Source: Platinum GMAT (http://www.platinumgmat.com/practice_gm ... ion_id=617)

On a recent expedition to a remote region of northern Canada, scientists uncovered skeletal remains from about 100,000 years ago. Surprisingly, all the skeletal remains, which included many species from differing biological families and spanned about two thousand years, showed evidence of experiencing temperatures in excess of 1000 degrees Fahrenheit (or 538 degrees Celsius).

Which of the following, if true, best explains the apparent paradox between the cold environment and the evidence of the bones experiencing hot temperatures?

A) Other scientific research released two years before the expedition showed that the remote region of northern Canada underwent considerable warming in the past 100,000 years.
B) Chemical changes that naturally occur during the process of decay in only one north Canadian species produce the same evidence of the species' skeletons being exposed to hot temperatures as the expedition scientists found.
C) A little over 103,000 years ago, a large fire is known to have occurred in northern Canada.
D) Strong evidence exists that as early as 70,000 years ago, Homo sapiens around the world relied heavily on fire to cook animals.
E) In the same expedition and in roughly the same layer of excavation, scientists found rudimentary wood cutting and hunting tools used by early humans.



Cant wrap my head around D (which is the wrong answer) and E (which is the correct one). Please highlight the blank space to see the missing text.

just wrote a massive response and IE crashed...awesome

D deals with a period that is basically irrelevant. we care about 100k years. evidence that we gather from 70k yaers may have zero impact on these remains

E draws conclusion based on something that was found in the same layer of excavation - this implies that whatever that is - it is most relevant since it was exposed to roughly the same conditions as the remains in the stimulus. fire wood + hunting = cooking over open fire = exposed to heat

George, thanks for the reply and may I recommend http://www.mozilla.com/en-US/firefox/fx/ for your microsofty problems :)

Ok, I am going to try to justify D and refute E. Please try and counter my proposed explanation.

The argument states that "scientists uncovered skeletal remains from about 100k years ago"

Option D states that "Strong evidence exists that as early as 70k years ago, HS relied heavily on fire to cook animals".

So from the "bolded" modifiers in the argument and the answer choice, I can claim that the dating of the skeletal remains could have been a few 10k years off. Also, the "as early as" claim could also mean that the discovery of fire could have been earlier than 70k years ago such that the two phenomenon matched?

Option E, don't you think that the conclusion that "fire wood + hunting = cooking" is a BIG leap of faith?

:)

hey

firefox >>>> IE but at work my hands are tied...

as far as D vs. E

the stimulus is concered with the remains from about 100k years so the closer we get to that period, the more of an accurate/relevant conclusion we can draw from whatever it is that we find.

i see how about 100k and as early as 70k seem somewhat close and the gmat is somewhat confusing with these vague descriptions, but i don't think that we can claim that they are similar. you are saying that its off by 10k, but thats 10k years and 1/10th of the whole timeline - actually more now that we are underestimating. do you think that whatever we derive from that will be significant to the stimulus? its not like we are dealing with millions of years and we are 10k years off.

E - true but what else do you suggest. gmat wants us to pick the lest worse or the best answer choice among the options that are given. it will not necessarily be a perfect fit.


from the options that we are given here it seems like the main variables are time and evidence of heat/fire.

D gives us clear evidence of fire but uncertain timeline
E gives us exact timeline to the point where we are certain that the evidence applies precisely to these remains because they were found in the same layer and some evidence of fire

i think time carries more weight here. they could have found a 2 hour movie that shows these skeletons lighting each other on fire, but if it happened in a different time period, it has no relevance to THESE specific skeletons and ultimately no relevance to the conclusion

Hi guys,

Agree with George's explanation fully.

Abhinav, just a word of advice. When you were trying to justify D:


You are questioning the authenticity of the premise. Make sure you never do that on any CR question unless the question is specifically a weaken type (even then, you have to be careful what you weaken). Making an assumption is allowed but not refuting the premise in such a way.

Regards

Sunil

Thank you Sunil and George. All that you guys said makes sense.

Thanks Sunil and George!

_________________
Jamie Nelson
ManhattanGMAT Instructor

Option E states that tool for cutting wood and hunting animals were found. That does not necessarily imply the wood was used to cook animals. There is a possibility where the meat was eaten raw and wood was use for other purpose such as constructing houses, making wooden toys etc.

Option C is the one which states a cause for charred bones. Wouldn't it be correct?

this question is ludicrous. C is no good because it doesn't explain why bones were charred over 2000 years, but E provides no more explanatory power than C. please understand that using practice questions from dubious sources can actually hurt your performance, and be careful which problem sources you use..

_________________
Tim Sanders
Manhattan GMAT Instructor