Making Inferences in Natural Science Passages - GMAT Verbal
Card 1 of 60
Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
What can we infer from the underlined sentence, “Many \[hummingbirds\] in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig"?
Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
What can we infer from the underlined sentence, “Many \[hummingbirds\] in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig"?
Tap to reveal answer
What does the underlined sentence tell us? It refers to “Many” hummingbirds, not “all hummingbirds,” so we can’t infer that what it says holds true for all hummingbirds. This allows us to eliminate the answer choices that begin with “all hummingbirds,” leaving us with “Gnats are rarely found near bodies of water,” “Some hummingbirds live in the desert,” and “Some hummingbirds live near a body of water.” Regarding gnats, the sentence doesn’t suggest that they are rarely found near bodies of water, since it mentions hummingbirds “may be seen catching gnats and other small insects just like fly-catchers” and implies that they do this by “sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig.” We’re down to two answer choices: whether some hummingbirds live in the desert or near a body of water. The sentence doesn’t mention anything about deserts; on the contrary, it tells us that “many” hummingbirds catch gnats. The way that these hummingbirds do this begins with them “sitting on a dead twig over water.” So, we are told that many hummingbirds catch gnats and that in catching gnats, they sit over water. From this, we can infer that many hummingbirds live near bodies of water.
What does the underlined sentence tell us? It refers to “Many” hummingbirds, not “all hummingbirds,” so we can’t infer that what it says holds true for all hummingbirds. This allows us to eliminate the answer choices that begin with “all hummingbirds,” leaving us with “Gnats are rarely found near bodies of water,” “Some hummingbirds live in the desert,” and “Some hummingbirds live near a body of water.” Regarding gnats, the sentence doesn’t suggest that they are rarely found near bodies of water, since it mentions hummingbirds “may be seen catching gnats and other small insects just like fly-catchers” and implies that they do this by “sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig.” We’re down to two answer choices: whether some hummingbirds live in the desert or near a body of water. The sentence doesn’t mention anything about deserts; on the contrary, it tells us that “many” hummingbirds catch gnats. The way that these hummingbirds do this begins with them “sitting on a dead twig over water.” So, we are told that many hummingbirds catch gnats and that in catching gnats, they sit over water. From this, we can infer that many hummingbirds live near bodies of water.
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"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.
What could we expect the author to discuss in a paragraph following the last paragraph of this passage?
"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.
What could we expect the author to discuss in a paragraph following the last paragraph of this passage?
Tap to reveal answer
At the beginning of the second paragraph, the passage states, "It would change even more dramatically in early twentieth-century physics as well." In general, this passage is about the general transition from one scientific outlook to another. The details of Darwinism (or of the publication of textbooks as well) is not the main concern. Likely, the author would continue his or her discussion by returning to the theme of twentieth-century physics as well.
At the beginning of the second paragraph, the passage states, "It would change even more dramatically in early twentieth-century physics as well." In general, this passage is about the general transition from one scientific outlook to another. The details of Darwinism (or of the publication of textbooks as well) is not the main concern. Likely, the author would continue his or her discussion by returning to the theme of twentieth-century physics as well.
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Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in 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)
Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort.
Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.
Which of the following can we infer based on the passage?
Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in 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)
Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort.
Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.
Which of the following can we infer based on the passage?
Tap to reveal answer
This may seem like a tricky question, but let’s consider each of the answer choices individually:
“If sailors had visited Mauritius sooner, dodos might still be alive today.”: The passage doesn’t support this assertion at all. Since the arrival of sailors on New Zealand is identified as the cause of the dodo’s extinction, it doesn’t make sense that the dodo would have survived if the sailors would have arrived earlier; it would probably have gone extinct sooner, based on the passage’s logic.
“Ostriches would likely be as effective at running away from predators in tall grass as in open country.”: The passage specific disproves this when it says of ostriches and their running abilities, “For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies.” This suggests that ostriches are better adapted to surviving in open country than in areas covered by tall grass.
“The land-rail and corn-crake are not well adapted to running through tall grass.”: The passage disproves this answer choice when it describes the ability of rails to run through tall grass: “This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants.” After this sentence, the author mentions land-rails and corn-crakes’ abilities to evade hunters, so we can assume that these birds are well adapted to running through tall grass.
“Lizards were a predator of dodos.”: This can’t be true, because the passage tells us that “The dodo . . . was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards.” Given that when animals that preyed on the dodo were introduced to Mauritius, the dodo went extinct, we can assume that since the lizards and dodos coexisted before this point, the lizards did not prey on the dodos. If this were true, the dodos would likely have learned to run or fly away, which they did not.
