Over 66 million years ago in a time known as a Mesozoic era the dinosaurs revolved before any human in the universe. It was like that for a while too, but something dangerous happened to the dinosaurs that we can only blame on the environment.
We can only blame the environment for this fault which is the reason we say the dinosaurs extinction was an environmental cause
The meteor was 7.5 miles wide an it hit where we know as Mexico. Smoke covered the atmosphere for a long time.