侏罗纪搏击俱乐部 第168期:全球变暖是罪魁祸首

 　　The K-T boundary marks the end of the age of dinosaurs², and the beginning of the age of mammals.

　　KT界限层标志着恐龙时代的终点和哺乳动物时代的开端。

　　But does the K-T boundary really signify the absolute end of all dinosaurs?

　　不过KT界限层真的标志着所有恐龙的彻底消亡吗？

　　Many experts believe that dinosaurs, are still among us.

　　很多专家认为恐龙仍生活在我们之中。

　　At 65 and a half million years ago, the age of dinosaurs came to an end.

　　在六千五百万年前，恐龙的纪元走向终结。

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　　After that point, mammals were the dominant³ land living creature.

　　在那以后，哺乳动物是陆地上的统治性生物。

　　However, it's important to remember that although the age of dinosaurs came to an end, the dinosaurs themselves did not.

　　但是，不要忘了，尽管恐龙的时代走到了终点，恐龙本身并没有。

　　Well, it turns out that one branch of that group survived, and that's the great group of birds.

　　其实它们中的一个分支得以幸存，那就是如今繁多的鸟类。

　　Birds themselves are the descendants of creatures very closely related to things like Deinonychus and Utahraptor, and so birds are, by definition, part of the dinosaur¹ group.

　　鸟类的祖先与恐爪龙和犹他盗龙这类恐龙亲缘关系很近，所以从定义来说鸟类是恐龙族群的一部分。

　　So the dinosaur survived, but I have to say, all the really cool ones died out.

　　所以恐龙得以幸存，不过我得承认，真正有意思的都死光了。

　　This extinction⁴ event was not only distinctive⁵ for its speed, but the force of this blast is almost unimaginable.

　　这次灭绝事件不仅因为其发生速度而独特，而其摧毁力也几乎令人无法想象。

　　There are numerous kinds of extinction events.

　　历史上有过很多种灭绝事件。

　　Some can be local, where only a few plants and animal species are affected⁶.

　　有些是本地的，只影响几种植物和动物种类。

　　Some can be regional, where quite a few species get it.

　　有些是区域性的，涉及的物种数量就比较多。

　　And then there are those events that are so enormous, they make modern Hollywood effects look like an Ed Wood movie effect.

　　还有那些极大的事件，它们使得现代好莱坞特效看起来像是艾德·伍德（1994年的电影）电影效果。

　　Scientists were initially⁷ at a loss to explain how this could have happened.

　　科学家们开始时无法解释这是如何发生的。

　　One theory pointed⁸ to global warming.

　　一种理论指向全球变暖。

　　Climate change had probably been a major factor in the first dinosaur extinction, so it seemed a likely candidate in the second one.

　　在第一次恐龙灭绝事件中气候变化可能是主要原因，所以它似乎是第二次的嫌疑对象。

　　The fact that the blast impacted on land and sea creatures alike, seemed to support this theory.

　　这次灾难对陆地生物和海洋生物的影响相似，这似乎支持这种理论。

　　Extinction is actually worldwide, it's not just a terrestrial phenomena⁹, it doesn't occur just on land.

　　这次灭绝是全球性的，这不是陆地事件，它不仅发生在陆地上。

　　In fact most of the really spectacular extinctions have been based in the oceans.

　　其实很多非常惊人的物种灭绝都发生在海里。

　　So we have whole groups of animals which are simply not around today.

　　所以我们有很多类动物今天都无法见到了。

　　And extinction in the marine¹⁰ realm is really for the same reasons it occurs on land.

　　在海洋王国的灭绝其实和陆地上发生的原因一样。

　　In 1980, an unusually discovery would finally lift the veil of mystery.

　　在1980年，一个不寻常的发现最终揭开了谜团的面纱。

　　What Dr. Louis Alvarez, and his son, Dr. Walter Alvarez, uncovered set off a firestorm.

