Although much has been written about the theological conflicts with

Question

Although much has been written about the theological conflicts with Darwinian theory, little is known of the powerful scientific objections that modified Darwin’s beliefs.

During Darwin’s lifetime, the accepted theory of heredity was not Mendel’s theory of particulate inheritance, which, though published, was unrecognized, but the theory of blending inheritance, which holds that forms intermediate between those of the parents result from mating. Jenkin pointed out that if a rare and favorable mutation occurred, it would soon be blended out by repeated crossings from the  wild-type  form. Disputing Darwin’s conception of evolution as proceeding through the natural selection of those with slightly better characteristics that arose randomly, Jenkin concluded that natural selection could not account for the tremendous diversity of life, hypothesizing that large numbers of organisms mutated simultaneously in the same direction—a controlled orthogenetic process resembling a series of “special creations.”

Since “special creationism” was an ideological target of his, Darwin found himself in a quandary. Although he did not abandon his theory, he admitted that natural selection played a much smaller part in evolution than he had previously claimed. He also embraced the Lamarckian concept that acquired traits in parents are transmitted to their offspring, thus providing a mechanism by which an entire population could change in the same direction at once.

Another potent objection came from the physicists led by Lord Kelvin, who contested the assumption of previous geologists and biologists that life had existed for billions of years, if not infinitely. How, they asked, could evolution proceed by slow steps in millions of years, and how could advanced forms recently evolved show such great differences? The Kelvinists, basing their conclusion on the assumption that the sun was an incandescent liquid mass rapidly radiating heat, calculated that the age of the earth was between 20 and 40 million years.

Admitting that their calculations were correct and their premises rational, Darwin was forced to adjust this theory. He proposed that change had occurred much more rapidly in the past than in the present, where species seemed static, and that more advanced forms varied more rapidly than lower forms. This provided further reason to advocate Lamarck’s theory of inheritance, because that could account for the rapid change.

Interestingly, both these retreats of Darwin were later shown to be faulty. The discovery that the sun runs on a nearly infinite amount of atomic fuel totally invalidated Kelvin’s argument, Mendel was “ rediscovered ” in the twentieth century, when it was pointed out that the particulate nature of inheritance meant that favorable mutation not only could persist, but could rapidly become prevalent.   1 
 1. The primary purpose of the passage is to

A. Outline the process by which Darwin formulated and modified his theory of natural selection
B. Propose a new interpretation of Darwin’s theory of evolution
C. Explain how other scientists of the time helped Darwin modify and perfect his theories
D. Defend Darwinian theory against the objections raised by Darwin’s contemporaries in the scientific community
E. Discuss some of the scientific controversy that Darwin sparked and describe his response to it

2 
 2. It can be inferred from the passage that the theory of blending inheritance would predict that the offspring of

A. Two strains of snapdragons, one with abnormal, radically symmetrical flowers and the other with normal, bilaterally symmetrical flowers, would always have normal, bilaterally symmetrical flowers
B. A white horse and a black horse would always be gray
C. A man with type A blood and a woman with type B blood would always have type A, type B, or type AB blood
D. A fly with large eyes and a fly with small eyes would always have one large eye and one small eye
E. Two pink-flowered plants would always be red or white

3 
 3. It can be inferred from the passage that “wild-type” ( Highlighted ) means

A. Nonmutant
B. Rare
C. Abnormal
D. Random
E. Favorable

4 
 4. Which of the following, if it could be demonstrated, would tend to support the Lamarckian concept that Darwin embraced?

A. Human beings evolved from now-extinct animals much like chimpanzees as a result of an erratic accumulation of changes in the gene pool through thousands of generations.
B. Some parental traits disappear in offspring and reappear in the following generation.
C. All species of organisms were immutably created in their present forms.
D. Rats who have had their trails cut off produce tailless offspring.
E. Those hereditary traits that make their owners more likely to grow up and reproduce become increasingly common in a population from one generation to the next.

