Main Ideas in Natural Science Passages - HSPT Reading
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The world described by physics is a surprisingly strange world, somewhat distant from our regular experience. Many high school students likely suspect this fact, given the difficulty that they often experience when taking physics courses. However, they are rarely instructed in the explicit difference between the world expressed by their equations and the world that they experience. Many of the concepts used in physics are related to the figures, facts, and equations that are learned in mathematics. The world is recastinto a form that looks more like a geometry problem than the world as experienced in day-to-day life. All of this at first seems strange to the budding young physics student. However, after performing a number of experiments, he or she soon sees that these mathematical formulas seem to “work.” That is, these equations really do predict the outcomes of experiments in the real world, not merely in mathematical equations on paper.
Still, it is interesting to notice some examples of how much is overlooked in these kinds of mathematical models. Most obviously, there are few (if any) objects in reality that perfectly match the form and shape of a pure geometric figure. Few physical triangles are exact triangles in the manner of the shapes used in geometric problems. Likewise, motion becomes merely something to be expressed in an equation that has time as a variable. Finally, all of the physical descriptions of light waves tell us about everything except for what it is like to experience color. This last reason is perhaps the most interesting reason of all. No matter how many equations and shapes are used to describe color, none of these will have anything to do with the experience of color itself. To speak of a “rectangular surface” or an “icosahedron-like body” does not tell us anything about colors. Rectangles and icosahedrons can be any color. That is, color does not enter into their definitions at all—a red rectangle is just as much a rectangle as is a green one.
What is author’s purpose in this passage?
The world described by physics is a surprisingly strange world, somewhat distant from our regular experience. Many high school students likely suspect this fact, given the difficulty that they often experience when taking physics courses. However, they are rarely instructed in the explicit difference between the world expressed by their equations and the world that they experience. Many of the concepts used in physics are related to the figures, facts, and equations that are learned in mathematics. The world is recastinto a form that looks more like a geometry problem than the world as experienced in day-to-day life. All of this at first seems strange to the budding young physics student. However, after performing a number of experiments, he or she soon sees that these mathematical formulas seem to “work.” That is, these equations really do predict the outcomes of experiments in the real world, not merely in mathematical equations on paper.
Still, it is interesting to notice some examples of how much is overlooked in these kinds of mathematical models. Most obviously, there are few (if any) objects in reality that perfectly match the form and shape of a pure geometric figure. Few physical triangles are exact triangles in the manner of the shapes used in geometric problems. Likewise, motion becomes merely something to be expressed in an equation that has time as a variable. Finally, all of the physical descriptions of light waves tell us about everything except for what it is like to experience color. This last reason is perhaps the most interesting reason of all. No matter how many equations and shapes are used to describe color, none of these will have anything to do with the experience of color itself. To speak of a “rectangular surface” or an “icosahedron-like body” does not tell us anything about colors. Rectangles and icosahedrons can be any color. That is, color does not enter into their definitions at all—a red rectangle is just as much a rectangle as is a green one.
What is author’s purpose in this passage?
Tap to reveal answer
First of all, note that the author does not set out to dimiss physics as false. Therefore, eliminate all of the answers that would imply that purpose. The selection merely wishes to state that physics describes the world in a strange manner. The first paragraph introduces this, showing how students come to realize this in the course of their education and also explaining general points about the mathematical nature of physics. After this, in the second paragraph, the author provides several interesting examples of how physics overlooks certain details in the world. This is not meant to critique physics, but merely to show that while it does indeed "work" for many experiments, it still cannot not tell us everything about reality.
First of all, note that the author does not set out to dimiss physics as false. Therefore, eliminate all of the answers that would imply that purpose. The selection merely wishes to state that physics describes the world in a strange manner. The first paragraph introduces this, showing how students come to realize this in the course of their education and also explaining general points about the mathematical nature of physics. After this, in the second paragraph, the author provides several interesting examples of how physics overlooks certain details in the world. This is not meant to critique physics, but merely to show that while it does indeed "work" for many experiments, it still cannot not tell us everything about reality.
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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 best states the main idea of this 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 best states the main idea of this passage?
Tap to reveal answer
When asked to identify a passage’s main idea, it is important to pick out an answer choice to which all of the paragraphs can relate, but that is not too broad in including things that the passage does not discuss. Considering if each of the answer choices falls into one or another of these categories can help you narrow down your choices. For instance, “Birds employ a variety of defenses for avoiding predators” is far too broad to accurately describer this passage’s main idea. The author only discusses flightless birds, not all birds. “Flightless birds adapt to their particular surroundings” cannot be correct either, as the first paragraph discusses this, but the second paragraph discusses a flightless bird that did not adapt to its surroundings. Since the second paragraph can’t relate to this answer, it can’t be the main idea of the entire passage. Two of the remaining answer choices can be discarded due to their being too detailed: “The African ostrich’s strong leg muscles makes it well adapted to its environment” and “The extinction of the dodo can be traced to human causes.” While the first of these choices is stated in the first paragraph and the second is stated in the second paragraph, neither relates to the other paragraph, or even adequately summarizes the entire paragraph in which it appears. This leaves us with one answer choice, the correct one: “Flightless birds sometimes develop strong running abilities, but if they don’t, they may be threatened with extinction.” Each of the two paragraphs can relate to this answer choice, but it doesn’t include things that the passage doesn’t discuss.
When asked to identify a passage’s main idea, it is important to pick out an answer choice to which all of the paragraphs can relate, but that is not too broad in including things that the passage does not discuss. Considering if each of the answer choices falls into one or another of these categories can help you narrow down your choices. For instance, “Birds employ a variety of defenses for avoiding predators” is far too broad to accurately describer this passage’s main idea. The author only discusses flightless birds, not all birds. “Flightless birds adapt to their particular surroundings” cannot be correct either, as the first paragraph discusses this, but the second paragraph discusses a flightless bird that did not adapt to its surroundings. Since the second paragraph can’t relate to this answer, it can’t be the main idea of the entire passage. Two of the remaining answer choices can be discarded due to their being too detailed: “The African ostrich’s strong leg muscles makes it well adapted to its environment” and “The extinction of the dodo can be traced to human causes.” While the first of these choices is stated in the first paragraph and the second is stated in the second paragraph, neither relates to the other paragraph, or even adequately summarizes the entire paragraph in which it appears. This leaves us with one answer choice, the correct one: “Flightless birds sometimes develop strong running abilities, but if they don’t, they may be threatened with extinction.” Each of the two paragraphs can relate to this answer choice, but it doesn’t include things that the passage doesn’t discuss.
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Adapted from On the Origin of Species by Charles Darwin (1859)
How will the struggle for existence, discussed too briefly in the last chapter, act in regard to variation? Can the principle of selection, which we have seen is so potent in the hands of man, apply in nature? I think we shall see that it can act most effectually. Let it be borne in mind in what an endless number of strange peculiarities our domestic productions, and, in a lesser degree, those under nature, vary; and how strong the hereditary tendency is. Under domestication, it may be truly said that the whole organization becomes in some degree plastic. Let it be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life. Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations? If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind? On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed. This preservation of favorable variations and the rejection of injurious variations, I call Natural Selection. Variations neither useful nor injurious would not be affected by natural selection, and would be left a fluctuating element, as perhaps we see in the species called polymorphic.
We shall best understand the probable course of natural selection by taking the case of a country undergoing some physical change, for instance, of climate. The proportional numbers of its inhabitants would almost immediately undergo a change, and some species might become extinct. We may conclude, from what we have seen of the intimate and complex manner in which the inhabitants of each country are bound together, that any change in the numerical proportions of some of the inhabitants, independently of the change of climate itself, would most seriously affect many of the others. If the country were open on its borders, new forms would certainly immigrate, and this also would seriously disturb the relations of some of the former inhabitants. Let it be remembered how powerful the influence of a single introduced tree or mammal has been shown to be. But in the case of an island, or of a country partly surrounded by barriers, into which new and better adapted forms could not freely enter, we should then have places in the economy of nature which would assuredly be better filled up, if some of the original inhabitants were in some manner modified; for, had the area been open to immigration, these same places would have been seized on by intruders. In such case, every slight modification, which in the course of ages chanced to arise, and which in any way favoured the individuals of any of the species, by better adapting them to their altered conditions, would tend to be preserved; and natural selection would thus have free scope for the work of improvement.
The main topic of this passage is .
Adapted from On the Origin of Species by Charles Darwin (1859)
How will the struggle for existence, discussed too briefly in the last chapter, act in regard to variation? Can the principle of selection, which we have seen is so potent in the hands of man, apply in nature? I think we shall see that it can act most effectually. Let it be borne in mind in what an endless number of strange peculiarities our domestic productions, and, in a lesser degree, those under nature, vary; and how strong the hereditary tendency is. Under domestication, it may be truly said that the whole organization becomes in some degree plastic. Let it be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life. Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations? If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind? On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed. This preservation of favorable variations and the rejection of injurious variations, I call Natural Selection. Variations neither useful nor injurious would not be affected by natural selection, and would be left a fluctuating element, as perhaps we see in the species called polymorphic.
We shall best understand the probable course of natural selection by taking the case of a country undergoing some physical change, for instance, of climate. The proportional numbers of its inhabitants would almost immediately undergo a change, and some species might become extinct. We may conclude, from what we have seen of the intimate and complex manner in which the inhabitants of each country are bound together, that any change in the numerical proportions of some of the inhabitants, independently of the change of climate itself, would most seriously affect many of the others. If the country were open on its borders, new forms would certainly immigrate, and this also would seriously disturb the relations of some of the former inhabitants. Let it be remembered how powerful the influence of a single introduced tree or mammal has been shown to be. But in the case of an island, or of a country partly surrounded by barriers, into which new and better adapted forms could not freely enter, we should then have places in the economy of nature which would assuredly be better filled up, if some of the original inhabitants were in some manner modified; for, had the area been open to immigration, these same places would have been seized on by intruders. In such case, every slight modification, which in the course of ages chanced to arise, and which in any way favoured the individuals of any of the species, by better adapting them to their altered conditions, would tend to be preserved; and natural selection would thus have free scope for the work of improvement.
