Brat, a really big dinosaur comes to stay. The other dinosaurs found his differences annoying, but when trouble comes, they realized being different can be a blessing. (I call dinosaur giant lizards)Millions of years ago, long before there were any people, there were dinosaurs. Dinosaurs were one of several kinds of prehistoric reptiles that lived during the Mesozoic era, the "Age of Reptiles."They dominated the Earth for over 165 million years during the Mesozoic era, mysteriously they went extinct; paleontologists study their fossil remains to learn about the amazing prehistoric world of dinosaurs.