2020年经济学人 进化意外造就的杀手(1)

Funnel-web spiders have a fearsome reputation. People bitten by these Australian arachnids suffer extreme pain,

漏斗网蜘蛛有着一个可怕的名声。被这些澳大利亚蛛形纲动物叮咬过的人都会出现极度疼痛、

breathing problems, confusion, convulsions and dangerously high blood pressure. Left untreated, the venom¹ can kill within hours.

呼吸困难、精神混乱、抽搐和高危血压的症状。如果不进行治疗，毒液可以在数小时内致命。

For years, researchers assumed this lethal² effect was an evolutionary³ accident.

多年来，研究人员一直认为这种杀伤作用是进化的意外。

The venom, they presumed, evolved to help the spiders kill their prey⁴— normally insects.

他们推测这些毒液的进化是为了帮助蜘蛛杀死它们的猎物——通常是昆虫。

Killing⁵ mammals was either just collateral⁶ damage or a form of protection against possible predators⁸.

杀死哺乳类动物要么只是一种附带损伤，要么是一种防御潜在捕食者的形式。

Except that the venom does not, in general, kill mammals. Dogs, cats, mice, rabbits and guinea pigs all shake it off.

不过，这种毒液一般不会杀死哺乳动物。狗、猫、老鼠、兔子和豚鼠都会把它给抖掉。

It is only human beings and other primates¹⁰ that succumb¹¹. And there is another odd thing about it.

受到伤害的只有人类和其他灵长类动物。还有另一件奇怪的事情。

Funnel-web-spider venom has thousands of components¹², but delta-hexatoxins, the specific molecules¹⁴ within it that kill people,

漏斗网蜘蛛的毒液中含有数千种成分，但delta-hexatoxins，毒液中的这种致人死亡的特殊分子

are produced in particularly large quantities by sexually mature males during the breeding season—a time when they are barely feeding at all.

由在繁殖期性成熟的雄性蜘蛛大量生产——在此期间，它们几乎不进食。

Putting these various facts together has led Bryan Fry of the University of Queensland to suggest,

所有这些事实让昆士兰大学的Bryan Fry在发表于《Proceedings¹⁵ of the National Academy of Sciences》

in a paper published in the Proceedings of the National Academy of Sciences,

的一篇论文中提出了这样的观点，

that the role of delta-hexatoxins in funnel-web venom is not to kill prey but rather as a sophisticated form of defence—

在漏斗网蜘蛛的毒液中，delta-hexatoxins的作用不是杀死猎物，而是充当着一种复杂的防御形式——

and that, paradoxically, its deadliness to humans is because neither they nor their primate⁹ ancestors were, until recently, a threat to the spiders.

奇怪的是，它们对人类的致命性，既不是因为他们，也不是因为他们的灵长类动物祖先对蜘蛛构成了威胁。

Prey animals routinely attacked by venomous predators are under powerful pressure from natural selection.

经常被有毒捕食者袭击的猎物都承受着来自自然选择的巨大压力。

Any mutation¹⁶ which confers resistance to the venom will spread. This puts evolutionary pressure back onto the predator⁷,

任何能抵抗毒液的突变都会扩散。这给捕食者带来了进化压力，

encouraging the emergence¹⁷ of more potent¹⁸ venoms¹⁹, which encourages further resistance and provokes further potency²⁰.

鼓励了更强效毒液的出现，从而进一步鼓励其耐药性，激发更强的效力。

And so on. Toxins¹³ directed against prey thus evolve rapidly.

等等。因此针对猎物的毒素迅速进化。

That, though, is not true for defensive²¹ venoms. Taking a single type of spider off its menu

然而，防御性毒液却不是这样。将一种类型的蜘蛛除名

diminishes a predator's potential to survive and reproduce only slightly.

