GRE閱讀｜The deep sea typically has a sparse fauna dominated by tiny worms and crustaceans @ 熱血背包客莊ㄟ

The deep sea typically has a sparse fauna dominated by tiny worms and crustaceans, with an even sparser distribution of larger animals. However, near hydrothermal vents, areas of the ocean where warm water emerges from subterranean sources, live remarkable densities of huge clams, blind crabs, and fish.

Most deep-sea faunas rely for food on particulate matter, ultimately derived from photosynthesis, falling from above. The food supplies necessary to sustain the large vent communities, however, must be many times the ordinary fallout. The first reports describing vent faunas proposed two possible sources of nutrition: bacterial chemosynthesis, production of food by bacteria using energy derived from chemical changes, and advection, the drifting of food materials from surrounding regions. Later, evidence in support of the idea of intense local chemosynthesis was accumulated: hydrogen sulfide was found in vent water; many vent-site bacteria were found to be capable of chemosynthesis; and extremely large concentrations of bacteria were found in samples of vent water thought to be pure. This final observation seemed decisive. If such astonishing concentrations of bacteria were typical of vent outflow, then food within the vent would dwarf any contribution from advection. Hence, the widely quoted conclusion was reached that bacterial chemosynthesis provides the foundation for hydrothermal-vent food chains—an exciting prospect because no other communities on Earth are independent of photosynthesis.

There are, however, certain difficulties with this interpretation. For example, some of the large sedentary organisms associated with vents are also found at ordinary deep-sea temperatures many meters from the nearest hydrothermal sources. This suggests that bacterial chemosynthesis is not a sufficient source of nutrition for these creatures. Another difficulty is that similarly dense populations of large deep-sea animals have been found in the proximity of “smokers” – vents where water emerges at temperatures up to 350°C. No bacteria can survive such heat, and no bacteria were found there. Unless smokers are consistently located near more hospitable warm-water vents, chemosynthesis can account for only a fraction of the vent faunas. It is conceivable, however, that these large, sedentary organisms do in fact feed on bacteria that grow in warm-water vents, rise in the vent water, and then rain in peripheral areas to nourish animals living some distance from the warm-water vents.

Nonetheless, advection is a more likely alternative food source. Research has demonstrated that advective flow, which originates near the surface of the ocean where suspended particulate matter accumulates, transports some of that matter and water to the vents. Estimates suggest that for every cubic meter of vent discharge, 350 milligrams of particulate organic material would be advected into the vent area. Thus, for an average-sized vent, advection could provide more than 30 kilograms of potential food per day. In addition, it is likely that small live animals in the advected water might be killed or stunned by thermal and/or chemical shock, thereby contributing to the food supply of vents.

For the following question, consider each of the choices separately and select all that apply

1. The passage provides information for answering which of the following questions EXCEPT?

(A) What causes warm-water vents to form?

(B) What role does hydrogen sulfide play in chemosynthesis?

2. The information in the passage suggests that the majority of deep-sea faunas that live in nonvent habitats have which of the following characteristics?

(A) They do not normally feed on particles of food in the water.

(B) They are smaller than many vent faunas.

(D) They derive nutrition from a chemosynthetic food source.

(E) They congregate around a single main food source.

3. Select the sentence in the passage in which the author implies that vents are colonized by some of the same animal found in other areas of the ocean floor, which might be a weakness for the bacterial chemosynthesis model.

4. The author refers to "smokers" in the third paragraph most probably in order to

(A) show how thermal shock can provide food for some vent faunas by stunning small animals

(B) prove that the habitat of most deep-sea animals is limited to warm-water vents

(D) demonstrate how advection compensates for the lack of food sources on the seafloor

(E) present evidence that bacterial chemosynthesis may be an inadequate source of food for some vent faunas

結構分析：

長文章每段的開頭都是重點，必看，然後接下來每段主題句他們後面如果接上了轉折，這個也要特別注意，再來可以忽略的句子就是有代名詞出現的話，因為代名詞表示他前面還沒說完，然後打上句點換一口氣繼續屁，因此可以先行不看等到題目有問到我們再來處理。

第一段：

The deep sea typically has a sparse fauna dominated by tiny worms and crustaceans, with an even sparser distribution of larger animals. 逗點後面的with...這只是補充使得主幹說的東西沒有那麼絕對，既然非主幹，因此也是可以不用看拉，整理一下：有深海，有動物，這些動物是小蟲跟小節肢動物，這個組合可以知道發生地點在比奇堡，皮老闆 VS. 蟹老闆。等等可能再補個大鳳梨，跟蟹堡王美味蟹堡。

However, near hydrothermal vents, areas of the ocean where warm water emerges from subterranean sources, live remarkable densities of huge clams, blind crabs, and fish.