This brings us to the remaining answer choice, the correct one: “If predatory ground-animals had lived on Mauritius, the dodo would have probably evolved to fly or run.” The author attributes the dodo’s extinction to the fact that it did not have to adapt and defend itself from any predators before humans introduced new species on Mauritius. From this, we can infer that if those species had been present, the dodo would have learned to fly, or, like the ostrich and the rail, would have learned to run to defend itself.
This may seem like a tricky question, but let’s consider each of the answer choices individually:
“If sailors had visited Mauritius sooner, dodos might still be alive today.”: The passage doesn’t support this assertion at all. Since the arrival of sailors on New Zealand is identified as the cause of the dodo’s extinction, it doesn’t make sense that the dodo would have survived if the sailors would have arrived earlier; it would probably have gone extinct sooner, based on the passage’s logic.
“Ostriches would likely be as effective at running away from predators in tall grass as in open country.”: The passage specific disproves this when it says of ostriches and their running abilities, “For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies.” This suggests that ostriches are better adapted to surviving in open country than in areas covered by tall grass.
“The land-rail and corn-crake are not well adapted to running through tall grass.”: The passage disproves this answer choice when it describes the ability of rails to run through tall grass: “This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants.” After this sentence, the author mentions land-rails and corn-crakes’ abilities to evade hunters, so we can assume that these birds are well adapted to running through tall grass.
“Lizards were a predator of dodos.”: This can’t be true, because the passage tells us that “The dodo . . . was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards.” Given that when animals that preyed on the dodo were introduced to Mauritius, the dodo went extinct, we can assume that since the lizards and dodos coexisted before this point, the lizards did not prey on the dodos. If this were true, the dodos would likely have learned to run or fly away, which they did not.
This brings us to the remaining answer choice, the correct one: “If predatory ground-animals had lived on Mauritius, the dodo would have probably evolved to fly or run.” The author attributes the dodo’s extinction to the fact that it did not have to adapt and defend itself from any predators before humans introduced new species on Mauritius. From this, we can infer that if those species had been present, the dodo would have learned to fly, or, like the ostrich and the rail, would have learned to run to defend itself.
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Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in 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)
Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort.
Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.
According to the passage, which of the following dates could have been the year in which the dodo went extinct?
Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in 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)
Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort.
Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.
According to the passage, which of the following dates could have been the year in which the dodo went extinct?
Tap to reveal answer
The only date discussed in the passage appears in the second paragraph, when the author refers to “the extinction of this helpless bird in less than a century after its first discovery in 1598.” As this is referring to the extinction of the dodo, it means that the dodo had to have gone extinct some time before 1698. The only answer choice that is a date before 1698 is 1654, so “1654” is the correct answer.
The only date discussed in the passage appears in the second paragraph, when the author refers to “the extinction of this helpless bird in less than a century after its first discovery in 1598.” As this is referring to the extinction of the dodo, it means that the dodo had to have gone extinct some time before 1698. The only answer choice that is a date before 1698 is 1654, so “1654” is the correct answer.
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Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
Based on what is said in the passage, the author most likely believes that .
Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
Based on what is said in the passage, the author most likely believes that .
Tap to reveal answer
This is a tricky question because in the passage, the author never directly states his opinion about what hummingbirds eat; readers have to infer it based on the evidence he presents. The author begins the passage by stating that while old scientists used to think hummingbirds ate only flower nectar, modern writers think that they eat “largely, and in some cases wholly,” on insects. He then presents evidence suggesting that hummingbirds eat insects, and in discussing the contents of hummingbirds’ stomachs, says that scientists sometimes find both insects and honey. For the rest of the paragraph, he provides evidence suggesting that hummingbirds eat insects.
What can we infer from this? Well, we can tell that it’s not likely that the author thinks hummingbirds eat only flower nectar, because he provides evidence supporting the idea that they eat insects. This means that we can also discard the answer choice “hummingbirds eat neither flower nectar nor insects.” It’s quite reasonable to think that the author thinks that “hummingbirds eat a mixture of flower nectar and insects” because he mentions that sometimes honey is found along with insects in hummingbirds’ stomachs. So, we need to figure out whether he probably believes that they eat mostly insects or mostly flower nectar. Let’s look at how the author phrases his description of the contents of hummingbirds’ stomachs: “in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.” So, if “in almost every instance” the hummingbird stomachs examined were “full of insects,” but “sometimes, but not generally” honey was also found, the correct answer must be “hummingbirds eat a mixture of flower nectar and insects, but mostly insects.”
This is a tricky question because in the passage, the author never directly states his opinion about what hummingbirds eat; readers have to infer it based on the evidence he presents. The author begins the passage by stating that while old scientists used to think hummingbirds ate only flower nectar, modern writers think that they eat “largely, and in some cases wholly,” on insects. He then presents evidence suggesting that hummingbirds eat insects, and in discussing the contents of hummingbirds’ stomachs, says that scientists sometimes find both insects and honey. For the rest of the paragraph, he provides evidence suggesting that hummingbirds eat insects.