The main topic of this passage is .
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The passage seems focused on science and the progression of species over time. The language has mostly to do with "organic beings" and their evolution over time.
The passage seems focused on science and the progression of species over time. The language has mostly to do with "organic beings" and their evolution over time.
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Adapted from The Evolutionist at Large by Grant Allen (1881)
I am engaged in watching a brigade of ants out on foraging duty, and intent on securing for the nest three whole segments of a deceased earthworm. They look for all the world like those busy companies one sees in the Egyptian wall paintings, dragging home a huge granite colossus by sheer force of bone and sinew. Every muscle in their tiny bodies is strained to the utmost as they pry themselves laboriously against the great boulders that strew the path, and that are known to our Brobdingnagian intelligence as grains of sand. Besides the workers themselves, a whole battalion of stragglers runs to and fro upon the broad line that leads to the headquarters of the community. The province of these stragglers, who seem so busy doing nothing, probably consists in keeping communications open, and encouraging the sturdy pullers by occasional relays of fresh workmen. I often wish that I could for a while get inside those tiny brains, and see, or rather smell, the world as ants do. For there can be little doubt that to these brave little carnivores here the universe is chiefly known as a collective bundle of odors, simultaneous or consecutive. As our world is mainly a world of visible objects, theirs, I believe, is mainly a world of olfactible things.
In the head of every one of these little creatures is something that we may fairly call a brain. Of course most insects have no real brains; the nerve-substance in their heads is a mere collection of ill-arranged ganglia, directly connected with their organs of sense. Whatever man may be, an earwig at least is a conscious, or rather a semi-conscious, automaton. He has just a few knots of nerve cells in his little pate, each of which leads straight from his dim eye or his vague ear or his indefinite organs of taste; and his muscles obey the promptings of external sensations without possibility of hesitation or consideration, as mechanically as the valve of a steam engine obeys the governor balls. The poor soul's intellect is wholly deficient, and the senses alone make up all that there is of him, subjectively considered. But it is not so with the highest insects. They have something that truly answers to the real brain of men, apes, and dogs, to the cerebral hemispheres and the cerebellum that are superadded in us mammals upon the simple sense-centers of lower creatures. Besides the eye, with its optic nerve and optic perceptive organs—besides the ear, with its similar mechanism—we mammalian lords of creation have a higher and more genuine brain, that collects and compares the information given to the senses, and sends down the appropriate messages to the muscles accordingly. Now, bees and flies and ants have got much the same sort of arrangement, on a smaller scale, within their tiny heads. On top of the little knots that do duty as nerve centers for their eyes and mouths, stand two stalked bits of nervous matter, whose duty is analogous to that of our own brains. And that is why these three sorts of insects think and reason so much more intellectually than beetles or butterflies, and why the larger part of them have organized their domestic arrangements on such an excellent cooperative plan.
We know well enough what forms the main material of thought with bees and flies, and that is visible objects. For you must think about something if you think at all; and you can hardly imagine a contemplative blow-fly setting itself down to reflect, like a Hindu devotee, on the syllable Om, or on the oneness of existence. Abstract ideas are not likely to play a large part in apian consciousness. A bee has a very perfect eye, and with this eye it can see not only form, but also color, as Sir John Lubbock's experiments have shown us. The information that it gets through its eye, coupled with other ideas derived from touch, smell, and taste, no doubt makes up the main thinkable and knowable universe as it reveals itself to the apian intelligence. To ourselves and to bees alike the world is, on the whole, a colored picture, with the notions of distance and solidity thrown in by touch and muscular effort; but sight undoubtedly plays the first part in forming our total conception of things generally.
What is the main idea of the first paragraph?
Adapted from The Evolutionist at Large by Grant Allen (1881)
I am engaged in watching a brigade of ants out on foraging duty, and intent on securing for the nest three whole segments of a deceased earthworm. They look for all the world like those busy companies one sees in the Egyptian wall paintings, dragging home a huge granite colossus by sheer force of bone and sinew. Every muscle in their tiny bodies is strained to the utmost as they pry themselves laboriously against the great boulders that strew the path, and that are known to our Brobdingnagian intelligence as grains of sand. Besides the workers themselves, a whole battalion of stragglers runs to and fro upon the broad line that leads to the headquarters of the community. The province of these stragglers, who seem so busy doing nothing, probably consists in keeping communications open, and encouraging the sturdy pullers by occasional relays of fresh workmen. I often wish that I could for a while get inside those tiny brains, and see, or rather smell, the world as ants do. For there can be little doubt that to these brave little carnivores here the universe is chiefly known as a collective bundle of odors, simultaneous or consecutive. As our world is mainly a world of visible objects, theirs, I believe, is mainly a world of olfactible things.
In the head of every one of these little creatures is something that we may fairly call a brain. Of course most insects have no real brains; the nerve-substance in their heads is a mere collection of ill-arranged ganglia, directly connected with their organs of sense. Whatever man may be, an earwig at least is a conscious, or rather a semi-conscious, automaton. He has just a few knots of nerve cells in his little pate, each of which leads straight from his dim eye or his vague ear or his indefinite organs of taste; and his muscles obey the promptings of external sensations without possibility of hesitation or consideration, as mechanically as the valve of a steam engine obeys the governor balls. The poor soul's intellect is wholly deficient, and the senses alone make up all that there is of him, subjectively considered. But it is not so with the highest insects. They have something that truly answers to the real brain of men, apes, and dogs, to the cerebral hemispheres and the cerebellum that are superadded in us mammals upon the simple sense-centers of lower creatures. Besides the eye, with its optic nerve and optic perceptive organs—besides the ear, with its similar mechanism—we mammalian lords of creation have a higher and more genuine brain, that collects and compares the information given to the senses, and sends down the appropriate messages to the muscles accordingly. Now, bees and flies and ants have got much the same sort of arrangement, on a smaller scale, within their tiny heads. On top of the little knots that do duty as nerve centers for their eyes and mouths, stand two stalked bits of nervous matter, whose duty is analogous to that of our own brains. And that is why these three sorts of insects think and reason so much more intellectually than beetles or butterflies, and why the larger part of them have organized their domestic arrangements on such an excellent cooperative plan.
We know well enough what forms the main material of thought with bees and flies, and that is visible objects. For you must think about something if you think at all; and you can hardly imagine a contemplative blow-fly setting itself down to reflect, like a Hindu devotee, on the syllable Om, or on the oneness of existence. Abstract ideas are not likely to play a large part in apian consciousness. A bee has a very perfect eye, and with this eye it can see not only form, but also color, as Sir John Lubbock's experiments have shown us. The information that it gets through its eye, coupled with other ideas derived from touch, smell, and taste, no doubt makes up the main thinkable and knowable universe as it reveals itself to the apian intelligence. To ourselves and to bees alike the world is, on the whole, a colored picture, with the notions of distance and solidity thrown in by touch and muscular effort; but sight undoubtedly plays the first part in forming our total conception of things generally.
What is the main idea of the first paragraph?
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The paragraph as a whole describes a scene where the author is watching ants. This leads naturally into a discussion of how they may perceive the world, particularly through their sense of smell. Although the author does wish to have a heightened sense of smell and also compares the ants to events in history, these things do not encompass the entire paragraph.
The paragraph as a whole describes a scene where the author is watching ants. This leads naturally into a discussion of how they may perceive the world, particularly through their sense of smell. Although the author does wish to have a heightened sense of smell and also compares the ants to events in history, these things do not encompass the entire paragraph.
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Adapted from The Evolutionist at Large by Grant Allen (1881)
I am engaged in watching a brigade of ants out on foraging duty, and intent on securing for the nest three whole segments of a deceased earthworm. They look for all the world like those busy companies one sees in the Egyptian wall paintings, dragging home a huge granite colossus by sheer force of bone and sinew. Every muscle in their tiny bodies is strained to the utmost as they pry themselves laboriously against the great boulders that strew the path, and that are known to our Brobdingnagian intelligence as grains of sand. Besides the workers themselves, a whole battalion of stragglers runs to and fro upon the broad line that leads to the headquarters of the community. The province of these stragglers, who seem so busy doing nothing, probably consists in keeping communications open, and encouraging the sturdy pullers by occasional relays of fresh workmen. I often wish that I could for a while get inside those tiny brains, and see, or rather smell, the world as ants do. For there can be little doubt that to these brave little carnivores here the universe is chiefly known as a collective bundle of odors, simultaneous or consecutive. As our world is mainly a world of visible objects, theirs, I believe, is mainly a world of olfactible things.
In the head of every one of these little creatures is something that we may fairly call a brain. Of course most insects have no real brains; the nerve-substance in their heads is a mere collection of ill-arranged ganglia, directly connected with their organs of sense. Whatever man may be, an earwig at least is a conscious, or rather a semi-conscious, automaton. He has just a few knots of nerve cells in his little pate, each of which leads straight from his dim eye or his vague ear or his indefinite organs of taste; and his muscles obey the promptings of external sensations without possibility of hesitation or consideration, as mechanically as the valve of a steam engine obeys the governor balls. The poor soul's intellect is wholly deficient, and the senses alone make up all that there is of him, subjectively considered. But it is not so with the highest insects. They have something that truly answers to the real brain of men, apes, and dogs, to the cerebral hemispheres and the cerebellum that are superadded in us mammals upon the simple sense-centers of lower creatures. Besides the eye, with its optic nerve and optic perceptive organs—besides the ear, with its similar mechanism—we mammalian lords of creation have a higher and more genuine brain, that collects and compares the information given to the senses, and sends down the appropriate messages to the muscles accordingly. Now, bees and flies and ants have got much the same sort of arrangement, on a smaller scale, within their tiny heads. On top of the little knots that do duty as nerve centers for their eyes and mouths, stand two stalked bits of nervous matter, whose duty is analogous to that of our own brains. And that is why these three sorts of insects think and reason so much more intellectually than beetles or butterflies, and why the larger part of them have organized their domestic arrangements on such an excellent cooperative plan.
