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Question based on the following passage.
This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.
This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.
Anyone watching the autumn sky knows that
migrating birds fly in a V formation, but scientists
have long debated why. A new study of ibises finds
that these big-winged birds carefully position their
(5) wingtips and sync their flapping, presumably to catch
the preceding bird’s updraft—and save energy
during flight.
There are two reasons birds might fly in a
V formation: It may make flight easier, or they’re
(10) simply following the leader. Squadrons of planes can
save fuel by flying in a V formation, and many
scientists suspect that migrating birds do the same.
Models that treated flapping birds like fixed-wing
airplanes estimate that they save energy by drafting
(15) off each other, but currents created by airplanes are
far more stable than the oscillating eddies coming off
of a bird. “Air gets pretty unpredictable behind a
flapping wing,” says James Usherwood, a locomotor
biomechanist at the Royal Veterinary College at the
(20) University of London in Hatfield, where the research
took place.
The study, published in Nature, took advantage of
an existing project to reintroduce endangered
northern bald ibises (Geronticus eremita) to Europe.
(25) Scientists used a microlight plane to show
hand-raised birds their ancestral migration route
from Austria to Italy. A flock of 14 juveniles carried
data loggers specially built by Usherwood and his lab.
The device’s GPS determined each bird’s flight
(30) position to within 30 cm, and an accelerometer
showed the timing of the wing flaps.
Just as aerodynamic estimates would predict, the
birds positioned themselves to fly just behind and to
the side of the bird in front, timing their wing beats
(35) to catch the uplifting eddies. When a bird flew
directly behind another, the timing of the flapping
reversed so that it could minimize the effects of the
downdraft coming off the back of the bird’s body.
“We didn’t think this was possible,” Usherwood
(40) says, considering that the feat requires careful
flight and incredible awareness of one’s neighbors.
“Perhaps these big V formation birds can be thought
of quite like an airplane with wings that go up and
down.”
(45) The findings likely apply to other long-winged
birds, such as pelicans, storks, and geese, Usherwood
says. Smaller birds create more complex wakes that
would make drafting too difficult. The researchers
did not attempt to calculate the bird’s energy savings
(50) because the necessary physiological measurements
would be too invasive for an endangered species.
Previous studies estimate that birds can use
20 percent to 30 percent less energy while
flying in a V.
(55) “From a behavioral perspective it’s really a
breakthrough,” says David Lentink, a mechanical
engineer at Stanford University in Palo Alto,
California, who was not involved in the work.
“Showing that birds care about syncing their wing
(60) beats is definitely an important insight that we didn’t
have before.”
Scientists do not know how the birds find
that aerodynamic sweet spot, but they suspect that
the animals align themselves either by sight or
(65) by sensing air currents through their feathers.
Alternatively, they may move around until they find
the location with the least resistance. In future
studies, the researchers will switch to more common
birds, such as pigeons or geese. They plan to
(70) investigate how the animals decide who sets the
course and the pace, and whether a mistake made by
the leader can ripple through the rest of the flock to
cause traffic jams.
“It’s a pretty impressive piece of work as it is, but
(75) it does suggest that there’s a lot more to learn,”
says Ty Hedrick, a biologist at the University of
North Carolina, Chapel Hill, who studies flight
aerodynamics in birds and insects. However they do
it, he says, “birds are awfully good hang-glider
(80) pilots.
migrating birds fly in a V formation, but scientists
have long debated why. A new study of ibises finds
that these big-winged birds carefully position their
(5) wingtips and sync their flapping, presumably to catch
the preceding bird’s updraft—and save energy
during flight.
There are two reasons birds might fly in a
V formation: It may make flight easier, or they’re
(10) simply following the leader. Squadrons of planes can
save fuel by flying in a V formation, and many
scientists suspect that migrating birds do the same.
Models that treated flapping birds like fixed-wing
airplanes estimate that they save energy by drafting
(15) off each other, but currents created by airplanes are
far more stable than the oscillating eddies coming off
of a bird. “Air gets pretty unpredictable behind a
flapping wing,” says James Usherwood, a locomotor
biomechanist at the Royal Veterinary College at the
(20) University of London in Hatfield, where the research
took place.
The study, published in Nature, took advantage of
an existing project to reintroduce endangered
northern bald ibises (Geronticus eremita) to Europe.