因為是轉折字眼，所以必看的拉～～這邊提到地點：vent，有大動物，那這些大動物後面有舉例，可看可不看，因為整合這段會發現這好像就是一個戲劇的開頭一樣，先來個人物介紹，然後這段同時也在限定主題，就是however後面的東西，轉折後面的東西才是重點，所以等等討論的走勢可能會討論深海，的那個洞vent，的那個大型動物huge clams, blind crabs, and fish.

第二段：

Most deep-sea faunas rely for food on particulate matter, ultimately derived from photosynthesis, falling from above.

這些動物的食物是particulate matter, 這個兩個字沒錯就是PM2.5的那個PM，就做懸浮微粒，然後, ultimately ...都補充拉就略過了，最後那個關係代名詞子句falling from above.從天而降，也是在做補充，這就不理他了，既然主題句說大部分的海底動物都是吃PM的，所以可以想像等等文章發展一定跟吃有關，往下看，因為我們只知道這段要探討食物，但是方向不夠啊，有可能他在討論這些食物怎麼來，還是依照剛剛第一段分類完動物類別之後，這段接著補充各類動物所覓食的東西，這都有可能，所以顯然知道的內容不夠繼續看下去。

The food supplies necessary to sustain the large vent communities, however, must be many times the ordinary fallout.

這剛好有來一個轉折字眼，所以本來就是要稍微注意了，這裡換個角度已經在討論vent的動物了喔，所以還是跟著第一段延續，我們只講到『深海動物當中住在vent附近的大型動物』，後面帶出內容是他們吃很多，感覺還是不踏實，這個很合乎常理，但感覺也是沒講到內容，所以再往下看一點點好了。

The first reports describing vent faunas proposed two possible sources of nutrition: bacterial chemosynthesis, production of food by bacteria using energy derived from chemical changes（同位語就別看了，因為她倆逗點之間不是完整句子也沒連接詞，只用一個名詞開頭所以一定是同位語修飾bacterial chemosynthesis）, and advection, the drifting of food materials from surrounding regions. （這也是同位語，這個修飾advection）。

因此這句話得到了vent faunas兩種食物來源，可能的喔！！一為ＢＣ，他者為ＡＤ，但是其實建議這個不要看，因為這裡已經出現列舉字眼The first 然後又給一個論據字眼reports，然而你我都知道，包括有驊也知道，就是天下的論據都是在支持論點的，而我們剛拿到考題第一步只是要先抓架構，這種支持的東西已經是進入到具體細節了，都算是補充說明用的而已，因此講的東西只是將架構上的概念給具體化而已，所以要忽略不看才行，然後下一句的Later, evidence.....這個是接著講第二個證據，這個更不該看了，所以本段只要把however那句話看完就夠了，但是剛剛也說到這樣感覺內容不太夠，可是接下來都是例子啊，都是細節，怎麼辦，直接看到結論。

Hence, the widely quoted conclusion was reached that bacterial chemosynthesis provides the foundation for hydrothermal-vent food chains—an exciting prospect because no other communities on Earth are independent of photosynthesis.

這個結論型副詞帶頭應該很好找拉～～～，所以這裡看完之後，提供一個重要關鍵bacterial chemosynthesis，vent food 所以跟本段主題聯結之後，大致上可以知道風洞區的動物他們的食物跟ＢＣ很有關係。好拉這樣就可以稍微結案了，感覺上是講來源說，所以我猜測這段應該是講說vent區的食物怎麼生出來的。

第三段：

There are, however, certain difficulties with this interpretation.

這段光是看到however,和下一句話的For example,之後我整個人偷笑，因為however轉折啊，然後這句話說這個解釋有問題，有難言之隱，所以推回上一句話可以得知等等要說的絕對是：風洞區的動物他們的食物跟ＢＣ很有關係，你確定嗎？？非然也喔！！由原本的肯定句變成疑問句了，然後進一步變否定，接下來句子安排For example這個字就表示要講例子了啊，都進入細節了我何必看，直接跳過，然後第三句Another difficulty這裡的『另一個』又讓我不用看了，這就是接續剛剛第二句的For example作者覺得舉例不夠多，然後再來一發，所以我直接把目光拉到第四句。

No bacteria can survive such heat, and no bacteria were found there.由剛開頭的difficulties接這句話No bacteria can survive算是給一個交代給理由，那其實也是可以跳過的，因為所以這種因果關係也是互補的，我的任務是先抓架構，考試時把自己當作那種只會問『然後勒』，『所以勒』的公司主管，凡事只問結果不問過程，這些囉嗦的解釋有考到在看。所以我繼續仙人跳來到第五句，這個也不用看了拉Unless這個字表示條件了，這個已經是細節到不行的東西，因為條件表示限定範圍，也就是文章從一個很抽象的概念，接下來轉具體例證之後，現在已經來到特別條件下的情形，這個已經是狹義的定義了。

跳來跳去來到最後一句。

It is conceivable, however, that these large, sedentary organisms do in fact feed on bacteria that grow in warm-water vents, rise in the vent water, and then rain in peripheral areas to nourish animals living some distance from the warm-water vents.