We know well enough what forms the main material of thought with bees and flies, and that is visible objects. For you must think about something if you think at all; and you can hardly imagine a contemplative blow-fly setting itself down to reflect, like a Hindu devotee, on the syllable Om, or on the oneness of existence. Abstract ideas are not likely to play a large part in apian consciousness. A bee has a very perfect eye, and with this eye it can see not only form, but also color, as Sir John Lubbock's experiments have shown us. The information that it gets through its eye, coupled with other ideas derived from touch, smell, and taste, no doubt makes up the main thinkable and knowable universe as it reveals itself to the apian intelligence. To ourselves and to bees alike the world is, on the whole, a colored picture, with the notions of distance and solidity thrown in by touch and muscular effort; but sight undoubtedly plays the first part in forming our total conception of things generally.
The point of view from which the passage is told can best be described as that of .
Adapted from The Evolutionist at Large by Grant Allen (1881)
I am engaged in watching a brigade of ants out on foraging duty, and intent on securing for the nest three whole segments of a deceased earthworm. They look for all the world like those busy companies one sees in the Egyptian wall paintings, dragging home a huge granite colossus by sheer force of bone and sinew. Every muscle in their tiny bodies is strained to the utmost as they pry themselves laboriously against the great boulders that strew the path, and that are known to our Brobdingnagian intelligence as grains of sand. Besides the workers themselves, a whole battalion of stragglers runs to and fro upon the broad line that leads to the headquarters of the community. The province of these stragglers, who seem so busy doing nothing, probably consists in keeping communications open, and encouraging the sturdy pullers by occasional relays of fresh workmen. I often wish that I could for a while get inside those tiny brains, and see, or rather smell, the world as ants do. For there can be little doubt that to these brave little carnivores here the universe is chiefly known as a collective bundle of odors, simultaneous or consecutive. As our world is mainly a world of visible objects, theirs, I believe, is mainly a world of olfactible things.
In the head of every one of these little creatures is something that we may fairly call a brain. Of course most insects have no real brains; the nerve-substance in their heads is a mere collection of ill-arranged ganglia, directly connected with their organs of sense. Whatever man may be, an earwig at least is a conscious, or rather a semi-conscious, automaton. He has just a few knots of nerve cells in his little pate, each of which leads straight from his dim eye or his vague ear or his indefinite organs of taste; and his muscles obey the promptings of external sensations without possibility of hesitation or consideration, as mechanically as the valve of a steam engine obeys the governor balls. The poor soul's intellect is wholly deficient, and the senses alone make up all that there is of him, subjectively considered. But it is not so with the highest insects. They have something that truly answers to the real brain of men, apes, and dogs, to the cerebral hemispheres and the cerebellum that are superadded in us mammals upon the simple sense-centers of lower creatures. Besides the eye, with its optic nerve and optic perceptive organs—besides the ear, with its similar mechanism—we mammalian lords of creation have a higher and more genuine brain, that collects and compares the information given to the senses, and sends down the appropriate messages to the muscles accordingly. Now, bees and flies and ants have got much the same sort of arrangement, on a smaller scale, within their tiny heads. On top of the little knots that do duty as nerve centers for their eyes and mouths, stand two stalked bits of nervous matter, whose duty is analogous to that of our own brains. And that is why these three sorts of insects think and reason so much more intellectually than beetles or butterflies, and why the larger part of them have organized their domestic arrangements on such an excellent cooperative plan.
We know well enough what forms the main material of thought with bees and flies, and that is visible objects. For you must think about something if you think at all; and you can hardly imagine a contemplative blow-fly setting itself down to reflect, like a Hindu devotee, on the syllable Om, or on the oneness of existence. Abstract ideas are not likely to play a large part in apian consciousness. A bee has a very perfect eye, and with this eye it can see not only form, but also color, as Sir John Lubbock's experiments have shown us. The information that it gets through its eye, coupled with other ideas derived from touch, smell, and taste, no doubt makes up the main thinkable and knowable universe as it reveals itself to the apian intelligence. To ourselves and to bees alike the world is, on the whole, a colored picture, with the notions of distance and solidity thrown in by touch and muscular effort; but sight undoubtedly plays the first part in forming our total conception of things generally.
The point of view from which the passage is told can best be described as that of .
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We can tell from the detailed descriptions of the brains of mammals and insects, as well as the overall interest in the subject of ants and bees, that the author is writing from a scientific or biological viewpoint.
We can tell from the detailed descriptions of the brains of mammals and insects, as well as the overall interest in the subject of ants and bees, that the author is writing from a scientific or biological viewpoint.
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Adapted from “The Influence of the Conception of Evolution on Modern Philosophy” by H. Höffding (1909) in Evolution in Modern Thought (1917 ed.)
When The Origin of Species appeared fifty years ago, Romantic speculation, Schelling's and Hegel's philosophy, still reigned on the continent, while in England, Positivism, the philosophy of Comte and Stuart Mill, represented the most important trend of thought. German speculation had much to say on evolution; it even pretended to be a philosophy of evolution. But then the word "evolution" was to be taken in an ideal, not in a real, sense. To speculative thought, the forms and types of nature formed a system of ideas, within which any form could lead us by continuous transitions to any other. It was a classificatory system which was regarded as a divine world of thought or images, within which metamorphoses could go on—a condition comparable with that in the mind of the poet when one image follows another with imperceptible changes.
Goethe's ideas of evolution, as expressed in his Metamorphosen der Pflanzen und der Thiere, belong to this category; it is, therefore, incorrect to call him a forerunner of Darwin. Schelling and Hegel held the same idea; Hegel expressly rejected the conception of a real evolution in time as coarse and materialistic. "Nature," he says, "is to be considered as a system of stages, the one necessarily arising from the other, and being the nearest truth of that from which it proceeds; but not in such a way that the one is naturally generated by the other; on the contrary \[their connection lies\] in the inner idea which is the ground of nature. The metamorphosis can be ascribed only to the notion as such, because it alone is evolution.... It has been a clumsy idea in the older as well as in the newer philosophy of nature, to regard the transformation and the transition from one natural form and sphere to a higher as an outward and actual production."
What is the overall purpose of this selection?
Adapted from “The Influence of the Conception of Evolution on Modern Philosophy” by H. Höffding (1909) in Evolution in Modern Thought (1917 ed.)
When The Origin of Species appeared fifty years ago, Romantic speculation, Schelling's and Hegel's philosophy, still reigned on the continent, while in England, Positivism, the philosophy of Comte and Stuart Mill, represented the most important trend of thought. German speculation had much to say on evolution; it even pretended to be a philosophy of evolution. But then the word "evolution" was to be taken in an ideal, not in a real, sense. To speculative thought, the forms and types of nature formed a system of ideas, within which any form could lead us by continuous transitions to any other. It was a classificatory system which was regarded as a divine world of thought or images, within which metamorphoses could go on—a condition comparable with that in the mind of the poet when one image follows another with imperceptible changes.
Goethe's ideas of evolution, as expressed in his Metamorphosen der Pflanzen und der Thiere, belong to this category; it is, therefore, incorrect to call him a forerunner of Darwin. Schelling and Hegel held the same idea; Hegel expressly rejected the conception of a real evolution in time as coarse and materialistic. "Nature," he says, "is to be considered as a system of stages, the one necessarily arising from the other, and being the nearest truth of that from which it proceeds; but not in such a way that the one is naturally generated by the other; on the contrary \[their connection lies\] in the inner idea which is the ground of nature. The metamorphosis can be ascribed only to the notion as such, because it alone is evolution.... It has been a clumsy idea in the older as well as in the newer philosophy of nature, to regard the transformation and the transition from one natural form and sphere to a higher as an outward and actual production."
What is the overall purpose of this selection?
Tap to reveal answer
This passage opens by framing the discussion in terms of Darwin's Origin of Species. Throughout the passage, it wishes to show how the German Romantics used the word and notion of "evolution" in a way that was radically different from that used by Darwin. In this selection, at least, we are not presented with a rigorous comparison/contrast with positivism, though it is mentioned at the beginning. This whole passage focuses on how certain figures used the term in a way quite different from that of Darwin. (Note, also, that the passage does not provide a complete catalogue of positions.)
This passage opens by framing the discussion in terms of Darwin's Origin of Species. Throughout the passage, it wishes to show how the German Romantics used the word and notion of "evolution" in a way that was radically different from that used by Darwin. In this selection, at least, we are not presented with a rigorous comparison/contrast with positivism, though it is mentioned at the beginning. This whole passage focuses on how certain figures used the term in a way quite different from that of Darwin. (Note, also, that the passage does not provide a complete catalogue of positions.)
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"Interpreting the Copernican Revolution" by Matthew Minerd (2014)
The expressions of one discipline can often alter the way that other subjects understand themselves. Among such cases are numbered the investigations of Nicolaus Copernicus. Copernicus is best known for his views concerning heliocentrism, a view which eventually obliterated many aspects of the ancient/medieval worldview, at least from the standpoint of physical science. It had always been the natural view of mankind that the earth stood at the center of the universe, a fixed point in reference to the rest of the visible bodies. The sun, stars, and planets all rotated around the earth.
With time, this viewpoint became one of the major reference points for modern life. It provided a provocative image that was used—and often abused—by many people for various purposes. For those who wished to weaken the control of religion on mankind, it was said that the heliocentric outlook proved man’s insignificance. In contrast with earlier geocentrism, heliocentrism was said to show that man is not the center of the universe. He is merely one small being in the midst of a large cosmos. However, others wished to use the “Copernican Revolution” in a very different manner. These thinkers wanted to show that there was another “recentering” that had to happen. Once upon a time, we talked about the world. Now, however, it was necessary to talk of man as the central reference point. Just as the solar system was “centered” on the sun, so too should the sciences be centered on the human person.
