Genus
Valid Extinct

Maiasaura

Horner and Makela 1979
Etymology Reptile bonne mère.

Maiasaura is a large herbivorous saurolophine hadrosaurid ("duck-billed") dinosaur genus that lived in the area currently covered by the state of Montana and the Canadian province of Alberta, in the Upper Cretaceous, from 86.3 to 70.6 million years ago.

Temporal range
Triassic
Jurassic
Cretaceous
Paleogene
Neogene
252 201 145 66 0 Ma
PBDB occurrences
7
Group
Dinosaures
Herbivore Ground dwelling, gregarious Terrestrial
Maiasaura
click to enlarge
Maiasaura peeblesorum skeletal mount, Brussels Natural History museum (2009). © Meridas (Vladimír Socha) · CC BY-SA 4.0 · Wikimedia
PBDB ↗ Wikipedia ↗
Classification
Dinosauria Unranked clade
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Ornithischia Unranked clade
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Neornithischia Unranked clade
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Pyrodontia Unranked clade
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Cerapoda Unranked clade
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Ornithopoda Suborder
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Iguanodontia Infraorder
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Euiguanodontia Unranked clade
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Dryomorpha Unranked clade
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Ankylopollexia Unranked clade
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Styracosterna Unranked clade
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Hadrosauriformes Unranked clade
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Hadrosauroidea Unranked clade
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Hadrosauridae Family
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Hadrosaurinae Subfamily
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Brachylophosaurini Unranked clade
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Maiasaura Genus
Fossil sites 7 geolocated sites
Distribution
Top countries
🇺🇸 United States
7
Geological formations
Two Medicine
7
Temporal distribution
Campanian (83.6–72.2 Ma)
7
Species (1)
Maiasaura peeblesorum 84 Ma
News 2
New Study Suggests Juvenile Maiasaura Ate Different Food to Adults
tooth feeding fossil juvenile Hadrosauria +2
A newly published scientific paper has provided fresh insights into the feeding habits of the famous hadrosaur Maiasaura peeblesorum. Analysis of tooth wear in juvenile Maiasaura compared to adult hadrosaurs suggests that young Maiasaura fed differently from fully grown animals. Researchers examined dental wear associated with Maiasaura peeblesorum fossil teeth.  Dietary insights may help to
13/05/2026 everythingdinosaur
Dinosaurs May Have Fed Their Young a Special Diet, Study Suggests
Dinosaurs May Have Fed Their Young a Special Diet, Study Suggests
tooth juvenile Dinosauria Hadrosauria Maiasaura +1
An analysis of wear on the fossilized teeth of the hadrosaurian dinosaur Maiasaura peeblesorum indicates their juveniles may have eaten softer, more nutritious food than adults, hinting at advanced parental care among dinosaurs. The post Dinosaurs May Have Fed Their Young a Special Diet, Study Suggests appeared first on Sci.News: Breaking Science News.
11/05/2026 sci-news
Images 1
Bibliography
Original description
J. R. Horner and R. Makela. 1979. Nest of juveniles provides evidence of family structure among dinosaurs. Nature 282:296-298 DOI ↗
Bibliography (6)
R. R. Rogers, J. R. Horner, and J. Ramezani, E. M. Roberts, D. J. Varricchio. 2024. Updating the Upper Cretaceous (Campanian) Two Medicine Formation of Montana: lithostratigraphic revisions, new CA-ID-TIMS U-Pb ages, and a calibrated framework for dinosaur occurrences. GSA Bulletin DOI ↗
J. G. Schmitt, F. D. Jackson, and R. R. Hanna. 2014. Debris flow origin of an unusual Late Cretaceous hadrosaur bonebed in the Two Medicine Formation of western Montana. Hadrosaurs
D. A. Burnham, K. L. Derstler, and P. J. Currie, R. T. Bakker, Z. Zhou, J. H. Ostrom. 2000. Remarkable new birdlike dinosaur (Theropoda: Maniraptora) from the Upper Cretaceous of Montana. University of Kansas Paleontological Contributions 13:1-14
D. J. Varricchio. 1993. Taphonomy of Jack's Birthday site, a diverse dinosaur bone bed. Journal of Vertebrate Paleontology 13(3, suppl.):61A
K. F. Hirsch and B. Quinn. 1990. Eggs and eggshell fragments from the Upper Cretaceous Two Medicine Formation of Montana. Journal of Vertebrate Paleontology 10(4):491-511 DOI ↗
J. R. Horner and R. Makela. 1979. Nest of juveniles provides evidence of family structure among dinosaurs. Nature 282:296-298 DOI ↗