The animal with the earliest sexual differentiation.

Name: diictodon (DY-ik-toe-don) means two teeth
animal: therapsid reptile
size: 45 cm long
diet: herbivore
lived: 256 - 252 mya
found: Africa and Asia
fossil:

In the late Permian period, the same time as the gorgonopes, these extremely common mammal-like synapsids burrowed deep in the ground living in couples, probably staying with the same partner its entire life. It’s head was large, with a beak that had no teeth except two saber like tusks. The tusks are extremely important as they are the characteristic of the first sexual dimorphism in all of animal history. Only the males were found having the pair of tusks. It lived in deep narrow tunnels protecting it from harsh weather and larger predators - making it an extremely successful animal of its time.

The diictodon were abundant, not only would you find multiple burrows within the same patch of land, their fossils also make up about 1/2 of all backboned animals in South Africa from the Late Permian Period. None of the burrows were interconnected further stressing the theory that the diictodon were strictly monogamous. A small chamber at the end of the burrow would have vegetation for comfort, this is where the diictodon female would have and raise her children.

These underground burrows would have been excellent for times of drought. The burrows would have remained cooler, and had a damp environment. The diictodon could also feed on the roots that were underground. The animals would, however, build their burrows in areas that were not so great, such as river banks. They burrows would often flood killing the animals. The particular fossil above is a pair of diictodon that were cuddled together when flood struck.

The diictodon’s arms and legs did not lack in strength, still they were strictly herbivores. It had an excellent sense of balance, sight and smell. It would use these keen senses to dart in and out of its burrow knowing danger was not near. It would then use its beak to break of vegetation and other plant pieces to eat and use in their housing.

The diictodon is widely studied since it is such an abundant animal. Not only was it the first animal with sexual differentiation, it was also the missing link between reptiles becoming mammals. This little reptile is thus a hugely important link in the evolutionary chain.

The finding of the sexual dimorphism led scientists to believe there was an extremely complex set of social behaviors within the diictodon community. They could have been used to combat other males in an attempt to find a mate, or could have been used ritualistically.  These tusks gave rise to unbelievably huge developments in mammals in the near future.

With a name like “Gorgonops” I expected it to look more sci-fi-ish.

Name: Gorgonops (gore-gon-ops) “Gorgon’s arch”
Animal type: Therapsid reptile
lived: 252 - 248 mya
diet: Carnivore
size: 3.5 meters
found: Africa
fossil:

The Earth was slowly dying as it Pangaea died up from coast to coast, temperatures were getting higher and higher very quickly and rainfall became more and more scarce. In these harsh conditions few animals were surviving. The gorgonops was preying on anything that was left. It was a gigantic carnivorous reptile, the size of an elephant but moving sleek and quickly like a fox. It had large, long and sharp teeth permitting it to take down large animals with its strong jaw. It also had two long saber teeth, one of the first animals to have such a thing.

The gorgonops was extremely well adapted for life in these harsh conditions. Its long and upright legs allowed it to walk and run efficiently while it’s keen eye sight and sense of smell made it a very dangerous predator. The animals probably lived in groups, hunting during the cooler times of day and resting in the shade at peak hours. It would have taken several of the animals to take down the larger herbivores dwelling in the same areas.

The gorgonops is a member of the therapisid family - a group of reptiles that adapted well to change, were cold blooded and had a variety of mammalian characteristics. Their long legs tucked under the body and their oddly shaped teeth (odd for reptiles) gave way for the first mammals to evolve such as the thrinaxodon. Although the gorgonops seemed to be a wonder animal fully adapted for harsh weather it did not survive the great extinction 248 mya, mostly due to the fact that most of the animals they hunted became extinct.

First known herbivore reptile to evolve.

