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 ...

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 …

Nov 11, 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.

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 …

Scientists estimate over a thousand dinosaur species once roamed Earth. Learn which ones were the largest and the smallest, what dinosaurs ate and how they behaved, as well as surprising …

Mar 27, 2025 · The word “dinosaur” isn’t a catch-all term for just any scaly, prehistoric giant. “There’s kind of a misconception that any big extinct thing was a dinosaur,” Smith says. In fact, …

6 hours ago · There's a new dinosaur species on the block. An international team, including a biologist from Penn State Lehigh Valley, discovered that a 75-million-year-old fossil classified …

Oct 27, 2009 · Scientists first began studying dinosaurs during the 1820s, when they discovered the bones of a large land reptile they dubbed a Megalosaurus (“big lizard”) buried in the …

3 hours ago · Theropods once trekked along a “dinosaur freeway” that stretched across a shoreline in what is now Bolivia, according to a new study.

Dinosaurs were a specialized group of land reptiles that lived during the Mesozoic Era, also called the "Age of Dinosaurs". The Mesozoic was the period of time between 252 million and 66 …