As the tundras expanded and contracted

pero también presentaba ciertas características craneales más similares a los terópodos más primitivos

Length 562 mm

and hunting by early humans in the Americas

Sphenacodon ferox featured only a low crest

Inostrancevia alexandri Scale:1:35 As the tundras expanded andInostrancevia alexandri, an extinct species of gorgonopsid therapsid that inhabited Earth during the Permian period, approximately 270 to 260 million years ago. It was a large predator that ranked high in the food chain of its ecosystem. This therapsid belonged to the group of gorgonopsids, a family of carnivores that were characterized by their developed fangs and their appearance similar to that of reptiles, although they were more closely related