Ecologist: Gray wolves were deliberately exterminated from the Greater

Question

Ecologist:  Gray wolves were deliberately exterminated from the Greater Yellowstone Ecosystem by the 1930s, then, in 1995 and 1996, after years of scientific research and public debate, 66 gray wolves from Canada were reintroduced into the Greater Yellowstone Ecosystem. The wolf population expanded rapidly, and wolves were removed from the U.S. Endangered Species list in 2012. Subsequent studies of the Greater Yellowstone Ecosystem documented that elk compose more than 85 percent of wolf kills during the winter. However, preliminary evidence suggests that winter elk mortality has not increased since wolves returned to the Greater Yellowstone Ecosystem in the 1990s.

In the table, select a piece of information that can be reasonably inferred regarding the Wolf population and regarding the Elk population in the Greater Yellowstone Ecosystem based on the information from the passage. Make only two selections, one in each column.

Deepakjhamb · Answer

Wolf population Elk population 
It has never been more prolific in number.
Weak or infirm members are most frequently targeted for predation :  we can never infer such thing from what is given in passage ,so out  
Group size was a major concern for local farmers throughout the 1990s: concerns of farmers are not discussed in passage , so out 
It has long flourished north of the United States border :  we only have inputs about Ecological park , north of United states Border is out of scope , so nothing can be inferred about it  
It was the subject of continued ecological engineering during the 20th century.
Its range has expanded beyond the borders of the ecosystem repeatedly.:  we have inputs only on Ecological park , so expansion in range beyond the the border of ecosystem is out of scope

answer : inference q

wolf population :It was the subject of continued ecological engineering during the 20th century. : explaination : because initially the wolves were deliberately exterminated from the Greater Yellowstone Ecosystem by the 1930s, then, in 1995 and 1996, after years of scientific research and public debate, 66 gray wolves from Canada were reintroduced into the Greater Yellowstone Ecosystemwolves were deliberately exterminated from the Greater Yellowstone Ecosystem . So this is surely continued ecological engineering for wolf population during 20th century

elk population : It has never been more prolific in number. : explaination : the wolves increased tremendously from 1990 to 2012 in the Park , Also elk accounts for 85% of wolf kills (which is substantial) . But we are given that mortality rate of elk never increased since 1990 when wolves were not that high in number . So for sure we now have a tremendous increase in elk population due to which inspite of more number of elk's being killed by more wolves , the mortality rate which is number of elk's killed per hundred remains same due to denominator (the population of elk's being higher than before to compensate). So its very safe to say that elk's poulation has never been more prolific in number in the Ecological park

Sumi1010 · Answer

The given information -
Wolves :
Exterminated by the 1930s.
After 1995-96 research: 66 gray wolves from Canada were reintroduced.
2012 : Wolves were removed from the U.S. Endangered Species list.

Elks :
Elk mortality has not increased since wolves returned in 1990s.

Select a piece of information that can be reasonably inferred regarding the Wolf population and regarding the Elk population in the Greater Yellowstone Ecosystem based on the information from the passage. 
This is an inference based question. The correct choice must be 100% validated from the information provided.
 
WOLF POPULATION
It has never been more prolific in number.
 Can't be inferred as the argument states "The wolf population expanded rapidly" 
Weak or infirm members are most frequently targeted for predation.
 There is no such information to be inferred regarding the kinds of members frequently targeted for the predation.Besides,wolves are supposed, if at all, to be predators. 
Group size was a major concern for local farmers throughout the 1990s.
 There is no such information about the concerns of the farmers. 
It has  long flourished  north of the United States border.
 The information is provided about the extermination and emergence. We don't know if the wolves were long flourished in  north.  
It was the subject of continued ecological engineering during the 20th century.
 Correct. This is supported by the information "after  years of scientific research  and public debate, 66 gray wolves from Canada were reintroduced" 
Its range has expanded  beyond the borders  of the ecosystem repeatedly.
 The all that we know that the wolf population expanded rapidly. Was it within the border or beyond, we don't know.

