Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Superorder: Dinosauria
Order: Ornithischia
Suborder: Ornithopoda
Family: Hadrosauridae
Subfamily: Hadrosaurinae
Tribe: Maiasaurini
Genus: Maiasaura

Maiasaura was a medium-sized (7m long) hadrosaurid that lived during the late Cretaceous about 75 million years ago. The discovery of the animal in a nesting colony provided the first substantial evidence that dinosaurs cared for their young after hatching. Specimens have been found of nearly all ages, from embryo to adult, and provide an unusually rich stratum across the developmental history of these dinosaurs. Maiasaura had a fairly typical ornithopod body plan, with herbivorous adaptations and the ability to use both bipedal and quadrupedal locomotion. Unlike other hadrosaurids, the head had no significant crests or projections to distinguish it from other similar species.

Type Species: Maiasaura peeblesorum

Horner, JR; and Makela, R. (1979). Nest of juveniles provides evidence of family structure among dinosaurs. Nature, Vol. 282, pp. 296-298.

Locality:

Two Medicine Formation, Montana, USA.

Scientific Resources:

Chin, K. (2007). The Paleobiological Implications of Herbivorous Dinosaur Coprolites from the Upper Cretaceous Two Medicine Formation of Montana: Why Eat Wood? Palaios, Vol. 22, Issue 5, pp. 554-566.

Adams, JS; and Organ, CL. (2005). Histologic Determination of Ontogenetic Patterns and Processes in Hadrosaurain Ossified Tendons. Journal of Vertebrate Paleontology, Vol. 25, Issue 3, pp. 614-622.

Horner, JR; Ricqules, AD; and Padian, K. (2000). Long Bone Histology of the Hadrosaurid Dinosaur Maiasaura peeblesorum: Growth Dynamics and Physiology Based on an Ontogenetic Series of Skeletal Elements. Journal of Vertebrate Paleontology, Vol. 20, Issue 1, pp. 115-129.

Carpenter, K; Hirsch, KF; and Horner, JR. (1994). Dinosaur Eggs and Babies. Cambridge University Press.