求教THE CAMBRIAN EXPLOSION两题

Jerrynan

Scientists have asked important questions about this explosion for more than a century. Why did it occur so late in the history of Earth? The origin of multicellular forms of life seems a relatively simple step compared to the origin of life itself. Why does the fossil record not document the series of evolutionary changes during the evolution of animals? Why did animal life evolve so quickly? Paleontologists continue to search the fossil record for answers to these questions.
One interpretation regarding the absence of fossils during this important 100-million-year period is that early animals were soft bodied and simply did not fossilize. Fossilization of soft-bodied animals is less likely than fossilization of hard-bodied animals, but it does occur. Conditions that promote fossilization of soft-bodied animals include very rapid covering by sediments that create an environment that discourages decomposition. In fact, fossil beds containing soft-bodied animals have been known for many years.

6.、Which of the following best describes the relationship between Paragraph2 and Paragraph3?
?A、Paragraph2 puts forward several scientific claims, one of which is rejected in Paragraph3
?B、Paragraph2 poses several questions, and Paragraph3offers a possible answer to one of them
?C、Paragraph2 presents outdated traditional views, while Paragraph3presents the current scientific conclusions.
?D、Paragraph2 introduces a generalization that is illustrated by specific examples in Paragraph3
答案选B，但是A为什么不对呢？我觉得第三段开始说软体动物不容易形成化石，后来又说是可以的，还给了后几段的几个典型例子。应该是说第二段中的这种解释不成立。

14、The term “Cambrian explosion” refers to the geologically brief period during which all modern animal groups evolved.
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Answer Choices
1. Little is known about the stages of evolution during the Cambrian period, in part because early animals were soft bodied and could fossilize only under particular conditions.
2. While animal fossils from before the Cambrian explosion have no modern descendants, many animals that evolved during the Cambrian explosion can be assigned to modern groups.
3. The Cambrian period is significant because it marks the emergence of eukaryotic life-forms – organisms that have cells with true nuclei
4. The Ediacara fossil formation provides the most information about the Cambrian explosion, while the earlier, Tommotian and Burgess Shale formations give clues about Precambrian evolution.
5. Zoologists are awaiting the discovery of a 600-million-year-old fossil formation in order to be able to form a theory of how animal evolution progressed.
6. Although the reasons for the rapid evolution of animals during the Cambrian period are not known, one proposed explanation is an abundance of niches with a lack of competitors.
答案是1、2、6。但是3、5错在哪里了呢？而且我觉得1、2并不正确

恩，麻烦各位了哈~~

Jerrynan

顶~~麻烦CDer帮帮忙~~

切尔西

我给你说下第6题的那个吧，14题的那个没有全文或者相应的段落做不了的

第六题那个，A选项中，说第二段提出了一个claim, 但是第二段中一直在说的都是一些问题，没有提出任何claim, 而且第三段的开头就提出说科学家提出了一个可能的解释，虽然最后有证据证明软体动物的化石是存在的，但是不能否定软体动物更难行程化石导致了这个结果，因此只是否定了一个那个解释的一个方面，在其他证据或者发现给出前，这个可能的解释还是成立的

Jerrynan

多谢了哈~~这么讲的话明白了不少~~(*^__^*)