By examining fossilized beetles a research team has produced the most

Question

By examining fossilized beetles a research team has produced the most detailed description of temperatures in Britain over the past 22,000 years. Fossils of species that still exist were selected and dated. When individuals of several species found in the same place were found to date to the same period, the known temperature tolerances of the existing beetle species were used to determine the maximum summer temperature that could have existed at that place and period.

The procedure of the researchers assumes which one of the following?

(A) Beetles can tolerate warm weather better than cold weather.

(B) Fossils of different species found in the same place belonged to different periods.

(C) The process of dating is more accurate for beetles than for other organisms.

(D) The highest actual summer temperature at a place and period equaled the average of the highest temperatures that could have been tolerated by each of the beetle species found there and dated to that period.

(E) The temperature tolerances of the beetle species did not change significantly during the 22,000-year period.

GMATNinja · Accepted Answer

Let's break down the "procedure of the researchers" as described in the passage:

First, they found fossils of species of beetles that still exist, and determined the date of those fossils. 
 Then they narrowed their scope to cases in which "individuals of several species found in the same place were found to date to the same period." 
 Then, they used the "known temperature tolerances" of the species (which they know because the species exist in the current day) to determine what the maximum summer temperature could have been at the time when the fossilized beetles lived.

So, the researchers applied information about  existing  beetle species to  fossils of the same species  to produce "the most detailed description of temperatures in Britain over the past 22,000 years."

To answer the question, we need to find an assumption made by the researchers in this procedure. Let's look at the answer choices:
 
The passage gives us no information about how well the beetles tolerate either cold or warm weather, and the researchers certainly did not have to assume that they tolerated one better than the other. (A) is out.

The researchers only focused on cases in which "individuals of several species found in the same place were found to date to the  same  period." This is the opposite of the information in answer choice (B), so (B) is not an assumption made by the researchers.

The passage does tell us that dating beetles has produced "the most detailed description of temperatures in Britain over the past 22,000 years." But do the researchers have to assume that the process of dating is more accurate for beetles than other organisms?

No, they do not. The procedure used by the researchers would not be impacted in any way if all organisms could be accurately dated -- it is only necessary that the beetles  can  be accurately dated. (C) is out.

It really doesn't make sense that the highest actual temperature would be the  average  of the highest tolerated temperatures for the species that existed in that time and place.

Take this example: The fossils of two existing species are found in one location and dated to the same time period. One species can tolerate temperatures up to 100 degrees, and the other can only tolerate temperatures up to 60 degrees. Using the information in answer choice (D), the highest actual temperature would have to be 80 degrees -- which is impossible, because then the second species would not have been able to exist in that time period. (D) is out.

Now look at (E):
 
The researchers use the temperature tolerances of beetles that  exist today  to determine what the maximum temperatures could have been over the past 22,000 years. So, the researchers must assume that the temperature tolerances of these beetle species have not changed significantly over this time period. (E) is the correct answer.

I hope that helps!

GMATNinja · Answer

And here's a video explanation. Enjoy!

https://www.youtube.com/watch?v=zuaNK9chDuA

adityapareshshah · Answer

Hi,

Can anyone provide the OE?
 
The research will make sense only if Option 4 is true.
Negating 4, breaks the argument. Am I correct?

CrackverbalGMAT · Answer

Simplify the argument -

fossils of species that still exist were selected and dated --> the known temperature tolerances of the existing beetle species were used to determine the maximum summer temperature that could have existed at that place and period .

Option A - Incorrect.
No such assumption is required to measure the maximum summer temperature. Even if they could tolerate cold temperatures better, the argument still stands.

Option B - Incorrect.
Not true. look at what the argument says - 
" When individuals of several species found in the same place were found to date to the same period ... "

Option C - Incorrect.
We cannot make this assumption as we do not have data about other organisms.

Option D - Incorrect.
Not true. The highest temperature was probably the lowest among the temperatures that those different species could tolerate. Otherwise, the species who had a tolerance below the average could not have survived.

Option E - Correct answer.
If it did change, we can no longer hypothesize about the past conditions through the present because the data would no longer be comparable.

SeregaP · Answer

p: beetles are found, dated and groupped
C: now by using some data researchers can identify the temperature
E is fine, because if the temperature tolerance would have changed, the results would be inaccurate

sananoor · Answer

E it must be, Suppose A's maximum temperature tolerance in last 22000 years is estimated to be 96 Celsius. But if temperature tolerance of A initially were 150 Celsius and then changes to 96...then researches wont be able to find out most extreme temperature of that place. 
So writer assumes that the change in temperature tolerance didn't change significantly. it might ranges from 105 to 95 and that is normal.

mykrasovski · Answer

Could someone please explain? I don't really follow the explanations which were provided in this post so far...

TheNightKing · Answer

This is new! Awesome!!!

auradediligodo · Answer

Pre-thinking

Assumption question

We know that researchers used fossils of beetles to understand the history of temperatures in a period of 22000 years. Furthermore researchers only used fossils of beetles that still leave. Once they were able to locate a period, researchers would just look at the temperature tolerance of the current beetles to infer the temperature related to the fossils' period.

Now let's find the assumptions here.

Falsification scenario#1  : What if such beetles lived in places that did not reflect the right temperature? What if they lived in a cave that was cooler than the outside temperature for example. The argument would break under these circumstances because the research would not be accurate anymore.

Falsification scenario#2  : What if the tolerance changed over the years? Then the results would be flawed

Assumption#1  : such beetles lived in places that did reflect the right temperature

Assumption#2  :the tolerance did not change over the years

POE

(A) Beetles can tolerate warm weather better than cold weather. 
 Irrelevant

(B) Fossils of different species found in the same place belonged to different periods. 
 irrelevant

(C) The process of dating is more accurate for beetles than for other organisms. 
 irrelevant

(D) The highest actual summer temperature at a place and period equaled the average of the highest temperatures that could have been tolerated by each of the beetle species found there and dated to that period. 
 This is not a must be true statement. OUT

(E)   The temperature tolerances of the beetle species did not change significantly during the 22,000-year period.
 In line with our pre-thought  assumption#2

DVR17 · Answer

ARGUMENT: FOSSILIZED BEATLES EXAMINED BY REASEACHESR AND PRODUCED THE DETAILS TEMP REPORT. BEATLES SPECIES STILL EXIST WERE SELECTED THESE BEATLES DATED TO THE SAME PERIOD FOUND THE MAX SUMMER TEMP IN TAHT PLACE AND PERIOD

A) doesn't matter even if they do

B) but we are examining the same species and we don't care about other species

C) out of scope

D) didn't understand

E) if this is the cases then this has to be our assumption coz if the temp didn't change significantly that is the only reason we are using species that still exist

Danish234 · Answer

Can someone explain what this sentence means, "individuals of several species found in the same place were found to date to the same period."?

GMATNinja · Answer

That sentence means that a number of fossils -- fossils of a few different types of beetles -- were analyzed and found to be the same age.

As an example: perhaps the scientists found 2 rock beetle fossils and 3 dung beetle fossils in the same place, and all 5 fossils were found to be 300 years old.

I hope that helps a bit!

VerbalBot · Answer

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By examining fossilized beetles a research team has produced the most

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