Dinosaurs first appeared about 245 million years ago during the Triassic Period of the Mesozoic Era and lived until their extinction about 66 million years ago at the end of the Cretaceous Period
. This means dinosaurs roamed the Earth for roughly 179 million years before going extinct around 66 million years ago
. To summarize:
- Dinosaurs emerged approximately 245 million years ago.
- They became extinct about 66 million years ago.
- Their reign lasted nearly 180 million years during the Mesozoic Era, which includes the Triassic, Jurassic, and Cretaceous periods
Non-avian dinosaurs disappeared in the mass extinction event at the end of the Cretaceous, but avian dinosaurs (birds) are their living descendants