What can we infer from this? Well, we can tell that it’s not likely that the author thinks hummingbirds eat only flower nectar, because he provides evidence supporting the idea that they eat insects. This means that we can also discard the answer choice “hummingbirds eat neither flower nectar nor insects.” It’s quite reasonable to think that the author thinks that “hummingbirds eat a mixture of flower nectar and insects” because he mentions that sometimes honey is found along with insects in hummingbirds’ stomachs. So, we need to figure out whether he probably believes that they eat mostly insects or mostly flower nectar. Let’s look at how the author phrases his description of the contents of hummingbirds’ stomachs: “in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.” So, if “in almost every instance” the hummingbird stomachs examined were “full of insects,” but “sometimes, but not generally” honey was also found, the correct answer must be “hummingbirds eat a mixture of flower nectar and insects, but mostly insects.”
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Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
Which of the following inferences does the passage expect its readers to make?
Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
Which of the following inferences does the passage expect its readers to make?
Tap to reveal answer
Let’s consider each of the answer choices to identify the correct one.
“The author is the first scientist to ever have investigated what hummingbirds eat.” - This cannot be true, because the author begins the passage by saying “The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects.” He also cites numerous other scientists’ opinions throughout the passage, so he can’t be the first person to have investigated what hummingbirds eat.
“Fly-catchers are a type of insect.” - The passage mentions fly-catchers in the following sentence: “Many \[hummingbirds\] in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig.” This is a tricky answer choice in that it’s easy to misread the sentence and think that “just like flycatchers” refers to “other small insects” when in fact it refers to the act of “catching.” The sentence is saying that hummingbirds catch insects in the same manner as fly-catchers, not that fly-catchers are a type of insect. Plus, we are being asked to identify an inference readers are expected to make, and if this sentence did mean that fly-catchers were insects, it would be overtly telling us this, and there would be nothing we’d have to infer.
“Scientists rarely learn about hummingbirds by dissecting them.” - This answer choice is proven wrong by the following sentence: “Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.”
“If a hummingbird eats gnats, it will not eat honey.” - Given that the questions of whether hummingbirds eat insects or honey and in what proportions is the topic of the passage, it may be easy to choose this answer choice because it seems like the one closest to the passage’s main idea; however, nothing in the passage supports this assertion.
“If a hummingbird consumes flower nectar, this nectar will turn into the honey that can be found in its stomach.” - This is the correct answer! The author initially states that “All the early writers down to Buffon believed that \[hummingbirds\] lived solely on the nectar of flowers”; however, he later states that “Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.” The author does not address the idea that flower nectar and honey could be different substances, and instead expects the reader to treat these as one source of food.
Let’s consider each of the answer choices to identify the correct one.
“The author is the first scientist to ever have investigated what hummingbirds eat.” - This cannot be true, because the author begins the passage by saying “The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects.” He also cites numerous other scientists’ opinions throughout the passage, so he can’t be the first person to have investigated what hummingbirds eat.
“Fly-catchers are a type of insect.” - The passage mentions fly-catchers in the following sentence: “Many \[hummingbirds\] in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig.” This is a tricky answer choice in that it’s easy to misread the sentence and think that “just like flycatchers” refers to “other small insects” when in fact it refers to the act of “catching.” The sentence is saying that hummingbirds catch insects in the same manner as fly-catchers, not that fly-catchers are a type of insect. Plus, we are being asked to identify an inference readers are expected to make, and if this sentence did mean that fly-catchers were insects, it would be overtly telling us this, and there would be nothing we’d have to infer.
“Scientists rarely learn about hummingbirds by dissecting them.” - This answer choice is proven wrong by the following sentence: “Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.”
“If a hummingbird eats gnats, it will not eat honey.” - Given that the questions of whether hummingbirds eat insects or honey and in what proportions is the topic of the passage, it may be easy to choose this answer choice because it seems like the one closest to the passage’s main idea; however, nothing in the passage supports this assertion.
“If a hummingbird consumes flower nectar, this nectar will turn into the honey that can be found in its stomach.” - This is the correct answer! The author initially states that “All the early writers down to Buffon believed that \[hummingbirds\] lived solely on the nectar of flowers”; however, he later states that “Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.” The author does not address the idea that flower nectar and honey could be different substances, and instead expects the reader to treat these as one source of food.
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Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
Based on the way the term is used in passage, what is “the Polytmus”?
Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
Based on the way the term is used in passage, what is “the Polytmus”?
Tap to reveal answer
Let’s look at the spot in the passage where “the Polytmus” is mentioned:
“Mr. Gosse also remarks, ‘All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail.’”
