Eoraptor lived about 230 million years ago. It is one of the oldest dinosaurs that have ever been found. Eoraptor was a carnivore, meaning that it ate meat. It probably ate lizards and maybe even fish and worms. It was probably also a scavenger, meaning that it ate animals that were already dead. It would also eat the leftovers from another dinosaur’s meal. The name “Eoraptor” means "dawn thief".
This dinosaur could be one of the most primitive ever, meaning that it was very simple. It was small – about three feet long – which is about the size of a large dog. It had a long snout and lots of small, sharp teeth. Like many smaller dinosaurs, Eoraptor had hollow bones. This made it very light and agile. This means that it could turn and run quickly. Eoraptor ran on its back legs but could also walk on all fours. Animals that can move on two legs are called bipedal. We know from its footprints that it was a fairly fast runner.
Eoraptor had five fingers on its hands like we do, so it could grab small creatures easily. But one of the fingers was so small that it you probably couldn’t even see it. The first bones of an Eoraptor were found in South America, in what is now the country of Argentina. The bones were found by accident. One member of a team of paleontologists was about to throw a small rock away when he noticed that the rock had teeth. When the team looked more closely, they noticed that there was an entire skull inside the rock. They were originally looking for another kind of dinosaur, a Herrerasaurus. They were surprised to have discovered a completely new species!