Careful observers of wildlife along unspoiled freshwater shorelines in

Question

Careful observers of wildlife along unspoiled freshwater shorelines in New England may encounter the river otter (Lutra canadensis) or its close cousin, the mink (Mustela vison). Like other members of the Mustelidae, or "weasel" family, these animals have elongated bodies with long tails and are efficient hunters. On land, they commonly employ the  2-2 bounding gait  characteristic of Mustelidae, but as the only semi-aquatic members of the family in the northeast, they are also accomplished swimmers. Both sport rich, dark fur insulating them from the wet and cold.

Despite such similarities, however, the otter and mink are readily distinguished by sight. The otter is almost twice as long as the mink and may boast ten times the weight of the smaller animal. The rudder-like tail of the otter is markedly heavy-set, tapering only gradually, while that of the mink is gracile. Other, less obvious, differences exist. For example, the otter subsists largely on fish and occasional small mammals, whereas the mink prefers rodents, especially the aquatic muskrat. Similarly, although both animals give birth in the spring, the mink mates in midwinter; the otter mates in spring immediately following the birth, taking advantage of a curious adaptation: delayed implantation of the fertilized egg until the following year. Such variations reflect the fact that even "cousins" traverse different evolutionary pathways.   1 
 1) The purpose of this passage is to

A) Encourage wildlife watchers to study the river otter and mink more carefully.
B) Compare and contrast two closely related animals.
C) Question whether the river otter and mink really belong in the same biological category.
D) Argue that the river otter and mink are fundamentally different.
E) Compare and contrast the  Mustelidae  to the "weasel" family.

2 
 2) The author mentions the "2-2 bounding gait" ( Highlighted ) most probably in order to

A) Contrast aquatic animals with terrestrial animals.
B) Emphasize the energetic efficiency of  Mustelidae  locomotion.
C) Compare the 2-2 gait to the 1-2-1 loping gait of  Mustelidae .
D) Describe a behavioral pattern common to the otter, the mink, and other members of the weasel family.
E) specify the placement of  Mustelidae  forelegs and hind legs when bounding.

3 
 3) The passage suggests that  Mustela vison

A) is a less important member of the  Mustelidae  than  Lutra canadensis .
B) consumes smaller prey than  Lutra canadensis .
C) may be disturbed by the impact of human activity on the environment.
D) has evolved delayed implantation of fertilized eggs.
E) is the most gracile of the  Mustelidae .

RC Butler 2021  -  Practice Two RC Questions Everyday.   
Passage # 156 Date: 20-Apr-2021
 This question is a part of RC Butler 2021 .  Click here for Details

1) The tone of the overall passage is descriptive, not argumentative.  (B) is correct;  though it doesn't mention the otter or the mink specifically, they are "two closely related animals" according to the passage; thus the choice logically applies. The author mentions wildlife observers in the first line, but there is no sense of active encouragement of these observers towards any particular behavior, as mentioned in (A), merely a description of similarities and differences that exist. (C) is not specifically mentioned. The passage is not argumentative as stated in (D). (E) is only half-right: certainly the passage compares and contrasts, but it doesn't compare the Mustelidae to the "weasels." Those classifications are presented as the same family.

2) The key here is to read around the "2-2 bounding gait" quotation and understand it in context. You're being asked why the author mentions the "2-2 bounding gait" not what this scientific term means. (D) fits this inference correctly.  The "2-2 bounding gait" is mentioned in the context of describing similarities between the otter and mink, plus it is referred to as "characteristic"-typical of the Mustelidae or "weasel" family.
(A) is a distortion: The author describes the otter and mink as traveling on land and in water, but makes no general comparison between animals who are limited to one or the other. (B) is out of scope. (C) makes an irrelevant comparison. The second gait pattern is never mentioned so we cannot infer any comparison between them. (E) While the "2-2 bounding gait" may in fact specify leg placement, the passage does not provide such an interpretation and we cannot be expected to interpret such jargon without explanation in the passage.

