English: Maiasaura is a large hadrosaur known from huge bone beds containing as many as 200 individuals, allowing paleontologists to understand how it lived and grew. Maiasaura lived in large herds and raised their young in nesting colonies, with each nest containing 30 to 40 eggs. Upon hatching, baby Maiasaura legs were not developed, and adults brought food to the nest to feed them. When the young left the nest, they walked mainly bipedally, switching to a quadrupedal stance as they grew larger. Adult Maiasaura grew to about 9 m in length with a body mass up to 4 t. They had a prominent short, solid crest-like structure between the eyes.