(25) Scientists used a microlight plane to show
hand-raised birds their ancestral migration route
from Austria to Italy. A flock of 14 juveniles carried
data loggers specially built by Usherwood and his lab.
The device’s GPS determined each bird’s flight
(30) position to within 30 cm, and an accelerometer
showed the timing of the wing flaps.
Just as aerodynamic estimates would predict, the
birds positioned themselves to fly just behind and to
the side of the bird in front, timing their wing beats
(35) to catch the uplifting eddies. When a bird flew
directly behind another, the timing of the flapping
reversed so that it could minimize the effects of the
downdraft coming off the back of the bird’s body.
“We didn’t think this was possible,” Usherwood
(40) says, considering that the feat requires careful
flight and incredible awareness of one’s neighbors.
“Perhaps these big V formation birds can be thought
of quite like an airplane with wings that go up and
down.”
(45) The findings likely apply to other long-winged
birds, such as pelicans, storks, and geese, Usherwood
says. Smaller birds create more complex wakes that
would make drafting too difficult. The researchers
did not attempt to calculate the bird’s energy savings
(50) because the necessary physiological measurements
would be too invasive for an endangered species.
Previous studies estimate that birds can use
20 percent to 30 percent less energy while
flying in a V.
(55) “From a behavioral perspective it’s really a
breakthrough,” says David Lentink, a mechanical
engineer at Stanford University in Palo Alto,
California, who was not involved in the work.
“Showing that birds care about syncing their wing
(60) beats is definitely an important insight that we didn’t
have before.”
Scientists do not know how the birds find
that aerodynamic sweet spot, but they suspect that
the animals align themselves either by sight or
(65) by sensing air currents through their feathers.
Alternatively, they may move around until they find
the location with the least resistance. In future
studies, the researchers will switch to more common
birds, such as pigeons or geese. They plan to
(70) investigate how the animals decide who sets the
course and the pace, and whether a mistake made by
the leader can ripple through the rest of the flock to
cause traffic jams.
“It’s a pretty impressive piece of work as it is, but
(75) it does suggest that there’s a lot more to learn,”
says Ty Hedrick, a biologist at the University of
North Carolina, Chapel Hill, who studies flight
aerodynamics in birds and insects. However they do
it, he says, “birds are awfully good hang-glider
(80) pilots.
Q. What is a main idea of the seventh paragraph (lines 62-73)?
- a)Different types of hierarchies exist in each flock of birds.
- b)Mistakes can happen when long-winged birds create a V formation.
- c)Future research will help scientists to better understand V formations.
- d)Long-winged birds watch the lead bird closely to keep a V formation intact.
Correct answer is option 'C'. Can you explain this answer?
Most Upvoted Answer
Question based on the following passage.This passage is adapted from P...
Choice C is the best answer. The seventh paragraph speculates that further research may provide insight into how and why birds fly in formation: “In future studies, the researchers will switch to more common birds, such as pigeons or geese. They plan to investigate how the animals decide who sets the course and the pace.” In sum, the seventh paragraph can therefore be seen as recognizing that more research is needed to explain the phenomenon of flight formation more completely.
Choice A is incorrect because neither the seventh paragraph nor the passage as a whole is concerned with bird hierarchies; the decision as to which bird sets the “course” or “pace” is mentioned only as another aspect of bird flight that scientists have yet to explain fully. Choice B is incorrect because the seventh paragraph only briefly mentions mistakes in V-formation flight, and this subject is not a central focus of the paragraph. Choice D is incorrect because although the seventh paragraph mentions the sighting of a lead bird or “leader” as a possible factor in the V formation, this factor is mentioned briefly and in conjunction with other factors, so that to describe it as a main idea would misrepresent the paragraph as a whole.
Choice A is incorrect because neither the seventh paragraph nor the passage as a whole is concerned with bird hierarchies; the decision as to which bird sets the “course” or “pace” is mentioned only as another aspect of bird flight that scientists have yet to explain fully. Choice B is incorrect because the seventh paragraph only briefly mentions mistakes in V-formation flight, and this subject is not a central focus of the paragraph. Choice D is incorrect because although the seventh paragraph mentions the sighting of a lead bird or “leader” as a possible factor in the V formation, this factor is mentioned briefly and in conjunction with other factors, so that to describe it as a main idea would misrepresent the paragraph as a whole.
