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Most of the year, the hermit thrush, a North American songbird, eats a

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Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 15 Jul 2015, 02:45
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Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.

Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration‘?


(A) Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.

(B) Insect species contain certain nutrients that are not found in Wild berries.

(C) For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.

(D) Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.

(E) There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

Thrush Migration

Step 1: Identify the Question

The words calls into question indicate that this is a Weaken the Argument question.

Step 2: Deconstruct the Argument

T: usually eat insects

But migrate eat berries even tho fewer cal

Ó Berries nec nutrients

Step 3: Pause and State the Goal

On Weaken questions, the correct answer makes the conclusion less likely to be valid. The conclusion in this argument is a possible explanation for the thrush’s feeding behavior. One way to weaken this conclusion is to provide an alternative reason for this behavior.

Step 4: Work from Wrong to Right

(A) This information explains why nutrition is important for the thrush during migration. It does not, however, address why the thrush eats berries instead of insects.

(B) This answer provides another reason it might be better for thrushes to eat insects (other specific nutrients). It does not provide an alternative reason as to why thrushes eat berries.

(C) CORRECT. This answer provides an alternative reason that thrushes might choose to eat berries instead of insects while migrating: They don’t want to expend extra energy catching the insects. Even though the berries contain fewer calories, the thrushes might actually have a net gain of calories since they don’t have to chase and capture the berries.

(D) If insects are very abundant along the migration route but the thrush still prefers berries, then the conclusion is more likely to be valid, not less.

(E) The argument states that thrushes do eat berries while migrating. The fact that they do not eat all types of berries does not influence the explanation as to why they eat some berries.
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 16 Jul 2015, 10:04
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Premise - Hermits feed on insects most of the times but during migration they feed on wild berries though wild berries are not as rich in calories as insects are and Hermits require plenty of calories during migration.
Conclusion - Berries contain other nutrients that Hermits need for migration and that insects lack.

If we want to weaken the conclusion we should look for a choice which provides an alternate reason as to why the Hermits prefer eating berries during Migration.


There could be various reasons one can think of
- It is possible that no insects are available that the Hermits can eat during migration.
- Or some other reason.

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.
- There is not mention of undernourishment in either the premise or the conclusion. This statement does not affect the conclusion in any way.

B. Insect species contain certain nutrients that are not found in Wild berries.
- This statement too does not affect the conclusion. Even if Insect species contain certain nutrients that are not found in berries , this choice does not provide any reason as to why the hermits prefer berries to insects during migration.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.
- This choice provides an alternate reason to the fact that hermits prefer berries. If catching insects requires significantly more calories than catching wild berries does then the hermits by choice have berries because they would want to conserve energy during their migration.

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.
- Does not provide any reason as to why hermits prefer berries.

E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.
- Does not affect the conclusion. Even if there are some species that are rich and hermits do not eat them this choice does not provide any alternate cause.
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 15 Jul 2015, 21:25
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NA song bird diet mainly consist of insects

In autumn they migrate to Central and South America where their
diet is exclusively wild berries

wild berries are low in calories

the possible reason could be it has some other nutrients that they need for migartion that insect lacks.Conclusion


we have to find a reason other than nutrients to explain the birds eating habit.


Option C : this gives a counter opinion for the conclusion ,since the calories expelled was more for insect catching , the birds feed on wild berries
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 14 Jun 2016, 08:01
akhil911 wrote:

Premise - Hermits feed on insects most of the times but during migration they feed on wild berries though wild berries are not as rich in calories as insects are and Hermits require plenty of calories during migration.
Conclusion - Berries contain other nutrients that Hermits need for migration and that insects lack.

If we want to weaken the conclusion we should look for a choice which provides an alternate reason as to why the Hermits prefer eating berries during Migration.


There could be various reasons one can think of
- It is possible that no insects are available that the Hermits can eat during migration.
- Or some other reason.

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.
- There is not mention of undernourishment in either the premise or the conclusion. This statement does not affect the conclusion in any way.

B. Insect species contain certain nutrients that are not found in Wild berries.
- This statement too does not affect the conclusion. Even if Insect species contain certain nutrients that are not found in berries , this choice does not provide any reason as to why the hermits prefer berries to insects during migration.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.
- This choice provides an alternate reason to the fact that hermits prefer berries. If catching insects requires significantly more calories than catching wild berries does then the hermits by choice have berries because they would want to conserve energy during their migration.

