Dinosaur - Wikipedia 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
DINOSAURIAN Definition Meaning - Merriam-Webster In this classification, all dinosaurs except birds became extinct at the end of the Cretaceous period approximately 65 million years ago, with all dinosaurs that are not birds referred to as dinosaurs or non-avian dinosaurs and birds typically referred to as avian dinosaurs The factory is now a rusting dinosaur
Dinosaur - Extinction, Fossils, Evolution | Britannica As a result, most dinosaur fossils are known from lowland environments, usually floodplains, deltas, lake beds, stream bottoms, and even some marine environments, where their bones apparently washed in after death
Dinosaurian - definition of dinosaurian by The Free Dictionary Define dinosaurian dinosaurian synonyms, dinosaurian pronunciation, dinosaurian translation, English dictionary definition of dinosaurian n 1 a Any of various extinct terrestrial reptiles of the orders Saurischia and Ornithischia that existed during the Mesozoic Era, including both
Physiology of dinosaurs - Wikipedia Recently, many new lines of evidence have been brought to bear on dinosaur physiology generally, including not only metabolic systems and thermoregulation, but on respiratory and cardiovascular systems as well
What Makes a Dinosaur a Dinosaur - U. S. National Park Service A more handy general definition would go something like this: Dinosaurs are extinct animals with upright limbs that lived on land during the Mesozoic Era (252 to 66 million years ago) This would basically capture how paleontologists long thought about dinosaurs