirements of the gray squirrel in order to

A. explain why they are so common  nmen 
B. demonstrate the consequences of their nonterritoriality  nmen 
C. emphasize the unusual territorial requirements of the tamarin  men 
D. provide an example of a major difference between squirrels and monkeys nmen
E. provide an example of an animal with requirements similar to those of the tamarin  men

Both C and E need careful comparison
Both statements are true
But you need to know what is actually going on in the place where the detail is mentioned. If you remember well and good but if you do not, re read
 
What is most surprising about tamarin territories is their size. Titi monkeys routinely live within territories of 6 to 8 hectares, and night monkeys seldom defend more than 10 hectares, but tamarin groups routinely occupy areas of 30 to 120 hectares. Contrast this with the 1 to 2 hectares needed by the common North American gray squirrel, a nonterritorial mammal of about the same size. A group of tamarins uses about as much space as a troop of brown capuchins, though the latter weighs 15 times as much. Thus, in addition to being rare, tamarins require an amount of space that seems completely out of proportion to their size.

While they are showing territorial requirements of this Squirrel monkeys, in the bigger picture the question is asking "WHY???"
C answers that why, given the first statement of the part that I just mentioned

The author regards  the differences  between the diets of the tamarins and several larger species as

A. generally explicable in terms of territory size  nmen 
B. apparently too small to explain the rarity of tamarins  men 
C. wholly predictable on the basis of differences in body size  nmen 
D. a result of the rigid territoriality of tamarins  nmen 
E. a significant factor in determining behavioral differences  nmen

WHILE E might topple some of you
But look Closely, B is the exact opposite of E

as Seen from the organisation of passage, we are neglecting that food possibility.

Which of the following would most probably be regarded by the author as anomalous?

A. A large primate species that eats mostly plants  nmen 
B. A species of small mammals that is fiercely territorial  men 
C. Two species of small primates that share the same territories  nmen 
D. A species of small birds that is more abundant than many species of larger birds  nmen 
E. A species of small rodents that requires more living space per individual than most species of larger rodents  men

This is like a rip off of an analogy question
It is true that the option B is mentioned as is option E, however, Being fiercely territorial is just a characteristic of the monkey that the author is okay with, and seeing that such monkeys live in a larger space than is required gives us E as an answer from analogy.

The author most probably regards the tamarins studied in Manu National Park as

A. an endangered species
B. typical tamarins
C. unusually docile
D. the most unusual primates anywhere
E. too small a sample to be significant

This one can be solved easily with the mentioned v not mentioned technique but still I can explain in depth as to why B or better, use elimination
A is clearly not mentioned or inferrable

B looks good; you don't agree?? Well, see it this way, they described tamarins as a special species bcoz of some reason, "ALL TAMARINS" and then they describe 2 from that park as an evidence, therefore, as stupid as it may sound from an AWA perspective, they just said 2 tamarins are representative of the tamarins as a whole, therefore "typical tamarins" typical in the sense that they are special

C I don't even know why this option is even there, clearly the worst of 5

D Tempting let's keep it for round 2

E That is what we would think but as mentioned in statement of B, the author is saying 2=ALL, can't challenge THE PREMISE in RC & CR

ROUND 2
 E v B
There is no comparison within primates rather just justifying 2 = ALL
which leaves us with B
E also uses extreme language by using not the word "most" but the word "anywhere"
I hope this is helpful  SajjadAhmad   JS1290   prototypevenom   robu1   neha283 
 bb  I hope I'm helping everyone

Which of the following is NOT mentioned in the passage as a species whose groups display territoriality?

A. Gibbons
B. Siamangs
C. Titi monkeys
D. Squirrel monkeys
E. Night monkeys

TRICKY!!! BUT IF YOU READ THIS, IT IS PRETTY STRAIGHT FORWARD
Such concerted territoriality is rather exceptional among primates, though the gibbons and siamangs of Asia show it, as do a few other New World species such as the titi and night monkeys

The primary concern of the passage is to

A. recommend a policy
B. evaluate a theory
C. describe an unusual condition
D. explain the development of a hypothesis
E. support one of several competing hypotheses

Read the organisation, tone= descriptive, no development shown, no support to  several theories 
Pretty direct

Priyanka1293 · Answer

I think Typical tamarins is right because the author studies one group of tamarins, and then applies his findings to the entire species so he must believe that these tamarins are typical tamarins, meaning all the other tamarins are just like these. I chose A "endangered specie", but then realized that the author only mentions rare, and just because it's rare concluding that it is endangered is taking it a little too far.

