经济学人304:海豹如何享用它的午餐

　　Science and technology

　　科学技术

　　How leopard¹ seals lunch

　　海豹如何享用它的午餐

　　Suck, swish, gulp²

　　吸，吮，咽

　　Eating big and little

　　大小通吃

　　JUST about every place on the planet has a predator³ at the top of the food web.

　　地球上每个地方都有一个处于食物网顶端的捕食者。

　　The African savannahs have the lion, the jungles of Asia the tiger and the arctic tundra⁴ the polar bear.

　　比如非洲大草原上的狮子，亚洲丛林里的老虎以及北极冻原上的北极熊。

　　In the Antarctic it is the leopard seals who dominate as voracious⁵ hunters of penguins⁶ and other seal species.

　　而南极的霸主则是那些贪婪地捕食着企鹅和其他海豹种群的豹海豹。

　　But a new study examining their feeding habits led by David Hocking of Monash University in Australia, has revealed something unusual:

　　但是一个验证豹海豹进食习惯的新研究显示了一些不寻常的东西：

　　how leopard seals use an efficient filter-feeding system to eat near the bottom of the food chain too.

　　那就是豹海豹如何利用一个高效的食物过滤系统同时享用靠近食物链底端的生物。来自澳大利亚蒙纳什大学的大卫霍金是此项研究的负责人。

　　Researchers have long known that a sizeable portion of the seals’ diet is made up of krill.

　　研究者们很早就知道在豹海豹的食谱中一大部分是由磷虾组成。

　　But exactly how they consume these tiny crustaceans⁷ has been a mystery as the seals’ mouths have large sharp teeth that seemed utterly⁸ inappropriate for capturing them.

　　但是由于豹海豹嘴里的尖牙似乎完全不适合捕捉这些磷虾，从而它们是如何享用这些微小的甲壳类生物便成了一个迷。

　　Some researchers have theorised that the seals might suck water into their mouths and swish it past their closed teeth to capture krill.

　　一些研究者们从理论角度分析豹海豹也许可以通过先入吸海水再闭紧牙齿将海水吐出的筛选法捕捉磷虾。

　　But such behaviour depends upon leopard seals being able to suck up food from water, a specialised feeding behaviour that is rarely seen in top predators⁹.

　　但是完成这些动作需要豹海豹具备从海水中吸吮食物的能力，而这种特定的进食行为在位于食物链顶端的捕食者身上并不常见。

　　Keen to explore this, Mr Hocking turned his attention towards Casey and Sabine, two leopard seals at the Taronga Zoo in Sydney.

　　热衷于探索这一问题的霍金先生将注意力转向了凯西和萨宾这两只悉尼塔龙加动物园的豹海豹身上。

　　He and his colleagues designed a clear plastic box with thin tubes in which fish could be placed.

　　他和同事们设计了一种透明的塑料盒子，里面安装了可以盛放鱼的浅的管道。

　　The seals could not get at them with their teeth, and instead sucked the fish right out of the tubes.

　　豹海豹无法用它的牙齿来取食这些鱼，而是从管道中把它们吸出来。

　　Moments later, the team saw clouds of murky¹⁰ water and bubbles being expelled from the sides of the seals’ mouths.

　　过了一会，研究小组发现一团一团的浑浊的水体和泡沫从豹海豹的嘴里喷出。

　　This, they realised, was a filter-feeding system in action.

　　研究者们意识到，这表示一套进食过滤系统正在工作。

　　In examining the wear on the teeth of skulls¹¹ from wild leopard seals, Mr Hocking was able to work out which teeth the seals were using to filter out tiny prey¹².

　　在检查野生豹海豹颅骨上牙齿的磨损度时，霍金先生弄明白了豹海豹是用哪些牙齿来过滤出微小猎物的。

　　He found extensive abrasions¹³ on canines¹⁴ and incisors, the sharp teeth at the front of their mouths.

　　他发现位于口腔前端的那些锋利的犬齿和门齿上存在大面积磨损的情况。

　　This, Mr Hocking points out in Polar Biology, indicates that these teeth are used to chomp¹⁵ penguins and other seals.

　　霍金先生在《极地生物》杂志上指出，这表明豹海豹利用这些牙齿来撕咬企鹅和其他海豹。

　　But since there is no such wear on the sharp and delicate postcanines, he believes that although these triangular¹⁶ rear teeth look fierce, when closed they form a sieve¹⁷ that is the perfect size for filtering.

　　但是，由于在锋利而精致的犬齿后齿上并没有发现磨损的情况，他认为尽管这些三角形的后槽牙看上去非常凶狠，但是当咬合时，它们可以充当一个对于过滤事物来说其尺寸可谓完美的筛子。

　　Ideal dentistry, if you like, for a mixed diet.

　　如果你乐意，这是一套进行混合膳食的理想的牙科学。

　　1.food chain 食物链

　　Officials also say it never entered the human food chain.

　　官员称它从未进入人类的食物链当中。

　　Mercury accumulates as it works its way up the food chain.

　　汞会随着食物链上的食物传递而积聚。

　　2.made up of 由…组成，由…构成

　　The fill made up of basket loads of different colored clay.

　　填充物由一篮一篮不同色的粘土形成。

　　The brain is made up of cells in a certain arrangement.

　　人脑是由细胞按一定的排列方式组成的。

　　3.suck up 吸收

　　Another way would be growing algae¹⁸ in the ocean to suck up carbon dioxide.

　　另外一种办法是可以通过在海洋里种植藻类来吸收二氧化碳。

　　The nutrients¹⁹ feed algal blooms, which suck up the oxygen in the water.

　　这些营养养育了大量藻类，这些藻类吸收水中的氧气。

　　4.work out 解决；作出；锻炼

　　Negotiators are due to meet later today to work out a compromise.

