万物简史 第275期:砰!(10)

 　　While Gene¹ Shoemaker was trying to get people galvanized about the potential dangers of the inner solar system, 正当尤金·苏梅克试图提醒人们注意太阳系内部的潜在危险的时候，

　　another development—wholly unrelated on the face of it, 另一件大事——表面看来完全没有关系，

　　was quietly unfolding in Italy with the work of a young geologist² from the Lamont Doherty Laboratory at Columbia University. 在意大利悄悄揭开序幕，由于哥伦比亚大学莱蒙特·多赫蒂实验室的一位年轻地质学家的工作。

　　In the early 1970s, Walter Alvarez was doing fieldwork in a comely³ defile⁴ known as the Bottaccione Gorge⁵, near the Umbrian hill town of Gubbio, 20世纪70年代初，在距离翁布里亚地区的山城古比奥不远的地方，沃尔特·阿尔瓦雷斯正在一个名叫博塔西昂峡谷的峡道里作实地考察。

　　when he grew curious about a thin band of reddish clay that divided two ancient layers of limestone⁶, 他突然对薄薄的一层淡红色黏土发生了兴趣。

　　one from the Cretaceous period, the other from the Tertiary. 这层黏土把古代灰岩分为两层，一层属于白垩纪，一层属于第三纪。

　　This is a point known to geology as the KT boundary, and it marks the time, sixty-five million years ago, 这在地质学里被称之为KT界线。它标志着6500万年前

　　when the dinosaurs⁸ and roughly half the world's other species of animals abruptly⁹ vanish from the fossil record. 恐龙和世界上大约一半其他种类的动物从化石记录中突然消失。

　　It is KT rather than CT because C had already been appropriated for Cambrian. 是KT界线，而不是CT界线，因为C已经用来代表“寒武纪”。

　　Depending on which source you credit, the K comes either from the Greek Kreta or German Kreide. K不是来自希腊语Kreta，就是来自德语Kreide。

　　Both conveniently mean "chalk," which is also what Cretaceous means. 二者的意思都是白垩，这也是“白垩纪”的意思。

　　Alvarez wondered what it was about a thin lamina of clay, barely a quarter of an inch thick, 阿尔瓦雷斯不大明白，只有6毫米左右厚的薄薄一层黏土，

　　that could account for such a dramatic moment in Earth's history. 怎么能说明地球史上这么个戏剧性的时刻。

　　At the time the conventional wisdom about the dinosaur⁷ extinction¹⁰ was the same as it had been in Charles Lyell's day a century earlier, 当时，关于恐龙灭绝的时间，人们通常的看法与一个世纪前查尔斯·莱尔时代一样，

　　namely that the dinosaurs had died out over millions of years. 即恐龙灭绝于几百万年以前。

1 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

2 geologist   

n.地质学家

参考例句：

• The geologist found many uncovered fossils in the valley.在那山谷里，地质学家发现了许多裸露的化石。
• He was a geologist,rated by his cronies as the best in the business.他是一位地质学家，被他的老朋友们看做是这门行当中最好的一位。

3 comely   

adj.漂亮的，合宜的

参考例句：

• His wife is a comely young woman.他的妻子是一个美丽的少妇。
• A nervous,comely-dressed little girl stepped out.一个紧张不安、衣着漂亮的小姑娘站了出来。

4 defile   

v.弄污，弄脏；n.(山间)小道

参考例句：

• Don't defile the land of our ancestors!再不要污染我们先祖们的大地！
• We respect the faith of Islam, even as we fight those whose actions defile that faith.我们尊重伊斯兰教的信仰，并与玷污伊斯兰教的信仰的行为作斗争。

5 gorge   

n.咽喉，胃，暴食，山峡；v.塞饱，狼吞虎咽地吃

参考例句：

• East of the gorge leveled out.峡谷东面地势变得平坦起来。
• It made my gorge rise to hear the news.这消息令我作呕。

6 limestone   

n.石灰石

参考例句：

• Limestone is often used in building construction.石灰岩常用于建筑。
• Cement is made from limestone.水泥是由石灰石制成的。

7 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。

8 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》

9 abruptly   

adv.突然地，出其不意地

参考例句：

• He gestured abruptly for Virginia to get in the car.他粗鲁地示意弗吉尼亚上车。
• I was abruptly notified that a half-hour speech was expected of me.我突然被通知要讲半个小时的话。

10 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。