Skyline393 · Answer

The author indicates that tamarin territories are

A. surprisingly large =>  "in addition to being rare, tamarins require an amount of space that seems completely out of proportion to their size." 
B. poorly situated
C. unusually abundant in food resources
D. incapable of supporting large troops of tamarins
E. larger in Peru than in other parts of South America

The author mentions the spatial requirements of the gray squirrel in order to

A. explain why they are so common
B. demonstrate the consequences of their nonterritoriality
C. emphasize the unusual territorial requirements of the tamarin =>  To emphasize just how anomalously rare tamarins are, we can compare them to the other omnivorous primates in the community. In terms of numbers of individuals per square kilometer, they rank well below the two capuchins, the squirrel monkey and the night monkey. And in terms of biomass, or the total weight of the individuals that occupy a unit area of habitat, each tamarin species is present at only one-twentieth the mass of brown capuchins or one-tenth that of squirrel monkeys. To gain another perspective, consider the spatial requirements of tamarins. 
D. provide an example of a major difference between squirrels and monkeys
E. provide an example of an animal with requirements similar to those of the tamarin

The author regards the differences between the diets of the tamarins and several larger species as

A. generally explicable in terms of territory size
B. apparently too small to explain the rarity of tamarins =>  Although the relative proportions of fruits consumed varies somewhat among species, it is hard to imagine that such subtle differences are crucial to understanding the relative rarity of tamarins. 
C. wholly predictable on the basis of differences in body size
D. a result of the rigid territoriality of tamarins
E. a significant factor in determining behavioral differences

Which of the following would most probably be regarded by the author as anomalous?

A. A large primate species that eats mostly plants
B. A species of small mammals that is fiercely territorial
C. Two species of small primates that share the same territories
D. A species of small birds that is more abundant than many species of larger birds
E. A species of small rodents that requires more living space per individual than most species of larger rodents =>  in addition to being rare, tamarins require an amount of space that seems completely out of proportion to their size.

The author most probably regards the tamarins studied in Manu National Park as

A. an endangered species
B. typical tamarins =>  Of the ten primate species studied in Peru's Manu National Park, for example, the two species of tamarins, saddle-backed and emperor, are the eighth and ninth least abundant, respectively. 
C. unusually docile
D. the most unusual primates anywhere
E. too small a sample to be significant

Which of the following is NOT mentioned in the passage as a species whose groups display territoriality?

A. Gibbons
B. Siamangs
C. Titi monkeys
 D. Squirrel monkeys 
E. Night monkeys
Such concerted territoriality is rather exceptional among primates, though   the gibbons and siamangs   of Asia show it, as do a few other New World species such as the titi and night monkeys. What is most surprising about tamarin territories is their size.   Titi monkeys   routinely live within territories of 6 to 8 hectares, and   night monkeys   seldom defend more than 10 hectares, but tamarin groups routinely occupy areas of 30 to 120 hectares. Contrast this with the 1 to 2 hectares needed by the common North American gray squirrel, a nonterritorial mammal of about the same size.

The primary concern of the passage is to

A. recommend a policy
B. evaluate a theory
C. describe an unusual condition => Describe   "how anomalously rare tamarins are.."  
D. explain the development of a hypothesis
E. support one of several competing hypotheses

janadipesh · Answer

RC22661-05.01
The author most probably regards the tamarins studied in Manu National Park as

A. an endangered species
 B. typical tamarins  ... 1) The tamarin, a small South American monkey,  breaks this rule  2) The tamarin's scarcity is not easily explained 
C. unusually docile
D. the most unusual primates anywhere
 E. too small a sample to be significant ... Ofcourse the sample group is small (Of the  ten primate species studied  in Peru's Manu National Park) but Author never mentioned it 'too small to be significant'

Vinit800HBS · Answer

8mins 30 seconds
All correct.

Classic passage that teaches you not to get too engrossed in minor details. You can always refer back to the passage for deeper understanding.

Tag me if you need explanation to any question.

Posted from my mobile device

neha283 · Answer

Hey, 
Could you elaborate on the "typical" nature of tamarins in Question 5. I did not understand why this answer is correct and what is the author trying to tell by saying typical tamarins.
TIA!

100mitra · Answer

RC#6 Long Passage - {15 mins 6/7 correct}

Pharaphasing  
  Para 1:   Introduction to Tamarin small American monkey (Type: Saddle backed & Emperor) - breaking rule of territory utilization w.r.t their population, their scarcity cannot be easily explained, despite abundant food availability as others

Para 2:   Tamarin comparison with other species and their behaviour of marking own territory 
Comparison (per sq. kms) & (biomass) with two capuchins (squirrel monkey and night monkey)
Comparison (territory concert) with the gibbons, siamangs of Asia few and the titi and night monkeys.
Comparison (size) holding territory utilization with Titi and night monkeys

Conclusion   Being rare, tamarins require an amount of space that seems completely out of proportion to their size.

