GWD3-Q38:

Kate:  The recent decline in numbers of the Tennessee warbler, a North American songbird that migrates each fall to coffee
plantations in South America, is due to the elimination of the dense tree cover that formerly was a feature of most
South American coffee plantations.

Scott:  The population of the spruce budworm, the warbler’s favorite prey in North America, has been
dropping.  This is a more likely
explanation of the warbler’s decline.

Which of the following, if true,most seriouslycalls Scott’s hypothesis into question?

1. The numbers of the Baltimore oriole, a songbird that does not eat budworms but is as dependent on
        South American coffee plantations as is the Tennessee warbler, are
        declining.
2. The spruce-budworm population has dropped because of a disease that can infect budworms but
        not Tennessee
        warblers.
3. The drop in the population of the spruce budworm is
        expected to be only temporary.
4. Many Tennessee warbler have begun
        migrating in the fall to places other than traditional coffee plantations.
5. Although many North American
        songbirds have declined in numbers, no other species has
        experienced as great a decline as has the Tennessee warbler.

我自己的解釋如下:

A 無關比較，有果無因。

B 無關比較。蟲得病會減少，但是此病對鳥沒有影響。

C 蟲減少的原因只是暫時的，但鳥數量持續減少，表示鳥減少的數量另外有其他原因。我這樣認為,但是這樣的思維似乎有錯.

D 的答案並沒有牽涉到蟲子的減少, 其實是可以解釋鳥變少的原因,但並不是針對Scott提到的論點而加以削弱,所以一開始實在沒辦法選這答案.

E 擴大範圍，無關比較。題目只問Tennessee warbler減少的原因，沒問到其他鳥。

这一题TN的答案的确是A，但是我觉得A有问题啊。 A说了另外一种鸟，Baltimore

oriole怎么怎么样，我觉得这跟题目中说的无关啊。这种鸟怎么样，跟Tennessee

warbler减少的原因有什么关系？

我一开始也是选的C。因为食物的减少是暂时的，食物还会增加的，所以说食物减少是鸟

减少的原因不对。

NN出来说说啊

这一题TN的答案的确是A，但是我觉得A有问题啊。 A说了另外一种鸟，Baltimore oriole怎么怎么样，我觉得这跟题目中说的无关啊。这种鸟怎么样，跟Tennessee warbler减少的原因有什么关系？

我一开始也是选的C。因为食物的减少是暂时的，食物还会增加的，所以说食物减少是鸟减少的原因不对。

NN出来说说啊

Kate说：田纳西莺（一种每年秋季会迁徙到南美洲咖啡园的会唱歌的鸟）的减少是由于南美洲dense tree cover的消失

Scott说：spruce budworm这种虫是田纳西莺在北美洲最喜欢的事物，减少了。这更可能是田纳西莺减少的原因

题目问，哪个削弱Scott的说法。

选项A，巴尔的摩oriole，和田纳西莺的共同点是都以来南美洲的咖啡园，不同点是不吃budworm。oriole的数量也在减少。

A选项说明，budworm的减少对依赖南美洲咖啡园的鸟的数量没有影响，而咖啡因的tree cover的消失可能是依赖南美洲咖啡园的鸟数量减少的原因。支持Kate的说法，削弱Scott的说法。

不是牛人，不知说清楚了没有……

it has been mentioned in A that Baltimore oriole "is as dependent on South American coffee plantations as is the Tennessee warbler". So it can be made that the reason of decline of BO is the same as TW.

Not sure if am correct.

已经够牛了