section_path: Artificial insemination
section_name: Artificial insemination
paragraph_text: Artificial insemination
  
  A second method involves artificially inseminating an elephant egg cell with sperm cells from a frozen woolly mammoth carcass. The resulting offspring would be an elephant–mammoth hybrid, and the process would have to be repeated, so more hybrids could be used in breeding. After several generations of cross-breeding these hybrids, an almost pure woolly mammoth would be produced. Whether the hybrid embryo would be carried through the two-year gestation is unknown; in one case, an Asian elephant and an African elephant produced a live calf named Motty, but it died of defects at less than two weeks old. There is also another fact to consider, that sperm cells of modern mammals are viable for 15 years at most after deep-freezing. This makes this method unfeasible.