Name: Edaphosaurus (ed-eff-oh-saw-rus) “pavement lizard”
animal type: synapsid (pelycosaur) repitle
lived: 282-256 mya
size: 3 meters long
found: North America and Europe
fossil:

This animal looked a heck of a lot like the dimetrodon that I covered a while ago, but the two animals are distantly related and extremely different. The most obvious difference being that one was a ferocious meat eating predator while the edaphosaurus stuck to plants. Until this time all reptiles and amphibians had been carnivorous or insectivorous. Plants don’t hold nearly as much energy and proteins as the meats did - so animals would have to eat a lot more of them than they would meats to extract enough energy to life on.

Animals like the edaphosaurus  evolved different features in order to be able to properly tackle the plant life on earth. Their peg-like teeth could tear leaves apart like there was no tomorrow, and could break down twigs and branches with their powerful jaw. Even more teeth were found in the roof of the edaphosaurus’ mouth to further mash up the plant before it reached the stomach.

It’s large body allowed for a lot of food to be taken in at one time. It’s long gut would extract all the nutrients possible from its poor and limited diet of surrounding plants. The edaphosaurus would have liked swampy areas but could have survived in harsher desert climates. Its large sail, like on the dimetrodon, was used to regulate its temperature.

Just three more before dinosaur time!

A minion of the black ranger!

name:Dimetrodon (Die-met-roh-don) - two measure teeth
animal type: synapsid pelycosaur reptile
lived: 282 - 256 mya
size: 0.5 - 3.5 meters long
diet: carnivore
found: North America, Europe and Russia
fossil:

Often mistaken for a dinosaur the dimetrodon was a big reptile known for its mobility and the starting of the evolution for the world’s largest reptiles. It’s large sail on its back was the most obvious features on it. The large sail was used to regulate the reptiles body temperature. The reptile alright had a huge advantage over amphibians as the reptiles could hold moisture within their skin thus giving them an advantage in the arid climates. On top of that, the sail increased its body surface area by nearly 50% thus it would provide more skin for the sun to heat. The sail could turned toward the sun in the cooler mornings to gain more heat, regulating the temperature and raising its metabolism.

The dimetrodon would have hunted with its advanced smell and sight. It would hunt on land, sometimes in water, in swamps and even in the mountains. It would eat almost anything, including its own young. It was one of the first tetrapod to have teeth of differnet sizes therefore allowing it to catch a wide range of animals. It would eat efficiently with its strong jaw, and chewing allowed it’s food to be digested quickly.

Dimetrodon was a pelycosaur, a group of animals that may have looked like primitive dinosaurs but is more closely related to mammals.

Early croc and swamp signs.

name: proterogyrinus (pro-tuh-roe-gee-ree-nus) “early wanderer”
animal type: anthracosaur amphibian
size: 2.3 meters long
lived: Late Carboniferous 325 - 320 mya
diet: Carnivore
found: North America
fossil:

During the time period of the proterogyrinus, amphibians were an extremely diverse and exciting group of animals. They basically controlled the waterlogged forest areas and the proterogyrinus was one of the largest amphibians fully adapted for the life in the swamps. It could both hunt on land and in the water - it had powerful jaws and very sharp teeth that allowed to to hunt large animals both in and out of the water. It would have laid its eggs in water, but would have wandered into damp environments such as ponds and rivers to keep the eggs protected.

Most of the amphibians in the carboniferous period were really good swimmers and could move at great speeds through the waters but few actually made it onto the land. The proterogyrinus’ legs allowed it to catch food where its rivals couldn’t even dream of going. The biggest threats of the time were large water animals and sharks, thus its legs allowed it to seek refuge on shores and logs with ease where other amphibians couldn’t.

Proterogyrinus was an anthracosaur meaning that it belonged to a group of advanced amphibians known as reptilmorphs because it had reptilian characteristics. The amphibians that we have today would have evolved from the batrachomorphs who also lived in the carboniferous swamps. The largest amphibian on the fossil record was koolasuchus, by the start of the mezozoic era, 248 mya, the larger amphibian fossils were virtually unknown.