570 vanished lives

18Paleozoic

This sail-backed predator was closer to mammals than to dinosaurs.

19Paleozoic

A beaked, tusked survivor became extraordinarily common after Earth’s greatest mass extinction.

38Paleozoic

Long saber canines armed one of the largest predators of the latest Permian.

84Paleozoic

A thick skull roof capped this heavy plant-eating mammal relative.

105Paleozoic

Crossbars projected from the spines of its tall sail above a broad plant-processing body.

138Paleozoic

Paired bony bosses formed a rough crown on the skull of this large, probably plant-eating therapsid.

169Paleozoic

A tiny head joined a barrel-shaped giant body whose broad ribs enclosed a vast plant-fermenting digestive system.

218Paleozoic

A beak, short tusks and powerful forelimbs made this one of the most common burrowing herbivores of the Late Permian.

219Paleozoic

Long upper canines and a wide gape made it an early experiment in saber-toothed predation.

261Paleozoic

Its long skull and deep tail suggest a waterside animal that was still a capable walker.

262Paleozoic

Low vertebral ridges accompanied a deep skull and strongly differentiated teeth.

263Paleozoic

A light build, long limbs and small skull bosses combine primitive and therapsid features.

264Paleozoic

A huge skull combined thickened impact surfaces with long canines in a formidable predator.

265Paleozoic

A domed, massively thick skull crowned the barrel body of this giant herbivore.