#protomammals

[ildarotyrannus]

Portrait of the anomodont Anomocephalus africanus from the Middle Permian of South Africa. This therapsid is known from a deformed partial skull and jaw discovered in the Karoo Basin, famous for its diverse Permian faunas. The skull is approximately 20 cm long, with a moderately elongated snout. The zygomatic arch is typical of anomodonts. The lower jaw is fairly high. A complete set of teeth is present, with oval-shaped upper "incisors." The canines are barely stand out. Six teeth and four empty alveoli on the palate are preserved. The closest relative of Anomocephalus was the Brazilian Tiarajudens, an unusual fanged form known from a skull and partial postcranial skeleton. The African taxon may have had similar limb proportions (the proportions of the entire skeleton are not precisely known for either genera). Anomocephalus may have been a herbivore, crushing food with the chewing surfaces of its teeth.

Adobe Photoshop, 2026.

[typhlonectes]

Other Mammals, Not Dinosaurs, Kept Our Ancestors Down

The asteroid impact that ended the Cretaceous gave our mammalian ancestors, the therians, an edge over their mammalian competitors.

Dinosaurs so thoroughly dominated the ancient world that they suppressed the evolutionary possibilities open for mammals. This notion has been around for decades now, and it seems to be backed up by the fact that no known mammal became larger than badger-sized during the time dinosaurs were the most prominent animals on land. But, thanks to decades of new fossil discoveries, paleontologists have realized an important twist in the story—it wasn’t dinosaurs that suppressed the evolution of our ancient mammalian ancestors, but other forms of ancient mammal.

Paleontologists who study fossil mammals have suspected the story of “dinosaur dominance” was too simple, but, until now, the critical evidence was missing. Clues that the picture was more complicated now come from a new Current Biology paper by University of Oxford paleontologist Elsa Panciroli and colleagues that followed the evolutionary spread of various mammals during the Age of Dinosaurs—from more ancient types called mammaliaforms to the group of mammals found all around us today, the therians. 

Because the ancient mammaliaforms diversified and spread into so many forms first, the researchers found, our own mammalian ancestors and relatives didn’t have a chance to truly dig their claws into the world’s ecosystems until after the asteroid strike that sparked a mass extinction 66 million years ago...

Read more: https://www.smithsonianmag.com/science-nature/other-mammals-not-dinosaurs-kept-our-ancestors-down-180978040/

[typhlonectes]

The Traits That Spawned the Age of Mammals

Lots of the traits we think of as defining us as mammals show up pretty early, during the time of the dinosaurs.  And, in some cases, they show up a lot earlier and in things that weren’t mammals at all. 

Big thanks to Julio Lacerda (https://twitter.com/JulioTheArtist​) for the excellent Morganucodon and Microdocodon illustrations! 

Produced by Complexly for PBS Digital Studios

via: PBS Eons

[immoren]

[palaeomedia-reviews]

I didn’t get a very good shot of the Dicynodon sculptures at Crystal Palace Park, so here’s one I found by Ben Sutherland

Dicynodon was a... well, a dicynodont: a specific group of protomammalian synapsids (otherwise known as the coolest animals, but don't tell the other mods!) that has sharp beaks and two long, protruding canines. Hence the name dicynodont or 'two dog-like teeth'. These two Dicynodon look like turtles! Nothing like the real animal. If you asked me to identity it without clues, I couldn't tell you what it was supposed to be! A real Dicynodon was a burrowing animal with a short tail, sprawling legs with clawed digits, a boxy head with a sharp beak and teeth. It could've had fur like modern mammals, but that remains to be seen until appropriate fossil evidence has been found.