From this context, we can tell that the Polytmus isn’t a carnivorous hummingbird-eating mammal, or a species of flower: it is a hummingbird. It is mentioned in the context of flying, so it can’t refer to a fledgling hummingbird that can’t yet fly. So, is it mentioning a type of hummingbird with particularly bright coloring, or one with a long tail? Mr. Gosse mentions the Polytmus in particular because observers can easily see it contort in midair “from the effect that such motions have on the long feathers of the tail.” So, the Polytmus must be “a type of hummingbird with a long tail.”
Let’s look at the spot in the passage where “the Polytmus” is mentioned:
“Mr. Gosse also remarks, ‘All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail.’”
From this context, we can tell that the Polytmus isn’t a carnivorous hummingbird-eating mammal, or a species of flower: it is a hummingbird. It is mentioned in the context of flying, so it can’t refer to a fledgling hummingbird that can’t yet fly. So, is it mentioning a type of hummingbird with particularly bright coloring, or one with a long tail? Mr. Gosse mentions the Polytmus in particular because observers can easily see it contort in midair “from the effect that such motions have on the long feathers of the tail.” So, the Polytmus must be “a type of hummingbird with a long tail.”
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Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
What can we infer from the author’s use of the underlined phrase, “sometimes, but not generally”?
Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
What can we infer from the author’s use of the underlined phrase, “sometimes, but not generally”?
Tap to reveal answer
The phrase “sometimes, but not generally” is found in the sentence, “Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.” The phrase is specifically talking about the presence of honey in hummingbirds’ stomachs, not of insects, so we can eliminate the answer choice “Hummingbirds can be found with insects in their stomachs, but this is rare.” Since “not generally” means “not most of the time,” the author is saying “sometimes, but not most of the time, hummingbirds have honey in their stomachs.” This is only accurately stated by the answer choice “Hummingbirds can be found with honey in their stomachs, but it is not common.” The answer choices “Hummingbirds can be found with both honey and insects in their stomachs, and this is what scientists observe most often” and “Hummingbirds can be found with only honey in their stomachs quite often” are incorrect because neither suggests that finding a hummingbird with honey in its stomach is rare, which is what the author is saying.
The phrase “sometimes, but not generally” is found in the sentence, “Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.” The phrase is specifically talking about the presence of honey in hummingbirds’ stomachs, not of insects, so we can eliminate the answer choice “Hummingbirds can be found with insects in their stomachs, but this is rare.” Since “not generally” means “not most of the time,” the author is saying “sometimes, but not most of the time, hummingbirds have honey in their stomachs.” This is only accurately stated by the answer choice “Hummingbirds can be found with honey in their stomachs, but it is not common.” The answer choices “Hummingbirds can be found with both honey and insects in their stomachs, and this is what scientists observe most often” and “Hummingbirds can be found with only honey in their stomachs quite often” are incorrect because neither suggests that finding a hummingbird with honey in its stomach is rare, which is what the author is saying.
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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.
Based on the passage, which of the following can we infer would be the best reason for animals living in variable arctic environments to change their fur color?
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.
Based on the passage, which of the following can we infer would be the best reason for animals living in variable arctic environments to change their fur color?
Tap to reveal answer
If animals that live in arctic environments change their fur color, it is likely a seasonal change from brownish fur to predominantly white fur, as we’ve seen in the examples of the Irish hare, the stoat, and the weasel. What is specific about arctic environments? Thy likely involve a lot of snow, and are quite cold. Changing fur color to white would thus blend in with the snow and make an animal harder to see, as the last sentence suggests in saying that “in such an actively carnivorous creature as a stoat or weasel, \[color change\] is aggressive as well, rendering the animal inconspicuous to its prey.” we’re not told anything in the passage that would support the assertion that it would make the animal warmer, or that would support any of the other answer choices.
If animals that live in arctic environments change their fur color, it is likely a seasonal change from brownish fur to predominantly white fur, as we’ve seen in the examples of the Irish hare, the stoat, and the weasel. What is specific about arctic environments? Thy likely involve a lot of snow, and are quite cold. Changing fur color to white would thus blend in with the snow and make an animal harder to see, as the last sentence suggests in saying that “in such an actively carnivorous creature as a stoat or weasel, \[color change\] is aggressive as well, rendering the animal inconspicuous to its prey.” we’re not told anything in the passage that would support the assertion that it would make the animal warmer, or that would support any of the other answer choices.
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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.
What can we infer preceded this paragraph?
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.
What can we infer preceded this paragraph?
Tap to reveal answer
In order to infer what likely “preceded,” or came before, this passage, we should take at what the passage is talking about right when it starts. The passage’s first sentence says, “The examples of protective resemblance so far quoted are mostly permanent adaptations to one particular sort of surrounding.” The “so far quoted” means so far said or provided and tells us that the writer has been talking about “examples of protective resemblance.” This means that the writer most likely discussed “animals that defend themselves by looking like things in a stable environment” in the part of the book that comes right before the passage.