這裡給出了三組東西，都藏在關係代名詞裡，分別是

一：that grow in warm-water vents,

二：rise in the vent water,

三：and then rain in peripheral areas to nourish animals.

conceivable直接當作I agree，Ｉdo，我願意，看待。這個these large, sedentary organisms他有個these代名詞就是vent區的動物啊，由結構上可以斷定，本段開頭是要說明第二段有瑕疵，所以看第二段的主角是large vent communities，所以不是講別人就是講這些大動物。然後however,出現表示剛剛那些difficulties的內容全都是廢話都被這個however,打槍了，哈哈～～還好剛剛這麼一大串的內容沒有看，不然我這下子真的賭輸錢還泡茶給別人喝。

總結一下第三段：前面先說ＢＣ不靠譜，然後給出不靠譜的證據一，二，接著however出現在反駁一次正個不靠譜（difficulty）的言論，進而最後使得文章邏輯是支持第二段的，也就是『ＢＣ是對的』，vent的動物，食物確實跟Ｂ有關，這些Ｂ是grow in warm-water，rise in the vent and rain in peripheral areas，白話一點，vent區的動物靠這些在溫水區著床，茁壯後跑出洞在散落於洞周邊的細菌吃飯。在更簡單一點，vent區的覓食跟細菌有關。因此老話一句，剛剛那個特地分出來的三組東西是關係代名詞裡面的內容，既然是修飾詞，修飾細菌，所以基本上也是不用看低。

第四段：

Nonetheless, advection is a more likely alternative food source. 這裡在轉折，提到ad也是另外一個食物來源，這裡轉折就是在轉bacterial chemosynthesis VS. advection完全呼應剛剛The first reports describing vent faunas proposed two possible sources of nutrition: 所以證明當初不看是對的。

接著後面又來了一些舉例的字眼這些就一律跳過了。

Research has demonstrated that advective flow, which originates near the surface of the ocean where suspended particulate matter accumulates, transports some of that matter and water to the vents. Estimates suggest that for every cubic meter of vent discharge, 350 milligrams of particulate organic material would be advected into the vent area. Thus, for an average-sized vent, advection could provide more than 30 kilograms of potential food per day. In addition, it is likely that small live animals in the advected water might be killed or stunned by thermal and/or chemical shock, thereby contributing to the food supply of vents.

這一串我們只抓這個看，因為又看到表結論的副詞：Thus, for an average-sized vent, advection could provide more than 30 kilograms of potential food per day.

哇這個只是提供ad能夠製造食物的量的數據，可是我們要關心的事情是ad倒底是不是食物來源，而這句話已經表明認定是了，是食物來源沒錯，並且在『補充』到底提供多少食物，所以已經在細節裡面繞了，我們其實也可以略掉。

第一題：

多選題還是個別看會比較保險。

(A) What causes warm-water vents to form?

關鍵字溫水區，然後邏輯字是因果，可是回看第三段說到It is conceivable, however, that these large, sedentary organisms do in fact feed on bacteria that grow in warm-water vents, rise in the vent water, and then rain in peripheral areas to nourish animals living some distance from the warm-water vents.這是在限定形容那個細菌是怎樣的細菌，當作修飾細菌的詞，並沒有對溫水做因果分析，他的角色錯誤，再說本文是在討論怎麼找東西吃，既然如此因該會有生存的字眼或是食物的東西出現才對。

(B) What role does hydrogen sulfide play in chemosynthesis?

硫化氫的東西角色扮演，這個關鍵字找到了第二段，這題目真夠麻煩的考細節考那麼細，結構圖畫出來都還不能解題，根據硫化氫定位到：

Later, evidence in support of the idea of intense local chemosynthesis was accumulated: hydrogen sulfide was found in vent water; many vent-site bacteria were found to be capable of chemosynthesis; and extremely large concentrations of bacteria were found in samples of vent water thought to be pure.

