科学美国人60秒 犬类拥有复杂的遗传进化史

This is Scientific American's 60-second Science, I'm Eliene Augenbraun.

这里是科学美国人——60秒科学系列，我是埃琳·奥根布朗。

Dogs were the first animals to be domesticated¹.

狗是最早被驯养的动物。

And they stuck with us as we changed lifestyles from hunting/gathering to farming to city living.

当我们的生活方式从狩猎/采集到农耕再到城市生活时，它们一直跟着我们。

“The dog is a species that is intimately linked to human history.”

“狗是一个与人类历史密切相关的物种。”

Anders Bergstrom, a postdoc at the Francis Crick Institute in London.

安德斯·伯格斯特罗姆是伦敦弗朗西斯·克里克研究所的博士后。

He and his colleagues studied the genomes of 27 ancient dog bones dug up around the world.

他和他的同事研究了在世界各地挖掘的27块古代狗骨头的基因组。

They found that by 11,000 years ago ...

他们发现，在11000年前……

“We see that the dog started to diversify² genetically⁴.

“我们发现狗开始在基因上多样化。

So we find evidence of at least five major lineages of dogs already at this time.”

我们在这一时期已经发现了至少5种主要犬类谱系的证据。”

Dog remains⁵ have been found in Europe, Asia and the Americas in a pattern similar to how humans moved and mixed.

在欧洲、亚洲和美洲发现了狗的遗骸，其模式与人类的迁徙和融合方式相似。

“To a large degree, the history of dogs seems to have been shaped by human history—so likely reflecting how, when humans moved, they would have brought their dogs with them.”

“在很大程度上，狗的历史似乎受到了人类历史的影响——这很可能反映了人类在移动时是如何带着他们的狗的。”

Ancient humans clearly found dogs to be very useful.

古人类显然发现狗非常有用。

“In the Arctic, there’s evidence that sled dogs actually emerged very early, and people used them for the particular purpose of sledding, perhaps as early as 10,000 years ago.”

“在北极，有证据表明，雪橇狗实际上很早就出现了，人们可能早在1万年前就将它们用于滑雪橇的特殊目的。”

A few modern breeds—like the African basenji, New Guinea singing dog or Australian dingo—are similar to one of the five ancient lineages.

一些现代品种——如非洲巴仙吉犬、新几内亚歌唱犬或澳大利亚野犬——与五种犬类谱系之一相似。

Most other modern breeds derive⁶ at least in part from European dogs, which came to dominate dog genomes.

大多数现代犬类品种至少部分源自欧洲犬类，欧洲犬类在犬类基因组中占主导地位。

“If you go back 4,000 or 5,000 years ago, there’s a great diversity of dogs in Europe.

“如果你回到4000或5000年前，欧洲的犬类纷杂，具有多样性。

But at some point, there was probably a single population that expanded and basically replaced other populations in Europe.

但在某个时刻，可能只有一个种群在扩张，基本上取代了欧洲的其他种群。

This was something that we did not predict and you couldn’t really see just from studying archaeology⁷.

这是我们没有预料到的，仅仅通过研究考古学是无法看到的。

But when we look at the DNA⁸, we see that there’s all this diversity in the past that is not represented in present-day dogs.”

但当我们观察DNA时，我们发现过去的所有这些多样性都没有在今天的狗身上体现出来。”

The study is in the journal Science, where you’ll find maps of dog migrations⁹ over time.

这项研究发表在《科学》杂志上，你可以在杂志上找到狗的迁徙地图。

One odd finding: about 11,000 years ago, it looks like dogs spread more widely than humans did.

一个奇怪的发现是:大约11000年前，狗的分布似乎比人类更广泛。

“That’s actually a process we don’t really understand.

“这实际上是一个我们并不真正了解的过程。

So how could the dog spread so quickly and widely?

那么，狗是如何传播得如此迅速和广泛的呢?

We’re not aware of any human migrations at this time that could have facilitated the spread of the dog.

目前我们还没有发现这个时期的任何人类迁徙可能会促进狗的扩张。

But somehow it spreads very quickly to human groups all across the world, perhaps because it was a very useful thing for these early human hunter-gatherer groups.”

但狗以某种方式迅速扩张到世界各地的人类群落，可能是因为它对这些早期人类狩猎-采集群落非常有用。”

Humans were also useful to dogs.

人类对狗也很有用。

Prehistoric¹⁰ Petcos didn’t exist, so dogs probably ate what humans did.

史前的宠物狗并不存在，所以狗可能吃的和人类一样。

And as humans started to farm, both species quickly adapted to digest more grains.

随着人类开始农耕，这两个物种很快就适应了消化更多的谷物。

The number of copies of a starch-digesting gene³ in both humans and dogs increased in the generations following the invention of agriculture.

在农业发明后的几代中，人类和狗的淀粉消化基因拷贝数都在增加。

“Yeah, so that’s a very striking example of convergent¹¹ evolution between humans and dogs.

“是的，这是人类和狗之间趋同进化的一个非常显著的例子。

In a way, it’s kind of interesting to think of the dog as a kind of an evolutionary¹² experiment that runs alongside human history and undergoes the same lifestyle changes that we do.”

在某种程度上，把狗看作是一种进化实验，它与人类历史相伴，经历着与我们一样的生活方式改变，这是一种有趣的想法。”

For Scientific American's 60-second Science. I'm Eliene Augenbraun.

感谢收听科学美国人——60秒科学。我是埃琳·奥根布朗。

1 domesticated   

adj.喜欢家庭生活的；（指动物）被驯养了的v.驯化( domesticate的过去式和过去分词 )

参考例句：

• He is thoroughly domesticated and cooks a delicious chicken casserole. 他精于家务，烹制的砂锅炖小鸡非常可口。 来自《简明英汉词典》
• The donkey is a domesticated form of the African wild ass. 驴是非洲野驴的一种已驯化的品种。 来自《简明英汉词典》

2 diversify   

v.（使）不同，（使）变得多样化

参考例句：

• Our company is trying to diversify.我们公司正力图往多样化方面发展。
• Hills and woods diversify the landscape.山陵和树木点缀景色。

3 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。

4 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

5 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。

6 derive   

v.取得；导出；引申；来自；源自；出自

参考例句：

• We derive our sustenance from the land.我们从土地获取食物。
• We shall derive much benefit from reading good novels.我们将从优秀小说中获得很大好处。

7 archaeology   

n.考古学

参考例句：

• She teaches archaeology at the university.她在大学里教考古学。
• He displayed interest in archaeology.他对考古学有兴趣。

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 migrations   

n.迁移，移居( migration的名词复数 )

参考例句：

• It foundered during the turmoils accompanying the Great Migrations. 它在随着民族大迁徙而出现的混乱中崩溃。 来自辞典例句
• Birds also have built-in timepieces which send them off on fall and spring migrations. 鸟类也有天生的时间感应器指导它们秋春迁移。 来自互联网

10 prehistoric   

adj.（有记载的）历史以前的，史前的，古老的

参考例句：

• They have found prehistoric remains.他们发现了史前遗迹。
• It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。

11 convergent   

adj.会聚的

参考例句：

• A curved-inwards wall has a convergent effect on wall spray.凹型壁面对碰壁喷雾有聚集作用。
• If a sequence is not convergent,it is divergent.如果一个序列不收敛，我们称它发散。

12 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。