What are dinosaurs? Dinosaurs were cold-blooded reptiles. But that doesn't mean they have cold blood! That means their body temperature is the same as the temperature outside. Dinosaurs first evolved in the Triassic period. Next was the Jurassic period. The most well known dinosaurs like T-Rex and Triceratops were in the Cretaceous period.
65 million years ago they became extinct. There are many theories about how this happened. But the most common way was a asteroid came plummeting down to Earth at high speeds. Then with clouds of dust that blocked out the sun. Trees and other vegetation couldn't get sunlight and they died. Then the plant- eating dinosaurs that ate the plants and they would die too. Then the meat-eating dinosaurs would eat all the dead dinosaurs. They would then turn on each other. When nothing else was left to eat for the survives they would die too.
Dinosaurs had scaly skin that covered them. How do we know this? Because scientist called paleontologist dig up fossilized dinosaur skin if they are lucky. Paleontologist also dig up dinosaurs bones that we see in museums. People discovered 900 types of dinosaurs. Dinosaurs had to die by water to get fossilized. Because the mud and sand had to be mixed together so it could become rock like a protective suit to last over time.
