Synapsid Stickers
Description: Dimetrodon was part of a group known as known as mammal-like reptiles or stem-mammals. While they share many traits with modern reptiles and modern mammals they are neither, but are part of the overall group called Synapsids that includes all modern mammals (even humans like you). While it is often associated with dinosaurs in popular media these sail-backed quadripeds are much older than that group and are most closely related to us than they are to dinosaurs. Dimetrodon main defining traits include a very distinctive sail supported by extensive neural spins, as well as a set of differentiating teeth that were clearly evolved to different uses, something we and most modern mammals share.
Description: Roughly 259.8 to 254.1 million years ago during the Late Permian era in what would eventually become South Africa, deserts sands blew across an arid landscape. Meanwhile, to escape the oppressive heat and avoid predation a tiny synapsid called Diictodon (the name meaning “two weasel toothed”) used it’s stubby legs, sharp claws, and peculiar tusks to dig into their earth, constructing relatively large (for their size) corkscrew-shaped burrows, designed to protect and give them an easy route up and down.
Description: During the Late Permian period (around 260 to 254 million years ago) Inostracevia and the rest of it’s family group, Gorgonopsidae were some of the largest predators on the planet, they roamed what is now Northern Russia, stalking their prey with a smiled full of sabers. Gorgonopsids were part of a group called therapsids, a group of animals that include mammals and their ancestors. They were a group that also shared common traits with reptiles but weren’t quite part of either modern group.
Description: Dimetrodon was a pelycosaur, one of the earliest types of synapsids — a group that includes all mammals. That makes Dimetrodon an early relative in the evolutionary line that eventually led to mammals, including humans. Synapsids are defined by a specific skull feature: a single opening behind each eye socket, known as a temporal fenestra. This sets them apart from other major vertebrate groups like diapsids (which have two openings), a group that includes reptiles and birds. So, even though Dimetrodon looked reptilian and lived long before the first dinosaurs, it’s actually more closely related to mammals.
Description: Estemmenosuchus mirabilis was a genus of therapsid that lived during the Middle Permian (267 million years ago). Found in what is now the Perm region of Russia in the 1960s, both of the currently recognized species: E. uralensis and E. mirabilis are most recognizable from their distinctive knobby, antler-like facial structures; these structures are in face where they get their name which means "crowned crocodile."
