Dinosaurs lived during the Mesozoic era, between 250 and 65 million years ago. The earliest discovered dinosaur species, Nyasasaurus parringtoni, dates from 245 million years ago. Dinosaur fossils are most common between... More »

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Dinosaurs existed during the Mesozoic Era, first appearing around 230 million years ago and dying out about 65 million years ago. However, scientists largely agree that birds are the direct descendants of dinosaurs. If s... More »

Dinosaurs lived on Earth for about 175 million years, until they were entirely wiped out by the K-T extinction event at the end of the Cretaceous Period. They lived during the Mesozoic Era, and examples of dinosaurs can ... More »

The earliest conclusive evidence of the evolution of dinosaurs dates their origins to 230 million years ago. They are believed to have evolved from other reptilian species and developed certain defining characteristics, ... More »

The ankylosaurus became extinct with the other great dinosaurs during the Cretaceous-Paleogene extinction event that occurred about 66 million years ago. While some questions remain about what caused this extinction, geo... More »

Dinosaurs come from the evolution of early primitive organisms approximately 230 million years ago and it is unknown why these organisms evolved into dinosaurs. Scientists have been able to trace dinosaurs back 228 milli... More »

Tyrannosaurus rex dinosaurs lived during the late Cretaceous period, which was about 65 million years ago, on a continent named Laramidia. Laramidia is now part of North America. The name Tyrannosaurus rex means "tyrant ... More »

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