1. The author indicates that tamarin territories are  
A. surprisingly large 
  Correct: Mentioned in last line of passage “in addition to being rare, tamarins require an amount of space that seems completely out of proportion to their size”  
B. poorly situated 
  Wrong:    Mentioned in para 2 comparison with other omnivorous primates, they hold large space (per sq.km), biomass area, w.r.t size large proportion of territory, with abundant food available.
C. unusually abundant in food resources 
  Wrong:    Mentioned in para 1, “tamarins feed on the same mixture of fruit, nectar, and small prey as do several of their more numerous larger counterparts”
D. incapable of supporting large troops of tamarins
  Wrong:    Mentioned in para 2 “Groups invest an appreciable part of their time and energy in patrolling their territorial boundaries, announcing their presence to their neighbours with shrill, sweeping cries.”
E. larger in Peru than in other parts of South America
  Wrong:    this information is not mentioned in passage

2. The author mentions the spatial requirements of the grey squirrel in order to  
  Explanation:   
while comparison with Tamarian and grey squirrel in terms of biomass, or the total weight of the individuals that occupy a unit area of habitat, each tamarin species is present at only one-twentieth the mass of brown capuchins or one-tenth that of squirrel monkeys
So, we need to find solution where territorial (spatial) requirement comparison has in below option.

A. explain why they are so common  – No, this is not about territory comparison 
B. demonstrate the consequences of their non territoriality  – No both have territory, we need to highlight which one has bigger territory 
C. emphasize the unusual territorial requirements of the tamarin   – Yes ! as per explanation mentioned above.  
D. provide an example of a major difference between squirrels and monkeys  – No, this is not about territory comparison  
E. provide an example of an animal with requirements similar to those of the tamarin
 No, can be a trap! If we ignore word “example”, here comparison is between Tamarian and grey squirrel, grey squirrel is not the example

3. The author regards the differences between the diets of the tamarins and several larger species as  
  Explanation:   Why the question asks about difference between diet? 
as mentioned in passage para 1,
“The tamarin's scarcity is not easily explained; it cannot be dismissed as a consequence of diet, because tamarins feed on the same mixture of fruit, nectar, and small prey as do several of their more numerous larger counterparts” – Food is abundant, territory is large and still population size of Tamarian size is rare, why?

A. generally explicable in terms of territory size
  Wrong:   this is not to understand only territory size
B. apparently too small to explain the rarity of tamarins
  Correct:   as explanation mentioned above 
C. wholly predictable on the basis of differences in body size
  Wrong:   No Tamarian have good diet intake, good space to live, despite of smaller in size, only their population was rare. 
D. a result of the rigid territoriality of tamarins
  Wrong:   Tamarian have abundant diet, and territory to live 
E. a significant factor in determining behavioral differences
  Wrong:   this is not about behavioural difference between the species

4. Which of the following would most probably be regarded by the author as anomalous?  
  We need anomalous answer, which is deviating from what is standard, normal, or expected  
A. A large primate species that eats mostly plants
  Wrong:   Could be true. Example Orangutans and gorillas
B. A species of small mammals that is fiercely territorial
  Wrong:   Example itself is rare “Tamarian”
C. Two species of small primates that share the same territories
  Wrong:   Could be true
D. A species of small birds that is more abundant than many species of larger birds
  Wrong:   Could be true – passage last line “the smaller the body size, the larger the number of individual animals”
E. A species of small rodents that requires more living space per individual than most species of larger rodents
  Correct: Interesting! small rodents vs large rodents - as mentioned in passage para 1 line,” For most species of animals, the number of individuals in the species is inversely proportional to the average body size for members of the species: the smaller the body size, the larger the number of individual animals”

5. The author most probably regards the tamarins studied in Manu National Park as  
A. an endangered species  – No information mentioned in passage, it only says tamarins are rare  
B. typical tamarins   – Correct, this is the passage deals about   
C. unusually docile  – No information mentioned in passage, 
D. the most unusual primates anywhere – No information mentioned in passage, 
E. too small a sample to be significant  – No information mentioned in passage,

6. Which of the following is NOT mentioned in the passage as a species whose groups display territoriality?  
  Explanation:   as mentioned in the passage “concerted territoriality is rather exceptional among primates, though the gibbons and siamangs of Asia show it, as do a few other New World species such as the titi and night monkeys”
 Squirrel monkeys  are compared only unit area of habitat & individuals per sq.km 
A. Gibbons - yes
B. Siamangs - yes
C. Titi monkeys - yes
D. Squirrel monkeys  - No 
E. Night monkeys – yes

7. The primary concern of the passage is to  
A. recommend a policy  – No, there is no policy involved in this passage to recommend  
B. evaluate a theory  – No, it’s a observation study based on condition of Tamarian  
C. describe an unusual condition   – Yes, correct “rare species Tamarian”   
D. explain the development of a hypothesis  – No, supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.  
E. support one of several competing hypotheses  – No, supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

Dinesh654 · Answer

Hello experts!

