Grasslands at Egg Mountain area near Choteau, Montana. Egg Mountain with nests and eggs of the duck-billed dinosaur, Maiasaura peeblesorum.

- Image ID: P2N5C4
Grasslands at Egg Mountain area near Choteau, Montana. Egg Mountain with nests and eggs of the duck-billed dinosaur, Maiasaura peeblesorum.
Janice and Nolan Braud / Alamy Stock Photo
Image ID: P2N5C4
Grasslands at Egg Mountain area along US Highway 287 near Choteau, Montana. At Egg Mountain, nests and eggs of the duck-billed dinosaur, Maiasaura peeblesorum, (Montana State Fossil) and the small plant-eater Orodromeus makelai have been found. The 1978 discovery of fourteen dinosaur nests by Jack Horner helped convince other paleontologists that dinosaurs built vast colonies in order to better care for their young in a manner similar to birds. It is now widely believed that all dinosaurs reproduced by laying eggs.
Location: U.S. 287, near Choteau, MT, USA