2. 外语
  3. The last of the dinosaurs lived during a time called the Cretaceous period. This time period lasted from about 135 million to 65

The last of the dinosaurs lived during a time called the Cretaceous period. This time period lasted from about 135 million to 65

admin2014-01-13  34
问题     The last of the dinosaurs lived during a time called the Cretaceous period. This time period lasted from about 135 million to 65.5 million years ago. Some sources give the years of 146,145, or 144 million to 65 million years ago.
    In the Cretaceous period, the middle of North America was covered by a shallow sea. The Atlantic Ocean began opening up between Europe and North America as those continents rifted. Other continents that had begun pulling away from each other in the Jurassic continued drifting apart. India was an island by itself.
    Evergreen trees, mosses, and ferns had been the main types of plants, but now in the Cretaceous, flowering plants appeared. Bees did, too. Hardwood trees like oaks and maples first appeared in the fossil record.
    Modem birds and mammals came into the fossil record. Tyrannosaurus and Triceratops came into existence. So did other ceratopsian dinosaurs, relatives of Triceratops, with their wide variety of facial horns and neck frills. Great herds of perhaps 10,000 Triceratops roamed the edges of the North American Inland Sea. The climate began to cool.
    At the end of the Cretaceous, another mass extinction wiped out as much as 90 percent of marine life and 50 percent of life on land. There were no more dinosaurs after the end of the Cretaceous, at about 65.5 million years ago. The Cenozoic era, also called the Age of Mammals, began.
Continents in the Cretaceous period were______.
选项 A、drifting apart
B、moving towards each other
C、in the same locations as they are today
D、none of the above
答案A
解析 根据文中第二段的“In the Cretaceous period，…as those continents tiffed．Othercontinents that had begun pulling away from each other in the Jurassic continued drifting apart．”可知，在白垩纪时期，这些大陆分裂开了。其他在侏罗纪开始裂开的大陆继续漂移。据此可知，A项正确。
转载请注明原文地址:https://kaotiyun.com/show/a6QO777K
0

考博英语

相关试题推荐
随机试题
最新回复(0)