DINOSAURS, EVOLVED?

Types of Dinosaurs

Dinosaurs are classified into two major groups. Harry Seeley, a British paleontologist, established the two suborders of dinosaurs in 1887, distinguishing them based on their hip structure. These two suborders include Saurischian dinosaurs, meaning "lizard-hipped", and Ornithischia, which means "bird-hipped". Over 1000 dinosaurs have been identified and named; however, there are many new and different species still to be discovered; therefore, there is not a specific number as dinosaurs are still being discovered. In fact, less than 10% of dinosaurs are said to be found currently.

 

Extinction

Dinosaurs were the most successful and the largest vertebrates on land, ruling the Earth during most of the Mesozoic Era(about 150 million years). Many theories have been proposed to explain the reason for their extinction.

 

About sixty-five million years ago, towards the end of the Cretaceous period, over half of the world's species were wiped out, including the dinosaurs. This major event is known as the Cretaceous-Tertiary or K-T mass extinction. There is no definite answer for the cause of this extinction. However, there are many theories and speculations, most centering around climate change.