Brachiosaurus

Brachiosaurus was a huge dinosaur that lived a very long time ago. It lived in North America about 155 million years ago. A scientist named Elmer Riggs found its bones in Colorado. He named it Brachiosaurus, which means "arm lizard" in an old language.

Brachiosaurus was as long as six school buses parked end to end. It weighed as much as 30 elephants put together. Its neck was very, very long and stretched high up. Its head was small compared to its giant body. Its front legs were longer than its back legs, which made its body lean forward.

Brachiosaurus had a family of dinosaurs like it called Brachiosaurids. Scientists found similar dinosaurs in Africa and Europe too. One dinosaur from Africa was thought to be Brachiosaurus but was actually different. It got its own name, Giraffatitan, in 2009.

This dinosaur used its long neck to eat leaves high in the trees. It could reach food as high as a three-story building. Unlike other long-necked dinosaurs, it could not stand up on just its back legs. Scientists think Brachiosaurus kept itself warm like modern animals do. It is one of the most famous dinosaurs ever and appeared in the movie Jurassic Park.