No dinosaur in the world compares to SUE – the largest, most complete, and best preserved Tyrannosaurus rex ever found. Since her unveiling at The Field Museum in 2000, millions of visitors each year have marveled at Chicago’s prehistoric giant. In addition, people all over the globe – from Alaska to Dubai – have seen the special traveling exhibition, A T. rex Named SUE, which features a full-size cast model of the dinosaur and many hands-on activities.
SUE’s sex is unknown (she’s named after Sue Hendrickson, the fossil hunter who discovered her in South Dakota in 1990). But there’s much we do know: Over 90 percent of her bones were found – it’s very unusual for a fossil to be so complete. This proves that after she died (probably by a riverbank), she was quickly covered in mud before scavengers could reach her or weather could erode her. SUE’s skeleton reveals important information about her life. Her massive frame supported a body that weighed nearly seven tons. Wounds on her bones that were first thought to be bite marks and battle scars were later discovered to be lesions probably caused by infections. By counting the rings in SUE’s bones – much like counting rings in tree stumps – scientists discovered that she grew rapidly during adolescence and was 28 years old when she died – the upper range of T. rex life expectancy.
Researchers performed a CAT scan on SUE’s skull and discovered that T. rex sense of smell was especially keen. Although her brain was just large enough to hold a quart of liquid, the two olfactory lobes in her skull (used to detect and interpret smell) were about the size of grapefruits! That sense of smell was essential for finding food, and sharp, serrated teeth – some measuring one foot in length – were the steak knives she used for slicing through meat. But we don’t know for sure if T. rex was a hunter or a scavenger, or both.
The Field Museum acquired SUE at an auction in New York for a record total price of $8.36 million (that’s still the largest amount ever paid for a fossil.) The fossils arrived still encased in rock, or what scientists call matrix. To release and restore them, the Museum built the glass-enclosed, state-of-the-art McDonald’s Fossil Preparation Laboratory. There, paleontologists painstakingly cleaned each fossil with tools not unlike those used by dentists to clean teeth. Twenty-five thousand hours* were spent on this delicate process – 3,500 hours on the skull alone (*that equates to one person working 15 years full-time!) Scientists removed almost three tons of rock and debris for more than two years to get SUE ready for display! Since then, scientists continue to clean and prepare other fossils in the laboratory, and Museum visitors enjoy watching them work.
Today, SUE stands in the Museum’s Stanley Field Hall. All the bones on display are her actual bones except for her enormous skull, which is a cast. SUE’s real skull weighs over 600 pounds and is too heavy for the structure that supports the rest of the skeleton. The real skull can be seen on the upper level mezzanine along with an exhibition describing how SUE was discovered, and preserved. In addition visitors can learn more about T. rex in general and see just how much SUE has helped scientists understand these fearsome creatures.
For more information about The Field Museum and SUE, visit fieldmuseum.org
SUE at The Field Museum is made possible by McDonald’s Corporation. A major sponsor of SUE is Walt Disney World Resort. Additional support has been provided by the Illinois Department of Natural Resources/Illinois State Museum. The Elizabeth Morse Charitable Trust is the generous sponsor of this exhibition.