只会略微降低捕食者生存和繁殖的潜力。

1 venom   

n.毒液，恶毒，痛恨

参考例句：

• The snake injects the venom immediately after biting its prey.毒蛇咬住猎物之后马上注入毒液。
• In fact,some components of the venom may benefit human health.事实上，毒液的某些成分可能有益于人类健康。

2 lethal   

adj.致死的；毁灭性的

参考例句：

• A hammer can be a lethal weapon.铁锤可以是致命的武器。
• She took a lethal amount of poison and died.她服了致命剂量的毒药死了。

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 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。

5 killing   

n.巨额利润；突然赚大钱，发大财

参考例句：

• Investors are set to make a killing from the sell-off.投资者准备清仓以便大赚一笔。
• Last week my brother made a killing on Wall Street.上个周我兄弟在华尔街赚了一大笔。

6 collateral   

adj.平行的；旁系的；n.担保品

参考例句：

• Many people use personal assets as collateral for small business loans.很多人把个人财产用作小额商业贷款的抵押品。
• Most people here cannot borrow from banks because they lack collateral.由于拿不出东西作为抵押，这里大部分人无法从银行贷款。

7 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。

8 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》

9 primate   

n.灵长类（目）动物，首席主教；adj.首要的

参考例句：

• 14 percent of primate species are highly endangered.14%的灵长类物种处于高度濒危状态。
• The woolly spider monkey is the largest primate in the Americas.绒毛蛛猴是美洲最大的灵长类动物。

10 primates   

primate的复数

参考例句：

• Primates are alert, inquisitive animals. 灵长目动物是机灵、好奇的动物。
• Consciousness or cerebration has been said to have emerged in the evolution of higher primates. 据说意识或思考在较高级灵长类的进化中已出现。

11 succumb   

v.屈服，屈从；死

参考例句：

• They will never succumb to the enemies.他们决不向敌人屈服。
• Will business leaders succumb to these ideas?商业领袖们会被这些观点折服吗？

12 components   

（机器、设备等的）构成要素，零件，成分； 成分( component的名词复数 )； [物理化学]组分； [数学]分量； （混合物的）组成部分

参考例句：

• the components of a machine 机器部件
• Our chemistry teacher often reduces a compound to its components in lab. 在实验室中化学老师常把化合物分解为各种成分。

13 toxins   

n.毒素( toxin的名词复数 )

参考例句：

• The seas have been used as a receptacle for a range of industrial toxins. 海洋成了各种有毒工业废料的大容器。
• Most toxins are naturally excreted from the body. 大部分毒素被自然排出体外。 来自《简明英汉词典》

14 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

15 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼

16 mutation   

n.变化，变异，转变

参考例句：

• People who have this mutation need less sleep than others.有这种突变的人需要的睡眠比其他人少。
• So far the discussion has centered entirely around mutation in the strict sense.到目前为止，严格来讲，讨论完全集中于围绕突变问题上。

17 emergence   

n.浮现，显现，出现，（植物）突出体

参考例句：

• The last decade saw the emergence of a dynamic economy.最近10年见证了经济增长的姿态。
• Language emerges and develops with the emergence and development of society.语言是随着社会的产生而产生，随着社会的发展而发展的。

18 potent   

adj.强有力的，有权势的；有效力的

参考例句：

• The medicine had a potent effect on your disease.这药物对你的病疗效很大。
• We must account of his potent influence.我们必须考虑他的强有力的影响。

19 venoms   

n.（某些蛇、蝎子等分泌的）毒液( venom的名词复数 )；愤恨的感情或语言；毒物

参考例句：

• Spider venoms are exquisitely refined to interfere with the nervous systems of insects. 蜘蛛的毒液非常微妙，专门损坏昆虫的神经系统。 来自百科语句
• Venoms (especially upgraded) are the ideal unit for taking out husks. 毒液（特别是升级后的）是消灭外壳的理想单位。 来自互联网

20 potency   

n. 效力，潜能

参考例句：

• Alcohol increases the drug's potency.酒精能增加这种毒品的效力。
• Sunscreen can lose its potency if left over winter in the bathroom cabinet.如果把防晒霜在盥洗室的壁橱里放一个冬天，就有可能失效。

21 defensive   

adj.防御的；防卫的；防守的

参考例句：

• Their questions about the money put her on the defensive.他们问到钱的问题，使她警觉起来。
• The Government hastily organized defensive measures against the raids.政府急忙布置了防卫措施抵御空袭。