Dimetrodon (meaning: two events of teeth), was a rapacious synapsid (mammal-like reptile) genus that flourished during the Permian age (before dinosaurs evolved) and was a carnivore. It most likely ate other pelycosaurs (its close relatives), insects and other animals.

It lived between 280 and 265 million years back. It was more intimately related to mammals than to true reptiles (Sauropsida), such as dinosaurs, lizards and birds. Dimetrodon was not a dinosaur, although being popularly grouped with them. It is properly classified as a pelycosaur (primitive Late Paleozoic synapsid amniotes and connections of warm-blooded mammals).

Dimetrodon was an apex predator (predators that, as adults, are not generally preyed upon in the wild in important parts of their ranges), and was among the biggest of its day. Dimetrodon grew to up to 3 metres (9.8 feet) in length and weighed approximately 550 pounds (250 kg). It had a big spiny sail along its back which was a flap of skin dense with blood vessels and walked on four side-sprawling legs, it may have moved in a manner alike to present-day lizards. The sail was supported by long, bony spines, each of which grew out of a divide spinal vertebra (a bone in the back). The sail may have been a thermoregulatory structure, used to absorb and liberate heat. The sail may have also been used for mating and dominance rituals and for making it look much bigger than it was to ward off potential predators.

The term two measures of teeth refer to the reality that it had a large skull with two different types of teeth (shearing teeth and sharp canine teeth), not like reptiles.

Dimetrodon was a dominant carnivore during the Permian age, living mostly in swampy areas. Unlike their fellow non-finned pelycosaurs, they warmed up premature after sunrise and cooled off more professionally during the heat of the day. This efficient thermoregulation along with their big and powerful jaws gave them the advantage making them dominant over their fellow creatures. They were most likely very fast runners.


Fossils of Dimetrodon have been establish in North America and Europe. The climate of Europe and North America in the premature Permian, was probably arid to continental, so Dimetrodon was probably adjustable. Trackways (fossilized footprints) of Dimetrodon have been establish in Nova Scotia, Canada.

Dimetrodon went extinct in the enormous Permian extinction, 245 million years ago, which instantaneously preceded the Mesozoic Era.

Scientific Classification:

Kingdom: Animalia

Phylum: Chordata

Class: Synapsida

Order: Pelycosauria

Family: Sphenacodontidae

Genus: Dimetrodon