A popular beach has long had a dolphin feeding program in which fish a

Question

A popular beach has long had a dolphin feeding program in which fish are given to dolphins several times a day; many dolphins get as much as half of their food each day there. Although dolphins that first benefit from the program as adults are healthy and long-lived, their offspring have a lower life expectancy than offspring of dolphins that feed exclusively in the wild.

Which of the following, if true, most helps to explain the lower life expectancy of offspring of dolphins feeding at the beach compared to other young dolphins?

(A) Sharks that prey on dolphins are less common in the open seas off the beach than in many other areas of the open seas where dolphins congregate.

(B) Many of the adult dolphins that feed at the beach are females that nurse their offspring there.

(C) The fish given to the dolphins at the beach are the same types of fish that dolphins typically catch in the wild.

(D) Many dolphins that feed at the beach with their offspring come to the beach only a few times a month.

(E) Adult dolphins that feed at the beach spend much less time teaching their offspring how to catch fish in the wild than do other adult dolphins.

KarishmaB · Accepted Answer

Fish are given to dolphins several times a day; many dolphins get as much as half of their food each day there.
Dolphins that first benefit from the program as adults are healthy and long-lived, but their offspring have a lower life expectancy than offspring of dolphins that feed exclusively in the wild.

This is a kind of 'explain the paradox' question. You expect the offspring of all dophins to have similar life expectancy. You might even think that dolphins who feed at the beach and their offspring might, in fact, have better life expectancy than others since half of their daily need is supplied by the beach. But actually offspring of dolphins that feed at the beach have lower life expectancy!

What will explain this?

A. Sharks that prey on dolphins are less common in the open seas off the beach than in many other areas of the open seas where dolphins congregate.

If the number of predators is lower near the beach, it should increase the life expectancy of the dolphin offsprings, not decrease it. Not correct.

B. Many of the adult dolphins that feed at the beach are females that nurse their offspring there.

This should increase the life expectancy of the dolphin offsprings since they get half their food from the beach program. Not correct.

C. The fish given to the dolphins at the beach are the same types of fish that dolphins typically catch in the wild.

This also implies that the life expectancy of the dolphin offsprings should not be any lower. Not correct.

D. Many dolphins that feed at the beach with their offspring come to the beach only a few times a month.

This doesn't explain why the life expectancy of the offspring of these dolphins should be lower. Perhaps, if they come to the beach only a few times a month, the beach has no importance for them. But then, why should their offspring have lower life expectancy? The others make do with the fish from the wild - they can do so too.

E. Adult dolphins that feed at the beach spend much less time teaching their offspring how to catch fish in the wild than do other adult dolphins.

This explains the paradox perfectly. Adult dolphins that are busy at the beach don't teach fishing to their offspring. This means that the offspring don't learn how to make up the other half of their daily diet. The fish at the beach provide only half of their diet. They don't learn how to catch fish in the wild and make up the day's quota. On the other hand, the dolphins sticking to the wild spend time teaching fishing to their offspring and hence the life expectancy of their offspring is higher.

Answer (E)

Mackieman · Answer

My first thought when having read the text was:
Is the lower life expectancy based on their offspring not being able to feed themselves or due to shark attacks?

A) Opposite explanation, they would have longer life expectancy not shorter
B) Irrelevant
C) No point
D) Irrelevant
E) Solid and clear explanation to the life the lower life expectancy.

Answer: E

vjsharma25 · Answer

A. Sharks that prey on dolphins are less common in the open seas off the beach than in many other areas of the open seas where dolphins congregate.
 It actually gives another reason that live expectancy should be more. 
B. Many of the adult dolphins that feed at the beach are females that nurse their offspring there.
 Same as A. 
C. The fish given to the dolphins at the beach are the same types of fish that dolphins typically catch in the wild.
 Then life life expectancy should be same(provided amount of food is also same). Doesn't explain the difference though. 
D. Many dolphins that feed at the beach with their offspring come to the beach only a few times a month.
 Irrelevant as it also Doesn't explain the difference. 
E. Adult dolphins that feed at the beach spend much less time teaching their offspring how to catch fish in the wild than do other adult dolphins.
 This can be the reason why they are not healthy and have lower life expectancy.Because they are only dependent on the 1/2 of their diet on the food provided through the feeding program.So for another half they have to make effort.And if they don't know how to get the food the live expectancy will decline

manojISB123 · Answer

Hello Karishma,

Just for the sake of clarity and to ensure that we are rejecting option 'A' for right reasons. In option A you mentioned "predators is lower  near the beach " but in actual answer choice it says "  open seas off the beach  ". I think "  open seas off the beach  " is an area far away from beach and not near? Please comment.

Thanks
Manoj Parashar

KarishmaB · Answer

"open seas off the beach" means they are talking of waters close to the beach.

manojISB123 · Answer

Thanks for reply. But as far i understand the contextual/literal meaning of  Off  is away/at distance (Just checked/confirmed on Google.Can not post link as I don't have 5 post yet). I understand it is quite small thing but just trying to understand how "OFF" in this context could mean close?
You may like to use any examples to explain.

Thanks

KarishmaB · Answer

Important is the meaning of the phrase, not of individual words. 
Quite often the phrase is used in this way "...the rock formation just off the beach...". It means next to the beach. 'The waters off the beach' means the waters next to the beach. That is how you differentiate 'waters close to the beach' from 'waters far away from the beach'.

Probably, insertion of the word 'just' would have made the intent clearer but we cannot change the options.

kooks123 · Answer

There are multiple usages of "off" as a preposition and as an adverb. All usages are explained with examples under the following link:

https://www.collinsdictionary.com/dicti ... lish/off_1

All your doubts regarding "off" will be cleared. Thank you.

VerbalBot · Answer

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A popular beach has long had a dolphin feeding program in which fish a

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A popular beach has long had a dolphin feeding program in which fish a

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