However, both of these approaches are fraught with problems. Those who wished to undermine the religious mindset rather misunderstood the former outlook on the solar system. The earlier geocentric mindset did not believe that the earth was the most important body in the heavens. Instead, many ancient and medieval thinkers believed that the highest “sphere” above the earth was the most important being in the physical universe. Likewise, the so-called “Copernican Revolution” in physics was different from the one applied to the human person. Copernicus’ revolution showed that the human point of view was not the center, whereas the later forms of “Copernican revolution” wished to show just the opposite.
Of course, there are many complexities in the history of such important changes in scientific outlook. Nevertheless, it is fascinating to see the wide-reaching effects of such discoveries, even when they have numerous, ambiguous effects.
What does the passage say was the overall effect of the scientific revolution implied in Copernicus' discoveries?
"Interpreting the Copernican Revolution" by Matthew Minerd (2014)
The expressions of one discipline can often alter the way that other subjects understand themselves. Among such cases are numbered the investigations of Nicolaus Copernicus. Copernicus is best known for his views concerning heliocentrism, a view which eventually obliterated many aspects of the ancient/medieval worldview, at least from the standpoint of physical science. It had always been the natural view of mankind that the earth stood at the center of the universe, a fixed point in reference to the rest of the visible bodies. The sun, stars, and planets all rotated around the earth.
With time, this viewpoint became one of the major reference points for modern life. It provided a provocative image that was used—and often abused—by many people for various purposes. For those who wished to weaken the control of religion on mankind, it was said that the heliocentric outlook proved man’s insignificance. In contrast with earlier geocentrism, heliocentrism was said to show that man is not the center of the universe. He is merely one small being in the midst of a large cosmos. However, others wished to use the “Copernican Revolution” in a very different manner. These thinkers wanted to show that there was another “recentering” that had to happen. Once upon a time, we talked about the world. Now, however, it was necessary to talk of man as the central reference point. Just as the solar system was “centered” on the sun, so too should the sciences be centered on the human person.
However, both of these approaches are fraught with problems. Those who wished to undermine the religious mindset rather misunderstood the former outlook on the solar system. The earlier geocentric mindset did not believe that the earth was the most important body in the heavens. Instead, many ancient and medieval thinkers believed that the highest “sphere” above the earth was the most important being in the physical universe. Likewise, the so-called “Copernican Revolution” in physics was different from the one applied to the human person. Copernicus’ revolution showed that the human point of view was not the center, whereas the later forms of “Copernican revolution” wished to show just the opposite.
Of course, there are many complexities in the history of such important changes in scientific outlook. Nevertheless, it is fascinating to see the wide-reaching effects of such discoveries, even when they have numerous, ambiguous effects.
What does the passage say was the overall effect of the scientific revolution implied in Copernicus' discoveries?
Tap to reveal answer
Although Copernicus' discoveries had specific scientific effects, these are not the focus of this passage. From the very beginning of the selection, the passage is discussing the effects that it had on the outlook had by many people—particularly as regards the position of the human person in the cosmos. As always, stay as close to the passage as you can, otherwise you will convince yourself that another answer is possible.
Although Copernicus' discoveries had specific scientific effects, these are not the focus of this passage. From the very beginning of the selection, the passage is discussing the effects that it had on the outlook had by many people—particularly as regards the position of the human person in the cosmos. As always, stay as close to the passage as you can, otherwise you will convince yourself that another answer is possible.
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"The Multiple Sides of Computer Science" by Matthew Minerd (2014)
It often takes some time for a new discipline to become recognized as an independent science. An excellent example of this is computer science. In many ways, this science still is a hodgepodge of several different sciences, each one having its own distinct character. For example, some computer scientists are almost indistinguishable from mathematicians. Many of the most difficult topics in pattern recognition and data communications require intensive mathematics in order to provide software solutions. Years of training in the appropriate disciplines are necessary before the computer scientist can even begin to work as a programmer in such areas. In contrast to those computer scientists who work with complex mathematics, many computer scientists work on areas of hardware development that are similar to disciplines like electrical engineering and physics.
However, computer science has its own particular problems regarding the unity of its subject matter. There are many practical applications for computing work; therefore, many computer scientists focus on learning a large set of skills in programming languages, development environments, and even information technology. All of these disciplines have a certain practical coloration that is quite distinct from the theoretical concepts used in other parts of the field. Nevertheless, these practical topics add to the broad range of topics covered by most academic programs that claim to focus on “computer science.” It can only be hoped that these disciplines will increase in orderliness in the coming decades.
What is the main point introduced in the second paragraph?
"The Multiple Sides of Computer Science" by Matthew Minerd (2014)
It often takes some time for a new discipline to become recognized as an independent science. An excellent example of this is computer science. In many ways, this science still is a hodgepodge of several different sciences, each one having its own distinct character. For example, some computer scientists are almost indistinguishable from mathematicians. Many of the most difficult topics in pattern recognition and data communications require intensive mathematics in order to provide software solutions. Years of training in the appropriate disciplines are necessary before the computer scientist can even begin to work as a programmer in such areas. In contrast to those computer scientists who work with complex mathematics, many computer scientists work on areas of hardware development that are similar to disciplines like electrical engineering and physics.
However, computer science has its own particular problems regarding the unity of its subject matter. There are many practical applications for computing work; therefore, many computer scientists focus on learning a large set of skills in programming languages, development environments, and even information technology. All of these disciplines have a certain practical coloration that is quite distinct from the theoretical concepts used in other parts of the field. Nevertheless, these practical topics add to the broad range of topics covered by most academic programs that claim to focus on “computer science.” It can only be hoped that these disciplines will increase in orderliness in the coming decades.
What is the main point introduced in the second paragraph?
Tap to reveal answer
The second paragraph focuses on the fact that computer science has a host of practical applications. In particular, these practical applications make it even more difficult to see the focus of computer science studies. Therefore, they tend to hide the unity of the topic even more (that is, even beyond the more "academic" issues discussed in the first paragraph).
The second paragraph focuses on the fact that computer science has a host of practical applications. In particular, these practical applications make it even more difficult to see the focus of computer science studies. Therefore, they tend to hide the unity of the topic even more (that is, even beyond the more "academic" issues discussed in the first paragraph).
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Adapted from "Some Strange Nurseries" by Grant Allen in A Book of Natural History (1902, ed. David Starr Jordan)
Many different types of animals employ one of two strategies in raising their young. Certain animals, called “r-strategists,” turn out thousands of eggs with reckless profusion, but they let them look after themselves, or be devoured by enemies, as chance will have it. Other animals, called “K-strategists,” take greater pain in the rearing and upbringing of the young. Large broods indicate an “r” life strategy; small broods imply a “K” life strategy and more care in the nurture and education of the offspring. R-strategists produce eggs wholesale, on the off chance that some two or three among them may perhaps survive an infant mortality of ninety-nine per cent, so as to replace their parents. K-strategists produce half a dozen young, or less, but bring a large proportion of these on an average up to years of discretion.
Which of these extracts best captures the main idea of this passage?
Adapted from "Some Strange Nurseries" by Grant Allen in A Book of Natural History (1902, ed. David Starr Jordan)
Many different types of animals employ one of two strategies in raising their young. Certain animals, called “r-strategists,” turn out thousands of eggs with reckless profusion, but they let them look after themselves, or be devoured by enemies, as chance will have it. Other animals, called “K-strategists,” take greater pain in the rearing and upbringing of the young. Large broods indicate an “r” life strategy; small broods imply a “K” life strategy and more care in the nurture and education of the offspring. R-strategists produce eggs wholesale, on the off chance that some two or three among them may perhaps survive an infant mortality of ninety-nine per cent, so as to replace their parents. K-strategists produce half a dozen young, or less, but bring a large proportion of these on an average up to years of discretion.
Which of these extracts best captures the main idea of this passage?
Tap to reveal answer
The main idea of this essay is that there is a direct correlation between the number of offspring a species generally produces and the type of life strategy that species employs. This idea is really only captured in the first sentence, ""Many different types of animals employ one of two strategies in raising their young." Another sentence might be better if it compared both r-strategists and K-strategists, but the other four answer choices are less succinct and direct, and usually only make half the author’s point.
The main idea of this essay is that there is a direct correlation between the number of offspring a species generally produces and the type of life strategy that species employs. This idea is really only captured in the first sentence, ""Many different types of animals employ one of two strategies in raising their young." Another sentence might be better if it compared both r-strategists and K-strategists, but the other four answer choices are less succinct and direct, and usually only make half the author’s point.
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Adapted from "How the Soil is Made" by Charles Darwin in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)
Worms have played a more important part in the history of the world than most persons would at first suppose. In almost all humid countries they are extraordinarily numerous, and for their size possess great muscular power. In many parts of England a weight of more than ten tons (10,516 kilograms) of dry earth annually passes through their bodies and is brought to the surface on each acre of land, so that the whole superficial bed of vegetable mould passes through their bodies in the course of every few years. From the collapsing of the old burrows, the mold is in constant though slow movement, and the particles composing it are thus rubbed together. Thus the particles of earth, forming the superficial mold, are subjected to conditions eminently favorable for their decomposition and disintegration. This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.
Worms are poorly provided with sense-organs, for they cannot be said to see, although they can just distinguish between light and darkness; they are completely deaf, and have only a feeble power of smell; the sense of touch alone is well developed. They can, therefore, learn little about the outside world, and it is surprising that they should exhibit some skill in lining their burrows with their castings and with leaves, and in the case of some species in piling up their castings into tower-like constructions. But it is far more surprising that they should apparently exhibit some degree of intelligence instead of a mere blind, instinctive impulse, in their manner of plugging up the mouths of their burrows. They act in nearly the same manner as would a man, who had to close a cylindrical tube with different kinds of leaves, petioles, triangles of paper, etc., for they commonly seize such objects by their pointed ends. But with thin objects a certain number are drawn in by their broader ends. They do not act in the same unvarying manner in all cases, as do most of the lower animals.
