Dinosaurs were a varied group of animals. Paleontologists have identified over 500 distinct
genera[2] and more than 1,000 different species of dinosaur, and remains have been found on every continent on Earth. Some dinosaurs were herbivorous, others carnivorous. Some were
bipedal, others
quadrupedal, and others were able to shift between these body postures. Many species developed elaborate skeletal modifications such as
bony armor, horns or crests. Although generally known for their large size, many dinosaurs were human-sized or even smaller. Most major groups of dinosaurs are known to have built nests and laid eggs, suggesting an
oviparity similar to that of modern birds.
The term "dinosaur" was coined in 1842 by
Sir Richard Owen and derives from
Greek δεινός (deinos) "terrible, powerful, wondrous" + σαῦρος (sauros) "lizard". Through the first half of the twentieth century, most of the scientific community believed dinosaurs to have been sluggish, unintelligent
cold-blooded animals. Most
research conducted since the 1970s, however, has indicated that dinosaurs were active animals with elevated
metabolisms and numerous adaptations for social interaction.
Since the first dinosaur
fossils were recognized in the early
nineteenth century, mounted dinosaur skeletons have been major attractions at museums around the world, and dinosaurs have become a part of world culture. They have been featured in best-selling books and films such as
Jurassic Park, and new discoveries are regularly covered by the
media. As a result, the word "dinosaur" has entered the
vernacular, although its use and meaning in colloquial speech may be inconsistent with modern science. In English, for example, "dinosaur" is commonly used to describe anything that is impractically large, slow-moving, obsolete, or bound for extinction.
