User:Sheep81/Sandbox/rex

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[edit] Discoveries

Tyrannosaurus rex discoveries are restricted to North America. The holotype of Tyrannosaurus rex, a partial skull and skeleton originally called AMNH 973, was discovered in the U.S. state of Montana in 1902 and excavated over the next three years. Another specimen (AMNH 5866), found in Wyoming in 1900, was described in the same paper under the name Dynamosaurus imperiosus. At the time of their initial description and naming, these specimens had not been fully prepared and the type specimen of T. rex had not even been fully recovered.^[1] In 1906, after further preparation and examination, Osborn recognized both skeletons as belonging to the same species. Because the name Tyrannosaurus rex had appeared just one page earlier than Dynamosaurus in Osborn's 1905 work, it was considered the older name and has been used since. Had it not been for page order, Dynamosaurus would have become the official name.^[2]

Scale model of the never-completed Tyrannosaurus rex exhibit planned for the American Museum of Natural History by H.F. Osborn.

Both of these specimens, as well as the hindlimbs of a third specimen (AMNH 5881), were collected by Barnum Brown, assistant curator of the American Museum of Natural History and a famous paleontologist in his own right. Brown also discovered the first complete skull of Tyrannosaurus rex, part of another specimen (AMNH 5027) located in Montana in 1907. In total, Brown found five partial Tyrannosaurus skeletons. Osborn planned to mount the similarly-sized AMNH 5027 and AMNH 973 together in dynamic poses as if they were fighting over a carcass.^[3] However, technical difficulties prevented the mount from being executed, and following the 1941 entry of the United States into World War II, the holotype was sold to the Carnegie Museum of Natural History in Pittsburgh for protection against possible bombing raids. The specimen, now dubbed CM 9380, is still mounted in Pittsburgh. After the war, the holotype of Dynamosaurus imperiosus and AMNH 5881 were also sold and now reside in the collections of the Natural History Museum, London (formerly the British Museum of Natural History), where they are known as BMNH R7994 and BMNH R7995, respectively. The American Museum of Natural History features AMNH 5027 in its famed Dinosaur Hall to this day.

Very few other Tyrannosaurus rex skeletons were discovered until the late 1980s. The skull of Nanotyrannus, frequently considered to be a juvenile T. rex, was recovered from Montana in 1942. In 1966, a crew working for the Natural History Museum of Los Angeles County under the direction of Harley Garbani discovered another T. rex (LACM 23844) which included most of the skull of a very large, mature animal. When it was put on display in Los Angeles, LACM 23844 was the largest T. rex skull on exhibit anywhere. Garbani also discovered several other partial skeletons over the next decade (including LACM 23845, holotype of "Albertosaurus" megagracilis), some of which are maintained in the collections of the University of California Museum of Paleontology in Berkeley, California. Other skulls and partial skeletons were discovered in South Dakota and Alberta, Canada in the early 1980s.^[4]

Before 1987, Tyrannosaurus rex was thought to be rare.^[4] However, the last two decades have seen the discovery and description of over a dozen additional specimens. The first, nicknamed "Stan" in honor of its discoverer, amateur paleontologist Stan Sacrison, was found in the Hell Creek Formation near Buffalo, South Dakota, in the spring of 1987. After 30,000 hours of digging and preparation by the Black Hills Institute, beginning in 1992, 65% of a skeleton emerged, including a complete skull. Stan (BHI 3033) is currently on display in the Black Hills Museum of Natural History in Hill City, South Dakota, after an extensive world tour, and replicas sold by the Black Hills Institute are also found in museum exhibit halls around the world. This specimen exhibits many bone pathologies, including broken and healed ribs, a broken and healed neck and a spectacular hole in the back of its head, about the size of a Tyrannosaurus tooth.^[5]

In 1988, local rancher Kathy Wankel discovered another Tyrannosaurus rex in Hell Creek sediments on an island in the Charles M. Russell National Wildlife Refuge of Montana. This specimen was excavated by a team from the Museum of the Rockies led by paleontologist Jack Horner, with assistance from the U.S. Army Corps of Engineers. The specimen, given the number MOR 555 but informally called the "Wankel rex," includes approximately 90% of the skeleton, including the skull, as well as what at the time was the first complete T. rex forelimb. It is now on exhibit at the Museum of the Rockies in Bozeman, Montana.^[4]

Susan Hendrickson of the Black Hills Institute discovered the best-preserved Tyrannosaurus currently known, in the Hell Creek Formation near Faith, South Dakota, on August 12, 1990. This specimen, named "Sue" in honor of its discoverer, soon became embroiled in a legal battle over its ownership. The land on which the fossil was discovered was found to lie within the Cheyenne River Indian Reservation and is occupied by the family of Maurice Williams, a Native American of the Sioux tribe. In 1992, Williams claimed he still owned the fossil, for which the Black Hills Institute had paid him USD 5,000. The local Cheyenne River Sioux Tribe, of which Williams is a member, also claimed ownership. The fossil, as well as many thousands of pages of field notes and business records, were confiscated by the Federal Bureau of Investigation in 1992 and held throughout the ensuing court proceedings. In 1997, the suit was settled in favor of Maurice Williams, due to the fact that his land is technically held in trust for him by the United States government. Therefore, although the Black Hills Institute had paid Williams for the fossil, it was judged that the fossil could be considered "land" which Williams owned but could not legally sell without government permission. The fossil was returned to Williams' ownership and Neal Larson, vice-president of the Black Hills Institute, was sentenced to two years in federal prison for an unrelated customs violation discovered by the FBI while searching through his business records. Williams quickly offered up "Sue" for auction by Sotheby's in New York, where it was sold to the Field Museum of Natural History in Chicago for USD 8.4 million — the highest price ever paid for a fossil. Preparation of "Sue" (FMNH PR2081) was completed at the Field Museum and her skeleton was placed on exhibit on May 17, 2000.^[6][7] Over 90% of the skeleton was recovered, allowing the first complete description of a Tyrannosaurus rex skeleton.^[8]

Following the sale of "Sue," another Tyrannosaurus rex skeleton, dubbed "Z-rex", was put up for auction on eBay in 2000 with an asking price of over USD 8 million. It failed to sell online but was purchased for an undisclosed price in 2001 by British millionaire Graham Ferguson Lacey, who renamed the skeleton "Samson" after the Biblical figure of the same name. This specimen, discovered on private land in South Dakota in 1992, includes a complete and undistorted skull, which was prepared by the Carnegie Museum in Pittsburgh starting in May 2004.^[9] After preparation was complete in March 2006, the specimen was returned to its owner, who plans to put it on an educational tour.^[10]

Jane

Scottie

B. rex and other MOR rexes (including soft tissue)

MOR 008

Tinker