标题：进化意外造就的杀手（1）

来源：每日英语听力，经济学人-科技（The Economist-Science and technology)

Summary

    Funnel-web spiders have beaten many people in Australian and the venom would lead to great suffer and even death in hours without treatment. It was assumed as a defensive tool when bleeding season, and general mammals can shake it out. But recently the assumption was broken down by a published research suggesting that it was the result of natural selection used to prey insects. Since predators evolve more fatal traits, the weaker can only save through developing more potent tools.

单词积累

funnel    n.    1.漏斗    2.（蒸汽机车或轮船上的）烟囱

               v.[i][t]（使）流经狭窄空间，经过漏斗形口子

fearsome    adj.    很可怕的；十分吓人的making people feel very frightened

venom    n.    1.（毒蛇、蜘蛛等分泌的）毒液

                        2.恶毒；怨恨；恶意；歹心strong bitter feeling; hatred and a desire to hurt sb

venomous    adj.    1.分泌毒液的；有毒的producing venom

                                2.恶毒的；恶意的；充满仇恨的full of bitter feeling or hatred

toxin    n.    毒素（尤指生物体内细菌产生的毒物）a poisonous substance, especially one that is produced by bacteria in plants and animals

lethal    adj.    1.致命的；可致死的causing or able to cause death

                        2.(informal)危害极大的；破坏性极大的causing or able to cause a lot of harm or damage

presume  推测

prey    猎物    predator 捕食者

collateral    n.[u]    抵押物；担保品property or sth valuable that you promise to give to sb if you cannot pay back money that you borrow

                    adj.    附属的；附加的；附带的connected with sth else, but in addition to it and less important

succumb    v.    屈服；屈从；抵挡不住（攻击、疾病、诱惑等）to not be able to fight an attack, an illness, a temptation , etc.

sophisticated    adj.

1.见多识广的；老练的；见过世面的having a lot of experience of the world and knowing about fashion, culture and other things that people think are socially important

2.复杂巧妙的；先进的；精密的clever and complicated in the way that it works or is presented

3.水平高的；在行的able to understand difficult or complicated ideas

paradoxically  adv.     自相矛盾地；荒谬地；矛盾的

  used for saying that something is strange because it is the opposite of what you expect

mutation    n.

1.[u][c]（生物物种的）突变，变异a process in which the genetic material of a person, a plant or an animal changes in structure when it is passed on to children, etc., causing different physical characteristics to develop; a change of this kind

2.[u][c]（形式或结构的）转变，改变a change in the form or structure of sth

confer    v.    1.[i]confer (with sb) (on/about sth)    商讨；协商；交换意见

                                    to discuss sth with sb, in order to exchange opinions or get advice

                      2.[t]confer sth (on/upon sb)授予，颁发（奖项、学位、荣誉或权利）

                                    to give sb an award, a university degree or a particular honour or right

resistance to

potent    adj.

1.有强效的；有力的；烈性的；影响身心的having a strong effect on your body or mind

2.强大的；强有力的powerful

原文表达

Funnel-web spiders have a fearsome reputation.漏斗网蜘蛛有着一个可怕的名声。 

People bitten by these Australian arachnids suffer extreme pain, breathing problems, confusion, convulsions and dangerously high blood pressure. 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、呼吸困难、精神混乱、抽搐和高危血压的症状。

Left untreated, the venom can kill within hours.如果不进行治疗，毒液可以在数小时内致命。

convulsion    n.

1.痉挛；抽搐a sudden shaking movement of the body that cannot be controlled

2.动乱；骚动a sudden important change that happens to a country or an organization

For years, researchers assumed this lethal effect was an evolutionary 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 prey-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。

Killing mammals was either just collateral damage or a form of protection against possible predators.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.不过，这种毒液一般不会杀死哺乳动物。

Dogs, cats, mice, rabbits and guinea pigs all shake it off.狗、猫、老鼠、兔子和豚鼠都会把它给抖掉。

It is only human beings and other primates that succumb.受到伤害的只有人类和其他灵长类动物。

And there is another odd thing about it.还有另一件奇怪的事情。

primates    n.1.灵长类    2.【动物;动物学】灵长目〔包括人、猿等〕

Funnel-web-spider venom has thousands of components, but delta-hexatoxins, the specific molecules within it that kill people, are produced in particularly large quantities by sexualy mature males during the breeding season-a time when they are barely feeding at all.漏斗网蜘蛛的毒液中含有数干种成分，但delta-hexatoxins,毒液中的这种致人死亡的特殊分子，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, in a paper published in the Proceedings of the National Academy of Sciences, that the role of delta-hexatoxins in funnel-web venom is not to kill prey but rather as a sophisticated form of defence - and that, paradoxically, its deadliness to humans is because neither they nor their primate ancestors were, until recently, a threat to the spiders.

所有这些事实让昆士兰大学的Bryan Fry在发表于《Proceedings of the National Academy of Sciences》的一篇论文中提出了这样的观点，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——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 mutation which confers resistance to the venom will spread. This puts evolutionary pressure back onto the predator, encouraging the emergence of more potent venoms, which encourages further resistance and provokes further potency.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，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. Toxins 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 defensive venoms. Taking a single type of spider off its menu diminishes a predator's potential to survive and reproduce only slightly.然而，防御性毒液却不是这样。将一种类型的蜘蛛除名只会略微降低捕食者生存和繁殖的潜力。

diminish    v.

1.[i][t]diminish (sth)减少；（使）减弱，缩减；降低to become or to make sth become smaller, weaker, etc.

2.[t]diminish sb/sth贬低；贬损；轻视to make sb/sth seem less important than they really are