英语听力：自然百科 重现人间的斑驴
时间：2018-12-26 作者：英语课 分类：自然百科2008年
英语课
The plains zebra is a close relative of the quagga, extinct since 1883. But according to members of the Quagga Project in Cape 1 Town, South Africa. The foal seen running with its herd 2 of plains zebras is a quagga. His name's Harley and he was born in May of this year. Prior to this, the most quagga-like animal was born in 2005. Conservationists on the project have used selective breeding with southern plains zebras to try to recreate a subspecies that has been extinct for more than 100 years.
“The quagga, is actually a subspecies of the plains zebra. Therefore, the main gene 3 pool still exists within the plains zebra.”
The selective breeding program uses plains zebras that have quagga-like traits, an approach that livestock 4 and horse breeders have used for centuries.
“‘Cause (what) I understand is you cannot bring anything back from extinction 5, but you can revive its best subspecies.”
It's an opinion shared by zoologist 6 Peter Lyord, who says that other genetically 7 coded features such as habitat adaptations, unique to the quagga could not be recreated in the new quagga breed.
“So it would be very unfair to say you have recreated the quagga, and there is also a danger. Er, and the danger is that you could create the wrong impression to people and say once an animal is extinct. Don't worry, we can always recreate it. This is a special set of circumstances. There are several subspecies. What these people are doing is they’re using one of the subspecies, er, and, its lack of striping in certain individuals to try and produce an animal that looks similar in external appearance to the quagga.”
Critics say it is impossible to know whether animals produced are true quagga, since they were never studied by modern science. Aside from color and stripes, no other defining quagga characteristics, such as behavioral patterns or diet were ever noted 8 and may have been lost to history.
1 cape
n.海角，岬；披肩，短披风
- I long for a trip to the Cape of Good Hope.我渴望到好望角去旅行。
- She was wearing a cape over her dress.她在外套上披着一件披肩。
2 herd
n.兽群，牧群；vt.使集中，把…赶在一起
- She drove the herd of cattle through the wilderness.她赶着牛群穿过荒野。
- He had no opinions of his own but simply follow the herd.他从无主见，只是人云亦云。
3 gene
n.遗传因子，基因
- 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 livestock
n.家畜，牲畜
- Both men and livestock are flourishing.人畜两旺。
- The heavy rains and flooding killed scores of livestock.暴雨和大水淹死了许多牲口。
5 extinction
n.熄灭，消亡，消灭，灭绝，绝种
- The plant is now in danger of extinction.这种植物现在有绝种的危险。
- The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。
6 zoologist
n.动物学家
- Charles darwin was a famous zoologist.查尔斯达尔文是一位著名的动物学家。
- The zoologist had spent a long time living with monkeys.这位动物学家与猴子一起生活了很长时间。
7 genetically
adv.遗传上
- 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