SAT Critical Reading : Natural Science Passages

Study concepts, example questions & explanations for SAT Critical Reading

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Example Questions

Example Question #151 : Content Of Natural Science Passages

"Interpreting the Copernican Revolution" by Matthew Minerd (2014)

The expressions of one discipline can often alter the way that other subjects understand themselves. Among such cases are numbered the investigations of Nicolaus Copernicus. Copernicus is best known for his views concerning heliocentrism, a view which eventually obliterated many aspects of the ancient/medieval worldview, at least from the standpoint of physical science. It had always been the natural view of mankind that the earth stood at the center of the universe, a fixed point in reference to the rest of the visible bodies. The sun, stars, and planets all rotated around the earth.

With time, this viewpoint became one of the major reference points for modern life. It provided a provocative image that was used—and often abused—by many people for various purposes. For those who wished to weaken the control of religion on mankind, it was said that the heliocentric outlook proved man’s insignificance. In contrast with earlier geocentrism, heliocentrism was said to show that man is not the center of the universe. He is merely one small being in the midst of a large cosmos. However, others wished to use the “Copernican Revolution” in a very different manner. These thinkers wanted to show that there was another “recentering” that had to happen. Once upon a time, we talked about the world. Now, however, it was necessary to talk of man as the central reference point. Just as the solar system was “centered” on the sun, so too should the sciences be centered on the human person.

However, both of these approaches are fraught with problems. Those who wished to undermine the religious mindset rather misunderstood the former outlook on the solar system. The earlier geocentric mindset did not believe that the earth was the most important body in the heavens. Instead, many ancient and medieval thinkers believed that the highest “sphere” above the earth was the most important being in the physical universe. Likewise, the so-called “Copernican Revolution” in physics was different from the one applied to the human person. Copernicus’ revolution showed that the human point of view was not the center, whereas the later forms of “Copernican revolution” wished to show just the opposite.

Of course, there are many complexities in the history of such important changes in scientific outlook. Nevertheless, it is fascinating to see the wide-reaching effects of such discoveries, even when they have numerous, ambiguous effects.

What can we say, in general, about the interpretations that have been offered for the effects of Copernicus’ discoveries?

Possible Answers:

They have provided the grounds for a fruitful dialogue between religion and science.

They have unlocked a number of themes that were long hidden by the powers of religion and authoritarian regimes.

They have been abused for tyrannical purposes by many parties.

None of the other answers

They have been used more according to the disposition of their interpreters than in accord with the reality of the facts.

Correct answer:

They have been used more according to the disposition of their interpreters than in accord with the reality of the facts.

Explanation:

While the passage does catalogue two different worldviews that emerged from Copernicus' findings, it ultimately stresses the point that such outlooks are both limited because of their adherents' biases. Neither of them really reads the history or even the general images correctly. It seems that each one uses the findings as an occasion for strengthening his or her outlook on reality, whatever that might be.

Example Question #152 : Content Of Natural Science Passages

"Interpreting the Copernican Revolution" by Matthew Minerd (2014)

The expressions of one discipline can often alter the way that other subjects understand themselves. Among such cases are numbered the investigations of Nicolaus Copernicus. Copernicus is best known for his views concerning heliocentrism, a view which eventually obliterated many aspects of the ancient/medieval worldview, at least from the standpoint of physical science. It had always been the natural view of mankind that the earth stood at the center of the universe, a fixed point in reference to the rest of the visible bodies. The sun, stars, and planets all rotated around the earth.

With time, this viewpoint became one of the major reference points for modern life. It provided a provocative image that was used—and often abused—by many people for various purposes. For those who wished to weaken the control of religion on mankind, it was said that the heliocentric outlook proved man’s insignificance. In contrast with earlier geocentrism, heliocentrism was said to show that man is not the center of the universe. He is merely one small being in the midst of a large cosmos. However, others wished to use the “Copernican Revolution” in a very different manner. These thinkers wanted to show that there was another “recentering” that had to happen. Once upon a time, we talked about the world. Now, however, it was necessary to talk of man as the central reference point. Just as the solar system was “centered” on the sun, so too should the sciences be centered on the human person.

