科学美国人60秒 SSS 鸭嘴兽的灭绝可能为我们揭开恐龙的最后时刻

This is Scientific American's 60-second Science, I'm Susanne Bard¹.

这里是科学美国人——60秒科学系列，我是苏珊娜·巴德。

In North America, fossils of duckbill dinosaur² are abundant.

在北美，鸭嘴兽的化石非常丰富。

So abundant that paleontologists sometimes ignore them in search of more exciting species, like T. Rex or Triceratops.

数量如此之多，以至于古生物学家有时会忽略它们，去寻找更令人兴奋的物种，比如霸王龙或三角龙。

“They were so common we often wouldn't collect them and just left them out in the field.”

“它们太常见了，我们通常不会收集它们的化石，而是把它们留在地里。”

University of Bath evolutionary³ biologist Nick Longrich.

巴斯大学进化生物学家尼克·隆瑞奇说。

But duckbills had never been found in Africa.

但在非洲从未发现过鸭嘴兽。

So, Longrich did a double take when he was visiting the Natural History Museum of Marrakesh in Morocco and came across the 66-million-year-old jawbone of a previously⁴ undocumented duckbill species.

因此，隆瑞奇在参观摩洛哥马拉喀什自然历史博物馆时多看了两眼，偶然发现了一块6600万年前的之前未记录在册的鸭嘴兽的颚骨。

“I instantly knew what it was, and I just couldn't figure out what it was doing there.”

“我立刻就知道它是什么，只是不知道它在那里做什么。”

Its presence in North Africa was problematic because during the Late Cretaceous period the planet was warmer, which means sea levels were higher.

它在北非的存在是有问题的，因为在白垩纪晚期，地球更温暖，这意味着海平面更高。

“Africa was isolated⁵ from all the other continents by water, and there didn't seem to be any way that they could get there.”

“非洲与其他大陆被海水隔离开来，他们似乎没有任何办法可以到达那里。”

Unless, perhaps, duckbills swam hundreds of miles across open ocean from what is now Europe.

除非鸭嘴兽从现在的欧洲游几百英里穿过广阔的海洋。

It's not as far-fetched as it might sound.

这并不像听起来的那么牵强。

In fact, paleontologists once thought duckbill dinosaurs⁶ were aquatic⁷, but that theory eventually fell out of favor.

事实上，古生物学家曾经认为鸭嘴恐龙是水生动物，但这个理论最终失宠了。

Nonetheless, there's evidence that duckbills were well-adapted for swimming.

尽管如此，有证据表明，鸭嘴兽很适合游泳。

“They have these really big, powerful hind⁸ limbs. Great big feet.

“它们有非常大、有力的后肢。有巨大的脚掌。

They've got a long, deep tail they could have used for sculling.

它们有一条又长又厚的尾巴，可以用来划水。

So, they might have been pretty good swimmers.”

所以，他们可能是很好的游泳者。”

Plus, other animal species have been known to cross oceans, albeit⁹ rarely.

此外，其他动物物种也曾横渡海洋，尽管很少。

Elephants, monkeys, and even hippos, for example, have all colonized¹⁰ new places after swimming or floating there.

例如，大象、猴子，甚至河马，游到或漂浮到新的地方后，都在那里定居。

“It's incredibly improbable. But over millions of years, these once-in-a-million-year events will happen on average once every million years.”

“这是非常不可能的。 但在数百万年的时间里，这种百万年一次的事件平均每百万年发生一次。”

To better understand the migrations¹¹ of duckbill dinosaurs, Longrich and his colleagues reconstructed their evolutionary tree.

为了更好地理解鸭嘴龙的迁徙，隆瑞奇和他的同事重建了他们的进化树。

“The duckbills seem to originate in North America.

“鸭嘴兽似乎起源于北美。

They migrate across the land bridge into Asia, jump over into Europe.

他们跨过陆桥，进入亚洲，然后进入欧洲。

And then finally this European lineage, one branch of that evolutionary tree, jumps into Africa.”

最后，这个欧洲世系，进化树的一个分支，进入了非洲。”

Longrich's team dubbed¹² the new species Ajnabia odysseus.

隆瑞奇的研究小组将这种新物种命名为奥式异域龙。

Some duckbills were 50-feet long, but Ajnabia was perhaps the smallest of these Cretaceous vegetarians¹³, about the size of a pony¹⁴.

