【英语语言学习】狗狗的进化史

Robyn Williams: And this is The Science Show on RN where we’ve long tracked the evolution of dogs. Now clearly going far further back than we thought, so we can imagine now a bunch of feral people, all very rough—roaming around the woods, coming across a group of bright, civilised canines¹. And being adopted by them. The dogs domesticated³ us. Any chance? Olivia Willis reports.

Olivia Willis: It’s the evolution debate that’s divided the scientific community for decades: dogs, where they come from and how they came to be, has largely remained a mystery. But researchers in Sweden may have finally cracked the code. With the report released last month showing that human domestication⁴ of dogs is twice as old as previously⁵ thought. The paper, published in Current Biology, has found that dogs split from wolves at least 27,000 years ago, and possibly up to 40,000 years ago. 40,000, it’s astonishing really, when you consider that the conventional domestication of most animals—say goats or cattle—happened just 10 to 12,000 years ago.

The new findings were based on a bone fragment found in Siberia, and revealed a new species of wolf that was a side branch of the common ancestor of modern wolves and dogs. Scientists compared the differences between the genome of the ancient wolf and those of modern wolves and dogs, and built a family tree showing the two had split much earlier than previously thought. However the study, while impressive, wasn’t able to conclude much about the domestication process itself. Understanding where, when, and exactly how humans developed a close companionship with what are otherwise wild and fierce creatures, remains⁶ a hotly contested bone of contention⁷. Early signs of domestication emerged in the late 1970s when scientists in northern Israel discovered a puppy buried in the arms of a human under a 12,000-year-old home, suggesting that dogs were domesticated in the Middle East, shortly before people took up farming.

But it wasn’t long before other evidence suggested domestication took place in Asia, or even Europe. It was Peter Savolainen, a Swedish professor of evolutionary⁸ genetics, who created the world’s first canine² DNA¹⁰ database. He conducted a study that examined DNA sequence variation among 654 domestic dogs. Through his research, Savolainen began to recognise a pattern that eastern Asian dogs were more genetically¹¹ diverse, a trademark¹² of ancient origins. Further study in 2009 led Savolainen to conclude that dogs had originated from a region south of China’s Yangtze River, less than 16,500 years ago, when humans were transitioning from hunters and gatherers, to farming and agriculture. Although his team couldn’t decipher just how or why they’d been domesticated, Savolainen was confident that he’d solved the basic canine question. But not everybody was convinced. Robert Wayne, and evolutionary biologist at the University of California, believes that Savolainen’s approach of using only modern DNA is a gross oversight¹³.

Wayne says that any genetic⁹ diversity in modern Asian dogs—the crux¹⁴ of Savolainen’s theory—is not necessarily an indication of ancient origins, but rather a result of human colonisation, as dogs regularly interbred with wolves and canines from other regions. Wayne instead focused his attention on ancient DNA, and in 2013 his team published the most extensive analysis of ancient dog and wolf genomes to date, and concluded that dogs had evolved from an ancient group of wolves in Europe. Somewhere between 19 and 32,000 years ago. So the mystery of dog domestication remained, that’s when scientists Greger Larson and Keith Dobney stepped in and things got even more interesting. Larson and Dobney had grown frustrated¹⁵ over the continued disputes about canine origins because no studies—especially those of Savolainen and Wayne—were combining both ancient and modern DNA and using a broad range of geographic¹⁶ samples.

So Larson and Dobney set to work, attempting to analyse as many samples as possible, from as many places as possible. Combining ancient DNA analysis, with modern techniques. So far they’ve analysed more than 3,000 specimens¹⁷, and their first and highly anticipated paper is due to be published in coming months. They hope to finally determine when and where wolves transitioned from wild animals of the forest to man’s beloved, best friend.

Robyn Williams: More than 40,000 years ago, I’ll bet you. Olivia Willis on the story reported in The New Scientist this week on page 12, and is the cover story of the journal Science, on 17th of April. And so for the rest of The Science Show, big data: computers, and later, dating. For first we go way back.

1 canines   

n.犬齿( canine的名词复数 )；犬牙；犬科动物

参考例句：

• For example, the teeth are more primitive. There are large canines and unusually shaped incisors. 譬如，牙齿更为原始，有大的犬齿和非常合适的门齿。 来自辞典例句
• Well-to-canines can attend doggy daycare centers while their owners work. 富人家的狗在主人上班的时候可以去狗狗托管中心。 来自互联网

2 canine   

adj.犬的，犬科的

参考例句：

• The fox is a canine animal.狐狸是犬科动物。
• Herbivorous animals have very small canine teeth,or none.食草动物的犬牙很小或者没有。

3 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》

4 domestication   

n.驯养，驯化

参考例句：

• The first was the domestication of animals. 第一个阶段是驯养动物。 来自《简明英汉词典》
• In northwestern China, there is no evidence for endemic domestication of any animals. 在中国西北，没有任何当地动物驯化的迹象。 来自辞典例句

5 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

6 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。

7 contention   

n.争论，争辩，论战；论点，主张

参考例句：

• The pay increase is the key point of contention. 加薪是争论的焦点。
• The real bone of contention,as you know,is money.你知道，争论的真正焦点是钱的问题。

8 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。

9 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。

10 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。

11 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

12 trademark   

n.商标；特征；vt.注册的…商标

参考例句：

• The trademark is registered on the book of the Patent Office.该商标已在专利局登记注册。
• The trademark of the pen was changed.这钢笔的商标改了。

13 oversight   

n.勘漏，失察，疏忽

参考例句：

• I consider this a gross oversight on your part.我把这件事看作是你的一大疏忽。
• Your essay was not marked through an oversight on my part.由于我的疏忽你的文章没有打分。

14 crux   

adj.十字形；难事，关键，最重要点

参考例句：

• The crux of the matter is how to comprehensively treat this trend.问题的关键是如何全面地看待这种趋势。
• The crux of the matter is that attitudes have changed.问题的要害是人们的态度转变了。

15 frustrated   

adj.挫败的，失意的，泄气的v.使不成功( frustrate的过去式和过去分词 )；挫败；使受挫折；令人沮丧

参考例句：

• It's very easy to get frustrated in this job. 这个工作很容易令人懊恼。
• The bad weather frustrated all our hopes of going out. 恶劣的天气破坏了我们出行的愿望。 来自《简明英汉词典》

16 geographic   

adj.地理学的，地理的

参考例句：

• The city's success owes much to its geographic position. 这座城市的成功很大程度上归功于它的地理位置。 来自《简明英汉词典》
• Environmental problems pay no heed to these geographic lines. 环境问题并不理会这些地理界限。 来自英汉非文学 - 环境法 - 环境法

17 specimens   

n.样品( specimen的名词复数 )；范例；（化验的）抽样；某种类型的人

参考例句：

• Astronauts have brought back specimens of rock from the moon. 宇航员从月球带回了岩石标本。
• The traveler brought back some specimens of the rocks from the mountains. 那位旅行者从山上带回了一些岩石标本。 来自《简明英汉词典》