The team's findings also suggested that there were two major population declines in mammoth history. One probably occurred 250,000 to 300,000 years ago. The other most likely took place around 12,000 years ago, at the end of the last Ice Age
Used soft tissue from a young male that lived in northeastern Siberia around 44,800 years ago, and a large tooth from a Wrangel Island male mammoth that lived about 4,300 years ago.
By comparing the two copies in each mammoth and noting when they were exactly the same and when they were not, the scientists were able to estimate how closely related the mammoths’ parents were. More closely related parents are more likely to contribute DNA molecules that are exactly the same.