Japanese scientists used cells of mice dead and frozen for 16 years . That belief would rule out the possibility of resurrecting extinct animals from their frozen remains . Feat cells allow researchers to study long - extinct species , like mammoth . Researchers used cells from mice that were frozen for 16 years at -20 Celsius .
Japanese scientists used cells of mice dead and frozen for 16 years . Feat cells allow researchers to study long - extinct species , like mammoth . Researchers used cells from mice that were frozen for 16 years at -20 Celsius .