How the First People Got to the Interior of North America
Most researchers believe that the first people to come to North America came from Asia to what is now Alaska across a land bridge called Beringia, which was exposed as a result of low sea levels during the lce Age. Evidence in the heart of North America points to a settlement time of around 14,000 years B.P. (before present). But there is some disagreement about which route these settlers took to the interior of a still uninhabited North America from Alaska. Until recently, everyone agreed that the first settlers traveled southward by land through the interior between two great ice sheets, the Cordilleran and the Laurentide; but in recent years, a growing number of people have favored the idea of a coastal route, triggering a major debate.
In the 1950s, Canadian geologists reported that Cordilleran ice did not fuse with the western margins of the Laurentide, creating between them an ice-free corridor sometimes called the Mackenzie Corridor. The Mackenzie Corridor became, in the minds of some, a kind of superhighway to the south, where mammoths and people traveled. This appealing picture is a geological myth, for the boundaries of the ice sheets are slowly being mapped, revealing only a partial corridor, and one that was very inhospitable indeed. With rugged land, mazes of meltwater lakes, crumbling rocks, the scantiest of vegetation, and few animals hunted for food, there was little incentive to travel through this ice-free zone at the height of the last Ice Age. If human beings did travel south, the most likely times for them to do so would have been either before the last glacial maximum (the period when ice sheets were at their maximum extension) beginning 25,000 years ago, or soon after 15,000 years ago, as the ice sheets began to retreat. Recent research has suggested that the corridor may have been quite wide by 11,000 years ago.
If the ice-free corridor was an inhospitable and late migration route to the south, what about other paths? Recent evidence suggests that long stretches of northern coastline from the Kuril Islands off Japan to Beringia and south through the Aleutians (a chain of volcanic islands in the northern Pacific Ocean) were more extensive 13,000 years ago than was once suspected. Did the Pacific coast provide a route into the heart of North America? Advocates of coastal settlement believe that fishing and sea mammal hunting, as well as a sophisticated maritime tradition, were well established in northeastern Asia during the late Ice Age, and that small groups of coastal people traversed the ice strewn shoreline of the Beringia land bridge, then hunted and fished their way southward through the fjords, bays, and more sheltered waterways of the Alaskan coast.
Such a theory is entirely plausible, but its advocates have to live with a reality that any sites likely to document such migrations are buried under 300 feet (90 meters) of rising seawater. Furthermore, there is absolutely no archaeological evidence for sophisticated sea mammal and maritime technology in the form of skin boats (umiaks)or skin kayaks in the far north before about 3000 years ago, when the Bering Strait region became a major center for sea mammal hunting. Maritime adaptations are considerably earlier along the Aleutian chain but certainly much later than a supposed, and perhaps conservative, crossing date of 14,000 years ago. No one has examined the difficulties that sailors would have encountered crossing from Siberia to Alaska in small crafts. Apart from ice flows and pack ice, both of which may have been thicker during a period of warming, the rowers would have had to develop the clothing and boats to deal with very cold water and hypothermia(low body temperature), as well as often savage weather conditions, even in midsummer.
The manual British Admiralty Ocean Passages for the World describes these waters in summer as wet, fog- ridden for days on end, and subject to frequent, severe westerly winds, conditions that challenge even today’s well-equipped fishing boats and freighters. Even in more southerly areas like southeastern Alaska, conditions can deteriorate rapidly, with strong headwinds that are notoriously difficult to row against. Southeast Alaska has plenty of sheltered bays and inlets, but the same cannot be said of the exposed coasts of the Gulf of Alaska, or of the shoreline south of Cape Flattery on the Olympic Peninsula, the Pacific route to lands far to the south.
1
Most researchers believe that the first people to come to North America came from Asia to what is now Alaska across a land bridge called Beringia, which was exposed as a result of low sea levels during the lce Age. Evidence in the heart of North America points to a settlement time of around 14,000 years B.P. (before present). But there is some disagreement about which route these settlers took to the interior of a still uninhabited North America from Alaska. Until recently, everyone agreed that the first settlers traveled southward by land through the interior between two great ice sheets, the Cordilleran and the Laurentide; but in recent years, a growing number of people have favored the idea of a coastal route, triggering a major debate.
Paragraph 1 indicates that a major debate among researchers has developed in recent years regarding which of the following ideas about the first people to arrive in North America?
