One of the most famous and well-known megafauna of North America, the Woolly Mammoth (Mammuthus primigenius) lived during the Pleistocene, 2.6 million years ago, until they went extinct during the last ice age, approximately 10,000 years ago.

Woolly Mammoths only had four functional molars at a time- two in their upper jaw and two in their lower. The crown of the tooth was continuously pushed upward as it was worn down by their diet of coarse tundra grasses. Their teeth had up to 26 separated ridges of enamel, which were quite wear-resistant considering the wear-and-tear the teeth went through. Throughout their lifetime, an adult mammoth would go through five to six sets of molars, each set larger and with more ridges than the previous set. Woolly Mammoths are considered to have had the most complex molars of any elephant.