GMATPrep : Years before the advent of plate

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Years before the advent of plate tectonics"•the widely accepted theory, developed in the mid-1960's, the holds that the major features of Earth's surface are created by the horizontal motions of Earth's outer shell, or lithosphere"•a similar theory was rejected by the geological community. In 1912, Alfred Wegener proposed, in a widely debated theory that came to be called continental drift, that Earth's continents were mobile. To most geologists today, Wegener's The origin of Continents and Oceans appears an impressive and prescient document, containing several of the essential presumptions underlying plate tectonics theory: the horizontal mobility of pieces of Earth's crust; the essential difference between oceanic and continental crust; and a causal connection between horizontal displacements and the formation of mountain chains. Yet despite the considerable overlap between Wegener's concepts and the later widely embraced plate tectonics theory, and despite the fact that continental drift theory presented a possible solution to the problem of the origin of mountains at a time when existing explanations were seriously in doubt, in its day Wegener's theory was rejected by the vast majority of geologists.

Most geologists and many historians today believe that Wegener's theory was rejected because of its lack of an adequate mechanical basis. Stephen Jay Gould, for example, argues that continental drift theory was rejected because it did not explain how continents could move through an apparently solid oceanic floor. However, as Anthony Hallam has pointed out, many scientific phenomena, such as the ice ages, have been accepted before they could be fully explained. The most likely cause for the rejection of continental drift"•a cause that has been largely ignored because we consider Wegener's theory to have been validated by the theory of plate tectonics"•is the nature of the evidence that was put forward to support it. Most of Wegener's evidence consisted of homologies"•similarities of patterns and forms based on direct observations of rocks in the field, supported by the use of hammers, hand lenses, and field notebooks. In contrast, the data supporting plate tectonics were impressively geophysical"•instrumental determinations of the physical properties of Earth garnered through the use of seismographs, magnetometers, and computers.

1)The author cites Hallam on the ice ages primarily in order to

(A) provide an example of a geologic phenomenon whose precise causes are not fully understood by geologists today
(B) criticize the geological community for an apparent lack of consistency in its responses to new theories
(C) offer evidence held to undermine a common view of why Wegener's theory was not accepted in its day
(D) give an example of a modern scientist who believes that Wegener's theory was rejected because it failed to adequately explain the mechanical basis of continental drift
(E) support Gould's rationale for why Wegener's theory was rejected by most geologists in the early twentieth century
OA:C

2: The author of the passage refers to the "considerable overlap" between continental drift theory and plate tectonics theory most probably in order to
(A) suggest that plate tectonics theory is derived from Wegener's work
(B) introduce a discussion comparing the elements of the two theories
(C) examine the question of whether continental drift theory was innovative in its time
(D) provide a reason why it might seem surprising that continental drift theory was not more widely embraced by geologists
(E) cite an explanation that has been frequently offered for Wegener's high standing among geologists today

OA:D

3: The author of the passage suggests that the most likely explanation for the geological community's response to continental drift theory in its day was that the theory
(A) was in conflict with certain aspects of plate tectonics theory
(B) failed to account for how mountains were formed
(C) did not adequately explain how continents moved through the ocean floor
(D) was contradicted by the geophysical data of the time
(E) was based on a kind of evidence that was considered insufficiently convincing

OA:E

4: It can be inferred from the passage that geologists today would be most likely to agree with which of the following statements about Wegener's The Origin of Continents and Oceans?

(A) It was a worthy scientific effort that was ahead of its time.
(B) It was based on evidence that was later disproved.
(C) It was directly responsible for the acceptance of the theory of plate tectonics.
(D) It has been disproved by continental drift theory.
(E) It misrepresented how horizontal displacements cause the formation of mountain chains.

OA:A

5: The author of the passage discusses the "essential presumptions" (see highlighted text) of The Origin of Continents and Oceans most in order to

(A) indicate features of Wegener's theory that caused it to be doubted in its day
(B) show why Wegener's theory is now regarded as prescient
(C) indicate differences between plate tectonics and the theory of continental drift
(D) cite features of the theory of continental drift for which no evidence was available in Wegener's day
(E) point out aspects of Wegener's theory that were accepted well before the advent of platetectonics

OA:B

HI Experts,

Can you pls help me with this passage!!!

