DIMETRODON
Living around 280 to 255 million years ago, this synapsid reptile could reach up to 3 metres long. Dimetrodon flourished in the dry climate of the Permian period thanks to its waterproof skin capable of holding moisture, paired with the iconic sail rising from its back. Dimetrodon had careful control over its body temperature, the purpose of the sail was to increase the surface area of the animal, allowing more heat to escape on hot days, and heat to be absorbed on cold days, it was able to do this as it was packed with blood vessels to transfer heat. The sail of Dimetrodon really was a remarkable feature of animals in the Permian, amongst the rest of the animal community, Dimetrodon would certainly have stood out. This had led to speculation that a Dimetrodon’s sail did more than regulate its temperature, but also allowed members of the species to recognise each other and the sail may certainly have played a part in mating rituals.
How Dimetrodon hunted is still not fully understood, although they were certainly meat eaters. Due to the purpose of the sail, it is commonly suggested that Dimetrodon warmed up in the early hours of the morning so they would be active enough to hunt midday, they would then cool off during the heat of the afternoon. It is thought that they used their acute senses of sight and smell to select prey and stalk them, yet it may have been capable to swipe prey from shallow rivers and swamp areas. Dimetrodon is seen as one of the most successful predators of its time, fossils show this reptile was one of the first animals to showcase teeth of different sizes and shapes. The name Dimetrodon quite literally means “two-measure teeth”, sharp canines and shearing teeth. It also had a high skull and relatively short snout to clamp down on prey with great force where its dagger-like canines would pierce through flesh.
Dimetrodon is commonly thrown in with the dinosaurs in books or plastic children toys, yet Dimetrodon lived 40 million years before even the first dinosaurs appeared and they are in fact more closely related to mammals. The species is classified as a pelycosaur, which were reptiles with very primitive mammalian characteristics, essentially pelycosaurs were the predecessors of more mammal like reptiles, known as therapsids. Fossils of Dimetrodon are relatively common, many specimens have been found in North America, yet they’ve also been found in Europe and Russia. The sails of many specimens have been found in exquisite condition, even some footprints have been discovered.
Sadly, the Permian era was counting down to a violent end. Over thousands of years the climate grew hotter and deserts began to spread across the globe. Although Dimetrodon could deal with heat, an extinction was looming. Around 256 million years ago, Dimetrodon disappeared, and it wouldn’t be long before 90% of life on Earth followed.
