It is a fascinating prospect, one that was raised again last week when the most recently discovered carcass of a mammoth was revealed to the public in Yokohama, Japan.

The female, thought to have been around 50 when she died, had lain frozen in the ground for tens of thousands of years. Yet she still had hair, muscle tissue, and possibly blood. Samples have now been sent to South Korea, where scientists say they are planning to use them to clone a mammoth, though the proposal is considered to be highly controversial.

"The hunt for mammoth corpses has been transformed in recent years," said Professor Adrian Lister, of the Natural History Museum, London, and one of the advisers for the museum's current "Extinction" exhibition. "We have found as many mammoths in the past five years as we did in the previous 50, partly because global warming is melting the Siberian permafrost and is revealing more and more bodies and partly because local people realise it is a lucrative business. Mammoth ivory is viewed as a legal and ethically acceptable alternative to elephant tusks.

"The only trouble is that every time a new well-preserved mammoth is found, people also repeat the claim that we will soon be able to clone them, and I very much doubt that we will."

Mammoths ranged from the British Isles to eastern Asia and northern America until they disappeared around 10,000 years ago, though one small population was recently found to have survived to around 4,000 years ago on the Russian island of Wrangel.

Hunting by cavemen or climate change, or a combination of the two, are generally blamed for their demise.

Now some scientists are talking openly of bringing them back to life. Yokohama mammoth samples have been sent to the private laboratory of the disgraced South Korean cloning expert Hwang Woo-suk, who is co-operating with Russian scientists with the specific aim of recreating mammoths. Similarly, Semyon Grigoriev, who led the team that excavated the mammoth, has speculated that fluid found near the creature may be blood that contains intact cells which could be used to bring about their resurrection. "This find gives us a really good chance of finding living cells, which can help us implement this project to clone a mammoth," said Grigoriev.