There once lived a dynamic group of animals called dinosaurs. Dinosaurs were around for nearly 150 million years and then, suddenly, they disappeared from the face of the Earth in the greatest unsolved mystery ever written.
Dinosaurs were reptiles, and like the reptiles of today, they had scaly skin and laid eggs. But reptiles today have short, sprawling legs. Dinosaurs had long legs tucked under their bodies. This allowed them to move with great efficiency.
Just as there are different types of reptiles today (snakes, turtles, alligators, lizards), there were other reptiles that lived at the same time as the dinosaurs. These were the familiar flying and swimming reptiles - pterosaurs, plesiosaurs, and ichthyosaurs. Dinosaurs lived only on land. They did not fly, and they did not swim in the seas.
We know about dinosaurs today because their bones, teeth, footprints, skin impressions, nests, and eggs have been found as fossils. These fossils are the clues that tell us what dinosaurs ate, how they protected and defended themselves how long they lived, their rate of growth, their behavior, and the environment in which they lived.
Our knowledge about dinosaurs changes
as new information is uncovered, old information is re-examined, and new
technology is developed. New discoveries about dinosaurs give us knowledge
about a group of animals gone for 65 million years. By asking questions,
looking for information, and finding answers, we learn more about ourselves
and the history of our planet Earth.
'Kinds of Dinosaurs' Page