Good question. Richard F. is our dinosaur expert. He's got a pretty good answer for you.

We've answered some questions about dinosaurs before. There are lots of dinosaur books in your school library. Many of them answer the first part of your question. The second part of your question, about mixing up bones, is so interesting that we've decided to concentrate on it.

Sometimes fossil bones do get mixed up. For example, two skeletons could get mixed together if they were both swept downstream by a river. Sometimes it's easy to tell them apart. If you scrambled together the skeletons of a dog and a cow, it would be pretty easy to tell which ones belonged together, wouldn't it? The cow's bones are a lot bigger than the dog's. But if you mixed up a horse and a cow skeleton, you might have a very hard time telling them apart. You might have to find another horse's skeleton that wasn't mixed up. Then you could compare the mixed up bones with the horse's and take away the ones that were the same. The bones that were left behind would be cow's bones. Exactly the same sort of thing sometimes happens with dinosaur bones.

Sometimes it's the scientists who mix up the bones. Here's a famous example.The first brontosaur skeleton didn't have a skull. Maybe it had been washed away or crushed, or something. Anyway, scientists found another skull with neck bones that looked a lot like brontosaur neck bones. So they thought it was a brontosaur's skull and put them together in the museum. After many years, some more complete skeletons were found. Then scientists realized that the skull they had found was not a brontosaur's, but a camarasaur's instead. The brontosaur's skull looked quite different. So they fixed the skeletons in the museums.

By the way, the scientific name for brontosaur is apatosaurus, but most people call it brontosaur, and why not? The scientific name for horse is equus, but that doesn't stop us from calling them horses.

Richard's right, we checked your library and there's a great book called

The Rourke Dinosaur Dictionary by Joseph Hincks catalogue number 567.903 - hin

Take a look at it and find the names that Richard mentions. Thanks for your question.