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Vocabulary: Genetics 詞匯:遺傳學(xué),基因?qū)W

Will this be a future sight in North America?

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A team of international scientists has published the complete genome of the woolly mammoth - a creature which became extinct thousands of years ago.

The study, published in the Journal Current Biology, will probably cheer up a team of Harvard University researchers who've been planning to add mammoth genes to the stem cells of elephants. Their aim is to find out how the mammoth's adaptations helped them survive the ice ages.

The Long Now Foundation, based in San Francisco, is financing the Harvard team and has daring plans for the future if the species is resurrected. It says on its website that its goal is "to produce new mammoths that are capable of repopulating the vast tracts of tundra and boreal forest in Eurasia and North America."

They say: "The goal is not to make perfect copies of extinct woolly mammoths, but to focus on the mammoth adaptations needed for Asian elephants to live in the cold climate of the tundra."

But how close are we from a Jurassic-Park-like scenario in which extinct animals are brought back to life? Very far, according to some experts. Professor Beth Shapiro, of the University of California, Santa Cruz, wrote a book called How to Clone a Mammoth. She is sceptical and believes there is an enormous difference between an embryo in a lab dish and a living animal with some of the characteristics of a mammoth. And we can't even be sure if the elephant's surrogate pregnancy would be successful.

Woolly mammoths died out some 4,000 years ago. It might take a long time before the fantasy of the Steven Spielberg movies is turned into reality. And that's fine for those of us who can remember that the resurrected dinosaurs on the screen gave the humans a pretty hard time. If mammoths come back, maybe it would be a good idea to start running...

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