2020考研英語閱讀理解精讀100篇：Unit 50

Unit 50

① The once radical notion that birds descended from dinosaurs—or may even be dinosaurs, the only living branch of the family that ruled the earth eons ago—has got stronger and stronger since paleontologists first started taking it seriously a couple of decades ago. Remarkable similarities in bone structure between dinos and birds were the first clue. Then came evidence, thanks to a series of astonishing discoveries in China’s Liaoning province over the past five years, that some dinosaurs may have borne feathers. But a few scientists still argued that the link was weak; the bone similarities could be a coincidence, they said. And maybe those primitive structures visible in some fossils were feathers—but maybe not. You had to use your imagination to see them.

Not anymore. A spectacularly preserved fossil of a juvenile dinosaur, announced by a team of paleontologists from the Chinese Academy of Geological Sciences and New York City’s American Museum of Natural History in the latest issue of Nature, is about as good a missing link as anyone could want. “It has things that are undeniably feathers,” exults Richard Prum, of the University of Kansas Natural History Museum, an expert on the evolution of feathers. “But it is clearly a small, vicious theropod similar to the velociraptors that chased the kids around the kitchen in Jurassic Park.”

The find helps cement the dinosaur-bird connection, but it also casts new light on the mystery of why nature invented feathers in the first place. For the better part of a century, biologists have assumed that these specialized structures evolved for flight, but that’s clearly not true. “The feathers on these dinosaurs aren’t flight-worthy, and the animals couldn’t fly,” says paleontologist Kevin Padian, of the University of California, Berkeley. “They’re too big, and they don’t have wings.” So what was the original purpose of feathers? Nobody knows for sure; they might have been useful for keeping dinos dry, distracting predators or attracting mates, as peacocks do today.

② But many biologists suspect that feathers originally arose to keep dinosaurs warm. The bone structure of dinosaurs shows that, unlike modern reptiles, they grew as fast as birds and mammals—which dovetails with a growing body of evidence that dinos were, in fact, warm-blooded. Says Padian: “They must have had a high basal metabolic rate to grow that fast. And I wouldn’t be surprised if they had some sort of skin covering for insulation when they were small.” Says Norell: “Even baby tyrannosaurs probably looked like this one.”

At the rate feathered dinosaurs are turning up, it shouldn’t take long to solidify scientists’ understanding of precisely how and why feathers first arose and when the first birdlike creature realized they were useful for flight. Meanwhile, kids had better get used to the idea that T. rex may have started life looking an awful lot like Tweety Bird.

注（1）：本文選自The New York Times；

注（2）：本文習(xí)題命題模仿對象：第1、2、3、5、4題分別模仿1999年真題Text 2的1、2、3、5題和Text 4的第3題。

1. We learn from the beginning of the passage that ______.

A) scientists are split as to whether birds descended from dinosaurs

B) the bone similarities between birds and dinosaurs are a coincidence

C) fossils have proven that birds evolved from dinosaurs

D) the idea that birds are connected with dinosaurs has always been taken seriously

2. Speaking of the recently-announced fossil of a juvenile dinosaur, the author implies that ______.

A) it shows vividly how dinosaur flies

B) it brings new mystery to paleontologists

C) it further proves the link between birds and dinosaurs

D) it solves the puzzle of birds’ evolution

3. In the view of Kevin Padian, the feathers on those dinosaurs ______.

A) were of no practical value

B) were useful for flight

C) could protect dinosaurs from their natural enemy

D) were good for insulation

4. The original purpose of feather was ______.

A) to help dinosaurs fly

B) to keep dinosaurs warm

C) to distract predators

D) a mystery

5. We learn from the last paragraph that ______.

A) a baby dinosaur looks like a bird

B) T-rex is a kind of dinosaur figure familiar to kids

C) living feathered dinosaurs can still be found in certain parts of the world

D) scientists understand precisely how and why feathers first arose

篇章剖析

本文是一篇說明文，對新發(fā)現(xiàn)的恐龍化石所揭示的恐龍與鳥類之間的關(guān)系進(jìn)行了說明。文章第一段介紹了一種認(rèn)為恐龍與鳥類之間關(guān)系密切的觀點(diǎn)以及科學(xué)界對這種觀點(diǎn)的態(tài)度變化；第二段介紹了一個古生物學(xué)家研究小組的最新發(fā)現(xiàn)；第三段說明了這次發(fā)現(xiàn)的重要意義；第四段介紹了科學(xué)家對于恐龍羽毛的作用的看法；最后一段描述了恐龍和鳥類關(guān)系研究的前景。

