Both are extinct proboscideans, but they are not close relatives. Mammoths were closely related to modern elephants and grazed on grass, with high-crowned ridged teeth. Mastodons belonged to an older, more distant branch, were stockier and browsed on leaves and twigs, with distinctly cone-shaped teeth.
The core difference
Two different lineages, separated by tens of millions of years and by diet.
- mammoth — closely related to modern elephants; taller, ridged grinding teeth; grazer.
- mastodon — an older, separate branch; stockier and lower; cone-shaped teeth; browser.
The teeth are the giveaway
Mastodon literally means "nipple tooth", from Greek — a description of the cone-shaped cusps on its molars, which suit crushing twigs. Mammoth teeth are ridged plates for grinding grass, like a modern elephant's. Palaeontologists can tell the two apart from a single molar.
The woolly one
The woolly mammoth is the famous hairy one, adapted to the ice-age steppe. Mastodons had hair too, but the popular image of the shaggy tusked giant is a mammoth.
