2020考研英语阅读理解精读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）：本文选自The New York Times；

注（2）：本文习题命题模仿对象：第1、2、3、5、4题分别模仿1999年真题Text 2的1、2、3、5题和Text 4的第3题。

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

本文是一篇说明文，对新发现的恐龙化石所揭示的恐龙与鸟类之间的关系进行了说明。文章第一段介绍了一种认为恐龙与鸟类之间关系密切的观点以及科学界对这种观点的态度变化；第二段介绍了一个古生物学家研究小组的最新发现；第三段说明了这次发现的重要意义；第四段介绍了科学家对于恐龙羽毛的作用的看法；最后一段描述了恐龙和鸟类关系研究的前景。

词汇注释

dinosaur /ˈdaɪnəsɔː/ n. 恐龙

paleontologist /ˌpælɪɒnˈtɒlədʒɪst/ n. 古生物学家

dino dinosaur的简写

fossil /ˈfɒsl/ n. 化石

juvenile /ˈdʒuːvɪnaɪl/ adj. 少年的，没有完全长成的或没有发育完全的；年轻的

vicious /ˈvɪʃəs/ adj. （动物）凶猛的

theropod /ˈθɪərəpɒd/ n. 【古生】兽脚亚目食肉恐龙（前肢小，主要用后肢行走）

velociraptor /ˌveləˈsɪrəptə/ n. 【古生】迅猛龙

Jurassic Park 好莱坞导演斯皮尔伯格执导的《侏罗纪公园》

jurassic /dʒʊəˈræsɪk/ n. 【地】侏罗纪的，侏罗系的（属于或界定为中生代时代第二期的时间和矿床的，该时期以恐龙的存在和最早的哺乳动物和鸟类的出现为特征）

cement /sɪˈment/ v. 粘结，胶合，（像水泥一样）巩固

distract /dɪsˈtrækt/ v. （常与from连用）使…注意力转移；使分心

predator /ˈpredətə/ n. 掠食者，食肉动物

reptile /ˈreptaɪl/ n. 爬行动物

mammal /ˈmæməl/ n. 哺乳动物

dovetail /ˈdʌvteɪl/ v. 吻合

metabolic /ˌmetəˈbɒlɪk/ adj. 代谢作用的，新陈代谢的

insulation /ˌɪnsjʊˈleɪʃən/ n. 阻热，隔热，绝热

tyrannosaur /tɪˈrænəˌsɔː/ n. 霸王龙（上白垩纪北美洲的一种大型食肉恐龙，前肢小且头大）

solidify /səˈlɪdɪfaɪ/ v. 变凝固，使凝固；变结实；使坚强

T. rex 暴龙（体型最大的食肉恐龙）

Tweety Bird 小鸟崔弟，好莱坞动画片系列《崔弟和傻大猫》中的一只黄色小鸟

难句突破

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.

主体句式：The notion has got stronger and stronger.

结构分析：这是一个复杂长句，句子的主语notion带有一个同位语从句，这个同位语从句中又有一个含有同位语（the only living branch）和定语从句（family后面由that引导的从句）的插入语，主句后面还有一个since引导的时间状语从句。

句子译文：鸟类的祖先是恐龙——甚至鸟类本身就是恐龙，是曾经在亿万年前统治地球的这个家族中唯一生活到今天的一个分支——这样的说法曾经被视为极端学说，但自从古生物学家几十年前第一次认真思考这个问题以来，这种观点得到了越来越多的支持。

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

主体句式：Biologists suspect that...

