Old Earth Ministries Online Dinosaur Curriculum
Free online curriculum for homeschools and private schools
From Old Earth Ministries (We Believe in an Old Earth...and God!)
NOTE: If you found this page through a search engine, please visit the intro page first.
Lesson 60 - Maiasaura
Maiasaura (from the Greek meaning "caring mother lizard") is a large duck-billed dinosaur
genus that lived in the area currently covered by the state of Montana in
the Late Cretaceous Period (Campanian), about 74 million years ago.
Maiasaura was large, attaining an adult length of about 9 metres (30 ft) and had the typical hadrosaurid flat beak and a thick nose. It had a small, spiky crest in front of its eyes. The crest may have been used in headbutting contests between males during the breeding season.
Maiasaura was herbivorous. It walked both on two (bipedal) or four (quadrupedal) legs and appeared to have no defense against predators, except, perhaps, its heavy muscular tail and its herd behaviour. These herds were extremely large and could have comprised as many as 10,000 individuals. Maisaura lived in an inland habitat.
Length: 30 feet
Date Range: 74 Ma, Campanian Age, Cretaceous Period
|Adult skeleton at the Museum voor Natuurwetenschappen in Brussels, Belgium (Picture Source)|
Maiasaura was discovered by Laurie Trexler and described by dinosaur paleontologist Jack Horner (paleontologic advisor for the Jurassic Park movies) and Robert Makela. He named the dinosaur after Marion Brandvold's discovery of a nest with remains of eggshells and babies too large to be hatchlings. These discoveries led to others, and the area became known as "Egg Mountain", in rocks of the Two Medicine Formation near Choteau in western Montana. This was the first proof of giant dinosaurs raising and feeding their young. Over 200 specimens, in all age ranges, have been found. The announcement of Maiasaura's discovery attracted renewed scientific interest to the Two Medicine Formation and many other new kinds of dinosaurs were discovered as a result of the increased attention. Choteau Maiasaura remains are found in higher strata than their Two Medicine River counterparts.
Maiasaura lived in herds and it raised its young in nesting colonies. The nests in the
The eggs were incubated by the heat resulting from rotting vegetation placed into the nest by the parents, rather than a parent sitting on the nest. Upon hatching, fossils of baby Maiasaura show that their legs were not fully developed and thus they were incapable of walking. Fossils also show that their teeth were partly worn, which means that the adults brought food to the nest.
The hatchlings grew from a size of 16 to 58 inches (41 to 150 cm) long in the span of their first year. At this point, or perhaps after another year, the animal left the nest. This high rate of growth may be evidence of warm bloodedness. The hatchlings had different facial proportions from the adults, with larger eyes and a shorter snout.
In the Two Medicine Formation, Maiasaura lived alongside many other dinosaurs,
Return to the Old Earth Ministries Online Dinosaur Curriculum homepage.
Bay State Replicas - Full skeleton (juvenile), skull (juvenile)