5 
 5. The author’s attitude toward Jenkin and Kelvin can best be described as

A. Respectful
B. Contemptuous
C. Ambivalent
D. Denunciatory
E. Adulatory

6 
 6. According to the passage, Darwin modified his beliefs in order to

A. Bring them into line with the theory of particulate inheritance
B. Disprove Lord Kelvin’s view on the age of the earth
C. Meet the objections of Jenkin and Lamarck
D. Resolve theological conflicts about evolution
E. Dissociate himself from those who believed in “special creationism” (line 21)

7 
 7. The author sets off the word “rediscovered” ( Highlighted ) in quotation marks in order to

A. Emphasize that major scientific theories are rarely acknowledged or accepted when they are first promulgated
B. Indicate that the term is somewhat ironic, since Mendel’s work was virtually ignored when it was published
C. Rebuke the scientific community for deliberately suppressing Mendel’s work until long after his death
D. Underscore the similarity between Mendel’s theory of particulate inheritance and the theory of blending inheritance that was accepted during his lifetime
E. Suggest that a scientist of Darwin’s stature should have read Mendel’s work when it was first published and immediately recognized its importance

8 
 8. It can be inferred from the passage that if Mendel’s work had been recognized and accepted during Darwin’s lifetime, it would have had which of the following effect?

I. It would have refuted Jenkin’s objections to Darwin’s theories.
II. It would have supported Darwin’s theory that evolution proceeds by very slow steps over millions of years.
III. It would have clarified and supported Darwin’s theory of natural selection.

A. I only
B. III only
C. I and III only
D. II and III only
E. I, II, and III

9 
 9. All of the following can be reasonably inferred from the passage EXCEPT:

A. The idea that evolution occurs by means of natural selection was not widely accepted until the twentieth century.
B. Darwin’s theories were originally predicated on the assumption that the earth is more than 40 million years old.
C. Many of Darwin’s ideas about heredity were later shown to be incorrect.
D. Other scientists of Darwin’s time, including both Jenkin and Lamarck, believed in evolution.
E. Darwin was the only scientist of his day who believed in natural selection.

bM22 · Answer

5. The author’s attitude toward Jenkin and Kelvin can best be described as

A. Respectful 
B. Contemptuous
C. Ambivalent
D. Denunciatory
E. Adulatory

Explanation: The author discusses the theories of Jenkin and Kelvin, and how it lead Darwin to modify his theory, but how later their theories were found to be faulty. But the author's attitude is neither disrespectful or blaming nor praising. He is simply discussing the respective theories. Thus, A is the only apt choice.

6. According to the passage, Darwin modified his beliefs in order to

A. Bring them into line with the theory of particulate inheritance
B. Disprove Lord Kelvin’s view on the age of the earth
C. Meet the objections of Jenkin and Lamarck
D. Resolve theological conflicts about evolution
 E. Dissociate himself from those who believed in “special creationism” (line 21)

Explanation: can be inferred from the lines in the 4th para: "Since “special creationism” was an ideological target of his, Darwin found himself in a quandary. Although he did not abandon his theory, he admitted that natural selection played a much smaller part in evolution than he had previously claimed.", implying that Darwin modified his belief in order to avoid uncertainties and thus admitted that natural selection played a much smaller part in evolution than he had previously claimed.

9. All of the following can be reasonably inferred from the passage EXCEPT:

A. The idea that evolution occurs by means of natural selection was not widely accepted until the twentieth century.
B. Darwin’s theories were originally predicated on the assumption that the earth is more than 40 million years old.
C. Many of Darwin’s ideas about heredity were later shown to be incorrect.
D. Other scientists of Darwin’s time, including both Jenkin and Lamarck, believed in evolution.
 E. Darwin was the only scientist of his day who believed in natural selection.

Explanation: We cannot infer from the passage, if Darwin was the only scientist of his day who believed in natural selection, as there could be or could not be others. Others options can be easily inferred from the passage.

Hope This Helps.
Thanks.

elavendan1 · Answer

A. Outline the process by which Darwin formulated and modified his theory of natural selection
B. Propose a new interpretation of Darwin’s theory of evolution
C. Explain how other scientists of the time helped Darwin modify and perfect his theories
D. Defend Darwinian theory against the objections raised by Darwin’s contemporaries in the scientific community
E. Discuss some of the scientific controversy that Darwin sparked and describe his response to it

For Q1, I didn't get why option D was wrong. Option A and E encompasses all the major points, but leaves out the last para. In the last passage, the author clearly said the issues raised by contemporaries were nullified by the later scientific discoveries. I think A and E misses out this part.

Also, the passage starts with, 
 
Although much has been written about the theological conflicts with Darwinian theory, little is known of the powerful scientific objections that modified Darwin’s beliefs. 
Technically, Darwin did not 'spark' any controversy or no such controversy has been mentioned! It is true that the theories were debated upon and he, accordingly, modified the aspects. If option E has been the answer, then we may not need the concluding para, at all.

