VOA标准英语2009年-Scientists Use DNA to Trace Illegal Elepha

Scientists are using DNA¹ to trace illegal ivory from slaughtered² elephants to its countries of origin in an effort to nab poachers. Researchers are trying to combat the multi-billion dollar criminal enterprise at its source.
　
A poached elephant

Since enacting³ the U.N. treaty outlawing⁴ the hunting of endangered elephants for their tusks⁵ in 1989, experts say illegal poaching of African elephants has only increased. The illicit⁶ ivory trade has been a bonanza⁷ for international crime syndicates, with the prized tusks fetching as much as $1,800 per kilogram on world markets.

Demand for ivory has been especially high in China. There is also a substantial market for illegal ivory in the United States and in Japan, where it is commonly fashioned into handles for knives and swords.

To combat poaching, scientists are using the genetic⁸ material from the tusks of slaughtered elephants to trace the ivory back to the countries where it originated. They have developed a method for extracting DNA from tiny samples of ivory given to them by authorities in countries where tusks have been confiscated⁹.
　
Another poached elephant

That DNA is then compared to a catalog of unique DNA samples taken from elephant dung in regions throughout Africa.

The head of the Center for Conservation Biology at the University of Washington in Seattle, Samuel Wasser, says researchers have pinpointed¹¹ the origins of thousands of kilograms of illegal ivory smuggled¹² out of Africa, and their evidence makes clear the terrible impact poaching is having on endangered wild elephant populations:
　
An ivory market in central Africa

"People thought the only way they are getting that much ivory is by essentially¹³ cherry picking across Africa; going and taking a little from this dealer¹⁴ and that dealer, etc., pulling it together in a common location and shipping¹⁵ it out," said Samuel Wasser. "And what we showed is that for these large seizures¹⁷, that is not what is happening. What is happening is that they ... are all coming from pretty much the same location. So, they are hammering this population [of elephants] over and over and over again, and it looks like the big dealers¹⁸ are putting out purchase orders, saying I need this many cuts by this date, and then they go and hammer this population over and over to get it to them."
　
An adult and a young elephant smelling the femur bone of a dead elephant

Wasser says DNA fingerprinting¹⁹ helped investigators²⁰ three years ago to make the largest seizure¹⁶ of illegal ivory since the global trade ban went into effect in 1989 - 10 tons of ivory contained in two separate shipments. All of the ivory was traced to a small area near the border of Tanzania and Mozambique.

Wasser says illegal ivory is usually shipped to a number of countries before reaching its final destination in order to avoid detection and protect international dealers.

But the use of DNA, according to Wasser, makes it possible to pinpoint¹⁰ precisely²¹ where the ivory comes from when it is finally seized so efforts can be made to stop poachers.

"It allows us to direct limited law enforcement resources to key areas," he said. "It also tends to expose countries in denial [about] the amount of poaching going on in their country and to essentially encourage them to get more serious about policing the illegal trade."

An article on the use of DNA fingerprinting to combat the illegal ivory trade, by Samuel Wasser and fellow researchers at the University of Washington, appears in the July issue of Scientific American.

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 slaughtered   

v.屠杀，杀戮，屠宰( slaughter的过去式和过去分词 )

参考例句：

• The invading army slaughtered a lot of people. 侵略军杀了许多人。 来自《简明英汉词典》
• Hundreds of innocent civilians were cruelly slaughtered. 数百名无辜平民遭残杀。 来自《简明英汉词典》

3 enacting   

制定（法律），通过（法案）( enact的现在分词 )

参考例句：

• Generally these statutes apply only to wastes from reactors outside the enacting state. 总之，这些法令只适宜用在对付那些来自外州的核废料。 来自英汉非文学 - 环境法 - 环境法
• In addition, the complexion of enacting standards for live working is described. 另外，介绍了带电作业标准的制订情况。

4 outlawing   

宣布…为不合法（outlaw的现在分词形式）

参考例句：

• Regulations are outlawing certain refrigerants, such as chlorofluorocarbons, which contain ozone-depleting chemicals. 随后出台的政策禁用了部分制冷剂，如破坏臭氧层的氟氯碳化合物。
• An amendment outlawing sale of intoxicating liquors(1920)was repealed in 1933. 规定售卖酒类为非法的一个宪法修正案（一九二○年）在一九三三年被废止。