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Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer?
Question Description
Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? for SAT 2025 is part of SAT preparation. The Question and answers have been prepared according to the SAT exam syllabus. Information about Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for SAT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer?.
Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? for SAT 2025 is part of SAT preparation. The Question and answers have been prepared according to the SAT exam syllabus. Information about Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for SAT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer?.
Solutions for Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for SAT.
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Here you can find the meaning of Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer?, a detailed solution for Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? has been provided alongside types of Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Question based on the following passage.This passage is adapted from Patricia Waldron, “Why Birds Fly in a V Formation.” ©2014 by American Association for the Advancement of Science.Anyone watching the autumn sky knows thatmigrating birds fly in a V formation, but scientistshave long debated why. A new study of ibises findsthat these big-winged birds carefully position their(5) wingtips and sync their flapping, presumably to catchthe preceding bird’s updraft—and save energyduring flight.There are two reasons birds might fly in aV formation: It may make flight easier, or they’re(10) simply following the leader. Squadrons of planes cansave fuel by flying in a V formation, and manyscientists suspect that migrating birds do the same.Models that treated flapping birds like fixed-wingairplanes estimate that they save energy by drafting(15) off each other, but currents created by airplanes arefar more stable than the oscillating eddies coming offof a bird. “Air gets pretty unpredictable behind aflapping wing,” says James Usherwood, a locomotorbiomechanist at the Royal Veterinary College at the(20) University of London in Hatfield, where the researchtook place.The study, published in Nature, took advantage ofan existing project to reintroduce endangerednorthern bald ibises (Geronticus eremita) to Europe.(25) Scientists used a microlight plane to showhand-raised birds their ancestral migration routefrom Austria to Italy. A flock of 14 juveniles carrieddata loggers specially built by Usherwood and his lab.The device’s GPS determined each bird’s flight(30) position to within 30 cm, and an accelerometershowed the timing of the wing flaps.Just as aerodynamic estimates would predict, thebirds positioned themselves to fly just behind and tothe side of the bird in front, timing their wing beats(35) to catch the uplifting eddies. When a bird flewdirectly behind another, the timing of the flappingreversed so that it could minimize the effects of thedowndraft coming off the back of the bird’s body.“We didn’t think this was possible,” Usherwood(40) says, considering that the feat requires carefulflight and incredible awareness of one’s neighbors.“Perhaps these big V formation birds can be thoughtof quite like an airplane with wings that go up anddown.”(45) The findings likely apply to other long-wingedbirds, such as pelicans, storks, and geese, Usherwoodsays. Smaller birds create more complex wakes thatwould make drafting too difficult. The researchersdid not attempt to calculate the bird’s energy savings(50) because the necessary physiological measurementswould be too invasive for an endangered species.Previous studies estimate that birds can use20 percent to 30 percent less energy whileflying in a V.(55) “From a behavioral perspective it’s really abreakthrough,” says David Lentink, a mechanicalengineer at Stanford University in Palo Alto,California, who was not involved in the work.“Showing that birds care about syncing their wing(60) beats is definitely an important insight that we didn’thave before.”Scientists do not know how the birds findthat aerodynamic sweet spot, but they suspect thatthe animals align themselves either by sight or(65) by sensing air currents through their feathers.Alternatively, they may move around until they findthe location with the least resistance. In futurestudies, the researchers will switch to more commonbirds, such as pigeons or geese. They plan to(70) investigate how the animals decide who sets thecourse and the pace, and whether a mistake made bythe leader can ripple through the rest of the flock tocause traffic jams.“It’s a pretty impressive piece of work as it is, but(75) it does suggest that there’s a lot more to learn,”says Ty Hedrick, a biologist at the University ofNorth Carolina, Chapel Hill, who studies flightaerodynamics in birds and insects. However they doit, he says, “birds are awfully good hang-glider(80) pilots.Q.What is a main idea of the seventh paragraph (lines 62-73)?a)Different types of hierarchies exist in each flock of birds.b)Mistakes can happen when long-winged birds create a V formation.c)Future research will help scientists to better understand V formations.d)Long-winged birds watch the lead bird closely to keep a V formation intact.Correct answer is option 'C'. Can you explain this answer? tests, examples and also practice SAT tests.
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