What is a dinosaur?
Dr. Richard Owen, a British physician, coined the name dinosaur in 1841. The word “Dinosaur” is a combination of the Greek words “deinos and “sauros and translates literally to mean “fearfully great lizard. Surprisingly, defining what is a dinosaur is a very difficult question. Very generally, the word dinosaur refers to a large group of reptiles that evolved during the Mesozoic era which stood erect and which generally had hind limbs longer than their front limbs. Scientists today use a long list of very specific criteria to determine if an animal should be classified as a dinosaur. Those criteria include such things as underslung legs that gave them an erect posture, bird-like or lizard-like hips with a large hole in the hip-socket, a secondary palate that permits them to eat and breathe at the same time, two pairs of holes in the temporal region of the skull, and many others. (return) How many types of dinosaurs were there? There were probably tens of thousands of species of dinosau
