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大学英语综合教程 第三册 8textA
日期:2009-12-07
[00:00.00]Cloning offers the possibility of making exact copies of ourselves.
[00:05.30]Should this be allowed? What benefits and dangers may cloning bring?
[00:10.92]A CLONE IS BORN                By Gina Kolata
[00:15.62]On July 5, 1996, at 5:00 p.m., the most famous lamb in history entered the world.
[00:23.64]She was born in a shed,
[00:26.28]just down the road from the Roslin Institute in Roslin, Scotland,
[00:31.74]where she was created. And yet her creator,
[00:36.52]Ian Wilmut, a quiet, balding fifty-two-year-old embryologist, does not remember
[00:44.07]where he was when he heard that the lamb,named Dolly, was born.
[00:49.84]He does not even recall getting a telephone call from John Bracken, a scientist
[00:56.50]who had monitored the pregnancy of the sheep that gave birth to Dolly,
[01:02.09]saying that Dolly was alive and healthy and weighed 6.6 kilograms.
[01:09.04]2 No one broke open champagne. No one took pictures.
[01:14.21]Only a few staff members from the institute and a local veterinarian
[01:20.27]who attended the birth were present.
[01:23.59]Yet Dolly, who looked for all the world like hundreds of other lambs
[01:29.31]that dot the rolling hills of Scotland,was soon to change the world.
[01:35.37]3 When the time comes to write the history of your age, this quiet birth,
[01:41.51]the creation of this little lamb,will stand out.
[01:46.11]The world is a different place now that she is born.
[01:50.58]4 Dolly is a clone. She was created not out of the union of a sperm and an egg
[01:58.07]but out of the genetic material from an udder cell of a six-year-old sheep.
[02:04.42]Wilmut fused the udder cell with an egg from another sheep,
[02:09.59]after first removing all genetic material from the egg.
[02:14.87]The udder cell’s genes took up residence in the egg
[02:19.23]and directed it to grow and develop. The result was Dolly,
[02:25.14]the identical twin of the original sheep that provided the udder cells,
[02:30.99]but an identical twin born six years later.
[02:36.21]5 Until Dolly entered the world, cloning was the stuff of science fiction.
[02:41.80]It had been raised as a possibility decades ago,then dismissed,
[02:47.68]something that serious scientists thought was simply not going to happen anytime soon.
[02:53.92]Now it is not fantasy to think that someday, perhaps decades from now,
[03:00.19]but someday, you could clone yourself and make tens,dozens,
[03:06.38]hundreds of genetically identical twins.
[03:10.62]Nor is it science fiction to think that your cells could be improved beforehand,
[03:17.15]genetically engineered to add some genes and remove others.
[03:22.53]6 True, it was a sheep that was cloned, not a human being.
[03:28.12]But there was nothing exceptional about sheep.
[03:31.96]Even Wilmut, who made it clear that he was opposed to the very idea of cloning people,
[03:38.54]said that there was no longer any theoretical reason
[03:43.24]why humans could not clone themselves, using the same methods
[03:48.78]he had used to clone Dolly.
[03:51.71]“There is no reason in principle why you couldn’t do it.”
[03:56.15]But, he added, “All of us would find that offensive.”
[04:00.85]7 We live in a time when we argue about pragmatism and compromises
[04:06.65]in our quest to be morally right.
[04:09.97]But cloning forces us back to the most basic questions that have plagued humanity
[04:16.31]since the dawn of recorded time:
[04:19.79]What is good and what is evil?And how much potential for evil can we tolerate
[04:27.86]to obtain something that might be good?
[04:31.57]Cloning, with its possibilities for creating our own identical twins,
[04:37.24]brings us back to the ancient sins of vanity and pride;
[04:42.36]the sins of Narcissus, who so loved himself, and of Prometheus, who, in stealing fire,
[04:51.21]sought the powers of God.So before we can ask
[04:56.57]why we are so fascinated by cloning, we have to examine our souls and ask,
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