章节大纲

  • What you will learn
    ::你会学到什么

    • Why Mesozoic era was the age of dinosaurs
      ::为什么美索索分裂时代是恐龙时代
    • The three periods of the Mesozoic Era: the Triassic, the Jurassic, and the Cretaceous
      ::3个时期,即三思西奇、侏罗西奇和白鲸。
    • What caused the extinction of dinosaurs
      ::导致恐龙灭绝的原因

    Two green dinosaurs wade through shallow waters, heading toward vegetation on an island.

    What exactly is a dinosaur?
    ::什么是恐龙?

    Two dinosaurs wade through shallow waters to get to the vegetation on this island. The Mesozoic Era is the age of dinosaurs. These grew so large they dominated the planet. Dinosaurs were so dominant that it took a catastrophic, environment-changing event for mammals to be able to take over.
    ::两只恐龙在浅水中漫步,到达岛上的植被。 中索索伊克时代是恐龙时代, 这些恐龙长大了如此之大, 主宰了地球。恐龙占据了主导地位, 以至于哺乳动物们不得不承受一场灾难性的环境变化事件才能接管。

    Mesozoic Era: The Age of Dinosaurs
    ::Mesozoic时代:恐龙时代

    The Mesozoic Era is literally the era of “middle life.” It is also known as the age of dinosaurs . It lasted from 252 to 66 million years ago and is divided into three periods. The Mesozoic began with the supercontinent Pangaea . Then, during the era, Pangaea broke up and the continents drifted apart. The movement of continents changed climates. It also caused tremendous volcanic activity.
    ::中祖时代实际上就是“中世纪”的时代。 它也被称为恐龙时代,从252万年前的252万到6600万年前的6600万年,分为三个时期。中祖时代从超大陆潘加亚开始。然后,在这个时代,潘加亚解体,大陆四分五裂。大陆运动改变了气候。它也引发了巨大的火山活动。

    occurred at the end of the Triassic and Cretaceous Periods. The first extinction paved the way for a dinosaur takeover. In the second extinction, the dinosaurs finally disappeared.
    ::第一次灭绝为恐龙的接管铺平了道路。第二次灭绝,恐龙最终消失了。

    • Two dinosaurs in a prehistoric landscape with mountains and a river.
      Triassic Period (252–201 million years ago)

      ::三assic时期(252至201亿年前)
    • Dinosaurs in a prehistoric landscape with trees and flowers, depicting the Mesozoic Era.
      Jurassic Period (201–145 million years ago)

      ::侏罗纪时期(201-1.45亿年前)
    • A cartoon depiction of a Tyrannosaurus rex in a prehistoric landscape with forests and mountains.
      Cretaceous Period (145–66 million years ago)

      ::白鲸期(1.45亿至6.6亿年前)

    The Triassic Period  ( Figure ): During the Triassic Period (252–201 million years ago), the first dinosaurs branched off from the and colonized the land, while pterosaurs took to the skies and reptiles swam the seas. Huge seed and conifers dominated the forests, and modern corals, , and evolved. The supercontinent Pangaea started to separate into Laurasia (today’s Northern Hemisphere continents) and Gondwanaland (today’s Southern Hemisphere continents). The Triassic Period ended with a mass extinction.
    ::三亚西克时期(图 ) : 在三亚西克时期(252 - 201亿年前 ) , 第一批恐龙从这片土地上分离出来并殖民化了这片土地,而野生龙则登上天空,爬行动物席卷大海。 巨大的种子和锥虫主宰着森林和现代珊瑚,并演化了。 超级大陆庞加亚开始分裂成劳拉西亚(当今的北半球大陆 ) 和贡德瓦纳兰(今天的南半球大陆 ) 。 三亚西克时期以大规模灭绝告终。

    The Jurassic Period ( Figure ): The next period, the Jurassic Period (201–145 million years ago), began after the mass extinction that ended the Triassic Period. This mass extinction allowed dinosaurs to flourish in the Jurassic Period. This was the golden age of dinosaurs. Also during the Jurassic, the earliest evolved from reptile ancestors , and all the major groups of mammals evolved, though individual mammals were still small in size.  The first flowering plants probably evolved in the Jurassic, but ferns and conifers still dominated.   The continents continued to move apart, and volcanic activity was especially intense.
    ::侏罗纪时期(图 ) : 下个时期,即侏罗纪时期(201-1.45亿年前 ) , 始于结束三亚纪时期的大规模灭绝之后。 这种大规模灭绝让恐龙在侏罗纪时期蓬勃发展。 这是恐龙的黄金时代。 在侏罗纪时期,最早从爬行动物祖先演变而来,所有主要哺乳动物群体都在进化,尽管个别哺乳动物的规模仍然很小。 第一批开花植物可能在侏罗纪时期发展,但野生植物和锥虫仍然占据着主导地位。 大陆继续四分五裂,火山活动特别激烈。

    The Cretaceous Period ( Figure ): During the Cretaceous Period (145–66 million years ago), dinosaurs reached their peak in size and distribution.  Large dinosaurs of the period included predator Tyrannosaurus rex, which weighed at least 7 tons. By the end of the Cretaceous, the continents were close to their present locations. Earth’s overall climate was warm; even the poles lacked ice.  Flowering plants diversified, and new insects also evolved to pollinate the flowers .  The period ended with the dramatic extinction of most dinosaurs, except for those that led to birds.
    ::白龙时期(图示 ) : 在白龙时期(14.5亿到66亿年前 ) , 恐龙在规模和分布上达到了顶峰。 这一时期的大型恐龙包括至少重7吨的掠食性暴龙雷克斯。 在白龙时期结束时,各大洲与目前的位置相近。 地球的总体气候是温暖的,甚至极地也缺乏冰。 花岗岩的多样化,新的昆虫也演变为花卉的授粉。 这一时期随着大多数恐龙的大规模灭绝而结束,除了那些导致鸟类灭绝的恐龙。

    What happened to the dinosaurs? Why did they go extinct at the end of the Cretaceous Period? There is geologic evidence that an asteroid collided with Earth 66 million years ago.  Many scientists believe this collision was at least a contributing factor to the extinction, causing skies to darken, to shut down, and climates to change.  Without the dinosaurs, there were many opportunities for new organisms to exploit in the next era, the Cenozoic. Which living things do you think took over where the dinosaurs left off?
    ::恐龙到底怎么了?为什么它们会在白鲸期结束时灭绝?有地质证据表明6600万年前一颗小行星与地球相撞。许多科学家认为这次碰撞至少是导致灭绝的一个因素,它使天空变暗,关闭,气候发生变化。没有恐龙,新生物在下个时代就有许多机会去开发,即Cenozoic。你认为,在恐龙离开的地方,哪些生物会接管?

     

     

    Summary
    ::摘要

    • The Mesozoic Era is the age of dinosaurs and other reptiles.
      ::中祖时代是恐龙和其他爬行动物的时代。
    • They evolved to fill niches on land, in the water, and in the air. Mammals also evolved but were small in size.
      ::哺乳动物也在进化,但体积很小。
    • Flowering plants appeared for the first time.
      ::鲜花植物首次出现。
    • Dinosaurs went extinct at the end of the Mesozoic.
      ::恐龙在中索佐奇河末端灭绝了

    Review
    ::回顾

    1. Describe how the continents shifted during the Mesozoic Era.
      ::描述大陆在中西索契时代是如何变化的。
    2. Create a timeline of major evolutionary events during the Mesozoic Era.
      ::在中索佐伊克时代建立重大进化事件时间表。
    3. Explain why scientists believe dinosaurs went extinct.
      ::科学家们认为恐龙灭绝的原因