VOA慢速英语2009年-SCIENCE IN THE NEWS - 'On the Origin o

VOICE ONE:

This is SCIENCE IN THE NEWS in VOA Special English. I'm Bob Doughty¹.

VOICE TWO:

And I'm Doug Johnson. November twenty-fourth marked the one hundred fiftieth anniversary of one of the most influential² books ever written. Naturalist³ Charles Darwin published "On the Origin of Species" in eighteen fifty-nine. The book was an immediate⁴ success in the scientific community. Today, evolution forms the basis for the modern science of biology.

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VOICE ONE:

Charles Darwin

Evolution can be defined as change in groups of living things over time. Small changes take place in each generation of organisms. Those with useful changes survive to reproduce. Changes that do not aid survival disappear. This is the idea of natural selection. Over long periods of time, these small changes result in the creation of new species. They are the reason for the many different kinds of life on Earth.

The idea that species change was not new even in Darwin's time. The idea dates back to ancient Greece. In the late eighteenth century, Darwin's grandfather, Erasmus Darwin, suggested that species evolved from their ancestors. He even thought that competition helped drive change.

At the beginning of the nineteenth century, Jean-Baptiste Lamark attempted a fuller explanation. He suggested that individual organisms changed in reaction to their environment and passed on these traits to the next generation.

VOICE TWO:

Darwin had been working on his theory for over twenty years when he published "On the Origin of Species." Yet it was the work of naturalist Alfred Russel Wallace that pushed Darwin to finally release his theory. Wallace had studied plants and animals in South America and the South Pacific. In eighteen fifty-eight, he sent Darwin a short study he had written containing ideas about evolution. Darwin was shocked by its similarity to his own work.

In July of that year, Darwin's friends Charles Lyell and Joseph Hooker had studies by both men presented to the scientific group called the Linnean Society of London. But the first explanation of evolution in public caused little reaction.

A year later, Darwin would complete his detailed⁶ study of evolution through natural selection. With its publication, Darwin gained important supporters like Thomas Huxley who were willing to defend his ideas.

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VOICE ONE:

Evolution, however, did not explain everything about how species evolved. It is important to remember that many of the greatest biological discoveries had yet to be made when Darwin published "On the Origin of Species."

WARREN SCHMAUS: "When Darwin first proposed his theory in eighteen fifty-nine, he had no concept of a gene⁵, no concept of a chromosome⁷, no concept of mutation⁸, and certainly no concept of things like DNA⁹ and RNA."

Professor Warren Schmaus of the Illinois Institute of Technology says the union of evolution and genetics only started around the nineteen thirties. Also, in Darwin's time, the age of the Earth was estimated only in the millions of years—too short a time some said for evolution to work. Not until the nineteen fifties did scientists, using radioactive dating, place the age of the Earth at over four billion years.

But natural selection has stood the test of time as a basis for the science of biology. Professor Schmaus notes that, before Darwin, naturalists¹¹ only collected and named species.

WARREN SCHMAUS: "I mean it's hard to even understand how biology was a science as we would recognize it today. I mean, where are the scientific explanations before Darwin?"

VOICE TWO:

To celebrate Darwin and his idea, the Smithsonian Institution's National Museum of Natural History in Washington created a special exhibit. "Since Darwin: The Evolution of Evolution" opened in September. It uses objects from the museum's collection to show how Darwin helped us understand the history of life on Earth. The goal is to show that evolution is not an old, accepted idea, but continues to be the basis for new discoveries, itself changing with modern science.

People from all over the world have visited the exhibit. Many people found the objects and displays helped explain a subject that is hard to understand.

VOICE ONE:

Jim and Irene Mikkelson were visiting Washington from Charlotte, North Carolina when they stopped by the museum. Mister Mikkelson called the exhibit educational.

JIM MIKKELSON: "I never really realized that that meant that every living thing really came as an evolutionary¹² development of the first seeds of life."

VOICE TWO:

Aravinda Pillalamarri lives in both India and the United States. She brought her daughter Khiyali to the exhibit and was surprised to find how much she already knew.

ARAVINDA PILLALAMARRI: "What I find interesting is how much of evolution she really takes for granted. For her the idea that birds have come from dinosaurs¹³ is just common knowledge and there's nothing surprising in that at all."

VOICE ONE:

Keith Leonard attends George Mason University in northern Virginia. He visited the exhibit to research Darwin's big idea.

KEITH LEONARD: "It's based on scientific observation which I think is important. And sort of the same ideas have been confirmed over and over again. I think trying to understand our world is a really complicated endeavor and it's important to have a sort of solid rational approach like science does."

VOICE TWO:

Most visitors spent a long time looking at the display called "The Tree of Life." Darwin explained the evolutionary process as the branching of a tree with complex species developing from simpler ones.

John Kress, a botanist¹⁴ and curator with the Smithsonian, says the team that created the exhibit had a different idea. He says the display was designed to look like a map of the local Washington Metro¹⁵ train system instead of a tree. The reason? All life is connected. Now we know that genetics makes this connection even deeper and we are linked to our ancestors by DNA.

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VOICE ONE:

Evolution is a theory, a word that is often used to describe an educated guess. But it is a scientific theory based on repeated observations, experiments, measurements and discoveries. A scientific theory represents the best explanation of how the natural world works.

There is almost no disagreement over the main ideas of evolution in the scientific community. But the idea that species have evolved from simpler forms is less accepted by the public. A Gallup Poll opinion study taken last February found that twenty-five percent of Americans reject evolution. Thirty-nine percent accept it and the rest have no opinion.

