Dinosaurs lived between 230 and 65 million years ago, in a time known as the Mesozoic Era. This was many millions of years before the first modern humans, Homo sapiens, appeared. Scientists divide the Mesozoic Era into three periods: the Triassic, Jurassic and Cretaceous.
The last dinosaurs died approximately 65 million years ago. Although the cause of their extinction is still a mystery, climatic change, diseases, changing plant communities, and geologic events could all have played a role. Lately, dinosaur extinction theories have been the subject of much debate and controversy.
The Cretaceous–Paleogene (K–Pg) extinction event, also known as the Cretaceous–Tertiary (K–T) extinction, was a mass extinction of some three-quarters of the plant and animal species on Earth that occurred over a geologically short period of time, approximately 66 million years ago.
Scientists strap fake dinosaur tail on chickens to discover how T-Rex walked [Video] With scientists having named the chicken as the closest living relative of the mighty T-Rex, a second group of researchers have decided to put the findings into practice - by strapping a fake dinosaur tail to the birds.Feb 9, 2014