In order to infer what likely “preceded,” or came before, this passage, we should take at what the passage is talking about right when it starts. The passage’s first sentence says, “The examples of protective resemblance so far quoted are mostly permanent adaptations to one particular sort of surrounding.” The “so far quoted” means so far said or provided and tells us that the writer has been talking about “examples of protective resemblance.” This means that the writer most likely discussed “animals that defend themselves by looking like things in a stable environment” in the part of the book that comes right before the passage.
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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.
Based on the passage, what can we infer about the weasel?
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.
Based on the passage, what can we infer about the weasel?
Tap to reveal answer
The weasel is mentioned in two places in the passage, both in the passage’s last paragraph, both reproduced here:
“But in winter, the entire coat \[of the stoat\], 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.”
What does the passage tell us about the weasel? Well, we can infer that it is in some way like the stoat, because the passage says “A similar example is afforded by the weasel” right after describing how the stoat’s fur changes color. We are also told that it is carnivorous, but this is not an inference we have to make, and it doesn’t relate to any of the answer choices. The best answer choice is “Like the stoat, it also changes its coat color.” This captures the specific similarity between the stoat and weasel being discussed when the author writes, “A similar example is afforded by the weasel.”
The weasel is mentioned in two places in the passage, both in the passage’s last paragraph, both reproduced here:
“But in winter, the entire coat \[of the stoat\], 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.”
What does the passage tell us about the weasel? Well, we can infer that it is in some way like the stoat, because the passage says “A similar example is afforded by the weasel” right after describing how the stoat’s fur changes color. We are also told that it is carnivorous, but this is not an inference we have to make, and it doesn’t relate to any of the answer choices. The best answer choice is “Like the stoat, it also changes its coat color.” This captures the specific similarity between the stoat and weasel being discussed when the author writes, “A similar example is afforded by the weasel.”
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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.
In which of the following would you most expect to find this passage reprinted?
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.
In which of the following would you most expect to find this passage reprinted?
Tap to reveal answer
Where would one most likely find this article reprinted? Well, we wouldn’t be likely to find it in “a how-to manual” as it doesn’t explain how to do anything; it conveys information about certain types of animals. Similarly, since it doesn’t discuss physics or have anything to do with cooking, we can ignore the answers “A physics textbook” and “A cookbook.” This leaves us with “A scholarly report about weasels” and “An article in a biology magazine.” At this point we have to consider how the weasel is discussed in the passage—it is discussed very little, only in the context of being compared to the stoat or providing an example of carnivorous animals that change their fur color, along with the stoat. Given that the weasel isn’t the main subject of the passage, “An article in a biology magazine” is the best answer choice.
Where would one most likely find this article reprinted? Well, we wouldn’t be likely to find it in “a how-to manual” as it doesn’t explain how to do anything; it conveys information about certain types of animals. Similarly, since it doesn’t discuss physics or have anything to do with cooking, we can ignore the answers “A physics textbook” and “A cookbook.” This leaves us with “A scholarly report about weasels” and “An article in a biology magazine.” At this point we have to consider how the weasel is discussed in the passage—it is discussed very little, only in the context of being compared to the stoat or providing an example of carnivorous animals that change their fur color, along with the stoat. Given that the weasel isn’t the main subject of the passage, “An article in a biology magazine” is the best answer choice.
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"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 is implied in this passage about modern physics?
"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 is implied in this passage about modern physics?
Tap to reveal answer
The best sentence for answering this question is, "Its static laws appeared to be the unchanging principles of all motion and life on earth." The first paragraph implies that physics appeared to provide the principles needed for explaining all things. It would therefore appear to many to be the "science of sciences." (Indeed, this has been the temptation in real history as well, though that is another, complex story!)
The best sentence for answering this question is, "Its static laws appeared to be the unchanging principles of all motion and life on earth." The first paragraph implies that physics appeared to provide the principles needed for explaining all things. It would therefore appear to many to be the "science of sciences." (Indeed, this has been the temptation in real history as well, though that is another, complex story!)
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"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.
Who was most affected by the changes caused by Darwinism?
"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.
Who was most affected by the changes caused by Darwinism?
Tap to reveal answer
There have almost always been controversies about evolution, lasting to our day. Do not bring any of this to your reading of the passage; stick to the text. The general implication in the second paragraph is that everyone was affected by these changes in outlook—believers and non-believers alike. None of the limited groups listed in the answers is sufficient. Therefore, the best choice is "none of the other answers."
There have almost always been controversies about evolution, lasting to our day. Do not bring any of this to your reading of the passage; stick to the text. The general implication in the second paragraph is that everyone was affected by these changes in outlook—believers and non-believers alike. None of the limited groups listed in the answers is sufficient. Therefore, the best choice is "none of the other answers."
