经济学人309:节肢动物学 情人为食

 　　Science and technology

　　科学技术

　　Arachnology

　　节肢动物学

　　Having a mate for dinner

　　情人为食

　　Male spiders make the supreme¹ sacrifice for their children

　　雄蛛对后代的无私奉献

　　AMONG spiders, the female of the species really is more deadly than the male.

　　蜘蛛家族中,雌蛛致命性比雄蛛高得多。交配后将配偶狼吞虎咽地吃掉，雌蛛因此声名在外。

　　Lady arachnids have a well-deserved reputation for polishing off their suitors, post copula, in a manner that Hannibal Lecter might have admired.

　　它们的这一行为或许在一定程度上赢得了汉尼拔莱克特的敬仰，

　　But it has never been clear why this happens.

　　然而其原因一直不为人所知。

　　Some biologists believe it is simply a mixture of female hunger and the availability of a meal that is in no position to run away.

　　一些生物学家认为这仅仅是因为雌蛛饿了，而盘中餐又无力逃脱。

　　Others suspect that the male is actually sacrificing his life for the good of his genes².

　　一些生物学家认为雄蛛是为他的基因而牺牲的。

　　In other words, his becoming a meal for his paramour somehow helps the offspring of their union.

　　换句话说，他成为情人的腹中食某种程度上有助于他们共同的后代。

　　Peng Yu, of Hubei University in China, and his colleagues, decided³ to try to settle the question.

　　中国湖北大学的彭宇及其同事决定尝试解开这一谜题。

　　The results of their investigation⁴ are published this week in Behavioral Ecology and Sociobiology.

　　他们的条查结果刊登在《行为生态学与社会生物学》。

　　Dr Peng and his team collected almost 400 young wolf spiders, of both sexes, from local fields.

　　彭博士和他的小组在当地收集了几乎400只狼蛛，

　　They then raised the animals separately until they were sexually mature.

　　再雌雄分开饲养，直到它们性成熟。

　　Then, one at a time, they introduced the females to a male and watched until one of three things happened:

　　然后他们每次一只，将雌蛛与雄蛛配对，直到出现以下三者之一的情况发生：

　　the male got eaten; the male mated with the female and successfully avoided being eaten; or the male survived for half an hour, but did not mate with the female within that time.

　　雄蛛被吃；雄蛛与雌蛛交配后幸免于难；或者雄蛛存活了半小时，而期间未与雌蛛交配。有时，他们将未交配的雌雄蛛配对；

　　Sometimes the researchers paired virgin⁵ males with virgin females; sometimes they paired virgin males with females that had recently bred.

　　有时他们将未交配的雄蛛与刚繁殖过的雌蛛配对。

　　And in one crucial set of tests they paired virgin males with virgin females that had been taken off their regular diet of fruit flies a fortnight beforehand, and were thus presumed to be feeling more than a little peckish.

　　在一项关键性实验中，他们将未交配的雄蛛与停饲果蝇两周的雌蛛配对—此时假设雌蛛处于极度饥饿状态。

　　After doing all this, the team chose 16 females that had mated and then eaten their partners, and ten that had mated but not done so, and followed their reproductive success.

　　配对后，实验小组挑选了16只交配后吃掉配偶的雌蛛，10只交配后未吃掉配偶的雌蛛，观察其繁殖成功的过程。

　　When these females laid their egg sacs, the researchers picked ten sacs at random⁶ from each group and monitored those until the eggs hatched.

　　当这些雌蛛产下卵袋时，研究者从每组随机挑选了10个卵袋观察，直到卵孵化。

　　At that point they selected 20 spiderlings from each group for further study.

　　这时，他们从每组挑选10只幼蛛用于后续研究。

　　Their first pertinent⁷ observation was that, while female wolf spiders did indeed sometimes eat males before breeding with them, that happened only 10% of the time, and did not seem to be more frequent if the female had been starved.

　　他们第一个客观观察结果是，雌狼蛛有时确实会在交配前吃掉雄狼蛛，这种概率是10%，并且似乎不比雌蛛挨饿后比率高。

　　Their second observation was that if a male was deemed suitable to mate with, he was never eaten in copula—even though copulation could last as long as an hour and a half.

　　第二个观察结果是，如果雄蛛被认为适合交配，它们绝不会在交配中被吃—即使交配过程可能长达一个半小时。

　　Their third was that, 28% of the time, a male that had mated was indeed eaten afterwards.

　　他们第三个观察结果是，有28%的几率雄蛛会在交配后被吃。

　　Successful suitors, then, succumbed⁸ more often than unsuccessful ones.

　　如此可得出，交配成功的雄蛛被吃的比未成功的多。

　　The crucial finding, however—which makes sense of all the others—was the success of the spiderlings.

　　然而，幼蛛成活率是关键的发现—这使得其他发现都有了意义。

　　Young born of females that had eaten their partners had a 48% chance of making it through their first month of life.