只看到硫化氫在哪被發現的而已，沒有深入說他被發現之後繼續研究倒底他是幹嗎用的，沒有。所以錯誤選項。

如果由結構上來看，這句話先其實只要看到evidence就確定是錯誤選項了，因為垃圾不分藍跟綠，證據只分『有』跟『無』，不會問到說硫化氫扮演『何種』角色，假設問到扮演什麼角色，這是已經事先確定有這件事了，然後有這件事我們下一個邏輯才能接那既然有的話，那這個東西是幹啥用的，所以屬於解釋型的文章，可是現在的文章內容是舉例型，舉例不具延伸現象只具有贊成或反對的緞子給出一個具體的事物，譬如說：誒～你不信是不是，我拿東西給你看，所以這裡只會有兩種情形討論，一是：哇～還真的有椰，二是：乾～你唬爛小，這根本不是好不好。回到本題題目主幹是：evidence was accumulated，講的就是我知道證據，然後後方的分號在說明哪些東西被你收集到了，其中hydrogen sulfide就是被搜集到的東西之一。另一個解釋是，那個分號，兩個關鍵字被兩組分號隔開，他們當然不能混為一談，ETS最好這一味類似拼裝車，ＡＢ車的選項。

冒煙的箘，對應到第三段同時有煙又有細菌的句子：

Another difficulty is that similarly dense populations of large deep-sea animals have been found in the proximity of “smokers” – vents where water emerges at temperatures up to 350°C. No bacteria can survive such heat, and no bacteria were found there.前句給環境條件後句給yes or no

這題很花時間幾乎考到細節裡去了。選（Ａ）（Ｂ）

第二題：

題目出到推理題，主角是大部分的deep-sea faunas，那這解題方式只會有一種：對比推理法。因此看到結構圖上去找『對比對象』吧，majority = typical所以對象就是無vent區動物 VS. 有vent區動物，兩者關係必然相反啊，然後題目問的是無vent區的動物如何，所以要看到有vent的動物，它所帶給你的資訊是啥，之後再取『反』就是答案了。所以只有看到small VS. huge。秒選（Ｂ）

第三題：

Select the sentence in the passage in which the author implies that vents are colonized by some of the same animal found in other areas of the ocean floor, which might be a weakness for the bacterial chemosynthesis model.

這又來一個推理題，看來這推理題不是對象比較的題型，題目大致上解釋是哪一句話使得ＢＣ不成立，因此換言之就是找打槍反對的字眼，回看結構圖就是那個difficult，所以找回去文章第三段，There are, however, certain difficulties with this interpretation. 這句話看文只能是完成一半，他就等於是weakness，只是個邏輯轉換作用的句子，因此還要接下去看他的內容所以就是他的下一句話了。For example，天下的for example都是正面支持論點的你應該會說金城武很帥，證據是我看到他在伯朗大道騎腳踏車的模樣微風吹來，頭髮飄逸，I see you帥啊。但是你總不可能去說金城武很帥，我看到他騎腳踏車在伯朗大道上一陣強風把他的襯衫吹到頭上蓋住視線，結果撞到那棵樹，之後犁田到田邊，這應該不太帥吧，所以回來for example正面支持difficulties，而第三段論點就是要來打槍ＢＣ，所以得証＃

For example, some of the large sedentary organisms associated with vents are also found at ordinary deep-sea temperatures many meters from the nearest hydrothermal sources.

第四題：

這修辭目的題，題目看到smokers對應：

Another difficulty is that similarly dense populations of large deep-sea animals have been found in the proximity of “smokers” – vents where water emerges at temperatures up to 350°C.

整句話標定之後不要看，因為他是問他出現是要幹啥用的，所以在考句子和句子之間的關係，因此句間邏輯是首要關心的目標，看到Another出現，不是阿拿搭，這表示前面還有一組並列的東西，這裡才會說另一個續攤，那這表示前面的句子跟這句的屬性是一樣的，你才能用Another 連接。所以看到上一句話：This suggests that bacterial chemosynthesis is not a sufficient source of nutrition for these creatures.很可惜這句話this壞了一鍋粥，因為前面講過現在用代名詞代替，並且看到suggests表示在對上一句做總結，所以還要再看上一句。

For example, some of the large sedentary organisms associated with vents are also found at ordinary deep-sea temperatures many meters from the nearest hydrothermal sources.

看到For example, 這太高興了，這樣我就可以知道他跟another.....的句子都是屬於論據了，然後論據支持論點而且又是正面支持，最後再依照學術文章最常用的方式：先論點在論據，先抽象在具體，先概論在細節，這樣的發展，再加上一個關鍵：論據基本上都是跟主題句有所對應

最後我們目標直接找到：There are, however, certain difficulties with this interpretation. 答案就是用來反對ＢＣ學說的，this interpretation＝bacterial chemosynthesis 。選（Ｅ）

以上整理內容能幫上忙，喜歡，或是不喜歡還是有錯誤，歡迎留言指教，謝謝!!