ELKS POPULATION 
It has never been more prolific in number.
 Correct. Elks mortality increased and then did not (since wolves returned in 1990s). This implies that the population has never been very prolific. 
Weak or infirm members are most frequently targeted for predation.
 There is no such information to be inferred regarding the kinds of members frequently targeted for the predation.  
Group size was a major concern for local farmers throughout the 1990s.
 There is no such information about the concerns of the farmers. 
It has long flourished north of the United States border.
 We don't know if the elks  long  flourished in north of US border. 
It was the subject of continued ecological engineering during the 20th century.
 No, The study on elks started after the elk mortality got increased. 
Its range has expanded beyond the borders of the ecosystem repeatedly.
 It's not true. The elk mortality has increased .

Thus, 
 Wolf Population - It was the subject of continued ecological engineering during the 20th century.
Elks Population - It has never been more prolific in number.

TarunKumar1234 · Answer

It is given that gray wolves got extinctic in 1900s and then 66 nos. brought from Canada in Greater Yellowstone Ecosystem. Gray wolves are predators and their numbers increased. It means, they are protected and got enough food and environment to grow. 85% of Winter Elf (type of Deer) is killed by gray wolves, but mortality rate remains same for Winter Elf. It means, Elves are growing at the same rate as well.

Wolf Population:   It was the subject of continued ecological engineering during the 20th century. (This is the reason, wolves are brought back in Greater Yellowstone)

Elf Population:   It has long flourished north of the United States border. (I am trying to link between increase in population of Winter Elves. I see it is suitable choice)

rocky620 · Answer

Argument Analysis:
 Change in Wolf Population -  First they were killed on purpose in 1930. After debates and scientific research new wolves were introduced in 1995 & 1996. Then the population expanded Rapidly.
Why Were they first killed and then reintroduced - might be to balance the ecological balance.

Change in elk Population -  - They are the main dietary source for wolves (as they compose of 85% of their kills). But Still, since the wolves were reintroduced there was not much change in the mortality.
Why - Might be because they are not reproducing in a heavy manner.

It has never been more prolific in number......  Elk Population  .  Yes. Since they are not producing a lot their mortality has not increased even though they are the main dietary source for wolves.

Weak or infirm members are most frequently targeted for predation...... This would have increased the mortality for elks. We can eliminate. But no such assumptions can be made for wolves, because they were killed deliberately .

Group size was a major concern for local farmers throughout the 1990s...... It does not imply for elks. As, for wolves if the size was concern they would not have been reintroduced.

It has long flourished north of the United States border..... This is an immature choice for wolves. We know that the 66 wolves were from Canada. But we cannot be sure whether they have long flourished the region.

It was the subject of continued ecological engineering during the 20th century......  Wolf Population  .  Yes first they were killed (due to natural imbalances) and then again brought back into existence (again due to natural imbalances). Also, the happening of these instances point out to the fact, that the wolf population was the subject of ecological engineering.

Its range has expanded beyond the borders of the ecosystem repeatedly...... It can be said for wolf population. Butu it only happened once. We have no evidence suggesting that it has happened more than once. As, for elk population not enough evidence in this regard.

Sajjad1994 · Answer

Hello everyone

This is hard question, OA is posted it is:

Wolf population:  It was the subject of continued ecological engineering during the 20th century.
 Elk population:  Weak or infirm members are most frequently targeted for predation.

Note:  We have 2 more days, Points table will be updated soon.

Good luck everyone!

MarcusKar · Answer

Could you please explain the choice for Elk population? I would think it's "It has never been more prolific in number."

LeelaDaka · Answer

Elk population: Weak & infirm elk are anyway gonna contribute to the mortality rate but if such elk are mostly being consumed by the wolf then the mortality rate doesn't vary much.
"it's never been in more prolific numbers" cannot be inferred because "never" is a strong word and also because we don't have enough info in the argument to infer this statement

bumpbot · Answer

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Ecologist: Gray wolves were deliberately exterminated from the Greater

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Wolf population	Elk population
		It has never been more prolific in number.
		Weak or infirm members are most frequently targeted for predation.
		Group size was a major concern for local farmers throughout the 1990s.
		It has long flourished north of the United States border.
		It was the subject of continued ecological engineering during the 20th century.
		Its range has expanded beyond the borders of the ecosystem repeatedly.

GMAT Two-part Analysis (TPA) Questions

Ecologist: Gray wolves were deliberately exterminated from the Greater

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