万物简史 第597期:生命的物质(23)

Altogether, almost half of human genes² — the largest proportion yet found in any organism — don't do anything at all, as far as we can tell, except reproduce themselves.

据我们所知，总共有近一半的人类基因——任何生物体内基因已知的最大比例——除了复制它们自己，它们根本不做任何事情。

All organisms are in some sense slaves to their genes. That's why salmon³ and spiders and other types of creatures more or less beyond counting are prepared to die in the process of mating. The desire to breed, to disperse⁴ one's genes, is the most powerful impulse in nature. As Sherwin B. Nuland has put it: "Empires fall, ids explode, great symphonies are written, and behind all of it is a single instinct that demands satisfaction." From an evolutionary⁵ point of view, sex is really just a reward mechanism⁶ to encourage us to pass on our genetic⁷ material.

从某种意义上讲，所有的生物都是其基因的奴隶。这就解释了为什么鲑鱼、蜘蛛以及其他数不清的生物在交配的同时也走向了死亡。繁殖后代、传递基因的欲望是自然界最强有力的冲动。正如谢尔文·B·纽兰所说：“帝国分崩离析，本我破壳而出，雄伟的交响乐笔下生成，这一切的背后是一种要求得到满足的本能。”从进化论的观点看，性本质上就是鼓励我们将基因传承给后代的一种机能。

Scientists had only barely absorbed the surprising news that most of our DNA⁸ doesn't do anything when even more unexpected findings began to turn up. First in Germany and then in Switzerland researchers performed some rather bizarre experiments that produced curiously⁹ unbizarre outcomes. In one they took the gene¹ that controlled the development of a mouse's eye and inserted it into the larva of a fruit fly. The thought was that it might produce something interestingly grotesque¹⁰. In fact, the mouse-eye gene not only made a viable¹¹ eye in the fruit fly, it made a fly's eye. Here were two creatures that hadn't shared a common ancestor for 500 million years, yet could swap¹² genetic material as if they were sisters.

科学家们好不容易接受了这样一个令人惊讶的事实，即我们DNA的绝大多数不做任何事情。紧接着，更意想不到的研究成果开始问世了。先是在德国，接着在瑞士，研究人员做了一系列奇怪的实验，其结果让人瞠目结舌。他们将控制老鼠眼睛发育的基因植入到果蝇的幼虫中。他们本来以为会产生某种有趣而怪异的东西，结果老鼠眼睛的基因不仅使得果蝇长出了一只老鼠的眼睛，同时也长出了一只果蝇的眼睛。这两类动物在长达5亿年的时间里分别拥有不同的祖先，但是它们却可以像姐妹一样交换基因。

1 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

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 salmon   

n.鲑，大马哈鱼，橙红色的

参考例句：

• We saw a salmon jumping in the waterfall there.我们看见一条大马哈鱼在那边瀑布中跳跃。
• Do you have any fresh salmon in at the moment?现在有新鲜大马哈鱼卖吗？

4 disperse   

vi.使分散；使消失；vt.分散；驱散

参考例句：

• The cattle were swinging their tails to disperse the flies.那些牛甩动着尾巴驱赶苍蝇。
• The children disperse for the holidays.孩子们放假了。

5 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。

6 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

7 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

8 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

9 curiously   

adv.有求知欲地；好问地；奇特地

参考例句：

• He looked curiously at the people.他好奇地看着那些人。
• He took long stealthy strides. His hands were curiously cold.他迈着悄没声息的大步。他的双手出奇地冷。

10 grotesque   

adj.怪诞的，丑陋的；n.怪诞的图案，怪人（物）

参考例句：

• His face has a grotesque appearance.他的面部表情十分怪。
• Her account of the incident was a grotesque distortion of the truth.她对这件事的陈述是荒诞地歪曲了事实。

11 viable   

adj.可行的，切实可行的，能活下去的

参考例句：

• The scheme is economically viable.这个计划从经济效益来看是可行的。
• The economy of the country is not viable.这个国家经济是难以维持的。

12 swap   

n.交换；vt.交换，用...作交易

参考例句：

• I will swap you my bicycle for your radio.我想拿我的自行车换你的收音机。
• This comic was a swap that I got from Nick.这本漫画书是我从尼克那里换来的。