Resurrecting woolly mammoth cells is hard to do

Biological activity seen in an experiment may be more mouse than mammoth, one cloning expert says

Siberian mammoth

UNFROZEN  Scientists in Japan found some mostly intact DNA-containing compartments called nuclei in the cells of this Siberian mammoth that was frozen for 28,000 years.

Cyclonaut/Wikimedia Commons (CC BY-SA 4.0)

Proteins from woolly mammoth cells frozen for 28,000 years in the Siberian tundra may still have some biological activity, claim researchers attempting to clone the extinct behemoths.