Non-bird dinosaurs lived between about 245 and 66 million years ago, in a time known as the Mesozoic Era. This was many millions of years before the first modern humans, Homo sapiens, appeared. Scientists divide the Mesozoic Era into three periods: the Triassic, Jurassic and Cretaceous.
When did dinosaurs first live on Earth?
Dinosaurs were a successful group of animals that emerged between 240 million and 230 million years ago and came to rule the world until about 66 million years ago, when a giant asteroid slammed into Earth.
When did dinosaurs go extinct?
Dinosaurs went extinct about 65 million years ago (at the end of the Cretaceous Period), after living on Earth for about 165 million years.