　　路易斯·阿尔弗雷兹博士和他儿子沃尔特·阿尔弗雷兹博士的发现，掀起了风暴。

　　In 1980, when Louis and Walter Alvarez were looking at the sedimentation¹¹ rates, they weren't really interested so much in the extinction of dinosaurs,

　　在1980年路易斯和沃尔特·阿尔弗雷兹当时在研究沉积速度，他们对恐龙灭绝并没多大兴趣，

　　they were looking at, measuring the rate of sedimentation of deep ocean sediments¹².

　　他们关注的是，对深海沉积物沉积速率的测量。

　　One particular little layer though, however, showed a whopping increase in the concentration of the metal Iridium.

　　但其中有一小层却表现出金属铱的高度富集。

　　And they calculated if you were to spread the amount of Iridium in this layer that adds up to a total amount of material about equivalent to a ten-kilometer diameter asteroid¹³.

　　他们计算过，要是把这一层里的铱的数量分散开来，那其材料总量就相当于一颗直径10千米的小行星。

　　A 10-kilometer asteroid, that's 6 miles wide - the size of Mount Everest.

　　直径10千米的小行星，那就是六英里宽，大小如同埃佛勒斯峰。

　　The reason why an asteroid was looked at as the cause of the Iridium spike¹⁴ at the K-T boundary, is because asteroids¹⁵ have an enormous amount of Iridium in them.

　　一颗小行星被看做是引起KT界限层铱猛增的原因，是因为小行星中有相当多的铱。

　　The earth has Iridium in it, but because it is a heavy metal, most of it settles towards the center of the planet.

　　地球也有铱，但因为它是重金属，多数都沉降到行星的中心。

　　But this thick layer of Iridium that separates the Cretaceous and Tertiary periods clearly was an anomaly and it had been deposited over a very short time.

　　但这个隔开了白垩纪和第三纪的厚铱层显然是个异常事物，而且它在很多的时间内便沉积下来。

　　But something else supported the asteroid theory.

　　还有其它证据支持小行星理论。

　　Along with the high levels of Iridium, they found something even more fascinating - shocked-quartz¹⁶.

　　除了高度富集的铱以外，他们还发现了更为奇妙的东西——冲击石英

　　Shocked-quarts is a form of quartz that has a very different structure.

　　冲击石英是石英的一种形式，有很不一样的结构。

　　Under incredible pressure, the crystals within the quarts are deformed¹⁷ and actually fractured.

　　在极高压下，石英的内部结晶变现破裂。

　　Well, under magnification, you can see these deformations¹⁸.

　　经过放大后就能看到这种变形。

　　There was only one other place where scientists had seen shocked-quartz - at the site of a nuclear bomb test that was conducted at the Alamogordon test range in New Mexico in 1945.

　　科学家们此前只在另外一处地方见过这种冲击石英 ，在一个核弹测试点，该核弹测试在1945年新墨西哥州的阿拉莫戈多试验场进行。

　　Shocked-quartz was first identified at the site of an underground nuclear bomb test.

　　冲击石英首次被确定是在一个地下核弹试验场。

　　It's that kind of force that causes this particular quartz to form,

　　正是那种巨大的力量导致了这种特殊石英的形成，

　　so finding shocked-quartz mixed within the high levels of Iridium was pretty darn clear evidence that something massive had hit the earth.

　　所以找到冲击石英加上高度富集的铱，就是相当确凿的证据，说明曾经有巨大物体撞击地球。

1 dinosaur   

n.恐龙

参考例句：

• Are you trying to tell me that David was attacked by a dinosaur?你是想要告诉我大卫被一支恐龙所攻击？
• He stared at the faithful miniature of the dinosaur.他凝视著精确的恐龙缩小模型。

2 dinosaurs   

n.恐龙( dinosaur的名词复数 )；守旧落伍的人，过时落后的东西

参考例句：

• The brontosaurus was one of the largest of all dinosaurs. 雷龙是所有恐龙中最大的一种。 来自《简明英汉词典》
• Dinosaurs have been extinct for millions of years. 恐龙绝种已有几百万年了。 来自《简明英汉词典》

