A fossil tooth found in Russia in 2015 suggests that a small population of woolly mammoths may still have existed as recently as 4,300 years ago.
Scientists can determine a woolly mammoth's age by looking at the rings in its tusks, much like tree trunk rings.
The woolly rhinoceros co-existed with the woolly mammoth.
Mammoth tusks could range from 10-13 feet in length.
The lumps on a woolly mammoth's back were extra stores of fat to help the animal survive the winter.