AWhy they migrated to North America
BWhen they reached the heart of North America
CWhich route they took to the interior of North America
DWhich part of the world they migrated from
2
In the 1950s, Canadian geologists reported that Cordilleran ice did not fuse with the western margins of the Laurentide, creating between them an ice-free corridor sometimes called the Mackenzie Corridor. The Mackenzie Corridor became, in the minds of some, a kind of superhighway to the south, where mammoths and people traveled. This appealing picture is a geological myth, for the boundaries of the ice sheets are slowly being mapped, revealing only a partial corridor, and one that was very inhospitable indeed. With rugged land, mazes of meltwater lakes, crumbling rocks, the scantiest of vegetation, and few animals hunted for food, there was little incentive to travel through this ice-free zone at the height of the last Ice Age. If human beings did travel south, the most likely times for them to do so would have been either before the last glacial maximum (the period when ice sheets were at their maximum extension) beginning 25,000 years ago, or soon after 15,000 years ago, as the ice sheets began to retreat. Recent research has suggested that the corridor may have been quite wide by 11,000 years ago.
The word “appealing” in the passage is closest in meaning to
Adescriptive
Bsimplistic
Cattractive
Dmisleading
3
In the 1950s, Canadian geologists reported that Cordilleran ice did not fuse with the western margins of the Laurentide, creating between them an ice-free corridor sometimes called the Mackenzie Corridor. The Mackenzie Corridor became, in the minds of some, a kind of superhighway to the south, where mammoths and people traveled. This appealing picture is a geological myth, for the boundaries of the ice sheets are slowly being mapped, revealing only a partial corridor, and one that was very inhospitable indeed. With rugged land, mazes of meltwater lakes, crumbling rocks, the scantiest of vegetation, and few animals hunted for food, there was little incentive to travel through this ice-free zone at the height of the last Ice Age. If human beings did travel south, the most likely times for them to do so would have been either before the last glacial maximum (the period when ice sheets were at their maximum extension) beginning 25,000 years ago, or soon after 15,000 years ago, as the ice sheets began to retreat. Recent research has suggested that the corridor may have been quite wide by 11,000 years ago.
According to paragraph 2, what did geologists in the 1950s mistakenly believe about the Cordilleran and Laurentide ice sheets?
AHumans and mammoths were able to settle on the Cordilleran and Laurentide ice sheets.
BAn easily traveled corridor existed between the Cordilleran and Laurentide ice sheet
CThere was no vegetation in the area between the Cordilleran and Laurentide ice sheets
DThe Cordilleran and Laurentide ice sheets began to retreat 25,000 years ago
4
In the 1950s, Canadian geologists reported that Cordilleran ice did not fuse with the western margins of the Laurentide, creating between them an ice-free corridor sometimes called the Mackenzie Corridor. The Mackenzie Corridor became, in the minds of some, a kind of superhighway to the south, where mammoths and people traveled. This appealing picture is a geological myth, for the boundaries of the ice sheets are slowly being mapped, revealing only a partial corridor, and one that was very inhospitable indeed. With rugged land, mazes of meltwater lakes, crumbling rocks, the scantiest of vegetation, and few animals hunted for food, there was little incentive to travel through this ice-free zone at the height of the last Ice Age. If human beings did travel south, the most likely times for them to do so would have been either before the last glacial maximum (the period when ice sheets were at their maximum extension) beginning 25,000 years ago, or soon after 15,000 years ago, as the ice sheets began to retreat. Recent research has suggested that the corridor may have been quite wide by 11,000 years ago.
According to paragraph 2 which of the following is true of the last Ice Age?
AIt allowed human beings to move south over sheets of ice.
BIts ice sheets were largest between 25,000 years ago and about 15.000 years ago.
CIt caused ice sheets to continue growing until about 11.000 years ago.
DIts causes became known following recent research on the Mackenzie Corridor.
5
If the ice-free corridor was an inhospitable and late migration route to the south, what about other paths? Recent evidence suggests that long stretches of northern coastline from the Kuril Islands off Japan to Beringia and south through the Aleutians (a chain of volcanic islands in the northern Pacific Ocean) were more extensive 13,000 years ago than was once suspected. Did the Pacific coast provide a route into the heart of North America? Advocates of coastal settlement believe that fishing and sea mammal hunting, as well as a sophisticated maritime tradition, were well established in northeastern Asia during the late Ice Age, and that small groups of coastal people traversed the ice strewn shoreline of the Beringia land bridge, then hunted and fished their way southward through the fjords, bays, and more sheltered waterways of the Alaskan coast.
Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.
ASome argue that inhabitants of northeastern Asia had the necessary hunting, fishing, and sea travel skills to cross Beringia and migrate southward along the Alaskan coast.
