This preview shows page 1. Sign up to view the full content.
Unformatted text preview: ecologist Glen MacDonald's argument that the original migration occurred much later than had previously been believed ○the demonstration that certain previously accepted radiocarbon dates were incorrect
○evidence that the continental ice began its final retreat much later than had previously been believed
○research showing that the icefree corridor was not as long lasting as had been widely assumed
2. The word persuasively in the passage is closest in meaning to ○aggressively
Paragraph 2: Support is growing for the alternative theory that people using watercraft, possibly skin boats, moved southward from Beringia along the Gulf of Alaska and then southward along the Northwest Coast of North America possibly as early as 16,000 years ago. This route would have enabled humans to enter southern areas of the Americans prior to the melting of the continental glaciers. Until the early 1970s, most archaeologists did not consider the coast a possible migration route into the Americans because geologists originally believed that during the last Ice Age the entire Northwest Coast was covered by glacial ice. It had been assumed that the ice extended westward from the Alaskan/Canadian mountains to the very edge of the continental shelf, the flat, submerged part of the continent that extend into the ocean. This would have created a barrier of ice extending from the Alaska Peninsula, through the Gulf of Alaska and southward along the Northwest Coast of North America to what is today the state of Washington.
3. Paragraph 2 begins by presenting a theory and then goes on to 265
Mail@liuwenyong.com 在在在在在在 www.liuwenyong.com 在在在在在在在在在在在在在在在,在在在在在在在在在在
○discuss why the theory was rapidly accepted but then rejected ○present the evidence on which the theory was based
○cite evidence that now shows that the theory is incorrect
○explain why the theory was not initially considered plausible
4. The phrase prior to is closest in meaning to ○before
○in spite of 5. Paragraph 2 supports the idea that, before the 1970s, the most archaeologists held which of the following views about the earliest people to reach the Americas? ○They could not have sailed directly from Beringia to Alaska and then southward because, it was thought, glacial ice covered the entire coastal region. ○They were not aware that the climate would continue to become milder
○They would have had no interest in migrating southward from Beringia until after the continental glaciers had begun to melt ○They lacked the navigational skills and appropriate boats needed longdistance trips.
Paragraph 3: The most influential proponent of the coastal migration route has been Canadian archaeologist Knut Fladmark. He theorized that with the use of watercraft, people gradually colonized unglaciated refuges and areas along the continental shelf exposed by the lower sea level. Fladmark's hypothesis received addi...
View Full Document
- Fall '13