The earliest known description of dinosaur bonesis from China in 3000 BCE. Chinese apothecaries thought dinosaur bones thatwere to be the bones of dragons. In 1842, Richard Owen coined the word “dinosaur”which meant “terrible lizard”. Upuntil the 1960s, dinosaurs were generally treated as sluggish, stupid creatures.In 1964, the pivotal fossil discovery was the original sickle-clawed “raptor”theropod, Deinonychus.
It was discovered by Yale paleontologist John Ostrom. Heargued that some dinosaurs were truly more active than previous assumptions. Furthermore,John Ostrom also noted many bird-like features on the skeleton of Deinonychusand other theropod dinosaurs. It gave people the brand new idea that birdsevolved from a group of dinosaurs. Thus, this idea leads to a tendency to thinkdinosaurs were more bird-like than lizard-like, such as looking after theirinfants and traveling in flocks.
Dinosaurs were the mostpopular organisms during the Mesozoic Era (225-65million years ago). Dinosaurs existed for about 150 million years, and they dominatedevery type of environment on Earth. They were land-dwelling vertebrates, andmembers of the group Archosauria, a group of animals that also includespterosaurs (flying reptiles) and crocodiles. Dinosaurs can be classified bytheir mode of eating.
The Herbivore dinosaurs eatplants, the carnivore dinosaurs eat meat, and the omnivore dinosaurs eat bothplants and meat.The size range of Dinosaursare very broad. Little dinosaurs can be as small as 3 feet and weigh nearly 4 pounds, such as Compsognathus (small, bipedal, and carnivorousdinosaurs). Big dinosaurs can be as large as over 100 feet long, and weigh upto 150 tons, such as Brachiosaurus (long neck, small head, huge size, and herbivoredinosaurs). According to their hipbones, dinosaurs are divided into two major groups. The first major group isSaurischia (lizard-hipped dinosaurs). Saurischia can be further subdivided intotwo smaller groups, the theropods (bipedal carnivorous dinosaurs), and thesauropods (large, four-legged, herbivorous dinosaurs).
The second major groupis Ornithischia (bird-hipped dinosaurus). Ornithischia can be furthersubdivided into five smaller groups, the Ornithopoda (duck-billed dinosaurs),the Stegosauria (plated dinosaurs), the Ankylosauria (armored dinosaurs), thePachycephalosauria (dome-headed dinosaurs), and the Ceratopsia (horneddinosaurs). Dinosaurswere living on earth during the Mesozoic Era, and itwas the “Age of Dinosaurs”.
The word of Mesozoic means “middle life.”The Mesozoic Era can be divided into three major periods: theTriassic (248-206 million years ago), the Jurassic (206-144 million years ago),and the Cretaceous (144-65 million years ago). First, dinosaurs appeared and evolvedin the Triassic period. Second, dinosaurs became diverse in the Jurassic period.
Last, dinosaurs became extinct at the end of the Cretaceous period. Each periodhad various well-known forms. For example, the Triassic period had Eoraptor, Lessemsaurus,and Pterosaurs. The Jurassic period had Allosaurus, Stegosaurus, andApatosaurus. The Cretaceous period had Tyrannosaurus, Velociraptor,Triceratops, and Pachycephalosaurus. Inconclusion, dinosaurs are the most celebrated fossil organisms in the world.These remarkably diverse and successful animals inhabited every majorcontinent, persisted over 150 million years, and evolved numerous bizarre formsof varying body sizes.