.21" Partial Hadrosaur (Maiasaura) Tooth in Rock - Montana

Maiasaura, meaning "good mother reptile" or "good mother lizard", is a large herbivorous hadrosaur ("duck-billed") dinosaur that lived in what is now Montana in the Upper Cretaceous Period, about 76 million years ago. The first Maiasaura fossils were discovered in 1978. The name refers to the find of nests with eggs, embryos, and young animals in a nesting colony. This find revealed that Maiasaura fed its young while they were in the nest, the first time such evidence was obtained for a dinosaur. Maiasaura reached lengths of around 30 feet long, making it a fairly large Hadrosaur. Young animals walked on their hind legs, while adults walked on all fours.