Can anyone explain why the option E is correct?

ryorda · Answer

Very nice passage with tricky questions!

Hi all, 
could anyone explain why :
1. Q1 is not A? it seems explain how Darwin modify his theory
2. Q6 is not D? he was trying to comply with other theories made by other scientists
3. Q8 , option II is wrong ? Mendel found that sun's age is infinite
4. Q9 is not A ? I thought Darwin's theory is accepted until 20th century

thanks in advance

bM22 · Answer

The passage does talk about how Darwin modified his theory, but it would be incomplete as we need to know what caused Darwin to modify his theory. From the passage, we can see that Darwin through his theories sparked certain contradicting theories by Jenkin and Lord Kelvin, and later he responded to the contradictions by modifying this theory. Thus, from this analysis we can see that E is a better suited answer.

D is incorrect and that can be inferred from the 1st 3 lines of the passage: "Although much has been written about the theological conflicts with Darwinian theory, little is known of the powerful scientific objections that modified Darwin’s beliefs."

Though II is correct, it is incorrect w.r.t the Question, as we cannot infer with certainty that the discovery that the sun runs on a nearly infinite amount of atomic fuel totally invalidated Kelvin’s argument, was made by Mendal.

A can be inferred from the last para: "The discovery that the sun runs on a nearly infinite amount of atomic fuel totally invalidated Kelvin’s argument, Mendel was “rediscovered” in the twentieth century........but could rapidly become prevalent.". Darwin's theory had to face a lot of scientific objections until 20th Century. It was not until Kelvin's arguments were invalidated and it was found that both the modifications by Darwin were incorrect.

Hope This Helps.
Thanks.

bM22 · Answer

Hi  elavendan1 ,

Author is not seen to defending anything here. He simply mentions the scientific objections by Jenkin and Kelvin and how Darwin modified his beliefs based on those and those retreats later turned out to be faulty.

Darwin sparked 2 major controversies:
1. conception of evolution as proceeding through the natural selection of those with slightly better characteristics that arose randomly, which was objected by Jenkin.
2. evolution proceed by slow steps in millions of years, and how could advanced forms recently evolved show such great differences,which was objected by Kelvin.

It was Darwin's beliefs that led to these objections and that in turn led Darwin to modify his beliefs, and those modifications later turned out to be faulty.

E is best suited as the primary purpose of the passage, as author discusses the objections that Darwin sparked and how he responded to those.

Primary purpose of any passage is about what the author wants to convey. Last para also contributes to the primary purpose as author concludes how Darwin's modifications were faulty, thus completing the discussion about the scientific controversy sparked by Darwin.

Hope This Helps.
Thanks.

soondoobu · Answer

In q6, I can see why answer choice E is the correct answer - but what makes answer choice D wrong? He was trying to resolve conflicts from Kelvin and made some modifications to his theory.

VeritasKarishma   MartyTargetTestPrep

KarishmaB · Answer

6. According to the passage, Darwin modified his beliefs in order to

B. Disprove Lord Kelvin’s view on the age of the earth

Incorrect.

The Kelvinists, basing their conclusion on the assumption that the sun was an incandescent liquid mass rapidly radiating heat, calculated that the age of the earth was between 20 and 40 million years.

Admitting that their calculations were correct and their premises rational, Darwin was forced to adjust this theory.

Darwin admitted to their calculations. He did not disprove Lord Kelvin's view.

D. Resolve theological conflicts about evolution

Incorrect. He did not adjust his theory to resolve theological conflicts (conflicts with those who believed in God and his creation of humans as special). He adjusted his theory due to scientific objections.

KarishmaB · Answer

2. It can be inferred from the passage that the theory of blending inheritance would predict that the offspring of

A. Two strains of snapdragons, one with abnormal, radically symmetrical flowers and the other with normal, bilaterally symmetrical flowers, would always have normal, bilaterally symmetrical flowers
B. A white horse and a black horse would always be gray
C. A man with type A blood and a woman with type B blood would always have type A, type B, or type AB blood
D. A fly with large eyes and a fly with small eyes would always have one large eye and one small eye
E. Two pink-flowered plants would always be red or white

"blending inheritance, which holds that forms intermediate between those of the parents result from mating."

So mating of a white horse and a black horse would result in a grey horse - intermediate between white and black.