However, both of these approaches are fraught with problems. Those who wished to undermine the religious mindset rather misunderstood the former outlook on the solar system. The earlier geocentric mindset did not believe that the earth was the most important body in the heavens. Instead, many ancient and medieval thinkers believed that the highest “sphere” above the earth was the most important being in the physical universe. Likewise, the so-called “Copernican Revolution” in physics was different from the one applied to the human person. Copernicus’ revolution showed that the human point of view was not the center, whereas the later forms of “Copernican revolution” wished to show just the opposite.

Of course, there are many complexities in the history of such important changes in scientific outlook. Nevertheless, it is fascinating to see the wide-reaching effects of such discoveries, even when they have numerous, ambiguous effects.

Why is the "Copernican revolution" of the human sciences contrary to the literal sense of Copernicus' findings?

Possible Answers:

Copernicus' findings were scientific in contrast to nebulous humanistic aims.

Copernicus' findings were focused on a new external "center," drawing attention away from the immediate center experienced in day-to-day life.

Copernicus' findings aim only at disproving a former worldview, not finding new data around a new center of experience.

Copernicus' scientific aims immediately prove the fact that the human person is merely a speck on a rock in a large universe.

None of the other answers

Correct answer:

Copernicus' findings were focused on a new external "center," drawing attention away from the immediate center experienced in day-to-day life.

Explanation:

The key sentence for this question is: "Copernicus’ revolution showed that the human point of view was not the center, whereas the later forms of 'Copernican revolution' wished to show just the opposite." To start looking at the sun as the center requires us to "look outward" in a new way, not paying attention to our particular earth-bound viewpoint. However, the "Copernican revolution" centered on humanity does just the opposite. It turns the gaze "inward," quite different from the literal sense of Copernicus' findings.

Example Question #231 : Natural Science Passages

"The Place of Lesion Studies in Neuroscience" by Samantha Winter (2013)

It’s easy to forget that the study of neuroscience originated from non-normalized, non-statistically appraised methods like lesion studies. It’s equally easy, with the advent of sophisticated technology, to render such a method obsolete. A small group of neuroscientists today make a case for the reinstitution of lesion studies—the study of abnormal brains with damaged regions in order to better understand the brain—into the twenty-first-century cognitive neuroscience realm. Their suggestion is bold, but their argument is justified.

Cognitive neuroscientists advocate for the use of convergent methods. Many of them argue that with the limitations of our existing techniques, convergent evidence is imperative for sound research. If this is the case, why ignore a method that has potential for implying causality in a domain dominated by correlational research? Rather than advocating for a single method, neuroscientists should take their own advice and use convergent techniques. Sound research should combine a variety of techniques to examine both causal relationships and overcome the individual shortcomings of each method through the use of many.

Lesion studies are also significantly more beneficial now than they were in earlier times. Neuroimaging methods have enhanced our understanding of what contributes to the brain problems most often encountered, and more refined experiments have been developed to confirm the findings from the more unreliable lesion studies. This transformation allows lesion studies to be included alongside the other systems as a mechanism for understanding the human brain.

The primary goal of this passage is __________.

Possible Answers:

To argue against the use of lesion studies

To convince readers that lesion studies are more effective than all other neuroscience studies and to present the opinion that lesion studies are valuable and should be used in combination with other techniques

To provide the reader with a thorough understanding of the terms “correlational” and “causational”

To discuss the specific limitations of all neuroscience methods

To present the opinion that lesion studies are valuable and should be used in combination with other techniques

Correct answer:

To present the opinion that lesion studies are valuable and should be used in combination with other techniques

Explanation:

While "to convince readers that lesion studies are more effective than all other neuroscience studies and to present the opinion that lesion studies are valuable and should be used in combination with other techniques" may seem correct at first, on close inspection, the passage indicates that lesion studies should be used in convergence with other methods and does not directly discuss the effectiveness of lesion studies in comparison with other methods. "To discuss the specific limitations of all neuroscience methods" is incorrect because no specific limitations are cited. "To provide the reader with a thorough understanding of the terms 'correlational' and 'causational'" may seem like a viable option because the passage does address these concepts, but they are not the core tenet of the passage. "To present the opinion that lesion studies are valuable and should be used in combination with other techniques" is correct because the passage repeatedly comments on the use of convergent techniques, including lesion studies, to better understand the brain.

