By: Jeremy Sun
On July 31, 2022, Jessin Fisher (10), his brother Liam (7), and their cousin Kaiden Madsen (9) embarked on a fossil-hunting expedition in the Hell Creek Formation of the North Dakota Badlands. Known for its abundance of dinosaur bones, the trio was eager to uncover some treasures of their own. In the end, they stumbled upon one of the few juvenile T. rex skeletons ever discovered!
Before coming upon these fossils, Liam and his father, Sam Fisher, noticed a long, gray-white bone protruding from the ground. Liam’s father called for Jessin and Kaiden to come. Liam’s father asked what was poking out of the ground and Jessin said, “That’s a dinosaur.”
Sam sent a photo of the fossil to Dr. Tyler Lyson, a paleontologist at the Denver Museum of Nature & Science, who validated Jessin’s theory. In 2023, after obtaining the necessary permits, Dr. Lyson formed an excavation team that included the three boys.
Initially, he believed the bone was from a duckbill dinosaur, a more frequently found species. However, shortly after arriving at the site, Dr. Lyson and Jessin discovered what appeared to be a T. rex tooth. Further excavation revealed three additional teeth attached to a jaw!
According to the DOGOnews article “Three Young Explorers Discover A Rare, Teenage T. Rex” by Alvaro Aragon, Dr. Lyson told the Associated Press, “Instead of finding cervical vertebrae, we found the lower jaw with several teeth sticking out of it. And it doesn’t get any more diagnostic than that, seeing these giant tyrannosaurus teeth staring back at you.”
The team found the dinosaur bones encased in a massive sandstone block weighing 6,000 pounds and measuring eight feet across. Extracting them took 11 days. Although the skeleton was incomplete, it was well-preserved and included parts such as the lower leg, hips, pelvis, tail vertebrae, and most of the skull.
The researchers’ estimation suggests the T. rex measured about 25 feet in length and stood around 10 feet tall. It weighed an estimated 3,500 pounds, approximately two-thirds the size of a fully-grown adult. They hypothesize the dinosaur was between 13 and 15 years old when it perished some 67 million years ago.
This T. rex fossil find was huge. “Juvenile [T.] rex specimens are extremely rare,” Dr. Lyson said. “This find is significant to researchers because the ‘Teen Rex’ specimen may help answer questions about how the king of dinosaurs grew up.”
Liam, Jessin, and Kaiden lovingly named the young dinosaur “The Brothers.” It made its debut at the Denver museum on June 21, 2024. The exhibit, titled “Exploring Teen Rex,” features a documentary that recounts the boys’ extraordinary journey of discovery.