结构分析：这个句子容易出错的地方就是对于suspect这个词的理解。虽然汉语翻译为“怀疑”，但它主要表示某种事情可能是真的，表达一种肯定，与doubt所表示的怀疑正好相反。

句子译文：但许多生物学家猜想羽毛的最初用途是为了给恐龙保暖。

题目分析

1. A 推理题。文章开头用“the once radical notion”来说明这个观点曾经被视为极端学说，接着在下文中作者写道：“But a few scientists still argued that the link was weak”。由此可见对于鸟类是否起源于恐龙，科学家们有不同的看法。

2. C 推理题。从文章第二段作者对这块化石的介绍“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可以看出这块化石进一步证实了鸟类和恐龙之间的联系。

3. D 细节题。文章第三段Kevin分析了羽毛不可能用于飞行的一些理由，接着在第四段里说“I wouldn’t be surprised if they had some sort of skin covering for insulation”。可见，Kevin认为这些羽毛可能用于给幼年或年轻的恐龙保暖的。

4. D 细节题。可以从原文第三段中“So what was the original purpose of feathers? Nobody knows for sure.”看出，对于羽毛最初的功能，人们只能猜想，并没有确切的答案。

5. B 推理题。本文全文都在讲鸟类与恐龙之间的关系，并在最后一段预测随着越来越多长羽毛的恐龙的化石的出现，科学家们将能够了解第一个像鸟一样的生物何时知道羽毛可用于飞翔的。然后作者说孩子们最好习惯T. rex may have started life looking an awful lot like Tweety Bird这样的想法。显然，T. rex应该是一个恐龙，而且既然要让孩子们习惯恐龙长得像小鸟，那么显然孩子们是熟悉T-rex这个形象的。

参考译文

鸟类的祖先是恐龙——甚至鸟类本身就是恐龙，是曾经在亿万年前统治地球的这个家族中唯一生活到今天的一个分支——这样的说法曾经被视为极端学说，但自从古生物学家几十年前第一次认真思考这个问题以来，这种观点得到了越来越多的支持。恐龙和鸟类骨骼结构的惊人相似是第一条线索。接下来还有证据。过去五年在中国辽宁的一系列惊人发现证明一些恐龙也许还长有羽毛。但一些科学家仍然认为两者之间的联系缺乏说服力；他们说骨骼相似也许只是个偶然。那些化石里看见的原始结构也许是羽毛——也许不是。只有通过想象你才能看见它们。

这种情况将一去不复返。由中国地质科学院和纽约市的美国自然历史博物馆的古生物学家组成的研究小组在最新一期《自然》杂志上宣布了一个保存极为完好的年轻恐龙化石，它极有可能是人们想要寻找的那个缺失的环节。“它身上的东西无疑是羽毛，”堪萨斯自然历史博物馆的羽毛进化专家理查德·普鲁姆高兴地说，“但它显然是一只体型不大却性情凶猛的兽脚亚目食肉恐龙，有点像《侏罗纪公园》里在厨房追逐孩子们的那种迅猛龙。”

这次发现为恐龙与鸟类之间的联系提供了强有力的证据，还为破解自然最初为何发明羽毛这个谜团带来了新希望。将近一个世纪以来，生物学家一直认为这些特殊结构是为了飞行的需要而进化出来的，但这种看法显然错了。“这些恐龙身上的羽毛并不能用于飞行，而且这些动物也不会飞，”加州大学伯克利分校的古生物学家凯文·帕迪恩说。“它们体型太大，而且它们没有翅膀。”那么羽毛最初的用途是什么呢？没有人能够给出确切的答案，它们也许可以帮助恐龙保持干燥，转移掠食者的注意力或者吸引配偶，就像今天的孔雀一样。

但许多生物学家猜想羽毛的最初用途是为了给恐龙保暖。恐龙的骨骼结构表明它们不同于现代的爬行动物，它们的生长速度像鸟类和哺乳动物一样快——这与越来越多证明恐龙实际上是温血动物的证据相吻合。帕迪恩说：“它们的基础新陈代谢率一定很高才能长那么快。如果它们小的时候身上长有某种阻热的皮肤遮盖物，我不会觉得惊讶。”诺雷尔说：“连幼年霸王龙跟它都很像。”

按照这种长羽毛的恐龙化石的发现速度，要不了多久科学家们就可以更确切地了解羽毛最初究竟怎样以及为什么会出现，第一只像鸟一样的生物是何时发现这些羽毛可用于飞行的。与此同时，孩子们最好习惯那种认为暴龙也许刚生下来的时候和小鸟崔弟长得差不多的想法。