　　吃掉配偶的雌蛛其后代48%可以活过一个月，

　　Those born of females who had let their partners live, had only a 12% chance of surviving that long.

　　而放生配偶的雌蛛的后代存活相同时间的只有12%。

　　That is a staggering difference—and certainly, in evolutionary⁹ terms, enough to drive self-sacrificial behaviour by males,

　　这个差距是巨大的—当然，按照进化论原则，足以使雄蛛采取自我牺牲行为。

　　since a male would have to mate successfully another three times to match the benefit he gains by this one suicidal act.

　　因此，为获得这一次自杀行为带来的好处，它之前必须成功交配三次。

　　The reason a male is almost three times as likely to be eaten if he has mated with the female in question than if he has not is thus probably that he wants to be eaten, for the good of his posterity¹⁰.

　　讨论中，如果与雌蛛交配成功，雄蛛被吃的概率几乎是未交配成功的雄蛛的三倍，其原因可能是为后代着想，它希望被吃。

　　Just what it is that a male meal gives, via the female's digestive system, to the hatchling spiders, remains¹¹ to be determined¹².

　　通过雌蛛的消化系统，雄蛛给予孵化蜘蛛的是什么？这还有待探索。

　　Perhaps spider bodies contain some crucial nutrients¹³ which are scarcer in other forms of prey¹⁴.

　　也许蜘蛛体内含有其他猎物所缺乏的重要的营养成分。

　　Whatever the details, though, the general answer to the biologists' question is now clear.

　　不管具体如何，生物学家们的问题有了大致的答案。

　　In the case of spiders, fathers really do lay down their lives for their children.

　　对蜘蛛来说，父亲们真真是为孩子放弃了他们的生命。

　　1.sacrifice for 为…而牺牲

　　Wmat did you ever sacrifice for mim?

　　你有为他牺牲过什么吗？

　　Why should a girl sacrifice for a man?

　　为什么一个女孩要为一个男人牺牲？

　　2.polish off 吃完；干完；击倒

　　No matter what he is offered to eat he polishes it off in an instant.

　　不管给他吃什么，他都能眨眼就下肚。

　　He polished off his scotch¹⁵ and slammed the glass down.

　　他一仰脖喝完苏格兰威士忌，砰的一声把杯子放下。

　　3.run away 逃跑，走掉；逃脱

　　I ran away from home when I was sixteen.

　　我16岁的时候离家出走了。

　　After his beating Colin ran away and hasn't been heard of since.

　　科林被他打了一顿后就离家出走了，从此杳无音讯。

　　4.decide to 决定

　　Why did you decide to talk about it?

　　那你为什么还决定把这件事说出来？

　　When you decide to improve your life, you really do.

　　当你决定去改变你的生活，你真的做了。

1 supreme   

adj.极度的，最重要的；至高的，最高的

参考例句：

• It was the supreme moment in his life.那是他一生中最重要的时刻。
• He handed up the indictment to the supreme court.他把起诉书送交最高法院。

2 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

3 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

4 investigation   

n.调查，调查研究

参考例句：

• In an investigation,a new fact became known, which told against him.在调查中新发现了一件对他不利的事实。
• He drew the conclusion by building on his own investigation.他根据自己的调查研究作出结论。

5 virgin   

n.处女，未婚女子；adj.未经使用的；未经开发的

参考例句：

• Have you ever been to a virgin forest?你去过原始森林吗？
• There are vast expanses of virgin land in the remote regions.在边远地区有大片大片未开垦的土地。

6 random   

adj.随机的；任意的；n.偶然的(或随便的)行动

参考例句：

• The list is arranged in a random order.名单排列不分先后。
• On random inspection the meat was found to be bad.经抽查，发现肉变质了。

7 pertinent   

adj.恰当的；贴切的；中肯的；有关的；相干的

参考例句：

• The expert made some pertinent comments on the scheme.那专家对规划提出了一些中肯的意见。
• These should guide him to pertinent questions for further study.这些将有助于他进一步研究有关问题。

8 succumbed   

不再抵抗（诱惑、疾病、攻击等）( succumb的过去式和过去分词 )； 屈从； 被压垮； 死

参考例句：

• The town succumbed after a short siege. 该城被围困不久即告失守。
• After an artillery bombardment lasting several days the town finally succumbed. 在持续炮轰数日后，该城终于屈服了。

9 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。

10 posterity   

n.后裔，子孙，后代

参考例句：

• Few of his works will go down to posterity.他的作品没有几件会流传到后世。
• The names of those who died are recorded for posterity on a tablet at the back of the church.死者姓名都刻在教堂后面的一块石匾上以便后人铭记。

11 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

12 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。

13 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》

14 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。

15 scotch   

n.伤口，刻痕；苏格兰威士忌酒；v.粉碎，消灭，阻止；adj.苏格兰(人)的

参考例句：

• Facts will eventually scotch these rumours.这种谣言在事实面前将不攻自破。
• Italy was full of fine views and virtually empty of Scotch whiskey.意大利多的是美景，真正缺的是苏格兰威士忌。