Thanks
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by ceilidh.erickson » Tue Jan 30, 2018 3:12 pm
When tackling a difficult science RC passage, don't try to understand every detail. Instead, look for the simple overarching story. This will often consist of:
- a theory, and evidence that supports or disproves
- new discoveries / evidence that lead to new understanding
- a disagreement / dispute btw 2 scientists
- an explanation for a paradox / phenomenon

So, let's break down this passage as simply as we can:

I. Years before the theory we currently believe, W proposed a similar theory, but people didn't believe him.

II. Reasons why ppl didn't buy W's theory back then


Let's tackle the questions one at a time.
1)The author cites Hallam on the ice ages primarily in order to

(A) provide an example of a geologic phenomenon whose precise causes are not fully understood by geologists today
(B) criticize the geological community for an apparent lack of consistency in its responses to new theories
(C) offer evidence held to undermine a common view of why Wegener's theory was not accepted in its day
(D) give an example of a modern scientist who believes that Wegener's theory was rejected because it failed to adequately explain the mechanical basis of continental drift
(E) support Gould's rationale for why Wegener's theory was rejected by most geologists in the early twentieth century
First, find the citation in the text:
Most geologists and many historians today believe that Wegener's theory was rejected because of its lack of an adequate mechanical basis. Stephen Jay Gould, for example, .... However, as Anthony Hallam has pointed out, many scientific phenomena, such as the ice ages, have been accepted before they could be fully explained. The most likely cause...
Why did the author include this reference? We were talking about how some geologists & historians think W's theory was rejected for lack of a mechanical basis, but then we introduce Hallam as a pivot. If some scientific theories are accepted before they are fully explained, then we can infer that that's not an adequate explanation for why W's theory was rejected. This author believes that those geologists & historians are mistaken, and that there's a difference reason that W's theory was not accepted.

Now let's analyze the answer choices:

(A) provide an example of a geologic phenomenon whose precise causes are not fully understood by geologists today
We aren't told whether geologists today fully understand ice ages or not. Incorrect.

(B) criticize the geological community for an apparent lack of consistency in its responses to new theories
The word "criticize" is too opinionated. We're not saying "it's wrong to be inconsistent!" We're saying "the fact that there's inconsistency means that that's probably not the real explanation." Incorrect.

(C) offer evidence held to undermine a common view of why Wegener's theory was not accepted in its day
Correct! The reason we bring up Hallam is to offer evidence that those geologists & historians are mistaken.

(D) give an example of a modern scientist who believes that Wegener's theory was rejected because it failed to adequately explain the mechanical basis of continental drift
We don't know if Hallam was actually talking about Wegener. He might have just been talking about ice ages in a different context. Incorrect.

(E) support Gould's rationale for why Wegener's theory was rejected by most geologists in the early twentieth century
Hallam's point was offered in contrast to Gould, not in support. Incorrect.

The answer is C.
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by ceilidh.erickson » Wed Jan 31, 2018 5:47 am
2: The author of the passage refers to the "considerable overlap" between continental drift theory and plate tectonics theory most probably in order to
(A) suggest that plate tectonics theory is derived from Wegener's work
(B) introduce a discussion comparing the elements of the two theories
(C) examine the question of whether continental drift theory was innovative in its time
(D) provide a reason why it might seem surprising that continental drift theory was not more widely embraced by geologists
(E) cite an explanation that has been frequently offered for Wegener's high standing among geologists today
Find the citation in the text, then anticipate an answer:
Yet despite the considerable overlap between Wegener's concepts and the later widely embraced plate tectonics theory, and despite the fact that continental drift theory presented a possible solution to the problem of the origin of mountains at a time when existing explanations were seriously in doubt, in its day Wegener's theory was rejected by the vast majority of geologists.
Why was this considerable overlap mentioned? To emphasize the irony that Wegener's theory was rejected, even though many years later, a very similar theory became the dominant view.

Let's consider the answer choices:

(A) suggest that plate tectonics theory is derived from Wegener's work
No. Overlap in the theories does not necessarily imply that one is derived from the other.

(B) introduce a discussion comparing the elements of the two theories
There is no further discussion after this. The passage does not delve into how specifically these two theories were similar or different. In any event, that's not the PURPOSE of this reference. The purpose was to showcase irony.

(C) examine the question of whether continental drift theory was innovative in its time
Irrelevant value judgment. Whether it was innovative or not, the theory was rejected, but later a similar theory was accepted.

(D) provide a reason why it might seem surprising that continental drift theory was not more widely embraced by geologists
Exactly! The fact that a now-accepted theory is quite similar makes it surprising the CDT wasn't accepted in its time.

(E) cite an explanation that has been frequently offered for Wegener's high standing among geologists today

This is adding outside information that we can't substantiate. We're told that Wegener's document is considered "impressive and prescient," but we don't know about the standing of Wegener himself.

