Introduction to Maiasaura Dinosaur
Maiasaura, a genus of Late Cretaceous (Campanian) hadrosaurs, is one of the most well-studied species of dinosaurs from the North American fossil record. Of the many species of hadrosaur that have been discovered, Maiasaura stands out as one of the most well-preserved specimens and is a key to our understanding of life in the Late Cretaceous period. The name of Maiasaura roughly translates as “good mother lizard” and reflects the maternal care of the species illustrated by its nesting sites and young. Despite having a relatively small body, the discovery of Maiasaura has shed light on several aspects of the Late Cretaceous, including the environment at the time, social structures among dinosaurs, and the survivorship rates of the species.
Origin and Discovery
Maiasaura was first discovered in 1978 by paleontologist Jack Horner at the Egg Mountain site in Montana, USA. It is part of the family of hadrosaurs known as Lambeosaurines. These creatures had teeth suited for grazing on plants, not carnivorous predation. Maiasaura wasn’t the first hadrosaur discovered, but remained for several years the most complete and best-preserved genus. The origin of Maiasaura’s species is yet to be determined, however, the Lambeosaurines have a suspected origin in Asia.
Physical Attributes
Maiasaura was a large bipedal dinosaur with a length of approximately 9m (30ft) and a weight of approximately 3.5 tonnes. The skull had a long snout with blunt teeth and a powerful jaw capable of copping tough plants. Its body was covered with bird-like feathers, providing an insulating layer against the cool Montana climate. It bore a long and thick tail which was used for balance and fine tuning of movement. Its feet were broad and flattened with narrow toes and claws, which were well adapted to the soft mud and marshy conditions.
Nesting and Mating
Maiasaura is well-known for its nesting behaviours. It was the first dinosaur species to be associated with the practice of parental care, with various specimens of fossilised hatchlings and eggs indicating that the species sheltered and cared for their young. Maiasaura was an herbivorous dinosaur and would have lived in herds. It is thought that Maiasaura had an extended reproductive cycle, with mating periods during the spring and eggs being laid during the summer and autumn.
Social Structure
Maiasaura was a fairly social species, with a clear hierarchical structure present in the herds. It is thought that a dominant, older female would lead the herd and act as a caretaker for the younger animals. Studies of the fossil record indicate that very few adults were killed while they were caring for the eggs or hatchlings, suggesting that the adults were in a position of authority and the young were given precedence over possible predation. This is unique in the fossil record and is further evidence that Maiasaura was a highly social species.
Environment and Diet
The Maiasaura lived in a relatively cool environment of temperate open grasslands. Fossils found at the Egg Mountain site indicate that the climate was fairly dry during the Cretaceous, leading to the species being adapted to a wide range of plant material from grass to dried leaves, conifer needles, fruits and nuts. Analysis of the fossilised tooth marks indicates that the Maiasaura used a combination of grazing and browsing techniques to acquire food.
Survival and extinction
Although the exact cause of Maiasaura’s extinction is unknown, it is thought that the climate of the Late Cretaceous changed rapidly, leading to a decrease in the species’ food source and a decrease in the number of viable habitat available for the dinosaurs. This would have been further compounded by competition from the other species of dinosaurs living during the same time period. Ultimately, it appears that the combination of these factors resulted in their extinction.
Maiasaura’s Legacy
Maiasaura is one of the most well-known dinosaurs of the Late Cretaceous period and has provided scientists with an unprecedented look into the past. Its discovery shed light on the social behaviours, diet, and environment of the period and its fossil record has helped us to better understand the evolution of the dinosaurs. Maiasaura has come to represent a kind of “model organism” for the study of the Late Cretaceous and is a major contribution to our understanding of life in this period.