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How Dinosaurs Work

Dinosaur Summary

Dinosaurs are land-based animals which lived from 230 million to 60 million years ago. Scientists study dinosaurs by looking at bone and egg fossils, footprint track ways, and by using our knowledge of dinosaurs' living relatives. Some dinosaurs were as small as modern birds, while others weighed many tons. Scientists have been able to put together entire dinosaur skeletons, but they still don't know what color their skin was or whether or not they had feathers.

Another question surrounding dinosaurs is whether or not they were warm-blooded, like birds, or cold-blooded, like reptiles. The discovery of some new fossils and more research could help shed light on this question. Like birds and reptiles, dinosaurs laid eggs. Matching a fossilized egg to a species is a difficult task, but scientists can learn about a dinosaur's behavior by examining an intact nest.

A popular theory for the extinction of dinosaurs, the Alvarez theory, states that an asteroid may have hit the Earth, causing the mass extinctions. Modern-day birds are the closest living relatives to dinosaurs, and scientists have recently discovered some "missing link" fossils that bolster this theory. Far from dying out, it seems the dinosaurs have simply evolved.

Top 5 Dinosaur Facts

  1. Many dinosaur bones have quill barbs - bumps showing that the dinosaurs, such as the Velociraptor, had feathers.

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  1. A dinosaur fossil was found in South Dakota that included all of the dinosaur's soft tissue and skin - just like a mummy!

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  1. Some dinosaurs lived at a time when the continents were connected in one great mass called Pangea.

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  1. The giant carnivore T-Rex was probably a scavenger rather than a hunter.

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  1. Many of the most well-known prehistoric reptiles, like the Pterodactyl, aren't dinosaurs since a dinosaur must technically be a four-legged land animal.

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