Birds are avian dinosaurs, and phylogenetic taxonomy includes over 11,000 extant species in the group Dinosauria. Dinosaurs are a diverse group of reptiles [note 1] of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is a subject of active research. They ...
Over a thousand dinosaur species once roamed the Earth. Learn which ones were the largest and the smallest, what dinosaurs ate and how they behaved, as well as surprising facts about their ...
Dinosaur, the common name given to a group of reptiles, often very large, that first appeared roughly 245 million years ago and thrived worldwide for nearly 180 million years.
Delve into these fast facts about dinosaurs for kids of all ages. Discover why the Tyrannosaurus had sharp teeth, where the name “dinosaur” comes from, and more! Dinosaurs are a group of reptiles that have lived on Earth for about 245 million years.