PERMIAN MASS EXTINCTION SERIES 1: PERMIAN ANIMAL 1) DIMETRODON

 

Dimetrodon was a sail‑backed, carnivorous synapsid that lived in the Early–Middle Permian about 294–271 million years ago; it is not a dinosaur but is more closely related to mammals, and is best known for the tall neural‑spine “sail” on its back.

Quick facts

Scientific group: Synapsida (basal synapsids, traditionally called pelycosaurs).

Time period: ~294–271 million years ago (Permian).

Typical size: Most species 1.7–4.6 m (5.6–15.1 ft) long; weight roughly 28–250 kg depending on species.

Diet and posture: Carnivorous, obligate quadruped with a tall, curved skull and differentiated teeth (large caniniforms and shearing teeth).

Distinctive features

The sail: Formed by greatly elongated neural spines projecting from the vertebrae and likely supported a skin membrane; proposed functions include thermoregulation, display/social signaling, and species recognition.

Skull and teeth: Heterodont dentition (teeth of different sizes) and strong jaw musculature indicate an active predator capable of subduing relatively large prey.

Relationship to mammals: Although reptile‑like in appearance, Dimetrodon is on the synapsid line that ultimately leads to mammals, making it closer to mammals than to modern reptiles or dinosaurs.

DIMETRODON FOSSIL

DIMETRODON FOSSIL

Paleogeography and fossils

Main fossil localities: Red Beds of Texas and Oklahoma (USA) are the richest sources; fossils have also been found in Germany.

Not a dinosaur: Dimetrodon became extinct tens of millions of years before dinosaurs appeared; it is often misportrayed in popular media as a dinosaur.

DIMETRODON AND LYSTROSAUR

Why it matters

Evolutionary significance: Dimetrodon helps illustrate early synapsid diversity and the anatomical trends (skull openings, differentiated teeth) that foreshadow later therapsids and ultimately mammals.

Public recognition: Its sail and distinctive silhouette make it one of the most recognizable Permian vertebrates and a common feature in museum exhibits and educational materials.

DIMETRODON 3DMAX FILE