1. Maiasaurs were herbivorous. They weighed roughly 3–4 tons as adults. They probably ate 200 lb. of food each day.

8. The egg shells found in the nests of the Maiasaurs are all broken up.

2. Many Maiasaur nests have been found at two sites, Egg Mountain and Egg Island. At the time of the dinosaurs, each of these sites was an island. Although islands are limited in space, the nests were usually found 20–30 feet apart.


9. The front teeth of many dinosaurs like Maiasaurs are very interesting. There is a heavy enamel layer on the outside of the upper teeth, but that very same layer is on the inside of the lower teeth. Therefore, as the teeth come together. a self-sharpening effect takes place. The teeth become like scissors.

3. The sharp serrated teeth of a small dinosaur called Troödon have been found in the nesting area of Maiasaurs.


10. The shells found in nests of Orodromeus are not all broken up. The lower egg shell is usually intact.

4. Large numbers of bones in some areas of Montana indicate that there existed a herd of Maiasaurs of nearly 10,000 individuals. These individuals varied in size from 9 to 25 feet in length.


11. The bones of the hatchlings of Maiasaurs are not fully ossified. The ends are still relatively soft and spongy and cartilaginous.

5. The dinosaur nests at both of the Egg Mountain locations have been found at three different depths. Several layers of sandstone were deposited between the depths.


12. Examination of the embryos of Maiasaurs show wear on the front teeth. This has occurred before hatching.

6. The bones of most newborn birds are not fully ossified (hardened into bone). The ends are still relatively soft and spongy and made of cartilage. As a result, newborn birds can stand up only momentarily. Their bones will not support them.


13. At birth, Maiasaurs are about 20 inches in length. Bones have been found in the nests of Maiasaurs that belonged to individuals that were over 4 feet in length. This is very common.

7. The adult Maiasaur reached a size of 25–30 feet in length.


14. The bones of the hatchlings of Orodromeus are fully ossified. That means that the ends of the bones are well developed and very strong.