What “important part in the history of the world” does the author believe worms have played?
Adapted from "How the Soil is Made" by Charles Darwin in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)
Worms have played a more important part in the history of the world than most persons would at first suppose. In almost all humid countries they are extraordinarily numerous, and for their size possess great muscular power. In many parts of England a weight of more than ten tons (10,516 kilograms) of dry earth annually passes through their bodies and is brought to the surface on each acre of land, so that the whole superficial bed of vegetable mould passes through their bodies in the course of every few years. From the collapsing of the old burrows, the mold is in constant though slow movement, and the particles composing it are thus rubbed together. Thus the particles of earth, forming the superficial mold, are subjected to conditions eminently favorable for their decomposition and disintegration. This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.
Worms are poorly provided with sense-organs, for they cannot be said to see, although they can just distinguish between light and darkness; they are completely deaf, and have only a feeble power of smell; the sense of touch alone is well developed. They can, therefore, learn little about the outside world, and it is surprising that they should exhibit some skill in lining their burrows with their castings and with leaves, and in the case of some species in piling up their castings into tower-like constructions. But it is far more surprising that they should apparently exhibit some degree of intelligence instead of a mere blind, instinctive impulse, in their manner of plugging up the mouths of their burrows. They act in nearly the same manner as would a man, who had to close a cylindrical tube with different kinds of leaves, petioles, triangles of paper, etc., for they commonly seize such objects by their pointed ends. But with thin objects a certain number are drawn in by their broader ends. They do not act in the same unvarying manner in all cases, as do most of the lower animals.
What “important part in the history of the world” does the author believe worms have played?
Tap to reveal answer
The first paragraph is essentially one long explanation about the very important role that worms have played in history of the world. The author begins by saying “Worms have played a more important part in the history of the world than most persons would at first suppose.” The author then goes on to describe the process by which they play this “important part.” And, finally, he concludes by saying “This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.” The key is to focus on the relationship between the opening and closing sentences of the first paragraph.
The first paragraph is essentially one long explanation about the very important role that worms have played in history of the world. The author begins by saying “Worms have played a more important part in the history of the world than most persons would at first suppose.” The author then goes on to describe the process by which they play this “important part.” And, finally, he concludes by saying “This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.” The key is to focus on the relationship between the opening and closing sentences of the first paragraph.
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Adapted from "Errors in Our Food Economy" in Scientific American Supplement No. 1082 Vol. XLII (September 26th, 1896)
Scientific research, interpreting the observations of practical life, implies that several errors are common in the use of food.
First, many people purchase needlessly expensive kinds of food, doing this under the false impression that there is some peculiar virtue in the costlier materials, and that economy in our diet is somehow detrimental to our dignity or our welfare. And, unfortunately, those who are most extravagant in this respect are often the ones who can least afford it.
Secondly, the food which we eat does not always contain the proper proportions of the different kinds of nutritive ingredients. We consume relatively too much of the fuel ingredients of food, such as the fats of meat and butter, and the starch which makes up the larger part of the nutritive material of flour, potatoes, sugar, and sweetmeats. Conversely, we have relatively too little of the protein of flesh-forming substances, like the lean of meat and fish and the gluten of wheat, which make muscle and sinew and which are the basis of blood, bone and brain.
Thirdly, many people, not only the well-to-do, but those in moderate circumstances, use needless quantities of food. Part of the excess, however, is simply thrown away with the wastes of the table and the kitchen; so that the injury to health, great as it may be, is doubtless much less than if all were eaten. Probably the worst sufferers from this evil are well-to-do people of sedentary occupations.
Finally, we are guilty of serious errors in our cooking. We waste a great deal of fuel in the preparation of our food, and even then a great deal of the food is very badly cooked. A reform in these methods of cooking is one of the economic demands of our time.
The primary theme of this essay is that .
Adapted from "Errors in Our Food Economy" in Scientific American Supplement No. 1082 Vol. XLII (September 26th, 1896)
Scientific research, interpreting the observations of practical life, implies that several errors are common in the use of food.
First, many people purchase needlessly expensive kinds of food, doing this under the false impression that there is some peculiar virtue in the costlier materials, and that economy in our diet is somehow detrimental to our dignity or our welfare. And, unfortunately, those who are most extravagant in this respect are often the ones who can least afford it.
Secondly, the food which we eat does not always contain the proper proportions of the different kinds of nutritive ingredients. We consume relatively too much of the fuel ingredients of food, such as the fats of meat and butter, and the starch which makes up the larger part of the nutritive material of flour, potatoes, sugar, and sweetmeats. Conversely, we have relatively too little of the protein of flesh-forming substances, like the lean of meat and fish and the gluten of wheat, which make muscle and sinew and which are the basis of blood, bone and brain.
Thirdly, many people, not only the well-to-do, but those in moderate circumstances, use needless quantities of food. Part of the excess, however, is simply thrown away with the wastes of the table and the kitchen; so that the injury to health, great as it may be, is doubtless much less than if all were eaten. Probably the worst sufferers from this evil are well-to-do people of sedentary occupations.
Finally, we are guilty of serious errors in our cooking. We waste a great deal of fuel in the preparation of our food, and even then a great deal of the food is very badly cooked. A reform in these methods of cooking is one of the economic demands of our time.
The primary theme of this essay is that .
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While it is true that the differences between wealthy people and poor people in the purchase, preparation, and consumption of food is an important theme in this text, it is more accurate to say that the primary theme is that all “humans misuse their food resources heavily.“ The author employs examples of the ways in which poor and wealthy people both do this to demonstrate that this mistake is not unique to one or the other, but rather is a universal tendency of humanity.
While it is true that the differences between wealthy people and poor people in the purchase, preparation, and consumption of food is an important theme in this text, it is more accurate to say that the primary theme is that all “humans misuse their food resources heavily.“ The author employs examples of the ways in which poor and wealthy people both do this to demonstrate that this mistake is not unique to one or the other, but rather is a universal tendency of humanity.
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Adapted from The Principles of Breeding by S. L. Goodale (1861)
The Jersey cow, formerly known as the Alderney, is almost exclusively employed for dairy purposes, and may not be expected to give satisfaction for other uses. Their milk is richer than that of any other cows, and the butter made from it possesses a superior flavor and a deep rich color, and consequently commands an extraordinary price in all markets where good butter is appreciated.
Jersey cattle are of Norman origin, and are noted for their milking properties. The cows are generally very docile and gentle, but the males when past two or three years of age often become vicious and unmanageable. It is said that the cows fatten readily when dry.
There is no branch of cattle husbandry which promises better returns than the breeding and rearing of milch cows. In the vicinity of large towns and cities are many cows which having been culled from many miles around, on account of dairy properties, are considerably above the average, but taking the cows of the country together they do not compare favorably with the oxen. Farmers generally take more pride in their oxen, and strive to have as good or better than any of their neighbors, while if a cow will give milk enough to rear a large steer calf and a little besides, it is often deemed satisfactory.
The main purpose of this article is .
Adapted from The Principles of Breeding by S. L. Goodale (1861)
The Jersey cow, formerly known as the Alderney, is almost exclusively employed for dairy purposes, and may not be expected to give satisfaction for other uses. Their milk is richer than that of any other cows, and the butter made from it possesses a superior flavor and a deep rich color, and consequently commands an extraordinary price in all markets where good butter is appreciated.
Jersey cattle are of Norman origin, and are noted for their milking properties. The cows are generally very docile and gentle, but the males when past two or three years of age often become vicious and unmanageable. It is said that the cows fatten readily when dry.
There is no branch of cattle husbandry which promises better returns than the breeding and rearing of milch cows. In the vicinity of large towns and cities are many cows which having been culled from many miles around, on account of dairy properties, are considerably above the average, but taking the cows of the country together they do not compare favorably with the oxen. Farmers generally take more pride in their oxen, and strive to have as good or better than any of their neighbors, while if a cow will give milk enough to rear a large steer calf and a little besides, it is often deemed satisfactory.
The main purpose of this article is .
Tap to reveal answer
In the first two paragraphs, the author primarily describes the properties of the Jersey cow, but his reason for doing so is to make an argument encouraging the greater selective breeding of dairy cows. This can be seen, for example, when the author says “There is no branch of cattle husbandry which promises better returns than the breeding and rearing of milch cows.” You can then see how the third paragraph is primarily a discussion of how farmers err by not focusing more of their attention in selectively breeding their dairy cows.
In the first two paragraphs, the author primarily describes the properties of the Jersey cow, but his reason for doing so is to make an argument encouraging the greater selective breeding of dairy cows. This can be seen, for example, when the author says “There is no branch of cattle husbandry which promises better returns than the breeding and rearing of milch cows.” You can then see how the third paragraph is primarily a discussion of how farmers err by not focusing more of their attention in selectively breeding their dairy cows.
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Adapted from "Some Strange Nurseries" by Grant Allen in A Book of Natural History (1902, ed. David Starr Jordan)
Many different types of animals employ one of two strategies in raising their young. Certain animals, called “r-strategists,” turn out thousands of eggs with reckless profusion, but they let them look after themselves, or be devoured by enemies, as chance will have it. Other animals, called “K-strategists,” take greater pain in the rearing and upbringing of the young. Large broods indicate an “r” life strategy; small broods imply a “K” life strategy and more care in the nurture and education of the offspring. R-strategists produce eggs wholesale, on the off chance that some two or three among them may perhaps survive an infant mortality of ninety-nine per cent, so as to replace their parents. K-strategists produce half a dozen young, or less, but bring a large proportion of these on an average up to years of discretion.
Which of these extracts best captures the main idea of this passage?
