Dinosaurs lived for an enormously long time-some 150 million years – before they died out about
64 million years ago. All the dinosaurs disappeared at about the same time. However, whether
this happened over a few days, a few years, one or two centuries, or even a few thousand years is
impossible to say. Many people believe that the dinosaurs became extinct as a result of climate change
after a huge meteor or a small asteroid struck the Earth. The extinction of the dinosaurs was not an
isolated event. At the same time most marine reptiles and pterosaurs also died out.