Sue was a big dinosaur. 

Sue was a huge dinosaur. 


Sue is one of the best T. rex fossils ever found. 

Long ago, water and mud covered the dinosaur. This helped keep the bones safe from other animals. The rushing water mixed the bones together. 
Sue lived with many health problems. She had a bone infection called osteomyelitis. This is a sickness in the bone. She also had arthritis. This is a condition that makes joints stiff. Now, Sue lives at the Field Museum in Chicago.
Sue is one of the most famous dinosaurs in the world. 

Finding Sue was a bit of a surprise. 
There was a long fight over who owned the bones.
Preparing the bones was a very careful job. 
Sue tells us a lot about how dinosaurs lived.
Sue, officially designated FMNH PR 2081, is a legendary Tyrannosaurus rex fossil. 
The discovery of Sue happened by chance in August 1990. A team from the Black Hills Institute was searching for fossils near Faith, South Dakota. 
Preservation of the skeleton was driven by specific environmental events. Scientists believe Sue was covered by water and mud shortly after her death. This rapid burial protected the bones from being carried away by other animals. However, the rushing water also mixed the skeleton together. When the team found her, the hip bones were positioned above the skull. The leg bones were also intertwined with the ribs. This specimen is 73 percent complete when counting individual elements. Of the 360 known T. rex bones, approximately 250 were recovered from this site.
Following the discovery, a complex legal dispute arose regarding ownership. Maurice Williams, a member of the Sioux tribe, owned the land where the fossil was found. The Black Hills Institute had paid Williams for the right to excavate the remains. Williams later argued that he only allowed the removal for cleaning, not for a sale. The property was held in trust by the United States Department of the Interior. In 1992, the FBI and the South Dakota National Guard seized the fossil. After lengthy legal battles, the court decreed that Williams retained ownership. 
In October 1997, Sue was sold at a high-stakes auction. The Field Museum in Chicago wanted to ensure the fossil stayed in a public museum. To afford the purchase, they gathered support from many sources. These included the California State University system, Walt Disney Parks and Resorts, and McDonald's. The Field Museum won the auction with a bid of $8.3 million. This was the highest price ever paid for a fossil at that time. Since then, other fossils like Stan and Apex have sold for more. 
Preparing the fossil for display required extreme precision and technology. Preparators had to remove the rock, known as the matrix, from the bones. They worked in specialized labs, including one at Disney's Animal Kingdom. Because some bones were missing, scientists created purple plastic models to complete the skeleton.
Sue's bones offer a detailed medical history of her life. She was likely 33 years old at the time of death. This makes her the oldest known T. rex specimen currently published. She survived several injuries, including three broken ribs and a torn tendon in her right arm. However, she also suffered from various illnesses. She had an infection called osteomyelitis, which affected her left fibula.
In terms of scale, Sue was a truly massive animal. She is approximately 12 meters long along her centra. Her weight is estimated through various studies. Some estimates place her at 7,377 kg, while others suggest a range between 5,531 kg and 9,224 kg. Her skull alone weighs 272 kilograms. She possesses the longest known belly rib among theropods. She also has the longest known pubis measured among Cretaceous theropods.
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