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"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.
Given Darwin's statements, which of the following should be expected?
"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.
Given Darwin's statements, which of the following should be expected?
Tap to reveal answer
The second paragraph of this selection mostly discusses the fact that Darwin's theories lead to the belief in the changing of creatures over time. This means that some species may never have existed. Also, it implies that new ones might have arisen. Therefore, among the options provided, the best answer is the one that says that perhaps dogs did not at one time exist.
The second paragraph of this selection mostly discusses the fact that Darwin's theories lead to the belief in the changing of creatures over time. This means that some species may never have existed. Also, it implies that new ones might have arisen. Therefore, among the options provided, the best answer is the one that says that perhaps dogs did not at one time exist.
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Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
What can we infer from the underlined sentence, “Many \[hummingbirds\] in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig"?
Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
What can we infer from the underlined sentence, “Many \[hummingbirds\] in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig"?
Tap to reveal answer
What does the underlined sentence tell us? It refers to “Many” hummingbirds, not “all hummingbirds,” so we can’t infer that what it says holds true for all hummingbirds. This allows us to eliminate the answer choices that begin with “all hummingbirds,” leaving us with “Gnats are rarely found near bodies of water,” “Some hummingbirds live in the desert,” and “Some hummingbirds live near a body of water.” Regarding gnats, the sentence doesn’t suggest that they are rarely found near bodies of water, since it mentions hummingbirds “may be seen catching gnats and other small insects just like fly-catchers” and implies that they do this by “sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig.” We’re down to two answer choices: whether some hummingbirds live in the desert or near a body of water. The sentence doesn’t mention anything about deserts; on the contrary, it tells us that “many” hummingbirds catch gnats. The way that these hummingbirds do this begins with them “sitting on a dead twig over water.” So, we are told that many hummingbirds catch gnats and that in catching gnats, they sit over water. From this, we can infer that many hummingbirds live near bodies of water.
What does the underlined sentence tell us? It refers to “Many” hummingbirds, not “all hummingbirds,” so we can’t infer that what it says holds true for all hummingbirds. This allows us to eliminate the answer choices that begin with “all hummingbirds,” leaving us with “Gnats are rarely found near bodies of water,” “Some hummingbirds live in the desert,” and “Some hummingbirds live near a body of water.” Regarding gnats, the sentence doesn’t suggest that they are rarely found near bodies of water, since it mentions hummingbirds “may be seen catching gnats and other small insects just like fly-catchers” and implies that they do this by “sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig.” We’re down to two answer choices: whether some hummingbirds live in the desert or near a body of water. The sentence doesn’t mention anything about deserts; on the contrary, it tells us that “many” hummingbirds catch gnats. The way that these hummingbirds do this begins with them “sitting on a dead twig over water.” So, we are told that many hummingbirds catch gnats and that in catching gnats, they sit over water. From this, we can infer that many hummingbirds live near bodies of water.
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"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.
What could we expect the author to discuss in a paragraph following the last paragraph of this passage?
"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.
What could we expect the author to discuss in a paragraph following the last paragraph of this passage?
Tap to reveal answer
At the beginning of the second paragraph, the passage states, "It would change even more dramatically in early twentieth-century physics as well." In general, this passage is about the general transition from one scientific outlook to another. The details of Darwinism (or of the publication of textbooks as well) is not the main concern. Likely, the author would continue his or her discussion by returning to the theme of twentieth-century physics as well.
At the beginning of the second paragraph, the passage states, "It would change even more dramatically in early twentieth-century physics as well." In general, this passage is about the general transition from one scientific outlook to another. The details of Darwinism (or of the publication of textbooks as well) is not the main concern. Likely, the author would continue his or her discussion by returning to the theme of twentieth-century physics as well.
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Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in 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)
Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort.
Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.
Which of the following can we infer based on the passage?
Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in 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)
Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort.
Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.
Which of the following can we infer based on the passage?
Tap to reveal answer
This may seem like a tricky question, but let’s consider each of the answer choices individually:
“If sailors had visited Mauritius sooner, dodos might still be alive today.”: The passage doesn’t support this assertion at all. Since the arrival of sailors on New Zealand is identified as the cause of the dodo’s extinction, it doesn’t make sense that the dodo would have survived if the sailors would have arrived earlier; it would probably have gone extinct sooner, based on the passage’s logic.
“Ostriches would likely be as effective at running away from predators in tall grass as in open country.”: The passage specific disproves this when it says of ostriches and their running abilities, “For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies.” This suggests that ostriches are better adapted to surviving in open country than in areas covered by tall grass.
