What observations did scientists make about dinosaurs that made them think dinosuars were not lizards?

dinosaurs shared many features with todays lizards. they had skeletons with backbones. they had scales. many walked on four legs. but there differences between the two groups of animals. dinosaurs legs go almost straight down from their bodies. legs of todays lizards stick out more from the sides of the bodies. some dinosaurs share many features with birds. for instance, some dinosaurs had features and a wishbone! also, a few fossils have included more than just bones. these fossils have shown that some dinosaurs had a heart that is similar to a birds or a mammals heart.

NOTE: ( i got this info from my science book )