 

Example Question #1 : Ideas In Science Passages

Adapted from Volume Four of The Natural History of Animals: The Animal Life of the World in Its Various Aspects and Relations by James Richard Ainsworth Davis (1903)

The examples of protective resemblance so far quoted are mostly permanent adaptations to one particular sort of surrounding. There are, however, numerous animals which possess the power of adjusting their color more or less rapidly so as to harmonize with a changing environment.

Some of the best known of these cases are found among those mammals and birds that inhabit countries more or less covered with snow during a part of the year. A good instance is afforded by the Irish or variable hare, which is chiefly found in Ireland and Scotland. In summer, this looks very much like an ordinary hare, though rather grayer in tint and smaller in size, but in winter it becomes white with the exception of the black tips to the ears. Investigations that have been made on the closely allied American hare seem to show that the phenomenon is due to the growth of new hairs of white hue. 

The common stoat is subject to similar color change in the northern parts of its range. In summer it is of a bright reddish brown color with the exception of the under parts, which are yellowish white, and the end of the tail, which is black. But in winter, the entire coat, save only the tip of the tail, becomes white, and in that condition the animal is known as an ermine. A similar example is afforded by the weasel. The seasonal change in the vegetarian Irish hare is purely of protective character, but in such an actively carnivorous creature as a stoat or weasel, it is aggressive as well, rendering the animal inconspicuous to its prey.

Which of the following best expresses the main idea of the passage?

Possible Answers:

Increased defense is the only reason for an animal to change its fur color.

Certain animals change their fur color to be better predators or better at hiding.

Animals like the stoat, the weasel, and the Irish hare are better adapted to changing environments than to unchanging ones.

All animals that live in a changing environment change color.

The Scottish hare changes its fur color.

Correct answer:

Certain animals change their fur color to be better predators or better at hiding.

Explanation:

When answering questions about the main idea of a passage, it’s important to pick out an answer choice to which each paragraph relates, but one that isn’t too broad. Some of the answer choices to this question are too specific: “The Scottish hare changes its fur color” is, and we can tell because the first paragraph doesn’t say anything about the Scottish hare, and the third paragraph only mentions it in its last line. “Increased defense is the only reason for an animal to change its fur color” should get your attention due to its use of the word “only”—did we hear anything in the passage about color-changing adaptations being used “only” for defense? No, we heard the opposite, in the passage’s last line: “The seasonal change in the vegetarian Irish hare is purely of protective character, but in such an actively carnivorous creature as a stoat or weasel, it is aggressive as well, rendering the animal inconspicuous to its prey.” The language may be a bit dense here, but what the passage is saying is that the hare uses its color-changing adaptation for defense, but stoats and weasels use it for being better predators and sneaking up on their prey—definitely not a defensive use. Similarly, “All animals that live in a changing environment change color” is making a strong statement due to its use of the word “all.” The passage gives us a few examples of animals that change that live in a changing environment and change their color, but this isn’t enough for us to assume that all animals that live in changing environments act this way. 

Example Question #91 : Understanding The Content Of Natural Science Passages

Adapted from Volume Four of The Natural History of Animals: The Animal Life of the World in Its Various Aspects and Relations by James Richard Ainsworth Davis (1903)

The examples of protective resemblance so far quoted are mostly permanent adaptations to one particular sort of surrounding. There are, however, numerous animals which possess the power of adjusting their color more or less rapidly so as to harmonize with a changing environment.

Some of the best known of these cases are found among those mammals and birds that inhabit countries more or less covered with snow during a part of the year. A good instance is afforded by the Irish or variable hare, which is chiefly found in Ireland and Scotland. In summer, this looks very much like an ordinary hare, though rather grayer in tint and smaller in size, but in winter it becomes white with the exception of the black tips to the ears. Investigations that have been made on the closely allied American hare seem to show that the phenomenon is due to the growth of new hairs of white hue. 