詞匯注釋

dinosaur /?da?n?s??/ n. 恐龍

paleontologist /?p?l??n?t?l?d??st/ n. 古生物學(xué)家

dino dinosaur的簡寫

fossil /?f?sl/ n. 化石

juvenile /?d?u?v?na?l/ adj. 少年的，沒有完全長成的或沒有發(fā)育完全的；年輕的

vicious /?v???s/ adj. （動物）兇猛的

theropod /?θ??r?p?d/ n. 【古生】獸腳亞目食肉恐龍（前肢小，主要用后肢行走）

velociraptor /?vel??s?r?pt?/ n. 【古生】迅猛龍

Jurassic Park 好萊塢導(dǎo)演斯皮爾伯格執(zhí)導(dǎo)的《侏羅紀(jì)公園》

jurassic /d????r?s?k/ n. 【地】侏羅紀(jì)的，侏羅系的（屬于或界定為中生代時代第二期的時間和礦床的，該時期以恐龍的存在和最早的哺乳動物和鳥類的出現(xiàn)為特征）

cement /s??ment/ v. 粘結(jié)，膠合，（像水泥一樣）鞏固

distract /d?s?tr?kt/ v. （常與from連用）使…注意力轉(zhuǎn)移；使分心

predator /?pred?t?/ n. 掠食者，食肉動物

reptile /?repta?l/ n. 爬行動物

mammal /?m?m?l/ n. 哺乳動物

dovetail /?d?vte?l/ v. 吻合

metabolic /?met??b?l?k/ adj. 代謝作用的，新陳代謝的

insulation /??nsj??le???n/ n. 阻熱，隔熱，絕熱

tyrannosaur /t??r?n??s??/ n. 霸王龍（上白堊紀(jì)北美洲的一種大型食肉恐龍，前肢小且頭大）

solidify /s??l?d?fa?/ v. 變凝固，使凝固；變結(jié)實(shí)；使堅(jiān)強(qiáng)

T. rex 暴龍（體型最大的食肉恐龍）

Tweety Bird 小鳥崔弟，好萊塢動畫片系列《崔弟和傻大貓》中的一只黃色小鳥

難句突破

① The once radical notion that birds descended from dinosaurs—or may even be dinosaurs, the only living branch of the family that ruled the earth eons ago—has got stronger and stronger since paleontologists first started taking it seriously a couple of decades ago.

主體句式：The notion has got stronger and stronger.

結(jié)構(gòu)分析：這是一個復(fù)雜長句，句子的主語notion帶有一個同位語從句，這個同位語從句中又有一個含有同位語（the only living branch）和定語從句（family后面由that引導(dǎo)的從句）的插入語，主句后面還有一個since引導(dǎo)的時間狀語從句。

句子譯文：鳥類的祖先是恐龍——甚至鳥類本身就是恐龍，是曾經(jīng)在億萬年前統(tǒng)治地球的這個家族中唯一生活到今天的一個分支——這樣的說法曾經(jīng)被視為極端學(xué)說，但自從古生物學(xué)家?guī)资昵暗谝淮握J(rèn)真思考這個問題以來，這種觀點(diǎn)得到了越來越多的支持。

② But many biologists suspect that feathers originally arose to keep dinosaurs warm.

主體句式：Biologists suspect that...

結(jié)構(gòu)分析：這個句子容易出錯的地方就是對于suspect這個詞的理解。雖然漢語翻譯為“懷疑”，但它主要表示某種事情可能是真的，表達(dá)一種肯定，與doubt所表示的懷疑正好相反。

句子譯文：但許多生物學(xué)家猜想羽毛的最初用途是為了給恐龍保暖。

題目分析

1. A 推理題。文章開頭用“the once radical notion”來說明這個觀點(diǎn)曾經(jīng)被視為極端學(xué)說，接著在下文中作者寫道：“But a few scientists still argued that the link was weak”。由此可見對于鳥類是否起源于恐龍，科學(xué)家們有不同的看法。

2. C 推理題。從文章第二段作者對這塊化石的介紹“is about as good a missing link as anyone could want”到第三段第一行the find helps cement the dinosaur-bird connection可以看出這塊化石進(jìn)一步證實(shí)了鳥類和恐龍之間的聯(lián)系。

3. D 細(xì)節(jié)題。文章第三段Kevin分析了羽毛不可能用于飛行的一些理由，接著在第四段里說“I wouldn’t be surprised if they had some sort of skin covering for insulation”?？梢?，Kevin認(rèn)為這些羽毛可能用于給幼年或年輕的恐龍保暖的。

