If you look closely at the name, you'll notice that Maiasaura ends with an "-a" rather than an "-us;" that's because this is one of the few dinosaurs named after the female gender.
The remains of more than 200 Maiasauras have been found at "Egg Mountain" in western Montana; their close proximity to their eggs (which were about the same size as modern ostrich eggs) means that a large proportion of them must have been female. Also, there's some evidence (based on fossil remains of juveniles) that adult Maiasauras cared for their kids after they hatched. We can thank the paleontologist Jack Horner, who discovered Egg Mountain, for most of the information we have about Maiasaura's behavior.
This parenting activity, combined with the fact that Maiasauras roamed the North American plains in large herds, makes these ancient hadrosaurs very similar, behaviorally, to modern herbivores like buffalo and bison.