3) The key to this inference question is sentence 1: careful observers along unspoiled shorelines may observe the animals. In other words, if the shore lines have been spoiled or the human observers are not careful, then the animals may not be present or will be harder to observe, implying that their normal behavior has been disturbed. In (A), the phrase "less important" is vague in this context. The mink is smaller than the otter, but we have no information about their relative "importance." Just because the mink is smaller does not guarantee that it's prey is smaller. Prey is referred to in paragraph 2, but no reference is made to size of prey. (B) is too vague. Delayed implantation is given as an adaptation of the otter in the context of contrasting its breeding strategies to those of the mink, so presumably the mink has not evolved this strategy. That means (D) is out. And (E) is incorrect because the text does not compare the mink to all other members of the Mustelidae family.  C is thus correct.

Gladiator59 · Accepted Answer

3min 23 secs and all correct. I must confess I might have seen this passage before...
 
1) The purpose of this passage is to

A) Encourage wildlife watchers to study the river otter and mink more carefully.  Nah, not even mentioned 
B) Compare and contrast two closely related animals.  Yes, its all in the last sentence of the passage - cousins take different evolutionary paths 
C) Question whether the river otter and mink really belong in the same biological category.  Nope, the author does not questions this - it is a fact 
D) Argue that the river otter and mink are fundamentally different.  No they are not, they have just evolved differently 
E) Compare and contrast the Mustelidae to the "weasel" family.  TRAP - this is not correct as the two terms are interchangeable

2) The author mentions the "2-2 bounding gait" most probably in order to

A) Contrast aquatic animals with terrestrial animals.  Too general 
B) Emphasize the energetic efficiency of Mustelidae locomotion.  BS option 
C) Compare the 2-2 gait to the 1-2-1 loping gait of Mustelidae.  Not even mentioned - the 1-2-1 part 
D) Describe a behavioral pattern common to the otter, the mink, and other members of the weasel family.  Correct - the author wishes to show the similarity between otter mink and other weasels on land and further show how the former two have evolved to aquatic conditions 
E) specify the placement of Mustelidae forelegs and hind legs when bounding   Unrelated

3) The passage suggests that Mustela vison     INFERENCE TYPE - hence we must be able to show this to be 100% true and mentioned explicitely in the passage

A) is a less important member of the Mustelidae than Lutra canadensis.  Wild inference - no mention in the passage 
B) consumes smaller prey than Lutra canadensis.   TRAP  - just because the size is smaller we cannot assume that the prey consumed will be smaller - even if this could likely be the case 
C) may be disturbed by the impact of human activity on the environment.  BINGO - mentioned in the first line of the passage 
D) has evolved delayed implantation of fertilized eggs.  DETAIL question but inverted 
E) is the most gracile of the Mustelidae.  Again BS option

BEst,
Gladi

Enbee11 · Answer

B, D, B 
Reasons :
Question 1: The Passage arranged in such a way that Para 1 describes the two closely related sea animal, para 2 describes the common difference b/w the two i.e otter & Mink. Comaparison & contrast for two same family member animals.
Question 2: The "they" in line "On land, they commonly employ the 2-2 bounding gait characteristic of......" they stands for Otter and Mink, which are beng caompared with the common behaviour of other weasle family hence option D states the same;
Question 3: Only option b is relevant, mentioned in the passsage in latter paragraph.

MKS · Answer

Agree with Enbee11 , nice approach !
IMO Answer : B, D, B

Advices on last 2 are highlighted -

2) The author mentions the "2-2 bounding gait" most probably in order to

Relevant portion of passage is (And I have highlighted hint/supprting words in CAPS) -
LIKE OTHER MEMBERS of the Mustelidae, or "weasel" family, THESE animals have elongated
bodies with long tails and are efficient hunters. On land, THEY commonly employ the 2-2 bounding gait
CHARACTERISTICS OF MUSTELIDAE, as the only semi-aquatic members of the family in the northeast, they are also accomplished swimmers

Thus, here we are describing properties of the Weasel family.it clearly says 2-2 bounding gait characteristic of Mustelidae.
Given that THESE and THEY still point to mink and otter.
Hence "2-2 bounding gait" is certainly a characteristic about Weasel family.