The common stoat is subject to similar color change in the northern parts of its range. In summer it is of a bright reddish brown color with the exception of the under parts, which are yellowish white, and the end of the tail, which is black. But in winter, the entire coat, save only the tip of the tail, becomes white, and in that condition the animal is known as an ermine. A similar example is afforded by the weasel. The seasonal change in the vegetarian Irish hare is purely of protective character, but in such an actively carnivorous creature as a stoat or weasel, it is aggressive as well, rendering the animal inconspicuous to its prey.

The purpose of the passage’s third paragraph is __________.

Possible Answers:

to provide an example of an animal that goes by two different names depending on its appearance

to describe why stoats and weasels have a hard time hunting Irish hares in winter

to describe an animal that has adapted to an unchanging environment

to provide an example color-change in animals that is both aggressive and defensive

to describe the appearance of a stoat in summer

Correct answer:

to provide an example color-change in animals that is both aggressive and defensive

Explanation:

When answering questions about a paragraph’s purpose, it’s helpful to consider how it relates to the rest of the passage as a whole, and to consider what each of the other paragraphs do in the context of the passage. For instance, in this passage, the first paragraph transitions from discussing animal adaptations in unchanging environments to discussing animal adaptations in changing environments. The second paragraph talks about Irish hares as an example of animals that change their fur color. So, what is the point of the third paragraph? While it does “provide an example of an animal that goes by two different names depending on its appearance” and “describe the appearance of a stoat in summer,” neither of these is its main point; these are details, and neither seems to relate that much to the points of the previous paragraphs. Stoats and weasels are not described as specifically hunting Irish hares, and the passage describes how their changing fur color helps them be better hunters, not why they have such a hard time hunting, so “to describe why stoats and weasels have a hard time hunting Irish hares in winter” cannot be the correct answer either. The point of the paragraph cannot be “to describe an animal that has adapted to an unchanging environment” either, because it describes stoats and weasels, animals that adapt to changing environments. This leaves us with one answer, the correct one: “to provide an example color-change in animals that is both aggressive and defensive.” The examples of stoats and weasels both fall into this category, which is contrasted with the purely defensive function of color-change in hares in the passage’s last sentence.

Example Question #1 : Understanding The Content Of Natural Science Passages

Adapted from Essays on Early Ornithology and Kindred Subjects by James R. McClymont (1920)

The voyagers named it the Angra de Santa Elena, and it may have been the bay which is now known as St. Helen’s Bay. But it is worthy of note that the G. de Sta. Ellena of the Cantino Chart is laid down in a position which corresponds rather with that of Table Bay than with that of St. Helen’s Bay.

The Portuguese came into contact with the inhabitants of the country adjacent to the anchorage. These people had tawny complexions, and carried wooden spears tipped with horn—assagais of a kind—and bows and arrows. They also used foxes’ tails attached to short wooden handles. We are not informed for what purposes the foxes’ tails were used. Were they used to brush flies away, or were they insignia of authority? The food of the natives was the flesh of whales, seals, and antelopes (gazellas), and the roots of certain plants. Crayfish or ‘Cape lobsters’ abounded near the anchorage.

The author of the roteiro affirms that the birds of the country resembled the birds in Portugal, and that amongst them were cormorants, larks, turtle-doves, and gulls. The gulls are called "guayvotas," but "guayvotas" is probably another instance of the eccentric orthography of the author and equivalent to "gaivotas."

In December the squadron reached the Angra de São Bràs, which was either Mossel Bay or another bay in close proximity to Mossel Bay. Here penguins and seals were in great abundance. The author of the roteiro calls the penguins "sotelycairos," which is more correctly written "sotilicarios" by subsequent writers. The word is probably related to the Spanish "sotil" and the Latin "subtilis," and may contain an allusion to the supposed cunning of the penguins, which disappear by diving when an enemy approaches.