Adapted from "Some Strange Nurseries" by Grant Allen in A Book of Natural History (1902, ed. David Starr Jordan)
Many different types of animals employ one of two strategies in raising their young. Certain animals, called “r-strategists,” turn out thousands of eggs with reckless profusion, but they let them look after themselves, or be devoured by enemies, as chance will have it. Other animals, called “K-strategists,” take greater pain in the rearing and upbringing of the young. Large broods indicate an “r” life strategy; small broods imply a “K” life strategy and more care in the nurture and education of the offspring. R-strategists produce eggs wholesale, on the off chance that some two or three among them may perhaps survive an infant mortality of ninety-nine per cent, so as to replace their parents. K-strategists produce half a dozen young, or less, but bring a large proportion of these on an average up to years of discretion.
Which of these extracts best captures the main idea of this passage?
Tap to reveal answer
The main idea of this essay is that there is a direct correlation between the number of offspring a species generally produces and the type of life strategy that species employs. This idea is really only captured in the first sentence, ""Many different types of animals employ one of two strategies in raising their young." Another sentence might be better if it compared both r-strategists and K-strategists, but the other four answer choices are less succinct and direct, and usually only make half the author’s point.
The main idea of this essay is that there is a direct correlation between the number of offspring a species generally produces and the type of life strategy that species employs. This idea is really only captured in the first sentence, ""Many different types of animals employ one of two strategies in raising their young." Another sentence might be better if it compared both r-strategists and K-strategists, but the other four answer choices are less succinct and direct, and usually only make half the author’s point.
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Adapted from "How the Soil is Made" by Charles Darwin in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)
Worms have played a more important part in the history of the world than most persons would at first suppose. In almost all humid countries they are extraordinarily numerous, and for their size possess great muscular power. In many parts of England a weight of more than ten tons (10,516 kilograms) of dry earth annually passes through their bodies and is brought to the surface on each acre of land, so that the whole superficial bed of vegetable mould passes through their bodies in the course of every few years. From the collapsing of the old burrows, the mold is in constant though slow movement, and the particles composing it are thus rubbed together. Thus the particles of earth, forming the superficial mold, are subjected to conditions eminently favorable for their decomposition and disintegration. This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.
Worms are poorly provided with sense-organs, for they cannot be said to see, although they can just distinguish between light and darkness; they are completely deaf, and have only a feeble power of smell; the sense of touch alone is well developed. They can, therefore, learn little about the outside world, and it is surprising that they should exhibit some skill in lining their burrows with their castings and with leaves, and in the case of some species in piling up their castings into tower-like constructions. But it is far more surprising that they should apparently exhibit some degree of intelligence instead of a mere blind, instinctive impulse, in their manner of plugging up the mouths of their burrows. They act in nearly the same manner as would a man, who had to close a cylindrical tube with different kinds of leaves, petioles, triangles of paper, etc., for they commonly seize such objects by their pointed ends. But with thin objects a certain number are drawn in by their broader ends. They do not act in the same unvarying manner in all cases, as do most of the lower animals.
What “important part in the history of the world” does the author believe worms have played?
Adapted from "How the Soil is Made" by Charles Darwin in Wonders of Earth, Sea, and Sky (1902, ed. Edward Singleton Holden)
Worms have played a more important part in the history of the world than most persons would at first suppose. In almost all humid countries they are extraordinarily numerous, and for their size possess great muscular power. In many parts of England a weight of more than ten tons (10,516 kilograms) of dry earth annually passes through their bodies and is brought to the surface on each acre of land, so that the whole superficial bed of vegetable mould passes through their bodies in the course of every few years. From the collapsing of the old burrows, the mold is in constant though slow movement, and the particles composing it are thus rubbed together. Thus the particles of earth, forming the superficial mold, are subjected to conditions eminently favorable for their decomposition and disintegration. This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.
Worms are poorly provided with sense-organs, for they cannot be said to see, although they can just distinguish between light and darkness; they are completely deaf, and have only a feeble power of smell; the sense of touch alone is well developed. They can, therefore, learn little about the outside world, and it is surprising that they should exhibit some skill in lining their burrows with their castings and with leaves, and in the case of some species in piling up their castings into tower-like constructions. But it is far more surprising that they should apparently exhibit some degree of intelligence instead of a mere blind, instinctive impulse, in their manner of plugging up the mouths of their burrows. They act in nearly the same manner as would a man, who had to close a cylindrical tube with different kinds of leaves, petioles, triangles of paper, etc., for they commonly seize such objects by their pointed ends. But with thin objects a certain number are drawn in by their broader ends. They do not act in the same unvarying manner in all cases, as do most of the lower animals.
What “important part in the history of the world” does the author believe worms have played?
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The first paragraph is essentially one long explanation about the very important role that worms have played in history of the world. The author begins by saying “Worms have played a more important part in the history of the world than most persons would at first suppose.” The author then goes on to describe the process by which they play this “important part.” And, finally, he concludes by saying “This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.” The key is to focus on the relationship between the opening and closing sentences of the first paragraph.
The first paragraph is essentially one long explanation about the very important role that worms have played in history of the world. The author begins by saying “Worms have played a more important part in the history of the world than most persons would at first suppose.” The author then goes on to describe the process by which they play this “important part.” And, finally, he concludes by saying “This keeps the surface of the earth perfectly suited to the growth of an abundant array of fruits and vegetables.” The key is to focus on the relationship between the opening and closing sentences of the first paragraph.
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Adapted from "Errors in Our Food Economy" in Scientific American Supplement No. 1082 Vol. XLII (September 26th, 1896)
Scientific research, interpreting the observations of practical life, implies that several errors are common in the use of food.
First, many people purchase needlessly expensive kinds of food, doing this under the false impression that there is some peculiar virtue in the costlier materials, and that economy in our diet is somehow detrimental to our dignity or our welfare. And, unfortunately, those who are most extravagant in this respect are often the ones who can least afford it.
Secondly, the food which we eat does not always contain the proper proportions of the different kinds of nutritive ingredients. We consume relatively too much of the fuel ingredients of food, such as the fats of meat and butter, and the starch which makes up the larger part of the nutritive material of flour, potatoes, sugar, and sweetmeats. Conversely, we have relatively too little of the protein of flesh-forming substances, like the lean of meat and fish and the gluten of wheat, which make muscle and sinew and which are the basis of blood, bone and brain.
Thirdly, many people, not only the well-to-do, but those in moderate circumstances, use needless quantities of food. Part of the excess, however, is simply thrown away with the wastes of the table and the kitchen; so that the injury to health, great as it may be, is doubtless much less than if all were eaten. Probably the worst sufferers from this evil are well-to-do people of sedentary occupations.
Finally, we are guilty of serious errors in our cooking. We waste a great deal of fuel in the preparation of our food, and even then a great deal of the food is very badly cooked. A reform in these methods of cooking is one of the economic demands of our time.
The primary theme of this essay is that .
Adapted from "Errors in Our Food Economy" in Scientific American Supplement No. 1082 Vol. XLII (September 26th, 1896)
Scientific research, interpreting the observations of practical life, implies that several errors are common in the use of food.
First, many people purchase needlessly expensive kinds of food, doing this under the false impression that there is some peculiar virtue in the costlier materials, and that economy in our diet is somehow detrimental to our dignity or our welfare. And, unfortunately, those who are most extravagant in this respect are often the ones who can least afford it.
Secondly, the food which we eat does not always contain the proper proportions of the different kinds of nutritive ingredients. We consume relatively too much of the fuel ingredients of food, such as the fats of meat and butter, and the starch which makes up the larger part of the nutritive material of flour, potatoes, sugar, and sweetmeats. Conversely, we have relatively too little of the protein of flesh-forming substances, like the lean of meat and fish and the gluten of wheat, which make muscle and sinew and which are the basis of blood, bone and brain.
Thirdly, many people, not only the well-to-do, but those in moderate circumstances, use needless quantities of food. Part of the excess, however, is simply thrown away with the wastes of the table and the kitchen; so that the injury to health, great as it may be, is doubtless much less than if all were eaten. Probably the worst sufferers from this evil are well-to-do people of sedentary occupations.
Finally, we are guilty of serious errors in our cooking. We waste a great deal of fuel in the preparation of our food, and even then a great deal of the food is very badly cooked. A reform in these methods of cooking is one of the economic demands of our time.
The primary theme of this essay is that .
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While it is true that the differences between wealthy people and poor people in the purchase, preparation, and consumption of food is an important theme in this text, it is more accurate to say that the primary theme is that all “humans misuse their food resources heavily.“ The author employs examples of the ways in which poor and wealthy people both do this to demonstrate that this mistake is not unique to one or the other, but rather is a universal tendency of humanity.
While it is true that the differences between wealthy people and poor people in the purchase, preparation, and consumption of food is an important theme in this text, it is more accurate to say that the primary theme is that all “humans misuse their food resources heavily.“ The author employs examples of the ways in which poor and wealthy people both do this to demonstrate that this mistake is not unique to one or the other, but rather is a universal tendency of humanity.
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Adapted from The Principles of Breeding by S. L. Goodale (1861)
The Jersey cow, formerly known as the Alderney, is almost exclusively employed for dairy purposes, and may not be expected to give satisfaction for other uses. Their milk is richer than that of any other cows, and the butter made from it possesses a superior flavor and a deep rich color, and consequently commands an extraordinary price in all markets where good butter is appreciated.
Jersey cattle are of Norman origin, and are noted for their milking properties. The cows are generally very docile and gentle, but the males when past two or three years of age often become vicious and unmanageable. It is said that the cows fatten readily when dry.
There is no branch of cattle husbandry which promises better returns than the breeding and rearing of milch cows. In the vicinity of large towns and cities are many cows which having been culled from many miles around, on account of dairy properties, are considerably above the average, but taking the cows of the country together they do not compare favorably with the oxen. Farmers generally take more pride in their oxen, and strive to have as good or better than any of their neighbors, while if a cow will give milk enough to rear a large steer calf and a little besides, it is often deemed satisfactory.
