Climate v.s. Human

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Climate v.s. Human

by amysky_0205 » Tue Jan 22, 2013 5:48 am
In Europe, many large animal species, such as mammoths, became extinct soon after humans first migrated to the animals' areas of habitation. The spread of such extinctions closely followed the pattern of human migration. However, since humans tended to migrate to areas as the climate in those areas began to warm, the extinctions might have been precipitated by the climatic warming rather than by human migration.
Which of the following, if true, provides the best evidence that it was human migration and not climatic change that precipitated the extinctions?
A. Many animal species, such as deer and bison, continued to thrive in Europe even after humans migrated there.
B. Several periods of marked climatic warming have occurred in Europe, during which many large animal species that lived there became extinct.
C. Many animal species that became extinct in Europe survived longer in areas that were isolated from human populations but that experienced intense climatic warming.
D. In some areas of Europe, only a few archaeological sites have yielded evidence that shows an overlap between the arrival of humans and the extinction of large animals.
E. Some large animals had become extinct in Europe even before humans migrated there.


OA: C

can someone explain~~~
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by ceilidh.erickson » Tue Jan 22, 2013 7:06 am
The question asks us to support the opposite explanation from the one put for by the argument... in effect, we want to WEAKEN this conclusion. Whenever we want to weaken the conclusion, we have to find the LOGICAL GAP between the premises and the conclusion.

Premises:
- large animals such as mammals became extinct after human migrated to their areas
- spread of extinction and human migration closely correlate
- humans migrate to areas as they become warm

Conclusion:
- extinctions might be because of climate warming

Logical Gap:
This is a CORRELATION/CAUSATION gap. There are three things happening at the same time - extinctions, human migration, and warming. The argument tells us that all of these happen at the same time, then concludes that one (warming) caused another (extinction). If we want to support the other causation structure (human migration caused extinctions), we need another piece of information showing cause and effect... or we need to undermine the first causation structure.

Choice C undermines the causation structure of the conclusion. If some animals survived where the climate was warm but where there were no humans, there must not be a direct link between WARMING and EXTINCTION. The fact that animals did not go extinct in places where there were no humans, but did go extinct in places where there were, strongly implies that HUMAN MIGRATION was the cause of the EXTINCTION.
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by theunheardmelody » Tue Jan 22, 2013 10:18 am
amysky_0205 wrote:In Europe, many large animal species, such as mammoths, became extinct soon after humans first migrated to the animals' areas of habitation. The spread of such extinctions closely followed the pattern of human migration. However, since humans tended to migrate to areas as the climate in those areas began to warm, the extinctions might have been precipitated by the climatic warming rather than by human migration.
Which of the following, if true, provides the best evidence that it was human migration and not climatic change that precipitated the extinctions?
A. Many animal species, such as deer and bison, continued to thrive in Europe even after humans migrated there.
B. Several periods of marked climatic warming have occurred in Europe, during which many large animal species that lived there became extinct.
C. Many animal species that became extinct in Europe survived longer in areas that were isolated from human populations but that experienced intense climatic warming.
D. In some areas of Europe, only a few archaeological sites have yielded evidence that shows an overlap between the arrival of humans and the extinction of large animals.
E. Some large animals had become extinct in Europe even before humans migrated there.


OA: C

can someone explain~~~
thank u !!

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by Diego R. » Tue Jan 22, 2013 12:52 pm
amysky_0205 wrote:In Europe, many large animal species, such as mammoths, became extinct soon after humans first migrated to the animals' areas of habitation. The spread of such extinctions closely followed the pattern of human migration. However, since humans tended to migrate to areas as the climate in those areas began to warm, the extinctions might have been precipitated by the climatic warming rather than by human migration.
Which of the following, if true, provides the best evidence that it was human migration and not climatic change that precipitated the extinctions?
A. Many animal species, such as deer and bison, continued to thrive in Europe even after humans migrated there.
B. Several periods of marked climatic warming have occurred in Europe, during which many large animal species that lived there became extinct.
C. Many animal species that became extinct in Europe survived longer in areas that were isolated from human populations but that experienced intense climatic warming.
D. In some areas of Europe, only a few archaeological sites have yielded evidence that shows an overlap between the arrival of humans and the extinction of large animals.
E. Some large animals had become extinct in Europe even before humans migrated there.


OA: C

can someone explain~~~
thank u !!



In this argument we have 2 attributions. We will call Human Migration = A and Warming = B.

1. Human migration (A) causes the extiction (1st position - Premise)
2. Warming (B) causes the extinction (author´s position - Conclusion)

You are asked to support the 1st position "Human migration causes extinction" and, therefore, weaken the authors position (conclusion). Now, the trick here is that the two premises can happen simultanously, that is, we can have warming and human migration at the same time. We need to ISOLATE each one in order to see their individual effects. The two most common types of answers would be:

Case A) Finding a situation in which A by itself DID NOT cause the attribution (extiction). i.e "warming by itself (without human migration), in other places, did not cause extinction of the local species"
Case B) Finding a situation in which B by itself DID cause the attribution(extinction). i.e. "Human migration by itself (without warming), in other places, caused the extinction of the local species".


Now let´s look at the answer choices (Remember, we want to BLAME Human migration for or EXONERATE Warming from the extinction of species).

A. Supports the conclusion by saying that human migration is harmless. Exonerates Human migration.
B. Blames Warming for the extinction of species.
C. Just what we were looking for in Case A. Exonerates Warming.
D. Inconclusive. Does not blame or exonerate anything.
E. Exonerate Human migration

We have our answer, C.


Hope that helps.

Diego @Gmatteacher
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