A SPECTACULAR COMPLETE HADROSAURID SKELETON
Maiasaura peeblesorum
Cretaceous, Campanian stage
Two Medicine Formation, Montana
This spectacular skeleton represents one of the most complete specimens of the species Maiasaura peeblesorum ever to be offered to the public. The Maiasaur was one of the numerous "duck-billed" dinosaurs that roamed the plains of Asia, Europe and North America in massive herds during the Upper Cretaceous period 99-65 million years ago. The duck-billed dinosaurs were from the herbivorous Hadrosaurid family, so-named for the shape of their flattened, duck-like "beaks", ideal for stripping the prehistoric foliage of leaves and twigs; their strong forearms, meanwhile, could be used equally well for pulling down branches to within reach, or for walking or running on all fours from the fearsome predators that shared their habitat (most notably the T-Rex).

The Hadrosaurids were a huge herbivorous dinosaur lineage that included such famous animals as the "dinosaur mummy" Leonardo and Hadrosaurus foulkii, which in 1858 became the very first dinosaur ever found in the United States, and was later designated as the State Fossil of New Jersey. Like all hadrosaurs, Maiasaura was herbivorous and possessed a huge battery of chisel-like teeth designed specifically to grind plants to a digestible pulp. It shared its world with a wide variety of other dinosaurs such as the pachycephalosaur Prenocephale; several velociraptor-like troodontids; Gallimimus, the ostrich-mimic depicted in Jurassic Park; and the giant tyrannosaurid carnivore Tarbosaurus. The Maiasaur was first discovered and classified in the 1970s; in 1977 Marion Brandvold and her son David Trexler uncovered an enormous bone-bed/nesting ground in what is now known as Egg Mountain in south-western Montana, and Laurie Trexler discovered the species holotype; it was named by Robert Makela and Jack R. Horner (paleontological consultant for Jurassic Park) in 1979.

The genus name Maiasaura means "good mother lizard" and is the only female name given to a dinosaur; the first remains discovered were with nests of eggs and hatchlings, indicating that unlike modern reptiles and most other dinosaurs it raised its offspring rather than abandoning them to their fate. Nest specimens uncovered reveal that the eggs were first incubated packed in rotting vegetation rather than by the mother sitting over them; when the hatchlings were born, however, their legs were too weak to carry them from the nest, and the presence of worn teeth amongst the still nest-bound young indicates that the parent(s) would bring food directly to the nest for the first period of the young dinosaurs' life, possibly for as long as one year. Such nests usually contained up to 25 grapefruit-sized eggs, and were typically laid in groups; the Egg Mountain discovery comprised 40 nests arranged over a 2.5 acre area in a part of Montana that was a Maiasaur Island in the Late Cretaceous Interior Seaway.

The present example is a sub-adult, named "Cory", and cuts a strikingly impressive figure, at over 15 feet long and with a superb woody patina to the bones. It bears the flattened beak distinctive of the family, and a particularly good skull overall; in total over 80% of the bone is original throughout the skeleton. Mounted on a wheeled metal base in a highly life-like pose, not only is this a rare and unusually complete specimen but it has been prepared to the highest of standards; the armature is outstanding, almost invisible, yet the bones are exclusively gravity-mounted with no holes or attachments created for display purposes, and the hind limbs even retain their natural articulation. In addition, the skull has been mounted in such a way that not only can it be moved from side to side through 30° but the jaws open and close as well. A world-class specimen in every way.