The answer is D.
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by ceilidh.erickson » Wed Jan 31, 2018 5:56 am
3: The author of the passage suggests that the most likely explanation for the geological community's response to continental drift theory in its day was that the theory
(A) was in conflict with certain aspects of plate tectonics theory
(B) failed to account for how mountains were formed
(C) did not adequately explain how continents moved through the ocean floor
(D) was contradicted by the geophysical data of the time
(E) was based on a kind of evidence that was considered insufficiently convincing
Find evidence in the text:
The most likely cause for the rejection of continental drift... is the nature of the evidence that was put forward to support it. Most of Wegener's evidence consisted of homologies... In contrast, the data supporting plate tectonics were impressively geophysical...
The author believes that W's theory was initially rejected because of the type of evidence used to support it.

Now consider the answer choices:

(A) was in conflict with certain aspects of plate tectonics theory
There's no evidence in the text for this. We're told that they largely agree.

(B) failed to account for how mountains were formed
False. Paragraph 1 tells us that W did account for "a causal connection between horizontal displacements and the formation of mountain chains."

(C) did not adequately explain how continents moved through the ocean floor

False. Other authors such as Stephen Jay Gould argue that "continental drift theory was rejected because it did not explain how continents could move through an apparently solid oceanic floor," but this author specifically disagrees with that viewpoint.

(D) was contradicted by the geophysical data of the time
No, we're not told that there was contradictory evidence.

(E) was based on a kind of evidence that was considered insufficiently convincing
Yes, this is perfectly consistent with what we anticipated.

The answer is E.
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by ceilidh.erickson » Wed Jan 31, 2018 6:34 am
4: It can be inferred from the passage that geologists today would be most likely to agree with which of the following statements about Wegener's The Origin of Continents and Oceans?
(A) It was a worthy scientific effort that was ahead of its time.
(B) It was based on evidence that was later disproved.
(C) It was directly responsible for the acceptance of the theory of plate tectonics.
(D) It has been disproved by continental drift theory.
(E) It misrepresented how horizontal displacements cause the formation of mountain chains.


When we're asked to infer, we need to choose an answer that was not explicitly stated, but MUST be true based on what was stated. In the text, we're told:
To most geologists today, Wegener's The origin of Continents and Oceans appears an impressive and prescient document, containing several of the essential presumptions underlying plate tectonics theory...
From this, we can infer that the examples given were all elements of Wegener's theory that are also part of plate tectonics theory. If the document is "impressive and prescient," we can infer that it's well-respected.

(A) It was a worthy scientific effort that was ahead of its time.
We can justify "worthy" based on "impressive and prescient." We can justify "ahead of its time" because all of these ideas were adopted many years later.

(B) It was based on evidence that was later disproved.
False - the passage never states this.

(C) It was directly responsible for the acceptance of the theory of plate tectonics.
"Directly responsible" is far too strong. We aren't given any information about HOW the theory of plate tectonics was formed - it might have been proposed completely independently.

(D) It has been disproved by continental drift theory.
Wegener's theory *is* continental drift theory.

(E) It misrepresented how horizontal displacements cause the formation of mountain chains.

No, we're not given any reason to believe that this was a misrepresentation. In fact, this is cited as one of the elements that Wegener's theory shares with plate tectonics theory.

The answer is A.
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by ceilidh.erickson » Wed Jan 31, 2018 6:51 am
5: The author of the passage discusses the "essential presumptions" (see highlighted text) of The Origin of Continents and Oceans most in order to

(A) indicate features of Wegener's theory that caused it to be doubted in its day
(B) show why Wegener's theory is now regarded as prescient
(C) indicate differences between plate tectonics and the theory of continental drift
(D) cite features of the theory of continental drift for which no evidence was available in Wegener's day
(E) point out aspects of Wegener's theory that were accepted well before the advent of platetectonics


Find the citation in context:
To most geologists today, Wegener's The origin of Continents and Oceans appears an impressive and prescient document, containing several of the essential presumptions underlying plate tectonics theory...
Why were these mentioned? To demonstrate that if Wegener's document also contained these presumptions, then it must have been impressive and prescient.

(A) indicate features of Wegener's theory that caused it to be doubted in its day

No, we're not told that these features specifically made people doubt Wegener's theory.

(B) show why Wegener's theory is now regarded as prescient
Exactly! This perfectly matches our anticipated answer.

(C) indicate differences between plate tectonics and the theory of continental drift
No, these essential presumptions are all similarities, not differences.

(D) cite features of the theory of continental drift for which no evidence was available in Wegener's day
We don't know whether Wegener provided specific evidence for these features or not.

(E) point out aspects of Wegener's theory that were accepted well before the advent of plate tectonics
No, we don't know whether any individual features of Wegener's theory were accepted before plate tectonics. We're just told that his theory as a whole was not accepted.

The answer is B.
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