2022年经济学人 2022年诺奖获得者破译尼安德特人基因组(2)

Mitochondrial DNA¹ is passed intact from mother to offspring.

线粒体DNA会原封不动地由母亲遗传给后代。

It is not involved in sexual mixing, so it changes only by the random² process of mutation³.

它不参与有性生殖中的基因重组，所以只有在随机突变中才会发生变化。

The lack of mutations that might have distinguished⁴ the DNA of the individuals in question from each other suggests not only a common ancestor, but a relatively⁵ recent one.

文中提到的两个个体的DNA不存在能够将彼此区分开来的突变，这不仅表明他们有共同的祖先，而且说明这个共同祖先存在的时间并不十分久远。

Further analysis showed also that two of the mitochondrial DNA samples from Chagyrskaya were closer to the Okladnikov boy than to any of the other Chagyrskayans.

通过进一步的分析，Chagyrskaya洞穴两个个体的线粒体DNA样本表明，这两个个体与Okladnikov洞穴男孩的亲缘关系，比他们和同洞穴其他个体的关系都要近。

And when the team looked at data on y-chromosomes, which pass intact from father to son, as well as their mitochondrial data, they were able to draw some tentative conclusions about Neanderthal communities.

研究小组研究了由父亲传给儿子的y染色体的数据，以及样本中线粒体的数据，得出了一些关于尼安德特人群体的初步结论。

If members of a population mate more or less at random with those of the opposite sex, the so-called coalescence⁶ time - how far in the past their most recent common ancestor lived - should be the same for mitochondrial (matrilineal) and y-chromosome (patrilineal) DNA.

如果一个种群的成员在某种程度上随机与异性进行交配，那么线粒体(在母系中传递)DNA和y染色体(在父系中传递)DNA的所谓“溯祖时间”，即种群成员最后一个共同祖先出现距今的这段时间，应该是相同的。

The researchers found, however, that the average coalescence time for the y-chromosome was 500 years, while that for the mitochondrial genome was around 5,000 years.

然而，研究人员发现，y染色体的平均溯祖时间为500年，而线粒体基因组的平均溯祖时间约为5000年。

To explain this order-of-magnitude difference, they modelled various possibilities.

为了解释这种数量级的差异，研究人员对各种可能性进行了模拟。

The one which best fitted the data was that the Neanderthals of the Altai lived in groups of around 20 individuals, with at least 60% of the females in a group having migrated there from elsewhere.

最符合数据结果的情况是，居住在阿尔泰山的尼安德特人组成了很多大约20个人的群体，其中至少有60%的女性是从其他地方迁徙到那里的。

The size of such groups is similar to that deduced for Palaeolithic bands of Homo sapiens, which probably had around 25 members.

群体的大小与推断得到的旧石器时代大约由25人组成的智人群体类似。

When dealing⁷ with humanity's ancestors and cousins it is easy and tempting⁸ to over-interpret the scarce data available - and practitioners⁹ of the subject have indeed been guilty of doing this in the past.

在研究人类的祖先和近亲的课题时，人们很容易过度解读现有的稀有数据——而这一课题的研究者过去确实犯过这样的错误。

So these conclusions should be treated with care.

因此，我们应该更加谨慎地对待这些结论。

But if nothing else, this study shows that the methods which brought Dr. Paabo his prize have increased the pool of data available for such speculations¹⁰ in an extraordinary way.

但至少，这项研究表明，让佩博博士获得诺贝尔奖的研究方法，以一种非同寻常的方式扩充了可用于此类研究推测的数据库。

1 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。

2 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。

3 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。

4 distinguished   

adj.卓越的，杰出的，著名的

参考例句：

• Elephants are distinguished from other animals by their long noses.大象以其长长的鼻子显示出与其他动物的不同。
• A banquet was given in honor of the distinguished guests.宴会是为了向贵宾们致敬而举行的。

5 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

6 coalescence   

n.合并，联合

参考例句：

• It is formed by the coalescence of the first three neuromeres in the embryo .它是由胚胎时的前三个神经原节愈合而成的。
• The other process of droplet growth is by collision and coalescence.云滴增长的另一个过程是各云滴间的碰撞和并合。

7 dealing   

n.经商方法，待人态度

参考例句：

• This store has an excellent reputation for fair dealing.该商店因买卖公道而享有极高的声誉。
• His fair dealing earned our confidence.他的诚实的行为获得我们的信任。

8 tempting   

a.诱人的, 吸引人的

参考例句：

• It is tempting to idealize the past. 人都爱把过去的日子说得那么美好。
• It was a tempting offer. 这是个诱人的提议。

9 practitioners   

n.习艺者，实习者( practitioner的名词复数 )；从业者（尤指医师）

参考例句：

• one of the greatest practitioners of science fiction 最了不起的科幻小说家之一
• The technique is experimental, but the list of its practitioners is growing. 这种技术是试验性的，但是采用它的人正在增加。 来自辞典例句

10 speculations   

n.投机买卖( speculation的名词复数 )；思考；投机活动；推断

参考例句：

• Your speculations were all quite close to the truth. 你的揣测都很接近于事实。 来自《现代英汉综合大词典》
• This possibility gives rise to interesting speculations. 这种可能性引起了有趣的推测。 来自《用法词典》