2019-2020年高中英语 Module 6 Animals in Danger Special new experiment训练 外研版必修5.doc

2019-2020年高中英语 Module 6 Animals in Danger Special new experiment训练 外研版必修5Its cutting-edge and controversial.But there is a new proof that the cloning of the endangered species just might work.A rare Asian calf born on an Iowa farm is possiblly the first healthy animal cloned from the endangered species.Our Peter Standring has the story.In the heart of the midwest where dairy farms and cattle dominate the landscape, and an exotic breed cow has got everyone talking. It is a rare Asian calf known as a banteng(班腾野牛), born recently in this Iowa research farm.The calf is nursing at regular intervals, he is bright, alert. By all accounts, he can get up and down by himself and we are very hopeful that he will go on to live a normal life.The story of this unique animal begins in California, at the San Diego wild animal park banteng breeding program. In 1980, an adult male died without producing any offspring, so researchers at the zoo froze some of bantengs skin cells, hoping one day to put them to good use. They were into the Frozen Zoo. Its a deep freeze menagerie(动物园) of some of the rarest animals on earth.3200 in all. Their genetic information is preserved in 4 tanks, kept at -320We used to have a poster on the wall in here, it was said that you must collect things for reasons that you do not yet understand. So we collect as many samples as possible, whenever we can, and we put them in here. They potentially will stay there for many, many, many generations, 2 or 3 hundred years.Last year, the bantengs skin cells were removed from the Frozen Zoo and sent to the Advanced Cell Technology Lab in Western Massachusetts. The bantengs DNA was transferred into the eggs of ordinary beef cows; the fertilized eggs were then implanted into several surrogate（代孕）mothers.While Scientists believe that this type of cross-species cloning holds great promise, but it is not as simple as it seems. Two years ago, Advanced Cell cloned a rare Asian ox known as a gaur（亚洲野牛）. It was hailed as the first birth of cloned endangered animal. The gaur died less than two days after the birth. Despite that setback, scientists insisted that birth was a proof-cloning could work .Now, their determination and patience could pay off. The long-term survival of the baby banteng would bode（预示） well for his and other endangered species whose numbers could hypothetically be boosted by this brave new experiment.