VOICE TWO:

Many important American court cases have dealt with evolution. The most famous took place in Tennessee in nineteen twenty-five. The trial found high school teacher John Scopes guilty of violating a state law banning the teaching of evolution. Later cases ruled that teaching religious creation stories in public schools violates the First Amendment¹⁶ of the Constitution that calls for separation of church and state.

More recently, religious groups have supported the idea of intelligent design in public schools. This is the idea that an intelligent force created all forms of life. In two thousand five, a group of high school students brought legal action against a Pennsylvania school district. Dover area schools had required that intelligent design be taught along with evolution. A United States District Court said intelligent design was not science and could not be separated from religious belief.

VOICE ONE:

But there have also been efforts to bridge the differences between religious belief and evolutionary science in recent years. Francis Collins, the director of the National Institutes of Health in Bethesda, Maryland, has attempted to do that. He is a geneticist who led the effort to map all the human genetic¹⁰ material, DNA.

Francis Collins started an organization called the BioLogos Foundation. It is meant to support the idea that traditional Christian¹⁷ beliefs can coexist with science and evolution. In two thousand six, his book, "The Language of God: A Scientist Presents Evidence for Belief," became a national best-seller.

VOICE TWO:

Hummingbirds¹⁸ and this flower, Heliconia bihai, provide an example of coevolution

One hundred fifty years after "On the Origin of Species" first appeared, it remains¹⁹ one of the most influential and debated books ever written. But it is only a beginning. John Kress of the Smithsonian says that, while science accepts evolution, debate continues.

JOHN KRESS: "We do have debates among ourselves over the exact process. And I think this is what science is about. We continually test our ideas; we continually conduct experiments to see if we can gain new insights into how life evolved and that's what really science is all about."

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VOICE ONE:

This SCIENCE IN THE NEWS was written and produced by Mario Ritter. I'm Bob Doughty.

VOICE TWO:

And I'm Doug Johnson. Visit our Web site at voaspecialenglish.com to find a link to the works of Charles Darwin. And join us again next week for more news about science in Special English on the Voice of America.

 

1 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。

2 influential   

adj.有影响的，有权势的

参考例句：

• He always tries to get in with the most influential people.他总是试图巴结最有影响的人物。
• He is a very influential man in the government.他在政府中是个很有影响的人物。

3 naturalist   

n.博物学家(尤指直接观察动植物者)

参考例句：

• He was a printer by trade and naturalist by avocation.他从事印刷业，同时是个博物学爱好者。
• The naturalist told us many stories about birds.博物学家给我们讲述了许多有关鸟儿的故事。

4 immediate   

adj.立即的；直接的，最接近的；紧靠的

参考例句：

• His immediate neighbours felt it their duty to call.他的近邻认为他们有责任去拜访。
• We declared ourselves for the immediate convocation of the meeting.我们主张立即召开这个会议。

5 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。

6 detailed   

adj.详细的，详尽的，极注意细节的，完全的

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• A detailed list of our publications is available on request.我们的出版物有一份详细的目录备索。

7 chromosome   

n.染色体

参考例句：

• Chromosome material with exhibits of such behaviour is called heterochromatin.表现这种现象的染色体物质叫做异染色质。
• A segment of the chromosome may become lost,resulting in a deletion.染色体的一个片段可能会丢失，结果产生染色体的缺失。

8 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。

9 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。

10 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。

11 naturalists   

n.博物学家( naturalist的名词复数 )；（文学艺术的）自然主义者

参考例句：

• Naturalists differ much in determining what characters are of generic value. 自然学者对于不同性状决定生物的属的含义上，各有各的见解。 来自辞典例句
• This fact has led naturalists to believe that the Isthmus was formerly open. 使许多自然学者相信这个地蛱在以前原是开通的。 来自辞典例句

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。

13 dinosaurs   

n.恐龙( dinosaur的名词复数 )；守旧落伍的人，过时落后的东西

参考例句：

• The brontosaurus was one of the largest of all dinosaurs. 雷龙是所有恐龙中最大的一种。 来自《简明英汉词典》
• Dinosaurs have been extinct for millions of years. 恐龙绝种已有几百万年了。 来自《简明英汉词典》

14 botanist   

n.植物学家

参考例句：

• The botanist introduced a new species of plant to the region.那位植物学家向该地区引入了一种新植物。
• I had never talked with a botanist before,and I found him fascinating.我从没有接触过植物学那一类的学者，我觉得他说话极有吸引力。

15 metro   

n.地铁；adj.大都市的；(METRO)麦德隆(财富500强公司之一总部所在地德国，主要经营零售)

参考例句：

• Can you reach the park by metro?你可以乘地铁到达那个公园吗？
• The metro flood gate system is a disaster prevention equipment.地铁防淹门系统是一种防灾设备。

16 amendment   

n.改正，修正，改善，修正案

参考例句：

• The amendment was rejected by 207 voters to 143.这项修正案以207票对143票被否决。
• The Opposition has tabled an amendment to the bill.反对党已经就该议案提交了一项修正条款。

17 Christian   

adj.基督教徒的；n.基督教徒

参考例句：

• They always addressed each other by their Christian name.他们总是以教名互相称呼。
• His mother is a sincere Christian.他母亲是个虔诚的基督教徒。

18 hummingbirds   

n.蜂鸟( hummingbird的名词复数 )

参考例句：

• Hummingbirds have discovered that nectar and pollen are very nutritious. 蜂鸟发现花蜜和花粉是很有营养的。
• Why do hummingbirds and gorillas both have backbones? 为什么蜂鸟和大猩猩都有脊骨？

19 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。