MANY of us remember being in awe （敬畏） when we saw cloned dinosaurs （恐龙） running wild in the film Jurassic Park．And the idea of using technology to revive （恢复） extinct species has long fascinated not only writers and directors，but scientists as well．

According to The Telegraph，woolly mammoths （长毛猛犸象），which featured in the popular Ice Age animated movie series，"may walk the earth once more"now that scientists have taken another step toward realizing a long-held dream-recreating their DNA．

Mammoths became extinct around 10，000years ago．However，since the discovery of near-perfect preserved remains in Arctic permafrost （北极冻土带） in May 2013，a variety of research studies have been carried out since．

Geneticists from Harvard University analyzed DNA from the remains，looking for genes which separated mammoths from elephants，such as hairiness and ear size．They then used the results to reproduce exact copies of 14mammoth genes．"It is the first time that mammoth genes have been alive-although so far it has only been done in the lab，"George Church，lead researcher of the project，told the Sunday Times．

Church then used a new technique which allows scientists to edit DNA carefully，replacing sections of elephant DNA with the mammoth genes．So"we now have functioning （正常运行的） elephant cells with mammoth DNA in them，"he said．

However，Church ruled out the possibility of bringing the mammoths back to life via cloning from frozen remains．He said he"preferred to focus on rebuilding the full mammoth genome by analyzing DNA from preserved remains and putting it into the cells of its closest living relative-the Asian elephant，"reported The Telegraph．

Church argued that the return of the woolly mammoth-or rather，the return of something very similar-could help bring back fragile （脆弱的） ecosystems．However，some scientists believe that bringing back the mammoth would be unethical．

Professor Alex