The sotilicarios, says the chronicler, could not fly because there were no quill-feathers in their wings; in size they were as large as drakes, and their cry resembled the braying of an ass. Castanheda, Goes, and Osorio also mention the sotilicario in their accounts of the first voyage of Vasco da Gama, and compare its flipper to the wing of a bat—a not wholly inept comparison, for the under-surface of the wings of penguins is wholly devoid of feathery covering. Manuel de Mesquita Perestrello, who visited the south coast of Africa in 1575, also describes the Cape penguin. From a manuscript of his Roteiro in the Oporto Library, one learns that the flippers of the sotilicario were covered with minute feathers, as indeed they are on the upper surface and that they dived after fish, upon which they fed, and on which they fed their young, which were hatched in nests constructed of fishbones. There is nothing to cavil at in these statements, unless it be that which asserts that the nests were constructed of fishbones, for this is not in accordance with the observations of contemporary naturalists, who tell us that the nests of the Cape Penguin (Spheniscus demersus) are constructed of stones, shells, and debris. It is, therefore, probable that the fishbones which Perestrello saw were the remains of repasts of seals.

Seals, says the roteiro, were in great number at the Angra de São Bràs. On one occasion the number was counted and was found to be three thousand. Some were as large as bears and their roaring was as the roaring of lions. Others, which were very small, bleated like kids. These differences in size and in voice may be explained by differences in the age and in the sex of the seals, for seals of different species do not usually resort to the same locality. The seal which formerly frequented the south coast of Africa—for it is, I believe, no longer a denizen of that region—was that which is known to naturalists as Arctocephalus delalandii, and, as adult males sometimes attain eight and a half feet in length, it may well be described as of the size of a bear. Cubs from six to eight months of age measure about two feet and a half in length. The Portuguese caught anchovies in the bay, which they salted to serve as provisions on the voyage. They anchored a second time in the Angra de São Bràs in March, 1499, on their homeward voyage.

Yet one more allusion to the penguins and seals of the Angra de São Bràs is of sufficient historical interest to be mentioned. The first Dutch expedition to Bantam weighed anchor on the 2nd of April, 1595, and on the 4th of August of the same year the vessels anchored in a harbor called "Ague Sambras," in eight or nine fathoms of water, on a sandy bottom. So many of the sailors were sick with scurvy—"thirty or thirty-three," said the narrator, "in one ship"—that it was necessary to find fresh fruit for them. "In this bay," runs the English translation of the narrative, "lieth a small Island wherein are many birds called Pyncuins and sea Wolves that are taken with men’s hands." In the original Dutch narrative by Willem Lodewyckszoon, published in Amsterdam in 1597, the name of the birds appears as "Pinguijns."

What is the main idea of the first paragraph?

Possible Answers:

The shoreline was meticulously mapped.

The voyagers showed no interest in the animals they encountered.

The men who named the bay were deeply religious.

The sailors did not know where they were going.

There are discrepancies between the names and the places mapped. 

Correct answer:

There are discrepancies between the names and the places mapped. 

Explanation:

The purpose of this paragraph is to illustrate the location the text it is concerned with. It says that it is important to note that what was called “Angra de Santa Elena” by the voyagers does not correspond fully to “St. Helen’s Bay.” Instead it is closer to “Table bay” on a certain map or “chart."

Example Question #2 : Understanding The Content Of Natural Science Passages

Adapted from Essays on Early Ornithology and Kindred Subjects by James R. McClymont (1920)

The voyagers named it the Angra de Santa Elena, and it may have been the bay which is now known as St. Helen’s Bay. But it is worthy of note that the G. de Sta. Ellena of the Cantino Chart is laid down in a position which corresponds rather with that of Table Bay than with that of St. Helen’s Bay.

The Portuguese came into contact with the inhabitants of the country adjacent to the anchorage. These people had tawny complexions, and carried wooden spears tipped with horn—assagais of a kind—and bows and arrows. They also used foxes’ tails attached to short wooden handles. We are not informed for what purposes the foxes’ tails were used. Were they used to brush flies away, or were they insignia of authority? The food of the natives was the flesh of whales, seals, and antelopes (gazellas), and the roots of certain plants. Crayfish or ‘Cape lobsters’ abounded near the anchorage.

