Dec 22, 2025 · 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. Most died …

Dec 12, 2025 · Tyrannosaurus rex, species of large predatory theropod dinosaurs that lived during the end of the Cretaceous Period (about 66 million years ago) known from fossils found in the United …

This Encyclopedia Britannica Animals list features 8 titanosaurs, some of the biggest dinosaurs and biggest land animals that ever lived.

Theropod, any member of the dinosaur subgroup Theropoda, which includes all the flesh-eating dinosaurs. Theropods were the most diverse group of saurischian (“lizard-hipped”) dinosaurs, …

Archaeopteryx, genus of feathered dinosaur that was once thought to be the oldest known fossil bird. Its wing design and the structure and arrangement of its wing feathers were similar to that of most living …

Nov 8, 2025 · La tarde del dinosaurio (1976; “The Afternoon of the Dinosaur”) is a volume of stories with a prologue by Cortázar. Witty El museo de los esfuerzos inútiles (1983; The Museum of Useless …

Quetzalcoatlus is a genus made up of two species of giant pterosaurs, classified in the family Azhdarchidae, that lived during the Maastrichtian Age (72.1 million to 66 million years ago) of the …

Dec 4, 2025 · Titanoboa, (Titanoboa cerrejonensis), extinct snake that lived during the Paleocene Epoch (66 million to 56 million years ago), considered to be the largest known member of the suborder …

Take this Science quiz at Encyclopaedia Britannica to test your knowledge of dinosaurs.

Ornithischian, any member of the large taxonomic group of herbivorous dinosaurs comprising Triceratops and all dinosaurs more closely related to it than to birds. The ornithischians (meaning …