Maiasaura (meaning "Caring Mother Lizard") is a genus of hadrosaurid iguanodont from Late Cretaceous Montana. An adult could grow to about 30 feet long, about the same length of other large iguanodonts. Maiasaura had a small pointy crest above it's eyes, which scientists think it was used for males to head butt during breeding season. Like other iguanodonts, Maiasaura could be bipedal or quadrapedal. Maiasaura herds could have up to 10,000 individuals. Maiasaura was discovered by Laurie Trexler, but it was described by Jack Horner and Robert Makela.