The author of the roteiro affirms that the birds of the country resembled the birds in Portugal, and that amongst them were cormorants, larks, turtle-doves, and gulls. The gulls are called "guayvotas," but "guayvotas" is probably another instance of the eccentric orthography of the author and equivalent to "gaivotas."

In December the squadron reached the Angra de São Bràs, which was either Mossel Bay or another bay in close proximity to Mossel Bay. Here penguins and seals were in great abundance. The author of the roteiro calls the penguins "sotelycairos," which is more correctly written "sotilicarios" by subsequent writers. The word is probably related to the Spanish "sotil" and the Latin "subtilis," and may contain an allusion to the supposed cunning of the penguins, which disappear by diving when an enemy approaches.

The sotilicarios, says the chronicler, could not fly because there were no quill-feathers in their wings; in size they were as large as drakes, and their cry resembled the braying of an ass. Castanheda, Goes, and Osorio also mention the sotilicario in their accounts of the first voyage of Vasco da Gama, and compare its flipper to the wing of a bat—a not wholly inept comparison, for the under-surface of the wings of penguins is wholly devoid of feathery covering. Manuel de Mesquita Perestrello, who visited the south coast of Africa in 1575, also describes the Cape penguin. From a manuscript of his Roteiro in the Oporto Library, one learns that the flippers of the sotilicario were covered with minute feathers, as indeed they are on the upper surface and that they dived after fish, upon which they fed, and on which they fed their young, which were hatched in nests constructed of fishbones. There is nothing to cavil at in these statements, unless it be that which asserts that the nests were constructed of fishbones, for this is not in accordance with the observations of contemporary naturalists, who tell us that the nests of the Cape Penguin (Spheniscus demersus) are constructed of stones, shells, and debris. It is, therefore, probable that the fishbones which Perestrello saw were the remains of repasts of seals.

Seals, says the roteiro, were in great number at the Angra de São Bràs. On one occasion the number was counted and was found to be three thousand. Some were as large as bears and their roaring was as the roaring of lions. Others, which were very small, bleated like kids. These differences in size and in voice may be explained by differences in the age and in the sex of the seals, for seals of different species do not usually resort to the same locality. The seal which formerly frequented the south coast of Africa—for it is, I believe, no longer a denizen of that region—was that which is known to naturalists as Arctocephalus delalandii, and, as adult males sometimes attain eight and a half feet in length, it may well be described as of the size of a bear. Cubs from six to eight months of age measure about two feet and a half in length. The Portuguese caught anchovies in the bay, which they salted to serve as provisions on the voyage. They anchored a second time in the Angra de São Bràs in March, 1499, on their homeward voyage.

Yet one more allusion to the penguins and seals of the Angra de São Bràs is of sufficient historical interest to be mentioned. The first Dutch expedition to Bantam weighed anchor on the 2nd of April, 1595, and on the 4th of August of the same year the vessels anchored in a harbor called "Ague Sambras," in eight or nine fathoms of water, on a sandy bottom. So many of the sailors were sick with scurvy—"thirty or thirty-three," said the narrator, "in one ship"—that it was necessary to find fresh fruit for them. "In this bay," runs the English translation of the narrative, "lieth a small Island wherein are many birds called Pyncuins and sea Wolves that are taken with men’s hands." In the original Dutch narrative by Willem Lodewyckszoon, published in Amsterdam in 1597, the name of the birds appears as "Pinguijns."

One of the main points made in the last paragraph is __________.

Possible Answers:

The seals and penguins seen had flippers like men's hands.

The expedition had to stop on the coast due to numerous cases of malnutrition aboard. 

The English translation of the account is incomplete.

The Dutch narrative of the expedition was printed within a year of the events.

The expedition stayed anchored in the bay for four months.

Correct answer:

The expedition had to stop on the coast due to numerous cases of malnutrition aboard. 

