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New research indicates they are at least twice as old, living between 25,000 and 55,000 years ago, with one of them 'perfectly' preserved.

Extinct Lion Cubs Found in Siberia are up to 55,000 Years Old - Latest Test Results Reveal

By The Siberian Times Reporter Tantalizing studies are now underway to establish if one of two lion cub carcasses preserved by permafrost has traces of the world's oldest mother's milk. The lion cubs...
'We managed to take some samples of skin along with the muscle tissue, and we hope that we will find what we want in these samples.'

South Koreans Kick Off Efforts to Clone Extinct Siberian Cave Lions

By: The Siberian Times reporter Samples taken from cubs frozen in permafrost for at least 12,000 years. Two infant prehistoric big cats - dating from Pleistocene times - were found in a 'sensational...