文勇的新托福黄金&ccedil

thefieldof biological evolutionsuchimpacts

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Unformatted text preview: plicate prevent encourage affect Paragraph4: The Ediacara fossil formation, which contains the oldest known animal fossils, consists exclusively of soft­bodied forms. Although named after a site in Australia, the Ediacara formation is worldwide in distribution and dates to Precambrian times. This 700­million­year­old formation gives few clues to the origins of modern animals, however, because paleontologists believe it represents an evolutionary experiment that failed. It contains no ancestors of modern animal groups. 8. Which of the following is NOT mentioned in Paragraph4 as being true of the Ediacara formation? It contains fossils that date back to the Precambrian period. It contains only soft­bodied animal fossils. It is located on a single site in Australia. It does not contain any fossils of the ancestors of modern animals. Paragraph5: A slightly younger fossil formation containing animal remains is the Tommotian formation, named after a locale in Russia. It dates to the very early Cambrian period, and it also contains only soft­bodied forms. At one time, the animals present in these fossil beds were assigned to various modern animal groups, but most paleontologists now agree that all Tommotian fossils represent unique body forms that arose in the early Cambrian period and disappeared before the end of the period, leaving no descendants in modern animal groups. 9. 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. The animals found in the Tommotian fossil bed were once thought to belong to a variety of modern animal 197 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 groups, but now they are thought to have descended from a single group. Animals in the Tommotian fossil beds were initially assigned to modern animal groups but are now thought to belong to groups that emerged and died out during the Cambrian period. Though at first they thought otherwise, paleontologists now agree that the animals in the Tommotian have body forms from which modern animals have descended. It is unclear whether the Tommotian fossils from the early Cambrian period represent unique body forms or whether they should be assigned to various modern animal groups. Paragraph6: A third fossil formation containing both soft­bodied and hard­bodied animals provides evidence of the result of the Cambrian explosion. This fossil formation, called the Burgess Shale, is in Yoho National Park in the Canadian Rocky Mountains of British Columbia. Shortly after the Cambrian explosion, mud slides rapidly buried thousands of marine animals under conditions that favored fossilization. These fossil beds provide evidence of about 32 modern animal groups, plus about 20 other animal body forms that are so different from any modern animals that they cannot be assigned to an...
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This note was uploaded on 09/17/2013 for the course LANGUAGE 13DL208 taught by Professor Wang during the Fall '13 term at East China Normal University.

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