[讨论]GWD27-22

ssl507

顶

asong

d 排除他因，为什么不对呢？

mimixiaxia

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wsdoll

???

阿土莎莎

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eileenmu木

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xiaoda

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craigchsieh

以下是引用hsyeng在2006-8-12 2:06:00的发言：

Whales originated in the freshwater lakes and rivers of ancient Asia about sixty million years ago.  Not until about ten million years later did species of whales develop specialized kidneys enabling them to drink salt water.  Although fossil evidence shows that some early whale species that lacked such kidneys sometimes swam in the Earth’s saltwater oceans, these species must have had to return frequently to freshwater rivers to drink.

Which of the following is most strongly supported by the information given?

1. Fossils of whale species dating from between sixty million and fifty million years ago will not be found on continents that were at the time separated from ancient Asia by wide expanses of ocean.

答案給A請大家幫忙解答~

请问A选项中的between sixty million and fifty million years ago，按原文不是说这段期间已经有能力drink salt water，为什么不能在隔着海洋的地方发现化石呢？而且some early whale species不能在咸水久待，那也只是some不具代表性吧？

[此贴子已经被作者于2008-8-4 21:59:37编辑过]

craigchsieh

help~

[此贴子已经被作者于2008-8-6 16:53:39编辑过]

86spinach

以下是引用craigchsieh在2008-8-4 21:52:00的发言：

答案給A請大家幫忙解答~

请问A选项中的between sixty million and fifty million years ago，按原文不是说这段期间已经有能力drink salt water，为什么不能在隔着海洋的地方发现化石呢？而且some early whale species不能在咸水久待，那也只是some不具代表性吧？
        

偶理解啊,题目说Not until about ten million years later did species of whales develop specialized kidneys enabling them to drink salt water.
    

就是题目假设了直到ten million years 那天才有这个喝咸水的功能,之前是没有或不完全的,根据题目永远是对的原则,加上板块的演化来看(亚洲大陆隔着海好像都挺远)
    

so~~在sixty million and fifty million years ago之间whales们走不了那么远~~
    

附上板块地图 咔咔~~ 亚洲在右上