The stimulus tells us that a tree's age can be determined by counting the annual growth rings in its trunk, each ring representing one year. We also know that the thickness of the ring reveals the relative amount of rainfall that year. The Pazyryk tomb builders "were constrained by tradition to use only logs from trees growing in the sacred Pazyryk Valley."
So, if each log used in the Pazyrk tomb has a distinctive sequence of twelve annual rings representing six droughts years followed by three rainy years and three more drought years, the archaeologists would have been able to successfully use the annual rings to determine the relative ages of ancient tombs at Pazyryk - the tombs clearly having been built at the culmination of a 12 year period where there were six consecutive years of drought, followed by three consecutive years of rain fall, and followed by another three consecutive years of drought.
Hope that was helpful! Let us know if you have any other questions.
(A) is incorrect because it is irrelevant to the passage. We are concerned with explaining the archaeologists' success in using annual rings to establish the relative ages of the tombs at the Pazyryk site. So what would be pertinent is an answer choice that discusses the characteristics of the trunk rings and those rings will help determine the relative ages of the tombs. The tombs being robbed and seepage of water preserving the tombs' remaining artifacts are not pertinent.
(B) is incorrect because it does not help us explain why the archaeologists were successful in using the annual rings to establish the relative ages of the tombs at the Pazyryk site. The trees growing in the Pazyryk Valley having annual rings that are distinct from trees growing in nearby valleys help us identify the origin of the trunks that are being used, but it does not touch upon helping to explain how the archaeologists used the trees to establish the relative ages of the tombs in the Pazyryk site.
(D) is incorrect because it does not help us explain why the archaeologists were successful in using the annual rings to establish the relative ages of the tombs at the Pazyryk site. The trees having an age range between 90 to 450 years does not help in determining the relative ages of the tombs. Remember, we are not concerned with the ages of the trees. We are concerned with determining the relative ages of the tombs, i.e. the ages of the tombs in relation to one another--by using the tree rings.
(E) is incorrect because it does not help us explain why the archaeologists were successful in using the annual rings to establish the relative ages of the tombs at the Pazyryk site. The fact that all of the Pazyryk tombs contain cultural artifacts can be dated to roughly 2300 years ago does not help us determine the relative ages of the tombs, nor does it explain how the rings of the trees were used in helping determine this. This answer choice is irrelevant.
Hope that was helpful! Please let us know if you have any other questions.
BatmanNovember 11, 2015
Thanks a lot!!^^
Briana-SmalleyMay 20, 2019
Can someone please explain why C would be correct?
RaviMay 20, 2019
@Briana-Smalley,
Happy to help.
(C) says, "Each log in the Pazyryk tombs has among its rings a distinctive sequence of twelve annual rings representing six drought years followed by three rainy years and three more drought years."
(C) would definitely help us to show why the rings on the logs provide help in figuring out the ages of the tombs. If there were a distinct pattern of rings that indicates when droughts happened in the past, then we'd be able to trace the ages of the tombs back to the time in which the drought occurred. While we can't know for sure the exact age of the tombs, we have a strong understanding as to what the different tombs' relative ages would be by using the rings, as we'd know the tombs are at least as old as the time of the drought. (C) provides us with an explanation for why the logs allow us to figure out the ages of the tombs. The logs have a unique pattern of rings that tells us when a period of drought and heavy rain occurred, and we can trace the logs back to this time.
Does this make sense? Let us know if you have any more questions!
whlockeJuly 23, 2019
But wouldn't that make it impossible to tell the RELATIVE ages of all the logs? You would only know that they all had been growing at the same time..
IrinaJuly 23, 2019
@whlocke,
The fact that each log in the tombs has among its rings a distinctive sequence of twelve annual rings representing a certain pattern of drought/ rainy years does in fact allow us to determine the relative ages of the tombs. Think about this twelve-ring sequence as a benchmark - let's say a log has 10 rings before it and 10 rings after it, which would put the age of the tree at 10+12+10=32 years. If the archaeologists know the last year of the twelve-ring sequence, they can determine the exact year the tomb was built by adding to that number a number of rings that follow, i.e. in the above example, a final year of the 12-year sequence + 10 years would provide us with the date the tree was cut and used in construction of the tomb.
Let me know if this helps.
Gabby_teixeiraApril 14, 2020
Wouldn't this be a must be true question rather than a paradox? I don't see the discrepancy we're trying to solve here...
BenMingovApril 26, 2020
Hi Gabby, thanks for the question.
I honestly found this question to be super tough when I was going through it during my own preparation. The phrasing of the question clearly marks it as a paradox (contributes most to an explanation), but then I too wondered what the actual discrepancy was.
It seems though, after some consideration, that the actual discrepancy is regarding how archaeologists were able to determine the relative ages of the tombs by using tree rings when tree rings tell them the age of the trees used. Not the age of the tomb itself.
This is the paradox we are trying to resolve.
I hope this helps. Please let me know if you have any other questions or would like me to expand further!
