Wow, Fossil Friday has a teeny tiny head.
Cotylorhynchus romeri, meaning “cup snout,” lived about 280 million years ago, and is a distant mammal relative. The fossil record indicates that it was a common large land animal in North America about 30 million years before the first dinosaurs.
Cotylorhynchus was the largest of the early relatives of mammals, measuring about 12 feet in length and, possibly, weighing over 800 pounds. Likely a plant-eater, its small head and broad body differed from the larger head and narrower body of Dimetrodon. Cotylorhynchus may, in fact, have been one of Dimetrodon’s favorite meals.
Find this fossil in the Museum’s Hall of Primitive Mammals.