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MAIASAURA DINOSAUR a Member of the Hadrosauridae Family, the Maiasaura Peeblesorum Is a Classic North American Herbivorous Dinosaur with a “Duck-Billed” Head

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MAIASAURA DINOSAUR a Member of the Hadrosauridae Family, the Maiasaura Peeblesorum Is a Classic North American Herbivorous Dinosaur with a “Duck-Billed” Head MAIASAURA DINOSAUR A member of the Hadrosauridae family, the Maiasaura peeblesorum is a classic North American herbivorous dinosaur with a “duck-billed” head. Maiasaura is Greek for “good mother lizard” because evidence shows that they nurtured and raised their young for a significantly longer period of time than other dinosaurs. A large nesting site discovered in Montana has also made the Maiasaura popular amongst paleontologists. COMPLETE MOUNTED “DUCK-BILLED” DINOSAUR Maiasaura peeblesorum Late Cretaceous Two Medicine Formation, Northern Montana The present specimen being offered is an exquisitely mounted sub-adult Maiasaura peeblesorum measuring over 17 feet (5 meters) in length. It is one of the most complete mounted specimens of this species known and it possesses a particularly well preserved skull. An important feature of the discovery is the fact that this specimen was found with incredible natural articulation of the hind legs and tail. As it is still a sub-adult, the not yet fused astragalus and calcaneum displays amazing articulation with the tibia, fibula on both hind legs. The tail section features 36 well-preserved caudal vertebrae and was also found together in articulation. Though a composite, the skeleton consists of approximately 80% original bones which were professionally assembled to be scientifically accurate. Discovered in a large bone bed from the Two Medicine Formation of Northern Montana in 1992, it wasn’t until 15 years later that this impressive dinosaur was mounted using the most modern techniques available. By using a bracket-mount system, no bones have been drilled or compromised in any way during the mounting procedure. Every bone is removable from the supporting armature for scientific study. An innovative “gravity mount” system is used on the feet; individual toe bones fit into individual slots and gravity holds them in place. These bones can be removed very easily without disrupting the rest of the mount. The skull possesses a unique mounting system that allows it to move side-to-side, approximately up to 30°; also, the mandibles can be positioned with the mouth opened or closed. Maiasaura Maiasaura was a large, herbivorous, duck-billed dinosaur that lived during the late Cretaceous period. Adult maiasaurs grew upwards of 30 feet (9 meters) in length, stood 9 feet (2.7 meters) tall and weighed 3 to 4 tons. Possessing front legs that were much shorter than their rear legs; maiasaurs utilized both bipedal and quadripedal motion and were relatively fast dinosaurs; having to move quickly to evade predators such as the Albertosaurus and Troodon. There is evidence that maiasaurs travelled in large herds across late Cretaceous North America; some possibly ten-thousand strong. With so many mouths to feed, these herds needed to travel seasonally in search of food, returning annually to breed at their original nesting sites. Maiasaur nests usually contained more than 20 eggs, each of which were as big as those of the modern ostrich. Rather than sitting on the eggs, the parents placed vegetation in the nest to rot in order to generate heat for incubation. Maiasaura was named the “good mother lizard” because fossil evidence suggests Maiasaur mothers nurtured their hatchlings until they doubled in size — longer than many other dinosaurs stayed with their young. Infant maiasaurs did not have legs capable of walking, yet fossil evidence shows partially worn teeth, therefore the parents had to provide for their young. The largest nesting site in the Western Hemisphere is Egg Mountain in Montana; discovered in 1977, this site had over 200 individual Maiasaura fossils and countless nests. The discovery of a nest with remains of trampled eggshells and babies too large to be hatchlings led to the name Maiasaura being chosen by paleontologist Jack Horner and Robert Makela in 1979. This still stands as the only female name given to a dinosaur. Montana designated the duck-bill dinosaur, Maiasaura peeblesorum, as the official state fossil in 1985. The Two Medicine Formation The Two Medicine Formation, where the present specimen was discovered, is one of the most paleontologically significant rock layers in the world. From its sediments the first dinosaur eggs in North America were discovered, along with the first nest of infant dinosaurs in the world. The formation was deposited 83.5 to 70.5 million years ago during the Late Cretaceous period. It is prevalent in Montana east of the Rocky Mountains and is mostly exposed as outcrops and badlands in the grassy plains. Many species of hadrosaurs, ankylosaurs, ceratopsians, avians, deinonychosaurs, oviraptorosaurs, ornithopods and tyrannosaurids have been found within the deposits of this formation and it is one of the most important dinosaur-bearing formations in the world. “Cory” This specimen is nicknamed “Cory”; the preparators of this specimen use a tropical storm naming system for their dinosaurs; going through the alphabet, female names first (Alice, Betty, Candace... to Zelda) and then progressing to male names. “Cory” is the 29th dinosaur that this team has found and is the name of the team’s production manager. NATURAL HISTORY For more information, contact: David Herskowitz Peter Wiggins Director of Natural History Assistant Director of Natural History [email protected] [email protected] 214-409-1610 214-409-1639 800-872-6467 ext. 1610 800-872-6467 ext. 1639 TRICERATOPS DINOSAUR Natural HistorY AUCTION Free catalog and The Collector’s Handbook ($65 Value) for new clients. Please submit auction invoices of $1000+ in this category, from any source. Include your contact information and mail to Heritage, fax 214-409-1425, email [email protected], or call 866-835-3243. For more details, go to HA.com/FCO. Annual Sales Exceed $600 Million | 500,000+ Online Bidder-Members 3500 Maple Avenue | Dallas, Texas 75219 | 800-872-6467 | HA.com DALLAS | NEW YORK | BEVERLY HILLS | PARIS | GENEVA 20633 12-21-10.
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