A very important work component for the Dinosaur Institute staff is to expand the fossil collections of Mesozoic vertebrates. In order to achieve this, our staff undertake annual research expeditions to the dinosaur-rich badlands of the American West, as well as expeditions to remote parts of South America and Asia. These important and exciting expeditions are detailed below.
Fieldwork in the United States has focused on federal lands (Bureau of Land Management) of eastern Wyoming (Niobrara County) and Montana (Carter County), at various Late Cretaceous localities of the Lance and Hell Creek formations, respectively. These deposits are important because they document the end of the era in which large dinosaurs dominated all land ecosystems. A series of expeditions have resulted in significant new collections of large dinosaurs (Triceratops, Tyrannosaurus, Edmontonia, Thescelosaurus, Ornithomimus, and others), as well as a diversity of crocodiles, turtles, birds, and mammals that lived alongside these dinosaurs.
More recent fieldwork has explored the Late Jurassic Morrison Formation and the Early Cretaceous Cedar Mountain Formation of southeastern Utah (San Juan County). New finds include a diversity of sauropod fossils and an array of dinosaur tracks. The Late Jurassic is an important time period as it documents some of the earliest known birds and plays an important role in biogeographic studies.
Other recent fieldwork has taken the Dinosaur Institute team to Petrified Forest National Park in Arizona as well as to the Mojave Dessert in Eastern California.
A highlight of these expeditions was the collection of the Tyrannosaurus rex known as "Thomas," which with more than two-thirds of its skeleton preserved (skull, much of its vertebral column, ribs and shoulder girdles, pelvis and both hind limbs) ranks among the best specimens of this species. These expeditions have also offered training to volunteers of the Dinosaur Institute and a host of students from many different American and foreign universities (including the University of Southern California, South Dakota School of Mines, Montana State University, University College Dublin, Universidad Nacional de San Luis, and others). Dinosaur Institute donors Andrew Getty, Tom Thornbury, and Janice Jay-Holland were instrumental in making these expeditions possible.
These expeditions have explored a number of Cretaceous localities distributed in Kazakhstan, China, and Mongolia with the intent of better understanding the diversity of dinosaurs and other vertebrates that lived across what is now central Asia. We chose less extensively surveyed localities than those in southern Mongolia (Gobi Desert) or northeastern China (Liaoning Province). Work in Kazakhstan – in collaboration with University College Dublin (Ireland) and the Almaty's Zoological Institute (Kazakhstan) – has focused on the western portion of the country, east of the Aral Sea and near the middle portion of the Syr Darya River. Late Cretaceous fossils recovered from the locality of Shak-Shak and adjacent outcrops documented a diversity of dinosaurs, even if these are largely represented by teeth and other isolated elements.
Our fieldwork in China – in collaboration with the Geological Museum of China (Beijing) – centered on the western margin of the Junggar Basin of the Xinjiang Uighur Autonomous Region, in northwestern China. Early Cretaceous outcrops around the village of Urho, north of Kalamay, produced a large number of specimens of the sharp-snouted pterosaur Dsungaripterus, well-preserved material of the primitive crocodile Edentosuchus (a tiny crocodilian with multicuspidal teeth), and a number of dinosaur specimens including Psittacosaurus, an unnamed primitive ornithopod, and stegosaurs. Fieldwork in Mongolia – in collaboration with the Natural History Museum of Ulaan Bataar – focused on the western portion of the country, particularly at the Early Cretaceous pterosaur locality of Tatal, north of Hovd. The National Geographic Society and the American Association of Museums made these expeditions possible.
Our South American expeditions – in collaboration with the Carmen Funes Museum (Plaza Huincul, Argentina) – have largely focused on the extraordinary sauropod nesting site of Auca Mahuevo and a series of adjacent localities (northeastern Neuquén Province, Patagonia, Argentina). Thousands of eggs have been identified, mapped, and collected from these Late Cretaceous localities. Many eggs contain the remains of bones and skin of embryos, which have allowed identification of them as those of titanosaur sauropods. A number of specific studies about the anatomy and development of the embryos, the characteristics of the eggs and nests, and a diversity of inferences about the reproductive behavior of sauropods have resulted from the fossils collected during these expeditions.
Other expeditions to Patagonia have surveyed the Late Cretaceous exposures of the Sierra del Portezuelo, west of Plaza Huincul (Neuquén Province), where a diversity of theropod, ornithopod, and titanosaur sauropod remains have been collected. The Auca Mahuevo expeditions have provided training to a large number of students, both from Argentina and elsewhere, and have been instrumental in the creation of many educational programs including the Tiniest Giants exhibition. These expeditions were made possible by grants and support from a variety of sources including the National Geographic Society, the Infoquest Foundation, and the Fundación Antorchas.