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.
- Does not provide any reason as to why hermits prefer berries.

E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.
- Does not affect the conclusion. Even if there are some species that are rich and hermits do not eat them this choice does not provide any alternate cause.


Hi,

Option D might also say that since insects are present through out the migration routes, birds will eat insects along the route since they started with less energy by eating berries initially. Can you please help me understand what I am missing.
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 14 Jun 2016, 10:03
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WillGetIt wrote:
Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.

Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration‘?



Thrush : Most of the year---> Insects
Thrush : Autumn ------------> Wild Berries
Calories : Wild Berries < Insects
So , Thrushes need plenty of Wild Berries to complete their migration.
Possible reason : Berries contain other nutrients not found in Wild Berries


Prethink : What's the reason that Thrushs consume only Wild Berries not Insects during migration ? Check the answers -

A. Hermit thrushes, [color=#ff0000]if undernourished, are unable to complete their autumn migration before the onset of winter.

Out of scope , this options talks about undernourishment.

B. Insect species contain certain nutrients that are not found in Wild berries.

Out of scope , this options talks about other nutrients which is not under discussion in the present context.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.

Calorie Used : Catching Insects > Eating wild berries ; for same calorific intake...

Say 10 KCAL of Energy is consumed ...

Catching Insects = 4KCAL
Eating wild berries = 3 KCAL
Energy Requirement for flight = 5KCAL

Keeping in mind that the bird requires energy for flight it is definitely beneficial for the bird to use it economically and consume high calorie food/nutrients...

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.

So, why do the birds not catch insects ? Can not weaken the conclusion.

E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

Completely out of scope and irrelevant under present context..

Hence IMHO definitely with (C)

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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 15 Jul 2016, 04:28
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C is the unopposed winner

Insect gives 100 calorie; Catching insect requires bird to lose 40 calorie. (Finding insect, Flying, then chasing insect, then breaking its shell).
Birds net calorie gain from insect 100-40=60 calorie

Berries gives only 80 calories, But finding berry requires 10 calorie. Find a tree and hop and hop and eat as much as you like without any problem.
Birds Calorie gain from berries 80-10=70 calorie.

Therefore the songbird eats only berries to gain as much calorie as they can. Chasing and catching insect is not viable for songbirds.
What option reconfirms our conclusion

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.


WillGetIt wrote:
Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.

Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration‘?

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.

B. Insect species contain certain nutrients that are not found in Wild berries.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.

E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 15 Jul 2016, 05:21
Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.

Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration‘?

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.

General statement, no impact on the explaination given in argument.

B. Insect species contain certain nutrients that are not found in Wild berries.

This tells there are certain nutrients in insects, but doesn't say the ammount of nutrients is more than berry.
No impact

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.

This tells, if birds catch insects they the energy expenditure is more than if they eat berry

This gives a reason to think that to conserve energy expenditure, birds eat berry

Z causes Y

Weakens

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.
This tells that insects are in abundance during migration period but doesn't tells about the feeding behaviour. Irreverent because explanation given above says because of high nutrients in berry ,birds eat them.
E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories. Out of scope
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 19 Dec 2016, 21:27
WillGetIt wrote:
Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.

Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration‘?

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.

B. Insect species contain certain nutrients that are not found in Wild berries.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.

E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

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ChiranjeevSingh , Why is option D wrong here ? If birds find insects on route , then probabaly the calories gained to complete migration are not from berries but from Insects.

Although C is a promising answer , question specifically asks for diet's during migration ? While option C indicated the situation before Migration. Also when birds about to start their journey, they need to accumulate certain value of calories say 100J , no matter how much they spend calories during accumulation process.

Please help !
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 20 Dec 2016, 00:18
AbhiGarg2007 wrote:
Why is option D wrong here ? If birds find insects on route , then probabaly the calories gained to complete migration are not from berries but from Insects.


Option D is wrong because OG says so! :P

The point we are trying to explain here is why don't they eat insects in autumn. Right? We are not saying that they don't eat insects in North America; we are saying that they don't eat insects at all in autumn! And now option D tries to explain so by saying that they have insects during their routes! Wow! Then, why don't they eat them? We're stuck on the same question!

AbhiGarg2007 wrote:
Although C is a promising answer , question specifically asks for diet's during migration ?

While option C indicated the situation before Migration.


Nowhere does option C indicate that it is about "before migration". or am I missing something?

