英語聽力：自然百科 重現(xiàn)人間的斑驢

　　The plains zebra is a close relative of the quagga, extinct since 1883. But according to members of the Quagga Project in Cape Town, South Africa. The foal seen running with its herd 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 pool still exists within the plains zebra.”

　　The selective breeding program uses plains zebras that have quagga-like traits, an approach thatlivestock and horse breeders have used for centuries.

　　“‘Cause (what) I understand is you cannot bring anything back from extinction, but you can revive its best subspecies.”

　　It's an opinion shared by zoologist Peter Lyord, who says that other genetically 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 and may have been lost to history.