　　谈判人员定于今天晚些时候进行会谈，商定一个折中方案。

　　It took me some time to work out what was causing this.

　　我花了一些时间才弄清此事的起因。

1 leopard   

n.豹

参考例句：

• I saw a man in a leopard skin yesterday.我昨天看见一个穿着豹皮的男人。
• The leopard's skin is marked with black spots.豹皮上有黑色斑点。

2 gulp   

vt.吞咽，大口地吸（气）；vi.哽住；n.吞咽

参考例句：

• She took down the tablets in one gulp.她把那些药片一口吞了下去。
• Don't gulp your food,chew it before you swallow it.吃东西不要狼吞虎咽，要嚼碎了再咽下去。

3 predator   

n.捕食其它动物的动物；捕食者

参考例句：

• The final part of this chapter was devoted to a brief summary of predator species.本章最后部分简要总结了食肉动物。
• Komodo dragon is the largest living lizard and a fearsome predator.科摩多龙是目前存在的最大蜥蜴，它是一种令人恐惧的捕食性动物。

4 tundra   

n.苔原，冻土地带

参考例句：

• The arctic tundra is at the top of the world around the North Pole.北极冻原是指北极点周边的地区，是世界最高的地方。
• There is a large amount of methane gas under the Siberian tundra.西伯利亚的冻土地带之下有大量的甲烷气体。

5 voracious   

adj.狼吞虎咽的，贪婪的

参考例句：

• She's a voracious reader of all kinds of love stories.什么样的爱情故事她都百看不厌。
• Joseph Smith was a voracious book collector.约瑟夫·史密斯是个如饥似渴的藏书家。

6 penguins   

n.企鹅( penguin的名词复数 )

参考例句：

• Why can penguins live in cold environment? 为什么企鹅能生活在寒冷的环境中？ 来自《简明英汉词典》
• Whales, seals, penguins, and turtles have flippers. 鲸、海豹，企鹅和海龟均有鳍形肢。 来自《现代英汉综合大词典》

7 crustaceans   

n.甲壳纲动物（如蟹、龙虾）( crustacean的名词复数 )

参考例句：

• These crustaceans provide a valuable food source for some fish. 这些甲壳纲动物是某些鱼类重要的食物来源。 来自《简明英汉词典》
• When the tide ebbs it's a rock pool inhabited by crustaceans. 退潮时，它便成为甲壳动物居住的岩石区潮水潭。 来自辞典例句

8 utterly   

adv.完全地，绝对地

参考例句：

• Utterly devoted to the people,he gave his life in saving his patients.他忠于人民，把毕生精力用于挽救患者的生命。
• I was utterly ravished by the way she smiled.她的微笑使我完全陶醉了。

9 predators   

n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）

参考例句：

• birds and their earthbound predators 鸟和地面上捕食它们的动物
• The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》

10 murky   

adj.黑暗的，朦胧的；adv.阴暗地，混浊地；n.阴暗；昏暗

参考例句：

• She threw it into the river's murky depths.她把它扔进了混浊的河水深处。
• She had a decidedly murky past.她的历史背景令人捉摸不透。

11 skulls   

颅骨( skull的名词复数 )； 脑袋； 脑子； 脑瓜

参考例句：

• One of the women's skulls found exceeds in capacity that of the average man of today. 现已发现的女性颅骨中，其中有一个的脑容量超过了今天的普通男子。
• We could make a whole plain white with skulls in the moonlight! 我们便能令月光下的平原变白，遍布白色的骷髅！

12 prey   

n.被掠食者，牺牲者，掠食；v.捕食，掠夺，折磨

参考例句：

• Stronger animals prey on weaker ones.弱肉强食。
• The lion was hunting for its prey.狮子在寻找猎物。

13 abrasions   

n.磨损( abrasion的名词复数 )；擦伤处；摩擦；磨蚀（作用）

参考例句：

• He suffered cuts and abrasions to the face. 他的脸上有许多划伤和擦伤。
• The bacteria get into humans through abrasions in the skin. 细菌可以通过擦伤处进入人体。 来自《简明英汉词典》

14 canines   

n.犬齿( canine的名词复数 )；犬牙；犬科动物

参考例句：

• For example, the teeth are more primitive. There are large canines and unusually shaped incisors. 譬如，牙齿更为原始，有大的犬齿和非常合适的门齿。 来自辞典例句
• Well-to-canines can attend doggy daycare centers while their owners work. 富人家的狗在主人上班的时候可以去狗狗托管中心。 来自互联网

15 chomp   

v. （人、动物进食时）大声地咬，嚼得很响

参考例句：

• I lost a tooth while chomping on a French baguette!我啃法棍面包时，崩掉了一颗牙！
• They just chomp on tundra, nap a few hours and feast again.它们只是在苔原上大嚼特嚼，睡上几小时，接着再吃。

16 triangular   

adj.三角（形）的，三者间的

参考例句：

• It's more or less triangular plot of land.这块地略成三角形。
• One particular triangular relationship became the model of Simone's first novel.一段特殊的三角关系成了西蒙娜第一本小说的原型。

17 sieve   

n.筛，滤器，漏勺

参考例句：

• We often shake flour through a sieve.我们经常用筛子筛面粉。
• Finally,it is like drawing water with a sieve.到头来，竹篮打水一场空。

18 algae   

n.水藻，海藻

参考例句：

• Most algae live in water.多数藻类生长在水中。
• Algae grow and spread quickly in the lake.湖中水藻滋蔓。

19 nutrients   

n.（食品或化学品）营养物，营养品( nutrient的名词复数 )

参考例句：

• a lack of essential nutrients 基本营养的缺乏
• Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》