4. D 細(xì)節(jié)題。可以從原文第三段中“So what was the original purpose of feathers? Nobody knows for sure.”看出，對于羽毛最初的功能，人們只能猜想，并沒有確切的答案。

5. B 推理題。本文全文都在講鳥類與恐龍之間的關(guān)系，并在最后一段預(yù)測隨著越來越多長羽毛的恐龍的化石的出現(xiàn)，科學(xué)家們將能夠了解第一個像鳥一樣的生物何時知道羽毛可用于飛翔的。然后作者說孩子們最好習(xí)慣T. rex may have started life looking an awful lot like Tweety Bird這樣的想法。顯然，T. rex應(yīng)該是一個恐龍，而且既然要讓孩子們習(xí)慣恐龍長得像小鳥，那么顯然孩子們是熟悉T-rex這個形象的。

參考譯文

鳥類的祖先是恐龍——甚至鳥類本身就是恐龍，是曾經(jīng)在億萬年前統(tǒng)治地球的這個家族中唯一生活到今天的一個分支——這樣的說法曾經(jīng)被視為極端學(xué)說，但自從古生物學(xué)家?guī)资昵暗谝淮握J(rèn)真思考這個問題以來，這種觀點(diǎn)得到了越來越多的支持?？铸埡网B類骨骼結(jié)構(gòu)的驚人相似是第一條線索。接下來還有證據(jù)。過去五年在中國遼寧的一系列驚人發(fā)現(xiàn)證明一些恐龍也許還長有羽毛。但一些科學(xué)家仍然認(rèn)為兩者之間的聯(lián)系缺乏說服力；他們說骨骼相似也許只是個偶然。那些化石里看見的原始結(jié)構(gòu)也許是羽毛——也許不是。只有通過想象你才能看見它們。

這種情況將一去不復(fù)返。由中國地質(zhì)科學(xué)院和紐約市的美國自然歷史博物館的古生物學(xué)家組成的研究小組在最新一期《自然》雜志上宣布了一個保存極為完好的年輕恐龍化石，它極有可能是人們想要尋找的那個缺失的環(huán)節(jié)?！八砩系臇|西無疑是羽毛，”堪薩斯自然歷史博物館的羽毛進(jìn)化專家理查德·普魯姆高興地說，“但它顯然是一只體型不大卻性情兇猛的獸腳亞目食肉恐龍，有點(diǎn)像《侏羅紀(jì)公園》里在廚房追逐孩子們的那種迅猛龍?！?

這次發(fā)現(xiàn)為恐龍與鳥類之間的聯(lián)系提供了強(qiáng)有力的證據(jù)，還為破解自然最初為何發(fā)明羽毛這個謎團(tuán)帶來了新希望。將近一個世紀(jì)以來，生物學(xué)家一直認(rèn)為這些特殊結(jié)構(gòu)是為了飛行的需要而進(jìn)化出來的，但這種看法顯然錯了?！斑@些恐龍身上的羽毛并不能用于飛行，而且這些動物也不會飛，”加州大學(xué)伯克利分校的古生物學(xué)家凱文·帕迪恩說?！八鼈凅w型太大，而且它們沒有翅膀。”那么羽毛最初的用途是什么呢？沒有人能夠給出確切的答案，它們也許可以幫助恐龍保持干燥，轉(zhuǎn)移掠食者的注意力或者吸引配偶，就像今天的孔雀一樣。

但許多生物學(xué)家猜想羽毛的最初用途是為了給恐龍保暖。恐龍的骨骼結(jié)構(gòu)表明它們不同于現(xiàn)代的爬行動物，它們的生長速度像鳥類和哺乳動物一樣快——這與越來越多證明恐龍實(shí)際上是溫血動物的證據(jù)相吻合。帕迪恩說：“它們的基礎(chǔ)新陳代謝率一定很高才能長那么快。如果它們小的時候身上長有某種阻熱的皮膚遮蓋物，我不會覺得驚訝?！敝Z雷爾說：“連幼年霸王龍跟它都很像?！?

按照這種長羽毛的恐龍化石的發(fā)現(xiàn)速度，要不了多久科學(xué)家們就可以更確切地了解羽毛最初究竟怎樣以及為什么會出現(xiàn)，第一只像鳥一樣的生物是何時發(fā)現(xiàn)這些羽毛可用于飛行的。與此同時，孩子們最好習(xí)慣那種認(rèn)為暴龍也許剛生下來的時候和小鳥崔弟長得差不多的想法。