“The land-rail and corn-crake are not well adapted to running through tall grass.”: The passage disproves this answer choice when it describes the ability of rails to run through tall grass: “This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants.” After this sentence, the author mentions land-rails and corn-crakes’ abilities to evade hunters, so we can assume that these birds are well adapted to running through tall grass.
“Lizards were a predator of dodos.”: This can’t be true, because the passage tells us that “The dodo . . . was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards.” Given that when animals that preyed on the dodo were introduced to Mauritius, the dodo went extinct, we can assume that since the lizards and dodos coexisted before this point, the lizards did not prey on the dodos. If this were true, the dodos would likely have learned to run or fly away, which they did not.
This brings us to the remaining answer choice, the correct one: “If predatory ground-animals had lived on Mauritius, the dodo would have probably evolved to fly or run.” The author attributes the dodo’s extinction to the fact that it did not have to adapt and defend itself from any predators before humans introduced new species on Mauritius. From this, we can infer that if those species had been present, the dodo would have learned to fly, or, like the ostrich and the rail, would have learned to run to defend itself.
This may seem like a tricky question, but let’s consider each of the answer choices individually:
“If sailors had visited Mauritius sooner, dodos might still be alive today.”: The passage doesn’t support this assertion at all. Since the arrival of sailors on New Zealand is identified as the cause of the dodo’s extinction, it doesn’t make sense that the dodo would have survived if the sailors would have arrived earlier; it would probably have gone extinct sooner, based on the passage’s logic.
“Ostriches would likely be as effective at running away from predators in tall grass as in open country.”: The passage specific disproves this when it says of ostriches and their running abilities, “For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies.” This suggests that ostriches are better adapted to surviving in open country than in areas covered by tall grass.
“The land-rail and corn-crake are not well adapted to running through tall grass.”: The passage disproves this answer choice when it describes the ability of rails to run through tall grass: “This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants.” After this sentence, the author mentions land-rails and corn-crakes’ abilities to evade hunters, so we can assume that these birds are well adapted to running through tall grass.
“Lizards were a predator of dodos.”: This can’t be true, because the passage tells us that “The dodo . . . was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards.” Given that when animals that preyed on the dodo were introduced to Mauritius, the dodo went extinct, we can assume that since the lizards and dodos coexisted before this point, the lizards did not prey on the dodos. If this were true, the dodos would likely have learned to run or fly away, which they did not.
This brings us to the remaining answer choice, the correct one: “If predatory ground-animals had lived on Mauritius, the dodo would have probably evolved to fly or run.” The author attributes the dodo’s extinction to the fact that it did not have to adapt and defend itself from any predators before humans introduced new species on Mauritius. From this, we can infer that if those species had been present, the dodo would have learned to fly, or, like the ostrich and the rail, would have learned to run to defend itself.
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Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in 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)
Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort.
Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.
According to the passage, which of the following dates could have been the year in which the dodo went extinct?
Adapted from “Birds in Retreat” in “Animal Defences—Active Defence” in 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)
Among the large running birds are forms, like the African ostrich, in which the absence of powers of flight is largely compensated by the specialization of the legs for the purpose of rapid movement on the ground. For straightforward retreat in open country nothing could be more effective; but another kind of adaptation is required in birds like rails, which are deficient in powers of flight, and yet are able to run through thickly-growing vegetation with such rapidity as to commonly elude their enemies. This is rendered possible by the shape of their bodies, which are relatively narrow and flattened from side to side, so as to easily slip between the stems of grasses, rushes, and similar plants. Anyone who has pursued our native land-rail or corn-crake with intent to capture will have noted how extremely difficult it is even to get within sight of a bird of this sort.
Certain birds, unfortunately for themselves, have lost the power of flight without correspondingly increased powers of running, and have paid the penalty of extinction. Such an arrangement, as might be anticipated, was the result of evolution in islands devoid of any predatory ground-animals, and a classic example of it is afforded by the dodo and its allies, birds related to the pigeons. The dodo itself was a large and clumsy-looking species that at one time abounded in the island of Mauritius, which, like oceanic islands generally, possessed no native mammals, while its indigenous reptiles were only represented by lizards. The ubiquitous sailor, however, and the animals (especially swine) which he introduced, brought about the extinction of this helpless bird in less than a century after its first discovery in 1598. Its memory is now only kept green by a few contemporary drawings and descriptions, certain museum remains, and the proverb "as extinct as a dodo.” A similar fate must overtake any organism suddenly exposed to new and unfavorable conditions, if devoid of sufficient plasticity to rapidly accommodate itself to the altered environment.
According to the passage, which of the following dates could have been the year in which the dodo went extinct?
Tap to reveal answer
The only date discussed in the passage appears in the second paragraph, when the author refers to “the extinction of this helpless bird in less than a century after its first discovery in 1598.” As this is referring to the extinction of the dodo, it means that the dodo had to have gone extinct some time before 1698. The only answer choice that is a date before 1698 is 1654, so “1654” is the correct answer.
