Recent research indicates that mercury levels in the bodies

Question

Recent research indicates that mercury levels in the bodies of saltwater fish are higher now than they were a hundred years ago. Mercury from the fish accumulates in the base of the feathers of seabirds that eat saltwater fish. Feathers taken from seabirds stuffed and preserved in the 1900s were found to contain only half as much mercury as do feathers recently taken from living birds of the same species.

The argument depends on the assumption that

A) The number of sources of pollutants in 1900s was much lower than it is now.
B) The quantity of mercury found in the body of a saltwater fish depends on the amount of pollution in the ocean habitat of the fish.
C) The same techniques used today were used to stuff and preserve birds in the 1900s.
D) The process used to preserve birds in the 1900s did not substantially decrease the amount of mercury in the birds’ feathers.
E) The Proportion of saltwater fish in the diet of seabirds has remained the same since the 1900s.

Source - Crackverbal

frrcattack · Accepted Answer

I was between D and E.... picked E. My logic in picking E is that the proportion of fish consumption has to be the same, otherwise you cannot compare mercury in seabird diets now to diets in the 1900s. For instance, if seabirds ate far fewer fish in the 1900s but the mercury levels in fish remained the same, that would be a reasonable explanation for why we are seeing more mercury in birds now than in the 1900s. Does that make sense or am I missing something?

bishalpodder · Answer

E is no where related to conclusion whether mercury levels are same or not... put ANT(assumption negation rule) in D, it gives u the assumption

ayushgarg32 · Answer

ravigupta2912 · Answer

Just wondering if LSAT questions are in general more difficult than the ones prepared by test prep companies? I usually get the LSAT Questions wrong but get the ones by test pre companies right.

This answer fit in bang with my pre-thinking which was along the following lines:-

1. Mercury levels haven't changed over time in the preserved fish; OR
2. No other reason for accumulation of mercury on seabird feathers

D fit in with my pre-thinking and was the correct choice. Rest of the choices do not break conclusion when you negate them. B came close but we aren't concerned with the "cause" of increase in mercury but only about the increase.

Palladin · Answer

Where is the conclusion of the argument? Only premises are given.

Abhishek009 · Answer

Absolutely true the stimulus doesn't contain a conclusion, however the hoghlighted part, Research finding on which the entire arguement is conisdered can be safely be taken as the main conclusion that the author/speaker supports....

Pankaj0901 · Answer

I am not able to understand how is "E" wrong. Request experts to please explain "E".

mehro023 · Answer

Hi, I will try to help you out on this. The question stem at no point talks about how much fish do seabirds eat nor does it say how much fish is needed for mercury to accumulate. It makes a general statement that mercury is in saltwater wish and seabirds that eat such fish accumulate mercury on the base of their feathers. In order for E to be true, the stem needs to say something about proportion of fish in the birds diet or something of that nature. Alternatively, if you use negation on both D and E, D completely weakens the conclusion whereas E does not. Let me know if it makes sense.

-K

sparavas · Answer

Mercury levels of feathers preserved from long back are less. 
Mercury levels of seabird feathers from live birds now are more.

What's the difference between the two premises? TIME. What about the time that elapsed? Assumption that authors is that nothing happened while preserving the seabirds feathers (to keep the comparison sane and accurate).

Best option that gives out this logic is D.

laudantiumfacere · Answer

Negated Option E - The proportion of saltwater fish in the diet has not remained the same

This directly means that the number of fishes being consumed is higher/lower than before and we cannot say that mercury levels in fisher are higher now

Option D is correct too

I dont think this question in itself is correct honestly

Recent research indicates that mercury levels in the bodies

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Recent research indicates that mercury levels in the bodies

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