But recent news reveals that we may not even have to keep our fingers crossed about their existence any more. Because one group of scientists have succeeded in "resurrecting" the Thylacine's gene:
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In what they describe as a world first, researchers from Australian and U.S. universities extracted a gene from a preserved specimen of the dog-like marsupial - formally known as a thylacine - and revived it in a mouse embryo.
"This is the first time that DNA from an extinct species has been used to induce a functional response in another living organism," said research leader Andrew Pask of the University of Melbourne.
The announcement was hailed as raising the possibility of recreating extinct animals. Mike Archer, dean of science at the University of New South Wales, who led an attempt to clone the thylacine when he was director of the Australian Museum, called it "one very significant step in that direction." "I'm personally convinced this is going to happen," he told the Australian Broadcasting Corporation. "I've got another group working on another extinct Australian animal and we think this is highly probable."
"We hope that with advances in techniques that maybe one day that might be possible, but certainly as science stands at the moment, we are not able to do that, unfortunately," he said.
Well I'm not so sure that is so unfortunate. Although I do agree with the notion of say bringing back species that were lost because of our own human intervention - i.e. the Thylacine, or the Passenger Pigeon, or the Dodo - its an entirely different ballgame to dabble in the DNA of groups of creatures for which the Earth is just not suited for any more.
Where on Earth would you house a pack of marauding T-rexs? And what kind of food provisions would you have to make for a herd of ravenous Diplodicus?
Are we really ready to deal with such collosal heachaches when we are already making a mess of trying to mamage our present day environment???