A) Contrast aquatic animals with terrestrial animals.
WRONG - We are discussing just one family - Wesel family. Not aquatic animals Vs. terrestrial animals.

B) Emphasize the energetic efficiency of Mustelidae locomotion.
WRONG - Out of Scope, Twisted Words - efficient hunters is not the same thing as energetic efficiency. energetic efficiency is not discussed in passage.

C) Compare the 2-2 gait to the 1-2-1 loping gait of Mustelidae.
WRONG - Out of Scope - 1-2-1 loping gait Not discussed in passage

D) Describe a behavioral pattern common to the otter, the mink, and other members of the weasel family.
RIGHT - As explained above.

E) specify the placement of Mustelidae forelegs and hind legs when bounding.
WRONG - Out of scope - forelegs and hind legs are not mentioned in passage

3) The passage suggests that Mustela vison

A) is a less important member of the Mustelidae than Lutra canadensis.
WRONG- relative importance not discussed in passage

B) consumes smaller prey than Lutra canadensis.
RIGHT - Supporting portion in passage is -
"subsists largely on fish and
occasional small mammals, whereas the mink prefers
rodents, especially the aquatic muskrat "

C) may be disturbed by the impact of human activity on the environment.

WRONG- Human activity iteslf not discussed in passage

D) has evolved delayed implantation of fertilized eggs.
WRONG- Otter has this not Mink (Mustela vison)

E) is the most gracile of the Mustelidae.
WRONG- Extreme - gracile doesn't mean MOST gracile.

Hope it helps

joshnsit · Answer

Thanks all for the discussion... I have updated the OA and OE from Kaplan for the passage in the initial thread.

I feel that first was easiest(as everyone cracked it) and last one was really a big toughie for everyone(as none of us commented could crack it). I am fine with first 2 questions, but still without direct approach for last question. Let me know any alternate strategies for third question, if stumble across.

Gladiator59 · Answer

The opening line of the passage says-

From this, we can infer that any human disturbance will "render the place inhabitable for minks and otters" as the opposite is mentioned. This is a very small reference but one that can be inferred as it has been explicitly mentioned.

Hope it is clear.

Regards,
Gladi

RahulHGGmat · Answer

Hi  Sajjad1994

Hope you are doing well.

Request you to provide the OE for question number 3.

Many Thanks in advance

kntombat · Answer

Hey,  RahulHGGmat

I think you missed Gladiator59's answer. I think that post above should solve your query.

Sajjad1994 · Answer

Official Explanation

3) The passage suggests that  Mustela vison

Difficulty Level:   750

Explanation

The key to this inference question is  sentence 1:  careful observers along unspoiled shorelines may observe the animals. In other words, if the shore lines have been spoiled or the human observers are not careful, then the animals may not be present or will be harder to observe, implying that their normal behavior has been disturbed.

In  (A) , the phrase  "less important"  is vague in this context. The mink is smaller than the otter, but we have no information about their relative  "importance."  Just because the mink is smaller does not guarantee that it's prey is smaller. Prey is referred to in  paragraph 2 , but no reference is made to size of prey.

(B)  is too vague. Delayed implantation is given as an adaptation of the otter in the context of contrasting its breeding strategies to those of the mink, so presumably the mink has not evolved this strategy. That means  (D)  is out.

And  (E)  is incorrect because the text does not compare the mink to all other members of the  Mustelidae  family.

C is thus correct.

VerbalBot · Answer

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Careful observers of wildlife along unspoiled freshwater shorelines in

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