Most of what we know about other extinct, prehistoric animals comes from the fossil record, mainly from bones and teeth. For several reasons, we know the most about mammoths:
* They were relatively abundant. Indeed, there was so much ivory in Northern Asia that a trade in fossil mammoth tusks began in the Middle Ages that is still ongoing in Russia.
* Well-preserved carcasses have been found. A significant number of remarkably intact mammoths have been preserved in the Siberian permafrost and also in tar pits and dry caves further south.