gwd6 5-7

Q5 to Q7:

      According to a theory advanced

       by researcher Paul Martin, the wave

       of species extinctions that occurred

Line       in North America about 11,000 years

  (5)       ago, at the end of the Pleistocene era,

can be directly attributed to the arrival

of humans, i.e., the Paleoindians, who

were ancestors of modern Native

Americans.  However, anthropologist

(10)      Shepard Krech points out that large

animal species vanished even in areas

where there is no evidence to demon-

strate that Paleoindians hunted them.

Nor were extinctions confined to large

(15)      animals:  small animals, plants, and

insects disappeared, presumably not

all through human consumption.  Krech

also contradicts Martin’s exclusion of

climatic change as an explanation by

(20)      asserting that widespread climatic

       change did indeed occur at the end of

       the Pleistocene.  Still, Krech attributes

secondary if not primary responsibility

for the extinctions to the Paleoindians,

(25)      arguing that humans have produced

local extinctions elsewhere.  But,

according to historian Richard White,

even the attribution of secondary

responsibility may not be supported

(30)      by the evidence.  White observes that

Martin’s thesis depends on coinciding

dates for the arrival of humans and the

       decline of large animal species, and

Krech, though aware that the dates

(35)      are controversial, does not challenge

them; yet recent archaeological

discoveries are providing evidence

that the date of human arrival was

much earlier than 11,000 years ago.

--------------------------------------------------------------------------------

Which of the following, if true, would most weaken Krech’s objections to Martin’s theory?

我也选了C

这么想的：K反对M之处在于K认为1：天气是一个影响因素,因为climatic change did indeed occur at the end of  the Pleistocene. 。2：hunting至少不是首要原因，因为“large animal species vanished even in areas where there is no evidence to demonstrate that Paleoindians hunted them”

c说climatic change occurred not only at the end of the Pleistocene era but also in previous and subsequent eras，是一个有因无果的削弱（在承认原文开头所说的extinction发生在the end of the Pleistocene era 的前提下）

B说的Nor were extinctions confined to large  animals:  small animals, plants, and insects disappeared, presumably not all through human consumption。没看懂意思，请问这句话是谁的立场？我觉得是K的。

请大家帮我看看我的错在哪里，B对在哪里？

谢谢！

http://forum.chasedream.com/dispbbs.asp?boardid=25&star=2&replyid=646379&id=69442&skin=0&page=1

看了这个贴子，还是没搞明白，觉得流沙的举og的例子有道理，但是跟本题又有些不同

困惑中！