Maiasaura (meaning "good mother reptile" or "good mother lizard" ) is a large herbivorous hadrosaurid ("duck-billed") dinosaur genus that lived in the area currently covered by the state of Montana in the Upper Cretaceous Period (mid to late Campanian), about 76.7 million years ago. The first fossils of Maiasaura were discovered in 1978. The genus was named in 1979. The name refers to the find of nests with eggs, embryos and young animals, in a nesting colony. These showed that Maiasaura fed its young while they were in the nest, the first time such evidence was obtained for a dinosaur. Hundreds of bones of Maiasaura have been dug up. In this program, Buck and Blaze were both main protagonists and Maiasauras.