Guillemots of Arctic regions

[summer beach]

Guillemots are birds of Arctic regions. They feed on fish that gather beneath thin sheets of floating ice, and they nest on nearby land. Guillemots need 80 consecutive snow-free days in a year to raise their chicks, so until average temperatures in Arctic regions began to rise recently, the guillemots' range was limited to the southmost Arctic coast. Therefore, if the warming continues, the guillemots' range will probably be enlarged by being extended northward along the coast.

 

Which of the following, if true, most seriously weakens the argument ?

 

A. Even if the the warming trend continues, there will be still years in which guillemots chicks are killed by an unusually early snow.

 

B. If the Arctic warming continues, guillemots' current prefators are likely to succeed in extending their own range farther north

 

C. Guillemots nest in coastal areas, where temperatures are generally higher than inland areas

 

D. If the Arctic warming continues, much of the thin ice in the southern Arctic will disappear

 

E. The fish the guillemots eat are currently preyed on by a wide variety of predators in the southernmost Arctic regions than they are farther north

 

 

PLS EXPLAIN !! OA will be given after a few posts

[ankitvijay]

Guillemots are birds of Arctic regions. They feed on fish that gather beneath thin sheets of floating ice, and they nest on nearby land. Guillemots need 80 consecutive snow-free days in a year to raise their chicks, so until average temperatures in Arctic regions began to rise recently, the guillemots' range was limited to the southmost Arctic coast. Therefore, if the warming continues, the guillemots' range will probably be enlarged by being extended northward along the coast.

 

Which of the following, if true, most seriously weakens the argument ?

 

A. Even if the the warming trend continues, there will be still years in which guillemots chicks are killed by an unusually early snow.This supports the arguement

 

B. If the Arctic warming continues, guillemots' current prefators are likely to succeed in extending their own range farther north.So what....this doesnt weaken the argument

 

C. Guillemots nest in coastal areas, where temperatures are generally higher than inland areas.Out of scope

 

D. If the Arctic warming continues, much of the thin ice in the southern Arctic will disappear .fish will not be available which is the source of food and hence this weakens the argument...correct

 

E. The fish the guillemots eat are currently preyed on by a wide variety of predators in the southernmost Arctic regions than they are farther north.This supports the argument

[madhur_ahuja]

Agree with D

[summer beach]

D. If the Arctic warming continues, much of the thin ice in the southern Arctic will disappear .fish will not be available which is the source of food and hence this weakens the argument...correct

 

--> thin ice in southern Arctic will disappear, leading to fish decrease in southern Arctic, but not in northern Arctic since nothing is mentioned, so why guillemots can't be enlarged in northen Arctic? :mad:

[ankitvijay]

D. If the Arctic warming continues, much of the thin ice in the southern Arctic will disappear .fish will not be available which is the source of food and hence this weakens the argument...correct

 

--> thin ice in southern Arctic will disappear, leading to fish decrease in southern Arctic, but not in northern Arctic since nothing is mentioned, so why guillemots can't be enlarged in northen Arctic? :mad:

 

Conclusion:if the warming continues, the guillemots' range will probably be enlarged by being extended northward along the coast.

 

Conclusion talks about enlarging of the guillemots range....and if the food si not available due to warming....this wil not happen.........

 

HTH

[kingsingh]

Conclusion:if the warming continues, the guillemots' range will probably be enlarged by being extended northward along the coast.

 

Conclusion talks about enlarging of the guillemots range....and if the food si not available due to warming....this wil not happen.........

 

HTH

 

Agree with ankitvijay. One more point: instead of enlarging, the range will be shifted to northern regions.

[summer beach]

Agreed that food decrease couldn't lead to enlargement .

The argument mentioned food decrease happened in southern arctic, not in northern arctic .

How can it induce food shortage in southern arctic can't lead to enlargement in northern arctic ??

 

Any sounder explaination for this ?

 

OA is D, but my choice is B

[rajatmeh]

Agreed that food decrease couldn't lead to enlargement .

The argument mentioned food decrease happened in southern arctic, not in northern arctic .

How can it induce food shortage in southern arctic can't lead to enlargement in northern arctic ??

 

Any sounder explaination for this ?

 

OA is D, but my choice is B

I think here enlargement is referring to enlargement of area (area covered by birds...where they are living) and you are interpreting to the enlargement of population of birds.

[rupu]

can anybody expln the meaning of this CR pls????? i m very confused!!!!

[romrubiens]

For me D supports the conclusion.

If food sources end up in South, migration will happen to some other direction.

 

IMO B..

 

Need more explanation as why D is right

[venkpeters]

My pick is B

 

The conclusion is "if the warming continues, the guillemots' range will probably be enlarged by being extended northward along the coast.", D says If the Arctic warming continues, much of the thin ice in the southern Arctic will disappea, so it doesnt hamper the conclusion, B says If the Arctic warming continues, guillemots' current prefators are likely to succeed in extending their own range farther north, therefore if the predators expand obviously the conclusion willl be challenged..

[Jun Chen]

Not a specifically hard one but need to read more carefully.