AbhiGarg2007 wrote:
Also when birds about to start their journey, they need to accumulate certain value of calories say 100J , no matter how much they spend calories during accumulation process. Please help !


Is it? Energy expended doesn't matter? If you eat 100J and spend 100J, then how much do you have left?

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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 24 Dec 2016, 03:38
ChiranjeevSingh wrote:
AbhiGarg2007 wrote:
Why is option D wrong here ? If birds find insects on route , then probabaly the calories gained to complete migration are not from berries but from Insects.


Option D is wrong because OG says so! :P

The point we are trying to explain here is why don't they eat insects in autumn. Right? We are not saying that they don't eat insects in North America; we are saying that they don't eat insects at all in autumn! And now option D tries to explain so by saying that they have insects during their routes! Wow! Then, why don't they eat them? We're stuck on the same question!

AbhiGarg2007 wrote:
Although C is a promising answer , question specifically asks for diet's during migration ?

While option C indicated the situation before Migration.


Nowhere does option C indicate that it is about "before migration". or am I missing something?

AbhiGarg2007 wrote:
Also when birds about to start their journey, they need to accumulate certain value of calories say 100J , no matter how much they spend calories during accumulation process. Please help !


Is it? Energy expended doesn't matter? If you eat 100J and spend 100J, then how much do you have left?

- CJ



Got it CJ !!!

So my explanation now as follows:-

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does. (Correct)

As before migration to C&S America, birds need to accumulate enough calories, so as their time for migration approaches, they start eating exclusively berries to accumulate calories.

It means Berries have something special other than calories which help them to complete their migration.

Now to weaken argument, we need to establish that it is the calories which they gain and require for completion of migration.

This choice correctly establishes that feeding on berries provides them more calories as they need not to spend the same on picking berries than
hunting insects

So it is none other than calories they gain from Berries in order to complete migration.

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.

But they have already stopped eating insects so what would they do with the insects?
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 14 Jan 2017, 01:57
akhil911 wrote:

Premise - Hermits feed on insects most of the times but during migration they feed on wild berries though wild berries are not as rich in calories as insects are and Hermits require plenty of calories during migration.
Conclusion - Berries contain other nutrients that Hermits need for migration and that insects lack.

If we want to weaken the conclusion we should look for a choice which provides an alternate reason as to why the Hermits prefer eating berries during Migration.


There could be various reasons one can think of
- It is possible that no insects are available that the Hermits can eat during migration.
- Or some other reason.

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.
- There is not mention of undernourishment in either the premise or the conclusion. This statement does not affect the conclusion in any way.

B. Insect species contain certain nutrients that are not found in Wild berries.
- This statement too does not affect the conclusion. Even if Insect species contain certain nutrients that are not found in berries , this choice does not provide any reason as to why the hermits prefer berries to insects during migration.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.
- This choice provides an alternate reason to the fact that hermits prefer berries. If catching insects requires significantly more calories than catching wild berries does then the hermits by choice have berries because they would want to conserve energy during their migration.

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.
- Does not provide any reason as to why hermits prefer berries.

E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.
- Does not affect the conclusion. Even if there are some species that are rich and hermits do not eat them this choice does not provide any alternate cause.



"eating" wild berries..and not "catching"...threw me off a bit originally :P
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 24 Mar 2017, 12:08
Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.

they feed almost exclusively on wild berries , berries are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration.

"possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack."
Ask is- what suggests the requirement is not nutrients / calories , i.e., it is something different.


Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration‘?

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.
irrelevant.
B. Insect species contain certain nutrients that are not found in Wild berries.
not a concern.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.
that is one reason which suggests - requirement is not nutrients / calories. it is something different.
Correct.
D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.
Irrelevant.

E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

some species of wild berries ? does not matter. no mention.
overall it does not suggest anything apart from nutrients/ calories.
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 02 Aug 2017, 07:54
LogicGuru1 wrote:
C is the unopposed winner

Insect gives 100 calorie; Catching insect requires bird to lose 40 calorie. (Finding insect, Flying, then chasing insect, then breaking its shell).
Birds net calorie gain from insect 100-40=60 calorie

Berries gives only 80 calories, But finding berry requires 10 calorie. Find a tree and hop and hop and eat as much as you like without any problem.
Birds Calorie gain from berries 80-10=70 calorie.

Therefore the songbird eats only berries to gain as much calorie as they can. Chasing and catching insect is not viable for songbirds.
What option reconfirms our conclusion

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.


