Paleontologists Discovered Sue the T. Rex 25 Years Ago Today

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Today, Sue the T. Rex fossil, the largest and best preserved T. Rex fossil ever discovered, turns 25—or at the very least, 65,500,025 (but she doesn’t look a day over 60.5 million if you ask me.)

The story is now almost a paleontology legend. On August 12, 1990, while looking for fossils on the Cheyenne Indian Preservation in South Dakota, a flat tire caused a curious Sue Hendrickson (the T. Rex’s namesake) to hunt around previously unsearched cliffs nearby. After discovered fragments of bone, Hendrickson and company soon realized what they’d stumbled upon.

What makes Sue so special is that the fossil is more than 90 percent complete (224 of 321 of known bones), making it the best specimen of a fossilized T. Rex in the world. In fact, it’s so well preserved, that you can even see where muscles and tendons attached on Sue’s skeletal surface, according to Chicago’s Field Museum (where she’s permanently on display). Sue stands at about 40.5 feet in length and its bones weigh near two tons.


Last year, we spoke to Peter Larson, who was the leader of the expedition that eventually unearthed our dear Sue. You can read our entire conversation, which goes into detail about Sue’s discovery, below.

Image by Scott Olson/Getty Images News