Explanation:

The expedition had to stop at least once because around thirty-three of the sailors had "scurvy," which is a disease resulting from a deficiency of vitamin C. This was usually prevalent on ships, where sailors' diet were poor that they developed the disease due to malnutrition.

Example Question #161 : Content Of Natural Science Passages

Adapted from "Taking a Second Look: An Analysis of Genetic Markers in Species Relatedness" by Joseph Ritchie (2014)

Phylogenetics is the study of genetic composition in various species and is used by evolutionary biologists to investigate similarities in the molecular sequences of proteins in varying organisms. The amino acid sequences that build proteins are used to construct mathmatical matrices that aid in determining evolutionary ties through the investigation of percentage similarities. The study of these matrices helps to expose evolutionary relationships between species that may not have the same overt characteristics.

Species adapt and evolve based on the pressures that exist in their environment. Climate, food source, and habitat availability are only a few factors that act on species adaptation. These stressors can alter the physical characteristics of organisms. This divergence in evolution has made it difficult to determine the interrelatedness of organisms by analyzing their physical characteristics alone.

For instance, looking only at physical characteristics, the ghost bat resembles a pigeon more than a spider monkey; however, phylogenetics has found that the amino acid sequences that construct the beta hemoglobin molecules of bats are twenty percent more similar to those of mammalian primates than those of birds. This helps reject the assumption that common physical characteristics between species are all that is needed to determine relatedness. 

The differences produced by divergent evolution observed in the forest-dwelling, arboreal spider monkey and the nocturnal, airborne ghost bat can be reconciled through homology. Homologous characteristics are anatomical traits that are similar in two or more different species. For instance, the bone structure of a spider monkey’s wrist and fingers greatly resembles that of a bat’s wing or even a whale’s fin. These similarities are reinforced by phylogenetic evidence that supports the idea that physically dissimilar species can be evolutionarily related through anatomical and genetic similarities.

The central idea of this passage is best described by which of the following statements?

Possible Answers:

Genetic analysis is the only method of studying evolutionary ties and species relatedness.

Phylogenetics is a relatively new area of study and has yet to yield supported conclusions on evolutionary histories.

Understanding divergent evolution is necessary for understanding species relatedness.

Despite differences in physical appearance, genetic similarities can aid in determining species relatedness and evolutionary histories.

Correct answer:

Despite differences in physical appearance, genetic similarities can aid in determining species relatedness and evolutionary histories.

Explanation:

This is the correct answer because it is the only statement that is supported by the passage. The passage introduces the field of phylogenetics and the need to explore evolution beyond simple examination of physical characteristics. It does not state which field of study is better or correct. It simply states that they compliment the same cause: the study of relatedness. The other choices are unsupported opinions. The answer choice about divergent evolution is incorrect because while the passage's fourth paragraph is about divergent evolution, the entire passage encompasses many more topics.

Example Question #1 : Drawing Generalizations About Natural Science Passages

"Darwinism's Effect on Science" by Matthew Minerd (2014)

For much of the history of human thought, the sciences have studied subjects that seemed to be eternal and unchanging. Even the basic laws of the Nile’s flooding were investigated in the hopes of finding never-altering laws. Similarly, the scientific investigations of the ancient Near East and Greece into the regular laws of the stars ultimately looked for constant patterns. This overall pattern of scientific reasoning has left deep marks on the minds of almost all thinkers and found its apotheosis in modern physics. From the time of the early renaissance to the nineteenth century, physics represented the ultimate expression of scientific investigation for almost all thinkers. Its static laws appeared to be the unchanging principles of all motion and life on earth. By the nineteenth century, it had appeared that only a few details had to be “cleared up” before all science was basically known.

In many ways, this situation changed dramatically with the arrival of Darwinism. It would change even more dramatically in early twentieth-century physics as well. Darwin’s theories of evolution challenged many aspects of the “static” worldview. Even those who did not believe that a divine being created an unchanging world were shaken by the new vistas opened up to science by his studies. It had been a long-accepted inheritance of Western culture to believe that the species of living organisms were unchanging in nature. Though there might be many different kinds of creatures, the kinds themselves were not believed to change. The thesis of a universal morphing of types shattered this cosmology, replacing the old world-view with a totally new one. Among the things that had to change in light of Darwin’s work was the very view of science held by most people.