WillGetIt wrote:
Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.

Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration‘?

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.

B. Insect species contain certain nutrients that are not found in Wild berries.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.

E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

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But it could be the following case?
Birds net calorie gain from insect 100-40=60 calorie
Birds Calorie gain from berries 80-25=55 calorie.

How should we understand "significantly more"? in the above the calculation, i change the consumption of eating wild berries to a bit more, then the whole calculation is different.
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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WillGetIt wrote:
Most of the year, the hermit thrush, a North American songbird, eats a diet consisting mainly of insects, but in autumn, as the thrushes migrate to their Central and South American wintering grounds, they feed almost exclusively on wild berries. Wild berries, however, are not as rich in calories as insects, yet thrushes need to consume plenty of calories in order to complete their migration. One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack.

Which of the following, if true, most seriously calls into question the explanation given for the thrush’s diet during migration‘?

A. Hermit thrushes, if undernourished, are unable to complete their autumn migration before the onset of winter.

B. Insect species contain certain nutrients that are not found in Wild berries.

C. For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.

D. Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.


E. There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

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The logic of the question is why the birds prefer to eat wild berries when they need very large amounts of energy while migrating .
We have show that this particular behavior is the most efficient one


C gives us the reason why birds prefer to eat wild berries when they migrate they reduce their energy by not catching insects .

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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 29 Aug 2017, 10:15
My ques
A causes B can be weaken by C causes B
C causes B ok

see the option C
what if
calorie reqd to catch insect = 200
calorie gained from eating = 400
net gain = 200.

calorie reqd to eat berry = 100
calorie gained = 200
net benifit= 100

since 200>100 we can not use it to prove that berries eating will be more calorific as compared to eating insects.

kindly clear this doubt.. thanks in advance.
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 04 Jul 2018, 20:52
Can you explain why options D and E are wrong and C is correct?
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 10 Jul 2018, 09:15
Lowkya wrote:
Can you explain why options D and E are wrong and C is correct?

Let's review the situation:

  • The birds need plenty of calories in order to complete their migration.
  • Berries are not as rich in calories as insects.
  • If the birds need lots of calories and insects are higher in calories, why do the birds eat berries during migration instead of insects??
  • "One possible explanation is that berries contain other nutrients that thrushes need for migration and that insects lack."

We are looking for an answer choice that calls this explanation into question. We don't need to prove that the explanation in the passage is false. However, if one of the answer choices provides a plausible alternative explanation, then that would cause us to doubt the explanation given in the passage.

Quote:
(C) For songbirds, catching insects requires the expenditure of significantly more calories than eating wild berries does.

Remember, the birds need plenty of calories. We know that insects are higher in calories, but now we are told that the birds expend significantly more calories getting those calories from the insects. So even though the insects are high in calories, the birds have to waste a lot of calories catching the insects. If the goal is to achieve the highest net balance of calories, then the birds might be better off eating the berries.

Again, we don't need to prove that eating berries will lead to a higher net balance of calories. But this is certainly a plausible explanation for the phenomenon described in the passage. Since we now have a plausible alternative explanation, the explanation given in the passage is certainly called into question. (C) looks good.

Quote:
(D) Along the hermit thrushes’ migration routes, insects are abundant throughout the migration season.

We are trying to explain why the birds eat berries instead of insects. If the insects were NOT abundant, that might explain why the birds eat berries. But if the insects ARE abundant, then the birds should have no problem finding them. So why are they eating berries instead? Choice (D) does not explain the apparent discrepancy, so eliminate this one.

Quote:
(E) There are some species of wild berries that hermit thrushes generally do not eat, even though these berry species are exceptionally rich in calories.

(E) simply tells us that the birds avoid some high-calorie berries. But we already know that the birds eat berries during migration and that the berries are lower in calories than insects. (E) does not explain why the birds chose the lower-calorie option, so eliminate this one.

(C) is the best answer.
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Re: Most of the year, the hermit thrush, a North American songbird, eats a  [#permalink]

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New post 18 Sep 2018, 13:09
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What i need to find - During Migration Thrush doesn’t eats wild berries just because berries got more other nutrients .

option Analysis -
A. Where is berries explanation
B. ok still why berries ?
C. That explains
D. then why berries ?
E. some right… May be exceptions here
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Re: Most of the year, the hermit thrush, a North American songbird, eats a &nbs [#permalink] 18 Sep 2018, 13:09
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