VOA慢速英语2012 SCIENCE IN THE NEWS - The Search for DNA from A Creature That May Not Exist

 

SCIENCE IN THE NEWS - The Search for DNA¹ from A Creature That May Not Exist

BOB DOUGHTY²: This is SCIENCE IN THE NEWS, in VOA Special English. I’m Bob Doughty.

BARBARA KLEIN: And I’m Barbara Klein. Today we tell about an appeal for genetic³ material from a famous creature that may not even exist. We report on the health of a man who lived five thousand years ago. And we tell about the effect of changing weather conditions on human ancestors -- the Neanderthals.

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BOB DOUGHTY: Scientists have launched a genetic search for a large, ape-like creature called the Yeti. They are appealing to people who claim that Yetis exist to provide evidence of the creature.

Researchers from Oxford⁴ University and the Swiss Lausanne Museum of Zoology⁵ are calling their study the Collateral⁶ Hominid Project. Hominid is the general genetic family of primates⁷. It includes modern human beings, also known as homo sapiens. The family also includes all other early human and human-like species.

BARBARA KLEIN: The Yeti is said to live in the mountains of Nepal and Tibet. It is most often described as a large, hairy hominid. It reportedly stands between two and two and one-half meters tall. The name Yeti means “magical creature” in the Tibetan language. Some people have called the creature, The Abominable⁸ Snowman or Sasquatch.

Creatures like the Yeti are known as cryptids. A cryptid is an animal that some people say exists, although there is no strong evidence that it does. There can be what is called “circumstantial evidence,” like unconfirmed sightings that cryptids exist. Yet scientific proof is lacking.

Other cryptids are Scotland’s Loch Ness Monster, Big Foot in North America, and central Africa’s dinosaur-like Mokele Mbembe.

BOB DOUGHTY: Researchers from the Collateral Hominid Project have appealed to individuals and organizations who say Yetis exist. They want to examine organic remains⁹ said to belong to the creature. The scientists say they are especially interested in testing pieces of hair. They plan to use recently-developed methods for studying DNA -- deoxyribonucleic acid. They say these methods produce clear results that cannot be falsified. They are planning to write a report about their findings and send it to a scientific journal for all the world to read.

In case you were wondering, the researchers say they do not expect to find any evidence proving Yetis exist. But they are promising¹⁰ to examine what is sent to them. They are accepting organic material for testing until September. The DNA tests are set to last from September through November.

(MUSIC)

BOB DOUGHTY: About twenty years ago, the mummified remains of a man were discovered in a melting glacier¹¹ in the Italian Alps. The remains were said to be in very good condition. Tests showed that they were about five thousand three hundred years old. The mummy came to be called the Iceman. Scientists called him Oetzi because of where he was found. His body was frozen and mummified in the place where he fell after he was killed.

Over the years, Oetzi came to be buried under layers of ice and snow. But as the Earth’s climate warmed, those layers began to melt. In nineteen ninety-one, two Germans found the body while exploring the Oetztal Alps, near the border between Italy and Austria.

BARBARA KLEIN: Recently, European scientists announced completion of a DNA map of Oetzi. They said the map provided details about his appearance, his ethnic¹² origins and even his health.

The details are described in a paper by scientists at the European Academy for Mummies and the Iceman in Italy, and at the Institute for Human Genetics in Germany. Among the findings is that Oetzi was genetically¹³ at risk for heart disease. Yet the scientists say he was not overweight and probably was very active. They say this information is important because it shows that heart disease existed more than five thousand years ago. They say that means the problem cannot be blamed on modern lifestyles or customs.

BOB DOUGHTY: Oetzi’s newly-mapped genome also shows that he suffered from borreliosis, also known as Lyme disease. The scientists say this is the earliest-known case of the disease. They say it proves that the disorder¹⁴ was present in the New Stone Age period.

The scientists found that Oetzi was unable to digest milk products. They say he became sick after eating such products or drinking milk. They say this finding supports the belief that what is called “lactose intolerance” was still a common condition in Oetzi’s time. Yet his people were becoming increasingly involved in farming. And some people raised dairy animals for their milk. Today, most Asians and Africans suffer from lactose intolerance, but few northern Europeans do.

BARBARA KLEIN: The researchers believe Oetzi’s ancestors probably came from the Middle East. The ancestors were thought to have moved to Europe, as agriculture continued to spread. The researchers say few modern-day Europeans share genes¹⁵ with the Iceman. Those who do live mostly in areas separate from the European mainland, like the Mediterranean¹⁶ islands of Sardinia and Corsica.

Oetzi’s DNA map also has helped researchers recreate his physical appearance. They say he weighed about fifty kilograms, and had brown eyes and long brown hair. He was about one point six meters tall. This was an average height for a man during the New Stone Age.

BOB DOUGHTY: A report on the Iceman’s complete genome is published in the journal Nature Communications. 

Earlier studies found that Oetzi died at the age of forty-five. Examinations of wounds on his back show he was murdered. He was shot in the back with an arrow and left to suffer a cold and lonely death in the Alps.

Many scientists have noted¹⁷ the high quality of the clothing Oetzi was wearing and the fine copper¹⁸ axe¹⁹ in his possession. They say this likely means he and his family were probably important within their community.