3 dominant   

adj.支配的，统治的；占优势的；显性的；n.主因，要素，主要的人(或物)；显性基因

参考例句：

• The British were formerly dominant in India.英国人从前统治印度。
• She was a dominant figure in the French film industry.她在法国电影界是个举足轻重的人物。

4 extinction   

n.熄灭，消亡，消灭，灭绝，绝种

参考例句：

• The plant is now in danger of extinction.这种植物现在有绝种的危险。
• The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。

5 distinctive   

adj.特别的，有特色的，与众不同的

参考例句：

• She has a very distinctive way of walking.她走路的样子与别人很不相同。
• This bird has several distinctive features.这个鸟具有几种突出的特征。

6 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

7 initially   

adv.最初，开始

参考例句：

• The ban was initially opposed by the US.这一禁令首先遭到美国的反对。
• Feathers initially developed from insect scales.羽毛最初由昆虫的翅瓣演化而来。

8 pointed   

adj.尖的，直截了当的

参考例句：

• He gave me a very sharp pointed pencil.他给我一支削得非常尖的铅笔。
• She wished to show Mrs.John Dashwood by this pointed invitation to her brother.她想通过对达茨伍德夫人提出直截了当的邀请向她的哥哥表示出来。

9 phenomena   

n.现象

参考例句：

• Ade couldn't relate the phenomena with any theory he knew.艾德无法用他所知道的任何理论来解释这种现象。
• The object of these experiments was to find the connection,if any,between the two phenomena.这些实验的目的就是探索这两种现象之间的联系，如果存在着任何联系的话。

10 marine   

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

• Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

11 sedimentation   

n.沉淀，沉积

参考例句：

• Sedimentation, the damage of a breach are problems, too. 而且沉积和决口的问题，也是存在的。 来自英语晨读30分（高二）
• Sedimentation and denudation play a role in exceptional cases. 沉积和剥蚀作用的影响只在特殊情况下起作用。

12 sediments   

沉淀物( sediment的名词复数 )； 沉积物

参考例句：

• When deposited, 70-80% of the volume of muddy sediments may be water. 泥质沉积物沉积后，体积的70-80％是水。
• Oligocene erosion had truncated the sediments draped over the dome. 覆盖于穹丘上的沉积岩为渐新世侵蚀所截削。

13 asteroid   

n.小行星；海盘车(动物)

参考例句：

• Astronomers have yet to witness an asteroid impact with another planet.天文学家还没有目击过小行星撞击其它行星。
• It's very unlikely that an asteroid will crash into Earth but the danger exists.小行星撞地球的可能性很小，但这样的危险还是存在的。

14 spike   

n.长钉，钉鞋；v.以大钉钉牢，使...失效

参考例句：

• The spike pierced the receipts and held them in order.那个钉子穿过那些收据并使之按顺序排列。
• They'll do anything to spike the guns of the opposition.他们会使出各种手段来挫败对手。

15 asteroids   

n.小行星( asteroid的名词复数 )；海盘车，海星

参考例句：

• Asteroids,also known as "minor planets",are numerous in the outer space. 小行星，亦称为“小型行星”，在外太空中不计其数。
• Most stars probably have their quota of planets, meteorids, comets, and asteroids. 多数恒星也许还拥有若干行星、流星、彗星和小行星。

16 quartz   

n.石英

参考例句：

• There is a great deal quartz in those mountains.那些山里蕴藏着大量石英。
• The quartz watch keeps good time.石英表走时准。

17 deformed   

adj.畸形的；变形的；丑的，破相了的

参考例句：

• He was born with a deformed right leg.他出生时右腿畸形。
• His body was deformed by leprosy.他的身体因为麻风病变形了。

18 deformations   

损形( deformation的名词复数 )； 变形； 畸形； 破相

参考例句：

• It would make no difference if the bar deformations were totally inelastic. 如果杆的变形完全是非弹性变形时这也就没有什么区别了。
• Such readings can reveal longer-period deformations in the earth. 这种读数可以反映地球长周期的形变。