Dinosaurs existed during the Mesozoic Era, first appearing around 230 million years ago and dying out about 65 million years ago. However, scientists largely agree that birds are the direct descendants of dinosaurs. If s... More »

The purported mass dinosaur die off known as the K-Pg extinction event took place during the end of the Cretaceous Period (K) during the Mesozoic Era some 65 million years ago. This scientific theory is based on the stud... More »

Historians believe that the city of Rome was founded in 625 BC, which means that the Romans lived more than two and a half thousand years ago. The final fall of Rome occurred in the year 1453 AD, which means that some Ro... More »

The purported mass dinosaur die off known as the K-Pg extinction event took place during the end of the Cretaceous Period (K) during the Mesozoic Era some 65 million years ago. This scientific theory is based on the stud... More »

The ankylosaurus became extinct with the other great dinosaurs during the Cretaceous-Paleogene extinction event that occurred about 66 million years ago. While some questions remain about what caused this extinction, geo... More »

The earliest conclusive evidence of the evolution of dinosaurs dates their origins to 230 million years ago. They are believed to have evolved from other reptilian species and developed certain defining characteristics, ... More »

Dinosaurs come from the evolution of early primitive organisms approximately 230 million years ago and it is unknown why these organisms evolved into dinosaurs. Scientists have been able to trace dinosaurs back 228 milli... More »