A Boy (Girl?) Named Sue
August 12, 1990: Skeleton of Tyrannosaurus Rex Discovered
On this day in 1990, fossil hunter Susan Hendrickson discovers three huge bones jutting out of a cliff near Faith, South Dakota. They turn out to be part of the largest-ever Tyrannosaurus rex skeleton ever discovered, a 65 million-year-old specimen dubbed Sue, after its discoverer.
Amazingly, Sue’s skeleton was over 90 percent complete, and the bones were extremely well-preserved. Hendrickson’s employer, the Black Hills Institute of Geological Research, paid $5,000 to the land owner, Maurice Williams, for the right to excavate the dinosaur skeleton, which was cleaned and transported to the company headquarters in Hill City.
In 1992, a long legal battle began over Sue. The U.S. Attorney’s Office claimed Sue’s bones had been seized from federal land and were therefore government property. It was eventually found that Williams, a part-Native American and member of the Cheyenne River Sioux tribe, had traded his land to the tribe two decades earlier to avoid paying property taxes, and thus his sale of excavation rights to Black Hills had been invalid.
In October 1997, Chicago’s Field Museum purchased Sue at public auction at Sotheby’s in New York City for $8.36 million, financed in part by the McDonald’s and Disney corporations.
Sue’s skeleton went on display at the Field Museum in May 2000. The tremendous T.rex skeleton–13 feet high at the hips and 42 feet long from head to toe–is displayed in one of the museum’s main halls. Another exhibit gives viewers a close-up view of Sue’s five foot-long, 2,000-pound skull with its 58 teeth, some as long as a human forearm.
Sue’s extraordinarily well-preserved bones have allowed scientists to determine many things about the life of T.rex. They have determined that the carnivorous dinosaur had an incredible sense of smell, as the olfactory bulbs were each bigger than the cerebrum, the thinking part of the brain. In addition, Sue was the first T.rex skeleton to be discovered with a wishbone, a crucial discovery that provided support for scientists’ theory that birds are a type of living dinosaur. One thing that remains unknown is Sue’s actual gender; to determine this, scientists would have to compare many more T.rex skeletons than the 22 that have been found so far.
Close examination of the bones revealed that Sue was 28 years old when she died, making her the oldest T. rex known. During her life this carnivore received several injuries and suffered from numerous pathologies. An injury to the right shoulder region of Sue resulted in a damaged shoulder blade, a torn tendon in the right arm, and three broken ribs. This damage subsequently healed (though one rib healed into two separate pieces), indicating Sue survived the incident. The left fibula is twice the diameter of the right one, likely a result of infection.
Some of the tail vertebrae are fused in a pattern typical of arthritis due to injury. The animal is also believed to have suffered from gout. In addition, there is extra bone in some of the tail vertebrae likely caused by the stresses brought on by Sue’s great size. Sue’s tendon avulsion was likely caused by contact with struggling prey. Sue did not die as a result of any of these injuries; her cause of death is not known.