The main purpose of this article is .
Adapted from The Principles of Breeding by S. L. Goodale (1861)
The Jersey cow, formerly known as the Alderney, is almost exclusively employed for dairy purposes, and may not be expected to give satisfaction for other uses. Their milk is richer than that of any other cows, and the butter made from it possesses a superior flavor and a deep rich color, and consequently commands an extraordinary price in all markets where good butter is appreciated.
Jersey cattle are of Norman origin, and are noted for their milking properties. The cows are generally very docile and gentle, but the males when past two or three years of age often become vicious and unmanageable. It is said that the cows fatten readily when dry.
There is no branch of cattle husbandry which promises better returns than the breeding and rearing of milch cows. In the vicinity of large towns and cities are many cows which having been culled from many miles around, on account of dairy properties, are considerably above the average, but taking the cows of the country together they do not compare favorably with the oxen. Farmers generally take more pride in their oxen, and strive to have as good or better than any of their neighbors, while if a cow will give milk enough to rear a large steer calf and a little besides, it is often deemed satisfactory.
The main purpose of this article is .
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In the first two paragraphs, the author primarily describes the properties of the Jersey cow, but his reason for doing so is to make an argument encouraging the greater selective breeding of dairy cows. This can be seen, for example, when the author says “There is no branch of cattle husbandry which promises better returns than the breeding and rearing of milch cows.” You can then see how the third paragraph is primarily a discussion of how farmers err by not focusing more of their attention in selectively breeding their dairy cows.
In the first two paragraphs, the author primarily describes the properties of the Jersey cow, but his reason for doing so is to make an argument encouraging the greater selective breeding of dairy cows. This can be seen, for example, when the author says “There is no branch of cattle husbandry which promises better returns than the breeding and rearing of milch cows.” You can then see how the third paragraph is primarily a discussion of how farmers err by not focusing more of their attention in selectively breeding their dairy cows.
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The world described by physics is a surprisingly strange world, somewhat distant from our regular experience. Many high school students likely suspect this fact, given the difficulty that they often experience when taking physics courses. However, they are rarely instructed in the explicit difference between the world expressed by their equations and the world that they experience. Many of the concepts used in physics are related to the figures, facts, and equations that are learned in mathematics. The world is recastinto a form that looks more like a geometry problem than the world as experienced in day-to-day life. All of this at first seems strange to the budding young physics student. However, after performing a number of experiments, he or she soon sees that these mathematical formulas seem to “work.” That is, these equations really do predict the outcomes of experiments in the real world, not merely in mathematical equations on paper.
Still, it is interesting to notice some examples of how much is overlooked in these kinds of mathematical models. Most obviously, there are few (if any) objects in reality that perfectly match the form and shape of a pure geometric figure. Few physical triangles are exact triangles in the manner of the shapes used in geometric problems. Likewise, motion becomes merely something to be expressed in an equation that has time as a variable. Finally, all of the physical descriptions of light waves tell us about everything except for what it is like to experience color. This last reason is perhaps the most interesting reason of all. No matter how many equations and shapes are used to describe color, none of these will have anything to do with the experience of color itself. To speak of a “rectangular surface” or an “icosahedron-like body” does not tell us anything about colors. Rectangles and icosahedrons can be any color. That is, color does not enter into their definitions at all—a red rectangle is just as much a rectangle as is a green one.
What is author’s purpose in this passage?
The world described by physics is a surprisingly strange world, somewhat distant from our regular experience. Many high school students likely suspect this fact, given the difficulty that they often experience when taking physics courses. However, they are rarely instructed in the explicit difference between the world expressed by their equations and the world that they experience. Many of the concepts used in physics are related to the figures, facts, and equations that are learned in mathematics. The world is recastinto a form that looks more like a geometry problem than the world as experienced in day-to-day life. All of this at first seems strange to the budding young physics student. However, after performing a number of experiments, he or she soon sees that these mathematical formulas seem to “work.” That is, these equations really do predict the outcomes of experiments in the real world, not merely in mathematical equations on paper.
Still, it is interesting to notice some examples of how much is overlooked in these kinds of mathematical models. Most obviously, there are few (if any) objects in reality that perfectly match the form and shape of a pure geometric figure. Few physical triangles are exact triangles in the manner of the shapes used in geometric problems. Likewise, motion becomes merely something to be expressed in an equation that has time as a variable. Finally, all of the physical descriptions of light waves tell us about everything except for what it is like to experience color. This last reason is perhaps the most interesting reason of all. No matter how many equations and shapes are used to describe color, none of these will have anything to do with the experience of color itself. To speak of a “rectangular surface” or an “icosahedron-like body” does not tell us anything about colors. Rectangles and icosahedrons can be any color. That is, color does not enter into their definitions at all—a red rectangle is just as much a rectangle as is a green one.
What is author’s purpose in this passage?
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First of all, note that the author does not set out to dimiss physics as false. Therefore, eliminate all of the answers that would imply that purpose. The selection merely wishes to state that physics describes the world in a strange manner. The first paragraph introduces this, showing how students come to realize this in the course of their education and also explaining general points about the mathematical nature of physics. After this, in the second paragraph, the author provides several interesting examples of how physics overlooks certain details in the world. This is not meant to critique physics, but merely to show that while it does indeed "work" for many experiments, it still cannot not tell us everything about reality.
First of all, note that the author does not set out to dimiss physics as false. Therefore, eliminate all of the answers that would imply that purpose. The selection merely wishes to state that physics describes the world in a strange manner. The first paragraph introduces this, showing how students come to realize this in the course of their education and also explaining general points about the mathematical nature of physics. After this, in the second paragraph, the author provides several interesting examples of how physics overlooks certain details in the world. This is not meant to critique physics, but merely to show that while it does indeed "work" for many experiments, it still cannot not tell us everything about reality.
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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 best states the main idea of this 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 best states the main idea of this passage?
Tap to reveal answer
When asked to identify a passage’s main idea, it is important to pick out an answer choice to which all of the paragraphs can relate, but that is not too broad in including things that the passage does not discuss. Considering if each of the answer choices falls into one or another of these categories can help you narrow down your choices. For instance, “Birds employ a variety of defenses for avoiding predators” is far too broad to accurately describer this passage’s main idea. The author only discusses flightless birds, not all birds. “Flightless birds adapt to their particular surroundings” cannot be correct either, as the first paragraph discusses this, but the second paragraph discusses a flightless bird that did not adapt to its surroundings. Since the second paragraph can’t relate to this answer, it can’t be the main idea of the entire passage. Two of the remaining answer choices can be discarded due to their being too detailed: “The African ostrich’s strong leg muscles makes it well adapted to its environment” and “The extinction of the dodo can be traced to human causes.” While the first of these choices is stated in the first paragraph and the second is stated in the second paragraph, neither relates to the other paragraph, or even adequately summarizes the entire paragraph in which it appears. This leaves us with one answer choice, the correct one: “Flightless birds sometimes develop strong running abilities, but if they don’t, they may be threatened with extinction.” Each of the two paragraphs can relate to this answer choice, but it doesn’t include things that the passage doesn’t discuss.
When asked to identify a passage’s main idea, it is important to pick out an answer choice to which all of the paragraphs can relate, but that is not too broad in including things that the passage does not discuss. Considering if each of the answer choices falls into one or another of these categories can help you narrow down your choices. For instance, “Birds employ a variety of defenses for avoiding predators” is far too broad to accurately describer this passage’s main idea. The author only discusses flightless birds, not all birds. “Flightless birds adapt to their particular surroundings” cannot be correct either, as the first paragraph discusses this, but the second paragraph discusses a flightless bird that did not adapt to its surroundings. Since the second paragraph can’t relate to this answer, it can’t be the main idea of the entire passage. Two of the remaining answer choices can be discarded due to their being too detailed: “The African ostrich’s strong leg muscles makes it well adapted to its environment” and “The extinction of the dodo can be traced to human causes.” While the first of these choices is stated in the first paragraph and the second is stated in the second paragraph, neither relates to the other paragraph, or even adequately summarizes the entire paragraph in which it appears. This leaves us with one answer choice, the correct one: “Flightless birds sometimes develop strong running abilities, but if they don’t, they may be threatened with extinction.” Each of the two paragraphs can relate to this answer choice, but it doesn’t include things that the passage doesn’t discuss.
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Adapted from On the Origin of Species by Charles Darwin (1859)
How will the struggle for existence, discussed too briefly in the last chapter, act in regard to variation? Can the principle of selection, which we have seen is so potent in the hands of man, apply in nature? I think we shall see that it can act most effectually. Let it be borne in mind in what an endless number of strange peculiarities our domestic productions, and, in a lesser degree, those under nature, vary; and how strong the hereditary tendency is. Under domestication, it may be truly said that the whole organization becomes in some degree plastic. Let it be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life. Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations? If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind? On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed. This preservation of favorable variations and the rejection of injurious variations, I call Natural Selection. Variations neither useful nor injurious would not be affected by natural selection, and would be left a fluctuating element, as perhaps we see in the species called polymorphic.
We shall best understand the probable course of natural selection by taking the case of a country undergoing some physical change, for instance, of climate. The proportional numbers of its inhabitants would almost immediately undergo a change, and some species might become extinct. We may conclude, from what we have seen of the intimate and complex manner in which the inhabitants of each country are bound together, that any change in the numerical proportions of some of the inhabitants, independently of the change of climate itself, would most seriously affect many of the others. If the country were open on its borders, new forms would certainly immigrate, and this also would seriously disturb the relations of some of the former inhabitants. Let it be remembered how powerful the influence of a single introduced tree or mammal has been shown to be. But in the case of an island, or of a country partly surrounded by barriers, into which new and better adapted forms could not freely enter, we should then have places in the economy of nature which would assuredly be better filled up, if some of the original inhabitants were in some manner modified; for, had the area been open to immigration, these same places would have been seized on by intruders. In such case, every slight modification, which in the course of ages chanced to arise, and which in any way favoured the individuals of any of the species, by better adapting them to their altered conditions, would tend to be preserved; and natural selection would thus have free scope for the work of improvement.