Need help in question 5.
I chose D, even though "The most unusal" sonds extreme.
but B looks out of the eqaution!

Abhishekgmat87 · Answer

Consider the statement from the passage - 
 The tamarin, a small South American monkey, breaks this rule. Of the ten primate species studied in Peru's Manu National Park, for example, the two species of tamarins, saddle-backed and emperor, are the eighth and ninth least abundant, respectively. Only the pygmy marmoset, which is even smaller, is less abundant. 
 
Now think what's the rule -  For most species of animals, the number of individuals in the species is inversely proportional to the average body size for members of the species: the smaller the body size, the larger the number of individual animals.

Tamarins are small in size but their population is also small. The author has studied only 10 primates and found the two species of tamarins, saddle-backed and emperor, the eighth and ninth least abundant. It implies that the 2 species studied are typical tamarins as they are small but least abundant. Option B is correct

We can't infer that the the most unusual primates anywhere just on the basis of study of 10 primates. D is ruled out.

Sajjad1994 · Answer

Official Explanation

5. The author most probably regards the tamarins studied in Manu National Park as

Difficulty Level:   750

Explanation

Inference

This question requires you to make an inference from what the author says about the tamarins studied in Manu National Park to a claim about how the author most likely regards these tamarins. The author considers certain information that has been gathered about the two tamarin species studied in the park, and on the basis of that, makes claims about tamarins in general (note that the author elsewhere in the passage simply refers to  “tamarins”  without qualification, i.e., without referring specifically to  “the tamarins studied in Manu National Park” ). This suggests that the author would regard the tamarins studied in the park as being typical of tamarins generally, at least in the ways discussed.

A.  It is possible that the two tamarin species studied in the park are endangered, but apart from noting the surprisingly small number of individuals belonging to the species, there is no information that would suggest that they are endangered, and the mere fact that the number of members is relatively small compared to the number of members in other species is not sufficient to indicate that they are endangered, as that number could nonetheless be stable or even growing.

B.  Correct.   ‘The author does not specifically mention anything that would indicate that these tamarins are atypical of tamarins in general, and appears to make inferences about tamarins in general on the basis of the two species studied in the park. The author would not be justified in making such inferences if the author believed that the tamarins observed in the park were not in fact typical.

C.  The author does not give any indication that these species are unusually docile, and in fact suggests the opposite by indicating that tamarins vigorously expel any intruders from their territories.

D.  The author does note some ways in which these tamarin species are unusual among primates, but does not indicate that they are “the most unusual primates anywhere.” The author, in fact, indicates that in one of the ways that these species are unusual—their relative scarcity despite their small body size—another primate species, the pygmy marmoset, is even more unusual.

E.  Because the author appears to make some inferences from information about the tamarins studied in the park to claims about tamarins in general, the author does not seem to regard the tamarins studied in the park as too small a sample to be significant.

The correct answer is B.

waytowharton · Answer

KarishmaB

Madam could you please help me with Option A of Q5. It is mentioned in line 1 of Para 2 - "To emphasize just how anomalously rare tamarins are", Doesn't it mean that they are endangered because if something is rare it is endangered.

I have doubt in Q5 as below -

RC22661-05.01
The author most probably regards the tamarins studied in Manu National Park as

A. an endangered species
B. typical tamarins
C. unusually docile
D. the most unusual primates anywhere
E. too small a sample to be significant

KarishmaB · Answer

Endangered means threatened with extinction. We are not given that there is any threat of extinction here. The tamarins are rare means they don't proliferate rapidly (what might be expected from an animal of their small size). But there is no discussion of how low their absolute number is. 
If it is expected that animals of their size would be about 10 per hectare, we might find only 1 per hectare. That doesn't mean that they are about to become extinct. It is the nature of these animals to not reproduce in large numbers (the reason for which researchers are unable to explain).
Plus, we are talking about 'tamarins studied in Manu National Park' i.e. we are talking about some specific tamarins. Just because they are low in number, we cannot say that the species is endangered. 
But the author does conclude things about the entire species based on the behaviour of these tamarins. So she regards them as typical tamarins.

VerbalBot · Answer

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For most species of animals, the number of individuals in the species

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GMAT Reading Comprehension (RC) Questions

For most species of animals, the number of individuals in the species

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