(MUSIC)

BARBARA KLEIN: Finally, another study has found that most Neanderthals had largely disappeared across most of Europe fifty thousand years ago. That is long before our ancestors, homo sapiens, first arrived on the continent.

A team of researchers says its findings dispute the long-held belief that Neanderthals were in Europe for hundreds of thousands of years until modern Homo sapiens arrived. The researchers based their findings from studies of DNA taken from fossilized remains of thirteen Neanderthals who lived in what is now northern Spain.

BOB DOUGHTY: The scientists say the Neanderthal human species had died off as early as fifty thousand years ago. But they say a small group survived for another ten thousand years in areas of central and western Europe. The results suggest that Neanderthals may have been more affected²⁰ by the sudden changes in climate during the last Ice Age than had been believed.

The DNA tests showed that older European Neanderthals had a much-greater mix of genes than much later Neanderthal populations. Older Asian Neanderthals also had a much greater genetic variation than the later populations.

BARBARA KLEIN: The researchers say they contacted other experts to help confirm their findings. That is because all of their results are based on severely-degraded, or damaged, DNA. They used both modern laboratory and computational methods to reach their findings.

The scientists say they only felt sure of their findings after an international research team studied them. They believe the genetic information reveals an important and formerly²¹ unknown part of Neanderthal history.

Scientists from the University of Uppsala in Sweden led the study. They worked with researchers from Spain, Denmark and the United States. A report on the team’s findings is published in the journal Molecular²² Biology and Evolution.

(MUSIC)

BOB DOUGHTY: This SCIENCE IN THE NEWS was adapted into Special English by Christopher Cruise. Our producer was June Simms. I’m Bob Doughty.

BARBARA KLEIN: And I’m Barbara Klein. 

Join us again next week for more news about science in Special English on the Voice of America.

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 doughty   

adj.勇猛的，坚强的

参考例句：

• Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质：脾气倔强，性格刚强。
• The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。

3 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。

4 Oxford   

n.牛津（英国城市）

参考例句：

• At present he has become a Professor of Chemistry at Oxford.他现在已是牛津大学的化学教授了。
• This is where the road to Oxford joins the road to London.这是去牛津的路与去伦敦的路的汇合处。

5 zoology   

n.动物学，生态

参考例句：

• I would like to brush up my zoology.我想重新温习一下动物学。
• The library didn't stock zoology textbooks.这家图书馆没有动物学教科书。

6 collateral   

adj.平行的；旁系的；n.担保品

参考例句：

• Many people use personal assets as collateral for small business loans.很多人把个人财产用作小额商业贷款的抵押品。
• Most people here cannot borrow from banks because they lack collateral.由于拿不出东西作为抵押，这里大部分人无法从银行贷款。

7 primates   

primate的复数

参考例句：

• Primates are alert, inquisitive animals. 灵长目动物是机灵、好奇的动物。
• Consciousness or cerebration has been said to have emerged in the evolution of higher primates. 据说意识或思考在较高级灵长类的进化中已出现。

8 abominable   

adj.可厌的，令人憎恶的

参考例句：

• Their cruel treatment of prisoners was abominable.他们虐待犯人的做法令人厌恶。
• The sanitary conditions in this restaurant are abominable.这家饭馆的卫生状况糟透了。

9 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。

10 promising   

adj.有希望的，有前途的

参考例句：

• The results of the experiments are very promising.实验的结果充满了希望。
• We're trying to bring along one or two promising young swimmers.我们正设法培养出一两名有前途的年轻游泳选手。

11 glacier   

n.冰川，冰河

参考例句：

• The glacier calved a large iceberg.冰河崩解而形成一个大冰山。
• The upper surface of glacier is riven by crevasses.冰川的上表面已裂成冰隙。

12 ethnic   

adj.人种的，种族的，异教徒的

参考例句：

• This music would sound more ethnic if you played it in steel drums.如果你用钢鼓演奏，这首乐曲将更具民族特色。
• The plan is likely only to aggravate ethnic frictions.这一方案很有可能只会加剧种族冲突。

13 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

14 disorder   

n.紊乱，混乱；骚动，骚乱；疾病，失调

参考例句：

• When returning back,he discovered the room to be in disorder.回家后，他发现屋子里乱七八糟。
• It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。

15 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

16 Mediterranean   

adj.地中海的；地中海沿岸的

参考例句：

• The houses are Mediterranean in character.这些房子都属地中海风格。
• Gibraltar is the key to the Mediterranean.直布罗陀是地中海的要冲。

17 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

18 copper   

n.铜；铜币；铜器；adj.铜(制)的；(紫)铜色的

参考例句：

• The students are asked to prove the purity of copper.要求学生们检验铜的纯度。
• Copper is a good medium for the conduction of heat and electricity.铜是热和电的良导体。

19 axe   

n.斧子；v.用斧头砍，削减

参考例句：

• Be careful with that sharp axe.那把斧子很锋利，你要当心。
• The edge of this axe has turned.这把斧子卷了刃了。

20 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

21 formerly   

adv.从前，以前

参考例句：

• We now enjoy these comforts of which formerly we had only heard.我们现在享受到了过去只是听说过的那些舒适条件。
• This boat was formerly used on the rivers of China.这船从前航行在中国内河里。

22 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。