The main topic of this passage is .
Adapted from On the Origin of Species by Charles Darwin (1859)
How will the struggle for existence, discussed too briefly in the last chapter, act in regard to variation? Can the principle of selection, which we have seen is so potent in the hands of man, apply in nature? I think we shall see that it can act most effectually. Let it be borne in mind in what an endless number of strange peculiarities our domestic productions, and, in a lesser degree, those under nature, vary; and how strong the hereditary tendency is. Under domestication, it may be truly said that the whole organization becomes in some degree plastic. Let it be borne in mind how infinitely complex and close-fitting are the mutual relations of all organic beings to each other and to their physical conditions of life. Can it, then, be thought improbable, seeing that variations useful to man have undoubtedly occurred, that other variations useful in some way to each being in the great and complex battle of life, should sometimes occur in the course of thousands of generations? If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind? On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed. This preservation of favorable variations and the rejection of injurious variations, I call Natural Selection. Variations neither useful nor injurious would not be affected by natural selection, and would be left a fluctuating element, as perhaps we see in the species called polymorphic.
We shall best understand the probable course of natural selection by taking the case of a country undergoing some physical change, for instance, of climate. The proportional numbers of its inhabitants would almost immediately undergo a change, and some species might become extinct. We may conclude, from what we have seen of the intimate and complex manner in which the inhabitants of each country are bound together, that any change in the numerical proportions of some of the inhabitants, independently of the change of climate itself, would most seriously affect many of the others. If the country were open on its borders, new forms would certainly immigrate, and this also would seriously disturb the relations of some of the former inhabitants. Let it be remembered how powerful the influence of a single introduced tree or mammal has been shown to be. But in the case of an island, or of a country partly surrounded by barriers, into which new and better adapted forms could not freely enter, we should then have places in the economy of nature which would assuredly be better filled up, if some of the original inhabitants were in some manner modified; for, had the area been open to immigration, these same places would have been seized on by intruders. In such case, every slight modification, which in the course of ages chanced to arise, and which in any way favoured the individuals of any of the species, by better adapting them to their altered conditions, would tend to be preserved; and natural selection would thus have free scope for the work of improvement.
The main topic of this passage is .
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The passage seems focused on science and the progression of species over time. The language has mostly to do with "organic beings" and their evolution over time.
The passage seems focused on science and the progression of species over time. The language has mostly to do with "organic beings" and their evolution over time.
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Adapted from The Evolutionist at Large by Grant Allen (1881)
I am engaged in watching a brigade of ants out on foraging duty, and intent on securing for the nest three whole segments of a deceased earthworm. They look for all the world like those busy companies one sees in the Egyptian wall paintings, dragging home a huge granite colossus by sheer force of bone and sinew. Every muscle in their tiny bodies is strained to the utmost as they pry themselves laboriously against the great boulders that strew the path, and that are known to our Brobdingnagian intelligence as grains of sand. Besides the workers themselves, a whole battalion of stragglers runs to and fro upon the broad line that leads to the headquarters of the community. The province of these stragglers, who seem so busy doing nothing, probably consists in keeping communications open, and encouraging the sturdy pullers by occasional relays of fresh workmen. I often wish that I could for a while get inside those tiny brains, and see, or rather smell, the world as ants do. For there can be little doubt that to these brave little carnivores here the universe is chiefly known as a collective bundle of odors, simultaneous or consecutive. As our world is mainly a world of visible objects, theirs, I believe, is mainly a world of olfactible things.
In the head of every one of these little creatures is something that we may fairly call a brain. Of course most insects have no real brains; the nerve-substance in their heads is a mere collection of ill-arranged ganglia, directly connected with their organs of sense. Whatever man may be, an earwig at least is a conscious, or rather a semi-conscious, automaton. He has just a few knots of nerve cells in his little pate, each of which leads straight from his dim eye or his vague ear or his indefinite organs of taste; and his muscles obey the promptings of external sensations without possibility of hesitation or consideration, as mechanically as the valve of a steam engine obeys the governor balls. The poor soul's intellect is wholly deficient, and the senses alone make up all that there is of him, subjectively considered. But it is not so with the highest insects. They have something that truly answers to the real brain of men, apes, and dogs, to the cerebral hemispheres and the cerebellum that are superadded in us mammals upon the simple sense-centers of lower creatures. Besides the eye, with its optic nerve and optic perceptive organs—besides the ear, with its similar mechanism—we mammalian lords of creation have a higher and more genuine brain, that collects and compares the information given to the senses, and sends down the appropriate messages to the muscles accordingly. Now, bees and flies and ants have got much the same sort of arrangement, on a smaller scale, within their tiny heads. On top of the little knots that do duty as nerve centers for their eyes and mouths, stand two stalked bits of nervous matter, whose duty is analogous to that of our own brains. And that is why these three sorts of insects think and reason so much more intellectually than beetles or butterflies, and why the larger part of them have organized their domestic arrangements on such an excellent cooperative plan.
We know well enough what forms the main material of thought with bees and flies, and that is visible objects. For you must think about something if you think at all; and you can hardly imagine a contemplative blow-fly setting itself down to reflect, like a Hindu devotee, on the syllable Om, or on the oneness of existence. Abstract ideas are not likely to play a large part in apian consciousness. A bee has a very perfect eye, and with this eye it can see not only form, but also color, as Sir John Lubbock's experiments have shown us. The information that it gets through its eye, coupled with other ideas derived from touch, smell, and taste, no doubt makes up the main thinkable and knowable universe as it reveals itself to the apian intelligence. To ourselves and to bees alike the world is, on the whole, a colored picture, with the notions of distance and solidity thrown in by touch and muscular effort; but sight undoubtedly plays the first part in forming our total conception of things generally.
What is the main idea of the first paragraph?
Adapted from The Evolutionist at Large by Grant Allen (1881)
I am engaged in watching a brigade of ants out on foraging duty, and intent on securing for the nest three whole segments of a deceased earthworm. They look for all the world like those busy companies one sees in the Egyptian wall paintings, dragging home a huge granite colossus by sheer force of bone and sinew. Every muscle in their tiny bodies is strained to the utmost as they pry themselves laboriously against the great boulders that strew the path, and that are known to our Brobdingnagian intelligence as grains of sand. Besides the workers themselves, a whole battalion of stragglers runs to and fro upon the broad line that leads to the headquarters of the community. The province of these stragglers, who seem so busy doing nothing, probably consists in keeping communications open, and encouraging the sturdy pullers by occasional relays of fresh workmen. I often wish that I could for a while get inside those tiny brains, and see, or rather smell, the world as ants do. For there can be little doubt that to these brave little carnivores here the universe is chiefly known as a collective bundle of odors, simultaneous or consecutive. As our world is mainly a world of visible objects, theirs, I believe, is mainly a world of olfactible things.
In the head of every one of these little creatures is something that we may fairly call a brain. Of course most insects have no real brains; the nerve-substance in their heads is a mere collection of ill-arranged ganglia, directly connected with their organs of sense. Whatever man may be, an earwig at least is a conscious, or rather a semi-conscious, automaton. He has just a few knots of nerve cells in his little pate, each of which leads straight from his dim eye or his vague ear or his indefinite organs of taste; and his muscles obey the promptings of external sensations without possibility of hesitation or consideration, as mechanically as the valve of a steam engine obeys the governor balls. The poor soul's intellect is wholly deficient, and the senses alone make up all that there is of him, subjectively considered. But it is not so with the highest insects. They have something that truly answers to the real brain of men, apes, and dogs, to the cerebral hemispheres and the cerebellum that are superadded in us mammals upon the simple sense-centers of lower creatures. Besides the eye, with its optic nerve and optic perceptive organs—besides the ear, with its similar mechanism—we mammalian lords of creation have a higher and more genuine brain, that collects and compares the information given to the senses, and sends down the appropriate messages to the muscles accordingly. Now, bees and flies and ants have got much the same sort of arrangement, on a smaller scale, within their tiny heads. On top of the little knots that do duty as nerve centers for their eyes and mouths, stand two stalked bits of nervous matter, whose duty is analogous to that of our own brains. And that is why these three sorts of insects think and reason so much more intellectually than beetles or butterflies, and why the larger part of them have organized their domestic arrangements on such an excellent cooperative plan.
We know well enough what forms the main material of thought with bees and flies, and that is visible objects. For you must think about something if you think at all; and you can hardly imagine a contemplative blow-fly setting itself down to reflect, like a Hindu devotee, on the syllable Om, or on the oneness of existence. Abstract ideas are not likely to play a large part in apian consciousness. A bee has a very perfect eye, and with this eye it can see not only form, but also color, as Sir John Lubbock's experiments have shown us. The information that it gets through its eye, coupled with other ideas derived from touch, smell, and taste, no doubt makes up the main thinkable and knowable universe as it reveals itself to the apian intelligence. To ourselves and to bees alike the world is, on the whole, a colored picture, with the notions of distance and solidity thrown in by touch and muscular effort; but sight undoubtedly plays the first part in forming our total conception of things generally.
What is the main idea of the first paragraph?
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The paragraph as a whole describes a scene where the author is watching ants. This leads naturally into a discussion of how they may perceive the world, particularly through their sense of smell. Although the author does wish to have a heightened sense of smell and also compares the ants to events in history, these things do not encompass the entire paragraph.
The paragraph as a whole describes a scene where the author is watching ants. This leads naturally into a discussion of how they may perceive the world, particularly through their sense of smell. Although the author does wish to have a heightened sense of smell and also compares the ants to events in history, these things do not encompass the entire paragraph.
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