BSome argue that inhabitants of northeast Asia introduced sea mammal hunting, as well as a sophisticated maritime tradition to coastal areas of North America
CSome argue that inhabitants of northeastern Asia had better- established more sophisticated maritime tradition than inhabitants of fords, bays, and waterways of Alaska
DSome argue that inhabitants of northeast Asia did not develop a sophisticated maritime tradition until the late Ice Age, when humans had already arrived in North America
6
Such a theory is entirely plausible, but its advocates have to live with a reality that any sites likely to document such migrations are buried under 300 feet (90 meters) of rising seawater. Furthermore, there is absolutely no archaeological evidence for sophisticated sea mammal and maritime technology in the form of skin boats (umiaks)or skin kayaks in the far north before about 3000 years ago, when the Bering Strait region became a major center for sea mammal hunting. Maritime adaptations are considerably earlier along the Aleutian chain but certainly much later than a supposed, and perhaps conservative, crossing date of 14,000 years ago. No one has examined the difficulties that sailors would have encountered crossing from Siberia to Alaska in small crafts. Apart from ice flows and pack ice, both of which may have been thicker during a period of warming, the rowers would have had to develop the clothing and boats to deal with very cold water and hypothermia(low body temperature), as well as often savage weather conditions, even in midsummer.
In paragraph 4. which of the following is NOT mentioned as a potential challenge to the theory of coastal migration route to North America?
ASailors would have had great difficulty dealing with very cold weather conditions, even in the summer
BSophisticated boats probably appeared in the far north only 3000 years ago
CThere was not yet a maritime tradition in the Aleutian chain at the supposed crossing time.
DThe Bering Sea had already risen by 90 meters at the time of the supposed crossing, making travel by simple skin boats impossible.
7
The manual British Admiralty Ocean Passages for the World describes these waters in summer as wet, fog- ridden for days on end, and subject to frequent, severe westerly winds, conditions that challenge even today’s well-equipped fishing boats and freighters. Even in more southerly areas like southeastern Alaska, conditions can deteriorate rapidly, with strong headwinds that are notoriously difficult to row against. Southeast Alaska has plenty of sheltered bays and inlets, but the same cannot be said of the exposed coasts of the Gulf of Alaska, or of the shoreline south of Cape Flattery on the Olympic Peninsula, the Pacific route to lands far to the south.
In paragraph 5, what is the author’s purpose in discussing information from the manual British Admirality Ocean Passages for the World?
ATo support the claim that the first humans migrated to North America in the summer rather than the winter
BTo imply that boats traveling along the coastline may have been pushed forward by wind rather than rowed
CTo suggest that sea conditions near southeastern Alaska have improved since humans first migrated to North America
DTo provide additional support for the idea that the route along the Alaskan coastline would have been extremely difficult for the early American settlers to traverse
8
Based on the information in the passage, which of the following best describes the author’s view about how the first people reached the interior of North America?
AThere are two plausible, competing theories, but both have weaknesses.
BA new theory has largely replaced two older, less plausible theories
CA theory put forward in the 1950s is still recognized as being the most plausible.
DNew evidence shows that each of he two proposed theories is partly but not fully correct
9
In the 1950s, Canadian geologists reported that Cordilleran ice did not fuse with the western margins of the Laurentide, creating between them an ice-free corridor sometimes called the Mackenzie Corridor. [■]The Mackenzie Corridor became, in the minds of some, a kind of superhighway to the south, where mammoths and people traveled. [■]This appealing picture is a geological myth, for the boundaries of the ice sheets are slowly being mapped, revealing only a partial corridor, and one that was very inhospitable indeed. [■]With rugged land, mazes of meltwater lakes, crumbling rocks, the scantiest of vegetation, and few animals hunted for food, there was little incentive to travel through this ice-free zone at the height of the last Ice Age. [■]If human beings did travel south, the most likely times for them to do so would have been either before the last glacial maximum (the period when ice sheets were at their maximum extension) beginning 25,000 years ago, or soon after 15,000 years ago, as the ice sheets began to retreat. Recent research has suggested that the corridor may have been quite wide by 11,000 years ago.
Look at the four squaresthat indicate where the following sentence could be added to the passage
This finding resulted in the theory that the first people to arrive in North America’s interior traveled south by land.
Where would the sentence best fit？Click on a square sentence to the passage.
10
This finding resulted in the theory that the first people to arrive in North America’s interior traveled south by land.
ARecent research suggests that the fusion of the Cordilleran and the Laurentide ice sheets formed a superhighway through which people and animals traveled
BThe coastline from Beringia through southeastern Alaska may have provided a possible migration route but any sites that could confirm this theory would now be under water.
CThe discovery of small boats from nearly 14,000 years ago demonstrated that an ocean migration from Siberia to North America was possible.
DThere was an ice free corridor leading to the interior of North America, but it would have been difficult to pass through until the ice sheets began to retreat 15.000 years ago.
ERough seas and cold weather would have made travel south down the Alaskan coastline difficult even if the settlers from northeastern Asia were experienced sea travelers
FThere are many inlets on the shore of the Gulf of Alaska and the Olympic Peninsula, providing support for a coastal migration route
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