5 tusks   

n.（象等动物的）长牙( tusk的名词复数 )；獠牙；尖形物；尖头

参考例句：

• The elephants are poached for their tusks. 为获取象牙而偷猎大象。
• Elephant tusks, monkey tails and salt were used in some parts of Africa. 非洲的一些地区则使用象牙、猴尾和盐。 来自英语晨读30分（高一）

6 illicit   

adj.非法的，禁止的，不正当的

参考例句：

• He had an illicit association with Jane.他和简曾有过不正当关系。
• Seizures of illicit drugs have increased by 30% this year.今年违禁药品的扣押增长了30%。

7 bonanza   

n.富矿带，幸运，带来好运的事

参考例句：

• Bargain hunters enjoyed a real bonanza today.到处买便宜货的人今天真是交了好运。
• What a bonanza for the winning ticket holders!对于手持胜券的人来说，这是多好的运气啊。

8 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。

9 confiscated   

没收，充公( confiscate的过去式和过去分词 )

参考例句：

• Their land was confiscated after the war. 他们的土地在战后被没收。
• The customs officer confiscated the smuggled goods. 海关官员没收了走私品。

10 pinpoint   

vt.准确地确定；用针标出…的精确位置

参考例句：

• It is difficult to pinpoint when water problems of the modern age began.很难准确地指出，现代用水的问题是什么时候出现的。
• I could pinpoint his precise location on a map.我能在地图上指明他的准确位置。

11 pinpointed   

准确地找出或描述( pinpoint的过去式和过去分词 )； 为…准确定位

参考例句：

• His refusal to help simply pinpointed his cowardice. 他拒绝帮助正显示他的胆小。
• Computers pinpointed where the shells were coming from. 计算机确定了炮弹发射的位置。

12 smuggled   

水货

参考例句：

• The customs officer confiscated the smuggled goods. 海关官员没收了走私品。 来自《现代汉英综合大词典》
• Those smuggled goods have been detained by the port office. 那些走私货物被港务局扣押了。 来自互联网

13 essentially   

adv.本质上，实质上，基本上

参考例句：

• Really great men are essentially modest.真正的伟人大都很谦虚。
• She is an essentially selfish person.她本质上是个自私自利的人。

14 dealer   

n.商人，贩子

参考例句：

• The dealer spent hours bargaining for the painting.那个商人为购买那幅画花了几个小时讨价还价。
• The dealer reduced the price for cash down.这家商店对付现金的人减价优惠。

15 shipping   

n.船运（发货，运输，乘船）

参考例句：

• We struck a bargain with an American shipping firm.我们和一家美国船运公司谈成了一笔生意。
• There's a shipping charge of ￡5 added to the price.价格之外另加五英镑运输费。

16 seizure   

n.没收；占有；抵押

参考例句：

• The seizure of contraband is made by customs.那些走私品是被海关没收的。
• The courts ordered the seizure of all her property.法院下令查封她所有的财产。

17 seizures   

n.起获( seizure的名词复数 )；没收；充公；起获的赃物

参考例句：

• Seizures of illicit drugs have increased by 30% this year. 今年违禁药品的扣押增长了30%。 来自《简明英汉词典》
• Other causes of unconsciousness predisposing to aspiration lung abscess are convulsive seizures. 造成吸入性肺脓肿昏迷的其他原因，有惊厥发作。 来自辞典例句

18 dealers   

n.商人( dealer的名词复数 )；贩毒者；毒品贩子；发牌者

参考例句：

• There was fast bidding between private collectors and dealers. 私人收藏家和交易商急速竞相喊价。
• The police were corrupt and were operating in collusion with the drug dealers. 警察腐败，与那伙毒品贩子内外勾结。

19 fingerprinting   

v.指纹( fingerprint的现在分词 )

参考例句：

• Institutions from banks to pawnshops are fingerprinting to authenticate transactions. 从银行到当铺，都在使用指纹识别对交易进行验证。 来自互联网
• In addition, a digital fingerprinting algorithm based on binary codes is described. 介绍了一种二进制指纹编码方案。 来自互联网

20 investigators   

n.调查者，审查者( investigator的名词复数 )

参考例句：

• This memo could be the smoking gun that investigators have been looking for. 这份备忘录可能是调查人员一直在寻找的证据。
• The team consisted of six investigators and two secretaries. 这个团队由六个调查人员和两个秘书组成。 来自《简明英汉词典》

21 precisely   

adv.恰好，正好，精确地，细致地

参考例句：

• It's precisely that sort of slick sales-talk that I mistrust.我不相信的正是那种油腔滑调的推销宣传。
• The man adjusted very precisely.那个人调得很准。