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PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are.  When  population density is high, only the strongest males can retain a suitable area.  The weakest males do not breed or are forced to nest on poor or marginal territories.
During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds.  These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency.  Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited.  Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis .  In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do.  Thus, it would seem that they copy their figures from other buntings they hear signing.
Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song.  When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond;  Even when a dummy of male indigo bunting was placed near the tape recorder.  Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.
The role of the songs figures in interspecies recognition was then examined.  We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features.  Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses.  It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.
There is evident that new figures may arise within a population through a slow process of change and selection.  This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger.  Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.
Q. It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily to
  • a)
    ensure species survival by increasing competition among the fittest males for the females
  • b)
    increase population density by eliminating ambiguity in the figures to which the females must respond
  • c)
    maintain the integrity of the species by restricting the degree of figure variation and change
  • d)
    enhance species recognition by decreasing the number of figure patterns to which the bird must respond
  • e)
    avoid confusion between species by clearly demarcating the figure patterns of each specials
Correct answer is option 'D'. Can you explain this answer?
Most Upvoted Answer
PASSAGE:In strongly territorial birds such as the indigo bunting, song...
- The limited number of indigo bunting figures primarily enhances species recognition by decreasing the variety of figure patterns the bird must respond to.
- This limitation ensures that each species has a distinct set of figures for clear-cut species recognition.
- By restricting the variation and change in figures, the integrity of the species is maintained.
- It allows for individual recognition within the species without causing confusion between different species.
- Ultimately, this balance between figure stability and variation aids in both species and individual recognition.
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Community Answer
PASSAGE:In strongly territorial birds such as the indigo bunting, song...
Explanation:

Restricting figure variation and change:
- The limited number of indigo bunting figures ensures species recognition by decreasing the number of figure patterns to which the bird must respond.
- This restriction helps maintain the integrity of the species by ensuring that the birds can readily distinguish their own species' songs from those of other species.

Enhancing species recognition:
- By having a small number of stable figures, the indigo buntings can easily recognize and respond to songs of their own species, as shown in the passage where they responded to an indigo bunting song but not to songs of other species.
- This enhances species recognition and allows for clear-cut differentiation between species.
Therefore, the existence of only a limited number of indigo bunting figures primarily serves to enhance species recognition by decreasing the number of figure patterns to which the bird must respond, ensuring clear-cut species identification and avoiding confusion between species.
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PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer?
Question Description
PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer? for GRE 2024 is part of GRE preparation. The Question and answers have been prepared according to the GRE exam syllabus. Information about PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer? covers all topics & solutions for GRE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer?.
Solutions for PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer? in English & in Hindi are available as part of our courses for GRE. Download more important topics, notes, lectures and mock test series for GRE Exam by signing up for free.
Here you can find the meaning of PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer?, a detailed solution for PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer? has been provided alongside types of PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice PASSAGE:In strongly territorial birds such as the indigo bunting, song is the main mechanism for securing g, defining, and defending an adequate breeding are. When population density is high, only the strongest males can retain a suitable area. The weakest males do not breed or are forced to nest on poor or marginal territories.During the breeding season, the male indigo bunting sings in his territory; each song lasts two or three seconds with a very short pause between songs, Melodic and rhythmic characteristics are produced by rapid changes in sound frequency and some regularity of silent periods between sounds. These modulated sounds form recognizable units, called figures, each of which is reproduced again and again with remarkable consistency. Despite the large frequency range of these sounds and the rapid frequency changes that the birds makes, the n umber of figures is very limited. Further, although we found some unique figures in different geographical populations, more than 90 percent of all Indigo bunting figures are extremely stable on the geographic basis . In our studies of isolated buntings we found that male indigo buntings are capable of singing many more types of figures than they usually do. Thus, it would seem that they copy their figures from other buntings they hear signing.Realizing that the ability to distinguish the songs of one species from those of another could be an important factor in the volition of the figures, we tested species recognition of a song. When we played a tape recording of a lazuli bunting or a painted bunting, male indigo bunting did not respond; Even when a dummy of male indigo bunting was placed near the tape recorder. Playing an indigo bunting song, however, usually brought an immediate response, making it clear that a male indigo bunting can readily distinguished songs of its own species from those of other species.The role of the songs figures in interspecies recognition was then examined. We created experimental songs composed of new figures by playing a normal song backwards, which changed the detailed forms of the figures without altering frequency ranges or gross temporal features. Since the male indigos gave almost a full response to the backward song, we concluded that a wide range of figures shapes can evoke positive responses. It seems likely, therefore, that a specific configuration is not essential for interspecies recognition, but it is clear that song figures must confirm to a particular frequency range, must be within narrow limits of duration, and must be spaced at particular intervals.There is evident that new figures may arise within a population through a slow process of change and selection. This variety is probably a valuable adaptation for survival: if every bird sang only a few types of figures, in dense woods or underbrush a female might have difficulty recognizing her mate’s song and a male might not be able to distinguished a neighbor from a stranger. Our studies led us to conclude that there must be a balance between song stability and conservatism, which lead to clear-cut species recognition, and song variation, which leads to individual recognition.Q.It can be inferred from the passage that the existence of only a limited number of indigo bunting figures servers primarily toa)ensure species survival by increasing competition among the fittest males for the femalesb)increase population density by eliminating ambiguity in the figures to which the females must respondc)maintain the integrity of the species by restricting the degree of figure variation and changed)enhance species recognition by decreasing the number of figure patterns to which the bird must responde)avoid confusion between species by clearly demarcating the figure patterns of each specialsCorrect answer is option 'D'. Can you explain this answer? tests, examples and also practice GRE tests.
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