The reasons for the extinction of the mammoth are hotly debated in paleontology circles. One school of thought, led by Paul Martin of the University of Arizona, maintains that human overhunting wiped out the mammoths. Another theory blames disease for their demise. Since these plant communities no longer exist, scientists wonder about feeding the cloned animal. Now that might be a harder problem.
Most scientific authorities believe successful cloning is unlikely.
Agenbroad defends the effort. Some of the people who say it's impossible would have said it was impossible to clone a sheep 10 years ago too. But getting DNA undamaged by 23,000 years of time is a major problem. When they cloned Dolly the sheep, they took live cells that they cultured from the donor. And they took the nucleus from that donor and put it into an egg that had no nucleus.