Which of the following provides an example of the main idea asserted in the first paragraph?

Possible Answers:

The interest in science only arises once agriculture reaches a certain point of fixity.

The Pythagorean theorem is based upon the constant relationship of the sides of a right triangle to its hypotenuse.

None of the other answers

Religion constantly wanes with the rise of science.

The fluctuation of coloration within a species is rather minimal.

Correct answer:

The Pythagorean theorem is based upon the constant relationship of the sides of a right triangle to its hypotenuse.

Explanation:

The first paragraph discusses the role of necessary connections and unvarying rules in scientific thinking, particularly the type of thinking that has played a prominent role in Western thought for many centuries. The example of the Pythagorean theorem is a good example of this.  Even if you do not know this mathematical equation, you can tell that this is the correct answer by the words "constant relationship."

Example Question #1 : Comparing And Contrasting Ideas In Natural Science Passages

"Cacti" by Ami Dave (2013)

Cacti are plants suited to the desert, and we must always keep this factor in mind when growing ornamental cacti in our gardens, for it helps us provide cacti with conditions that allow them to survive and thrive. For example, a cactus should never be watered over its body, as it will start to rot. This is because it is covered with a waxy coating which prevents water loss through evaporation. When one waters the cactus over its body, the waxy coating is washed away and the plant begins to rot. The amount of water that one must supply to the cactus is very much dependent upon the season and upon the climate of the place. During the summer season one should water cacti every four days, whereas in the rainy season, once every fifteen days is quite enough.

Cacti need a minimum of two and a half hours of sunlight per day; however, they should not be kept in the sun all day because they may wrinkle when exposed to too much bright sunlight. Unlike other plants, cacti produce carbon dioxide during the day and oxygen during the night, so they are ideal plants to be kept in bedrooms to freshen up the air at night.

If a cactus is to thrive and prosper, the size of the pot in which it is grown needs to be monitored carefully. The pot should always be a little smaller than the plant itself because it is only when the plant has to struggle to survive that it will thrive. If the pot is too spacious and the plant does not need to struggle, chances are that the cactus will die. Similarly, if a cactus shows no signs of growth, stop watering it. Watering should be resumed only when the plant begins to grow again.

The substrata of a cactus pot is ideally composed of pieces of broken bricks at the bottom, followed by a layer of charcoal above the bricks, and then coarse sand and pebbles above the charcoal. Leaf mould is the best manure.

Grafting cacti is very simple. A very small piece of the cactus plant should be stuck with tape to the plant that needs grafting. The smaller the piece, the easier it is to graft. To reproduce cacti, one has to simply cut off a piece of the cactus, allow it to dry for a few days, and then place it over the cacti substrate. It will automatically develop roots.

It is very easy to differentiate between cacti and other plants that look like cacti. All cacti have fine hair at the base of each thorn. The so-called “thorns” are in fact highly modified leaves which prevent loss of water through transpiration. If one ever gets pricked by cacti thorns, one should take tape, place it over the area where the thorns have penetrated the skin, and then peel it off. All of the thorns will get stuck to the tape and will be removed.

The development of a new cactus from a graft is similar to what other biological phenomenon?

Possible Answers:

An unsuccessful kidney transplant

The birth of a genetically unique organism from an egg

A lizard that regrows its tail

A nematode worm that develops into two separate organisms when cut in half

A cut that successfully heals

Correct answer:

A nematode worm that develops into two separate organisms when cut in half

Explanation:

The passage discusses how grafting is a relatively simple procedure, and all that one must do is cut off a piece of the cactus and place it in an environment that supports its growth: the new cactus will develop roots. This is most similar to when a worm develops into a new organism when part of it is cut off. A lizard regrowing its tail is not similar to a graft, since the original organism simply regains the part that it lost. In the same vein, a cut that heals also involves an organism healing itself, not splitting apart to form a new organism. Birth from an egg or a failed organ transplant are not similar to the effects of a cactus graft.

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