The only date discussed in the passage appears in the second paragraph, when the author refers to “the extinction of this helpless bird in less than a century after its first discovery in 1598.” As this is referring to the extinction of the dodo, it means that the dodo had to have gone extinct some time before 1698. The only answer choice that is a date before 1698 is 1654, so “1654” is the correct answer.
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Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
Based on what is said in the passage, the author most likely believes that .
Adapted from “Humming-Birds: As Illustrating the Luxuriance of Tropical Nature” in Tropical Nature, and Other Essays by Alfred Russel Wallace (1878)
The food of hummingbirds has been a matter of much controversy. All the early writers down to Buffon believed that they lived solely on the nectar of flowers, but since that time, every close observer of their habits maintains that they feed largely, and in some cases wholly, on insects. Azara observed them on the La Plata in winter taking insects out of the webs of spiders at a time and place where there were no flowers. Bullock, in Mexico, declares that he saw them catch small butterflies, and that he found many kinds of insects in their stomachs. Waterton made a similar statement. Hundreds and perhaps thousands of specimens have since been dissected by collecting naturalists, and in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey. Many of them in fact may be seen catching gnats and other small insects just like fly-catchers, sitting on a dead twig over water, darting off for a time in the air, and then returning to the twig. Others come out just at dusk, and remain on the wing, now stationary, now darting about with the greatest rapidity, imitating in a limited space the evolutions of the goatsuckers, and evidently for the same end and purpose. Mr. Gosse also remarks, ” All the hummingbirds have more or less the habit, when in flight, of pausing in the air and throwing the body and tail into rapid and odd contortions. This is most observable in the Polytmus, from the effect that such motions have on the long feathers of the tail. That the object of these quick turns is the capture of insects, I am sure, having watched one thus engaged pretty close to me.”
Based on what is said in the passage, the author most likely believes that .
Tap to reveal answer
This is a tricky question because in the passage, the author never directly states his opinion about what hummingbirds eat; readers have to infer it based on the evidence he presents. The author begins the passage by stating that while old scientists used to think hummingbirds ate only flower nectar, modern writers think that they eat “largely, and in some cases wholly,” on insects. He then presents evidence suggesting that hummingbirds eat insects, and in discussing the contents of hummingbirds’ stomachs, says that scientists sometimes find both insects and honey. For the rest of the paragraph, he provides evidence suggesting that hummingbirds eat insects.
What can we infer from this? Well, we can tell that it’s not likely that the author thinks hummingbirds eat only flower nectar, because he provides evidence supporting the idea that they eat insects. This means that we can also discard the answer choice “hummingbirds eat neither flower nectar nor insects.” It’s quite reasonable to think that the author thinks that “hummingbirds eat a mixture of flower nectar and insects” because he mentions that sometimes honey is found along with insects in hummingbirds’ stomachs. So, we need to figure out whether he probably believes that they eat mostly insects or mostly flower nectar. Let’s look at how the author phrases his description of the contents of hummingbirds’ stomachs: “in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.” So, if “in almost every instance” the hummingbird stomachs examined were “full of insects,” but “sometimes, but not generally” honey was also found, the correct answer must be “hummingbirds eat a mixture of flower nectar and insects, but mostly insects.”
This is a tricky question because in the passage, the author never directly states his opinion about what hummingbirds eat; readers have to infer it based on the evidence he presents. The author begins the passage by stating that while old scientists used to think hummingbirds ate only flower nectar, modern writers think that they eat “largely, and in some cases wholly,” on insects. He then presents evidence suggesting that hummingbirds eat insects, and in discussing the contents of hummingbirds’ stomachs, says that scientists sometimes find both insects and honey. For the rest of the paragraph, he provides evidence suggesting that hummingbirds eat insects.
What can we infer from this? Well, we can tell that it’s not likely that the author thinks hummingbirds eat only flower nectar, because he provides evidence supporting the idea that they eat insects. This means that we can also discard the answer choice “hummingbirds eat neither flower nectar nor insects.” It’s quite reasonable to think that the author thinks that “hummingbirds eat a mixture of flower nectar and insects” because he mentions that sometimes honey is found along with insects in hummingbirds’ stomachs. So, we need to figure out whether he probably believes that they eat mostly insects or mostly flower nectar. Let’s look at how the author phrases his description of the contents of hummingbirds’ stomachs: “in almost every instance their stomachs have been found full of insects, sometimes, but not generally, mixed with a proportion of honey.” So, if “in almost every instance” the hummingbird stomachs examined were “full of insects,” but “sometimes, but not generally” honey was also found, the correct answer must be “hummingbirds eat a mixture of flower nectar and insects, but mostly insects.”
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