Answer (B)

KarishmaB · Answer

7. The author sets off the word “rediscovered” (Highlighted) in quotation marks in order to

A. Emphasize that major scientific theories are rarely acknowledged or accepted when they are first promulgated
B. Indicate that the term is somewhat ironic, since Mendel’s work was virtually ignored when it was published
C. Rebuke the scientific community for deliberately suppressing Mendel’s work until long after his death
D. Underscore the similarity between Mendel’s theory of particulate inheritance and the theory of blending inheritance that was accepted during his lifetime
E. Suggest that a scientist of Darwin’s stature should have read Mendel’s work when it was first published and immediately recognized its importance

Relevant lines from the passage:
 During Darwin’s lifetime, the accepted theory of heredity was not Mendel’s theory of particulate inheritance, which, though published, was unrecognized, but the theory of ...
... The discovery that the sun runs on a nearly infinite amount of atomic fuel totally invalidated Kelvin’s argument, Mendel was “rediscovered” in the twentieth century, when it was pointed out that the particulate nature of inheritance meant that favorable mutation not only could persist, but could rapidly become prevalent.

The author tells us that Mendel's work was not recognised at that time but was later "discovered" when other discoveries were made.
Hence (B)

KarishmaB · Answer

8. It can be inferred from the passage that if Mendel’s work had been recognized and accepted during Darwin’s lifetime, it would have had which of the following effect?

I. It would have refuted Jenkin’s objections to Darwin’s theories.
II. It would have supported Darwin’s theory that evolution proceeds by very slow steps over millions of years.
III. It would have clarified and supported Darwin’s theory of natural selection.

A. I only
B. III only
C. I and III only
D. II and III only
E. I, II, and III

Relevant lines:

...Not particulate inheritance (genes passing traits)... but blending inheritance was accepted..., which holds that forms intermediate between those of the parents result from mating. Jenkin pointed out that if a rare and favorable mutation occurred, it would soon be blended out by repeated crossings from the wild-type form.

If particulate inheritance were accepted, Jenkin would not have this objection against Darwin's theory. (I) is correct.

Relevant lines:

Mendel was “rediscovered” in the twentieth century, when it was pointed out that the particulate nature of inheritance meant that favorable mutation not only could persist, but could rapidly become prevalent.

Particulate inheritance means that favourable mutation could rapidly become prevalent. 
Hence (II) is not correct and (III) is.

Answer (C)

Pranavsawant · Answer

Can someone explain question 3? How is wild type similar to non-mutant? What makes us think those forms don't mutate?

Sajjad1994 · Answer

Hello Pranavsawant

The term  "wild-type"  is used in the context of Jenkin's objection to Darwin's theory. Jenkin argued that if a rare and favorable mutation occurred, it would soon be  "blended out by repeated crossings from the wild-type form."  The  "wild-type"  form is contrasted with the  "rare and favorable mutation."  This implies the wild-type is the common, original, or standard form of the organism, as opposed to the mutated variant.

In genetics,  "wild-type"  refers to the typical, non-mutated form of a gene or organism that occurs naturally in a population. It is the baseline or  "normal"  form, while mutations are deviations from it. Thus,  "wild-type"  aligns with  "nonmutant"  because it represents the unaltered, original state before any mutations arise.

Pranavsawant · Answer

I agree that wild-type refers to the typical and normal form but to say that it is non-mutant is a bit of a stretch. How can you conclude that the normal variant doesn't mutate? The normal, typical corresponds more with random (randomness of a variable as in statistics). Opposite to rare and favorable with be unfavorable or normal mutation. But saying that it is non-mutant doesn't really make sense.

Also how genetics defines it is irrelevant as we can't use external knowledge to answer these questions.

Also how genetics defines it is irrelevant as we can't use external knowledge to answer these questions.

Sajjad1994 · Answer

Lines 8-10 from the passage:

"Jenkin pointed out that if a rare and favorable mutation occurred, it would soon be blended out by repeated crossings from the wild-type form."

The wild-type is being contrasted with a  "rare and favorable mutation."  The wild-type form is what the mutation would blend back into through repeated crossings. The wild-type is the original, non-mutated form that mutations would blend back into. Although i agree that wild-type could mutate (making "nonmutant" slightly imperfect), in this context it's clearly being contrasted with a new mutation, so it means the pre-existing, non-mutated form.

Although much has been written about the theological conflicts with

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

GMAT Reading Comprehension (RC) Questions

Although much has been written about the theological conflicts with

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia