Taxonomy term

In a remote region of Western Australia, paleontologists have documented the world’s most diverse assemblage of dinosaur tracks. The scientists found preserved in Early Cretaceous rocks thousands of tracks, 150 of which can be assigned to at least 11, and possibly as many as 21, different known track types representing theropods, sauropods, ornithopods and armored thyreophorans.

Dinosaurs have long been grouped into two major clades — Ornithischia and Saurischia — largely based on the shapes of their hips. But new phylogenetic research is shaking up the dinosaur family tree, suggesting the traditional two-branch system needs reorganizing.

Newly described fossils from one of the earliest-known marsupials are shedding light on the evolution of mammals during the Mesozoic and revealing an animal with an impressive bite, perhaps strong enough to take down a dinosaur.

Paleontologists have discovered a new species of oviraptorosaur, a group of strange bird-like dinosaurs without teeth. The species, Tongtianlong limosus, has been described based on a specimen preserved in mudstone dating to the end of the Cretaceous. The find adds to a growing list of newly unearthed and similarly aged oviraptorosaur species, suggesting the group flourished during the last few million years of the Age of Dinosaurs before all nonavian dinosaurs were killed off in the end-Cretaceous mass extinction.