What species of dinosaur was the smartest?

While those Velociraptors in the movie Jurassic Park were terribly smart, paleontologists think the Troodon had them beat in the brains department. This is because Troodons had the largest brain of any dinosaur in relation to its body size.

The Troodon was bird like dinosaur from the Cretaceous period (74-65 million years ago). It could grow as tall as an adult human (6 feet or 1.8 meters). By studying fossils of its skull scientist have concluded it was probably as smart as a modern ostrich. The skull also tells us that they probably had excellent vision.