有些鸭嘴兽有50英尺长，但异域龙可能是白垩纪最小的素食者，只有小马那么大。

And while North American duckbills were being hunted down by hungry T. rex, in Africa, Ajnabia likely had to contend with fearsome Abelisaurs, which were smaller, but similar to T. rex.

当北美的鸭嘴兽在非洲被饥饿的霸王龙猎杀时，异域龙可能不得不与可怕的阿贝尔龙搏斗，它体型较小，但与霸王龙相似。

The study is in the journal Cretaceous Research.

这项研究发表在《白垩纪研究》杂志上。

Insights into Ajnabia could help answer questions about the end of the age of the dinosaurs.

对异域龙的深入了解有助于回答有关恐龙时代结束的问题。

“This is just before the asteroid¹⁵ hit.

“就在小行星撞击地球之前。

So, we're getting a snapshot of the dinosaurs in their final moments.

所以，我们得到了恐龙最后时刻的大致情况。

The sort of twilight¹⁶ of the dinosaurs.

恐龙的衰退期。

Along with things like T-Rex and Triceratops, these were the last dinosaurs on earth.”

与霸王龙和三角龙一样，它们是地球上最后的恐龙。”

Thanks for listening for Scientific American's 60-second Science. I'm Susanne Bard.

谢谢大家收听科学美国人——60秒科学。我是苏珊娜·巴德。

1 bard   

n.吟游诗人

参考例句：

• I'll use my bard song to help you concentrate!我会用我的吟游诗人歌曲帮你集中精神！
• I find him,the wandering grey bard.我发现了正在徘徊的衰老游唱诗人。

2 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。

3 evolutionary   

adj.进化的；演化的，演变的；[生]进化论的

参考例句：

• Life has its own evolutionary process.生命有其自身的进化过程。
• These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。

4 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

5 isolated   

adj.与世隔绝的

参考例句：

• His bad behaviour was just an isolated incident. 他的不良行为只是个别事件。
• Patients with the disease should be isolated. 这种病的患者应予以隔离。

6 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》

7 aquatic   

adj.水生的，水栖的

参考例句：

• Aquatic sports include swimming and rowing.水上运动包括游泳和划船。
• We visited an aquatic city in Italy.我们在意大利访问过一个水上城市。

8 hind   

adj.后面的，后部的

参考例句：

• The animal is able to stand up on its hind limbs.这种动物能够用后肢站立。
• Don't hind her in her studies.不要在学业上扯她后腿。

9 albeit   

conj.即使；纵使；虽然

参考例句：

• Albeit fictional,she seemed to have resolved the problem.虽然是虚构的，但是在她看来好象是解决了问题。
• Albeit he has failed twice,he is not discouraged.虽然失败了两次，但他并没有气馁。

10 colonized   

开拓殖民地，移民于殖民地( colonize的过去式和过去分词 )

参考例句：

• The area was colonized by the Vikings. 这一地区曾沦为维京人的殖民地。
• The British and French colonized the Americas. 英国人和法国人共同在美洲建立殖民地。

11 migrations   

n.迁移，移居( migration的名词复数 )

参考例句：

• It foundered during the turmoils accompanying the Great Migrations. 它在随着民族大迁徙而出现的混乱中崩溃。 来自辞典例句
• Birds also have built-in timepieces which send them off on fall and spring migrations. 鸟类也有天生的时间感应器指导它们秋春迁移。 来自互联网

12 dubbed   

v.给…起绰号( dub的过去式和过去分词 )；把…称为；配音；复制

参考例句：

• Mathematics was once dubbed the handmaiden of the sciences. 数学曾一度被视为各门科学的基础。
• Is the movie dubbed or does it have subtitles? 这部电影是配音的还是打字幕的？ 来自《简明英汉词典》

13 vegetarians   

n.吃素的人( vegetarian的名词复数 )；素食者；素食主义者；食草动物

参考例句：

• Vegetarians are no longer dismissed as cranks. 素食者不再被视为有怪癖的人。
• Vegetarians believe that eating meat is bad karma. 素食者认为吃肉食是造恶业。

14 pony   

adj.小型的；n.小马

参考例句：

• His father gave him a pony as a Christmas present.他父亲给了他一匹小马驹作为圣诞礼物。
• They made him pony up the money he owed.他们逼他还债。

15 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。

16 twilight   

n.暮光，黄昏；暮年，晚期，衰落时期

参考例句：

• Twilight merged into darkness.夕阳的光辉融于黑暗中。
• Twilight was sweet with the smell of lilac and freshly turned earth.薄暮充满紫丁香和新翻耕的泥土的香味。